)]}'
{
  "log": [
    {
      "commit": "79da0644a8e0838522828f106e4049639eea6baf",
      "tree": "4dbb8e1a3a4be78a79f14e8ebac5d6fe817a2fb4",
      "parents": [
        "9f3a6284880ceea452903e2043c88d7226736318"
      ],
      "author": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Feb 23 08:40:43 2010 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Feb 23 08:40:43 2010 +0100"
      },
      "message": "Revert \"block: improve queue_should_plug() by looking at IO depths\"\n\nThis reverts commit fb1e75389bd06fd5987e9cda1b4e0305c782f854.\n\n\"Benjamin S.\" \u003csbenni@gmx.de\u003e reports that the patch in question\ncauses a big drop in sequential throughput for him, dropping from\n200MB/sec down to only 70MB/sec.\n\nNeeds to be investigated more fully, for now lets just revert the\noffending commit.\n\nConflicts:\n\n\tinclude/linux/blkdev.h\n\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "ae54abed636d18f7939c965f21ad126001dbe34c",
      "tree": "6eecccf1cb910073273699d58e620b99bf32d1a6",
      "parents": [
        "fc76be434d90bcd57a0ea6b93a2e66a3fec4b664"
      ],
      "author": {
        "name": "Shaohua Li",
        "email": "shaohua.li@intel.com",
        "time": "Fri Feb 05 13:11:45 2010 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Fri Feb 05 13:11:45 2010 +0100"
      },
      "message": "cfq-iosched: split seeky coop queues after one slice\n\nCurrently we split seeky coop queues after 1s, which is too big. Below patch\nmarks seeky coop queue split_coop flag after one slice. After that, if new\nrequests come in, the queues will be splitted. Patch is suggested by Corrado.\n\nSigned-off-by: Shaohua Li \u003cshaohua.li@intel.com\u003e\nReviewed-by: Corrado Zoccolo \u003cczoccolo@gmail.com\u003e\nAcked-by: Jeff Moyer \u003cjmoyer@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "1efe8fe1c2240acc476bed77740883df63373862",
      "tree": "9aab2376b46432d721cdb7cf6f3be992a8951c0c",
      "parents": [
        "bcf4dd43424cdfd8195f3955300a579fe58e9911"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Tue Feb 02 20:45:46 2010 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Feb 02 20:46:10 2010 +0100"
      },
      "message": "cfq-iosched: Do not idle on async queues\n\nFew weeks back, Shaohua Li had posted similar patch. I am reposting it\nwith more test results.\n\nThis patch does two things.\n\n- Do not idle on async queues.\n\n- It also changes the write queue depth CFQ drives (cfq_may_dispatch()).\n  Currently, we seem to driving queue depth of 1 always for WRITES. This is\n  true even if there is only one write queue in the system and all the logic\n  of infinite queue depth in case of single busy queue as well as slowly\n  increasing queue depth based on last delayed sync request does not seem to\n  be kicking in at all.\n\nThis patch will allow deeper WRITE queue depths (subjected to the other\nWRITE queue depth contstraints like cfq_quantum and last delayed sync\nrequest).\n\nShaohua Li had reported getting more out of his SSD. For me, I have got\none Lun exported from an HP EVA and when pure buffered writes are on, I\ncan get more out of the system. Following are test results of pure\nbuffered writes (with end_fsync\u003d1) with vanilla and patched kernel. These\nresults are average of 3 sets of run with increasing number of threads.\n\nAVERAGE[bufwfs][vanilla]\n-------\njob       Set NR  ReadBW(KB/s)   MaxClat(us)    WriteBW(KB/s)  MaxClat(us)\n---       --- --  ------------   -----------    -------------  -----------\nbufwfs    3   1   0              0              95349          474141\nbufwfs    3   2   0              0              100282         806926\nbufwfs    3   4   0              0              109989         2.7301e+06\nbufwfs    3   8   0              0              116642         3762231\nbufwfs    3   16  0              0              118230         6902970\n\nAVERAGE[bufwfs] [patched kernel]\n-------\nbufwfs    3   1   0              0              270722         404352\nbufwfs    3   2   0              0              206770         1.06552e+06\nbufwfs    3   4   0              0              195277         1.62283e+06\nbufwfs    3   8   0              0              260960         2.62979e+06\nbufwfs    3   16  0              0              299260         1.70731e+06\n\nI also ran buffered writes along with some sequential reads and some\nbuffered reads going on in the system on a SATA disk because the potential\nrisk could be that we should not be driving queue depth higher in presence\nof sync IO going to keep the max clat low.\n\nWith some random and sequential reads going on in the system on one SATA\ndisk I did not see any significant increase in max clat. So it looks like\nother WRITE queue depth control logic is doing its job. Here are the\nresults.\n\nAVERAGE[brr, bsr, bufw together] [vanilla]\n-------\njob       Set NR  ReadBW(KB/s)   MaxClat(us)    WriteBW(KB/s)  MaxClat(us)\n---       --- --  ------------   -----------    -------------  -----------\nbrr       3   1   850            546345         0              0\nbsr       3   1   14650          729543         0              0\nbufw      3   1   0              0              23908          8274517\n\nbrr       3   2   981.333        579395         0              0\nbsr       3   2   14149.7        1175689        0              0\nbufw      3   2   0              0              21921          1.28108e+07\n\nbrr       3   4   898.333        1.75527e+06    0              0\nbsr       3   4   12230.7        1.40072e+06    0              0\nbufw      3   4   0              0              19722.3        2.4901e+07\n\nbrr       3   8   900            3160594        0              0\nbsr       3   8   9282.33        1.91314e+06    0              0\nbufw      3   8   0              0              18789.3        23890622\n\nAVERAGE[brr, bsr, bufw mixed] [patched kernel]\n-------\njob       Set NR  ReadBW(KB/s)   MaxClat(us)    WriteBW(KB/s)  MaxClat(us)\n---       --- --  ------------   -----------    -------------  -----------\nbrr       3   1   837            417973         0              0\nbsr       3   1   14357.7        591275         0              0\nbufw      3   1   0              0              24869.7        8910662\n\nbrr       3   2   1038.33        543434         0              0\nbsr       3   2   13351.3        1205858        0              0\nbufw      3   2   0              0              18626.3        13280370\n\nbrr       3   4   913            1.86861e+06    0              0\nbsr       3   4   12652.3        1430974        0              0\nbufw      3   4   0              0              15343.3        2.81305e+07\n\nbrr       3   8   890            2.92695e+06    0              0\nbsr       3   8   9635.33        1.90244e+06    0              0\nbufw      3   8   0              0              17200.3        24424392\n\nSo looks like it might make sense to include this patch.\n\nThanks\nVivek\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "bcf4dd43424cdfd8195f3955300a579fe58e9911",
      "tree": "ad4f94fdb111dc624b58a6caa9ce45da64c910ee",
      "parents": [
        "9e9432c267e4047db98b9d4fba95099c6effcef9"
      ],
      "author": {
        "name": "Gui Jianfeng",
        "email": "guijianfeng@cn.fujitsu.com",
        "time": "Mon Feb 01 09:58:54 2010 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Mon Feb 01 09:58:54 2010 +0100"
      },
      "message": "blk-cgroup: Fix potential deadlock in blk-cgroup\n\nI triggered a lockdep warning as following.\n\n\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\n[ INFO: possible circular locking dependency detected ]\n2.6.33-rc2 #1\n-------------------------------------------------------\ntest_io_control/7357 is trying to acquire lock:\n (blkio_list_lock){+.+...}, at: [\u003cc053a990\u003e] blkiocg_weight_write+0x82/0x9e\n\nbut task is already holding lock:\n (\u0026(\u0026blkcg-\u003elock)-\u003erlock){......}, at: [\u003cc053a949\u003e] blkiocg_weight_write+0x3b/0x9e\n\nwhich lock already depends on the new lock.\n\nthe existing dependency chain (in reverse order) is:\n\n-\u003e #2 (\u0026(\u0026blkcg-\u003elock)-\u003erlock){......}:\n       [\u003cc04583b7\u003e] validate_chain+0x8bc/0xb9c\n       [\u003cc0458dba\u003e] __lock_acquire+0x723/0x789\n       [\u003cc0458eb0\u003e] lock_acquire+0x90/0xa7\n       [\u003cc0692b0a\u003e] _raw_spin_lock_irqsave+0x27/0x5a\n       [\u003cc053a4e1\u003e] blkiocg_add_blkio_group+0x1a/0x6d\n       [\u003cc053cac7\u003e] cfq_get_queue+0x225/0x3de\n       [\u003cc053eec2\u003e] cfq_set_request+0x217/0x42d\n       [\u003cc052c8a6\u003e] elv_set_request+0x17/0x26\n       [\u003cc0532a0f\u003e] get_request+0x203/0x2c5\n       [\u003cc0532ae9\u003e] get_request_wait+0x18/0x10e\n       [\u003cc0533470\u003e] __make_request+0x2ba/0x375\n       [\u003cc0531985\u003e] generic_make_request+0x28d/0x30f\n       [\u003cc0532da7\u003e] submit_bio+0x8a/0x8f\n       [\u003cc04d827a\u003e] submit_bh+0xf0/0x10f\n       [\u003cc04d91d2\u003e] ll_rw_block+0xc0/0xf9\n       [\u003cf86e9705\u003e] ext3_find_entry+0x319/0x544 [ext3]\n       [\u003cf86eae58\u003e] ext3_lookup+0x2c/0xb9 [ext3]\n       [\u003cc04c3e1b\u003e] do_lookup+0xd3/0x172\n       [\u003cc04c56c8\u003e] link_path_walk+0x5fb/0x95c\n       [\u003cc04c5a65\u003e] path_walk+0x3c/0x81\n       [\u003cc04c5b63\u003e] do_path_lookup+0x21/0x8a\n       [\u003cc04c66cc\u003e] do_filp_open+0xf0/0x978\n       [\u003cc04c0c7e\u003e] open_exec+0x1b/0xb7\n       [\u003cc04c1436\u003e] do_execve+0xbb/0x266\n       [\u003cc04081a9\u003e] sys_execve+0x24/0x4a\n       [\u003cc04028a2\u003e] ptregs_execve+0x12/0x18\n\n-\u003e #1 (\u0026(\u0026q-\u003e__queue_lock)-\u003erlock){..-.-.}:\n       [\u003cc04583b7\u003e] validate_chain+0x8bc/0xb9c\n       [\u003cc0458dba\u003e] __lock_acquire+0x723/0x789\n       [\u003cc0458eb0\u003e] lock_acquire+0x90/0xa7\n       [\u003cc0692b0a\u003e] _raw_spin_lock_irqsave+0x27/0x5a\n       [\u003cc053dd2a\u003e] cfq_unlink_blkio_group+0x17/0x41\n       [\u003cc053a6eb\u003e] blkiocg_destroy+0x72/0xc7\n       [\u003cc0467df0\u003e] cgroup_diput+0x4a/0xb2\n       [\u003cc04ca473\u003e] dentry_iput+0x93/0xb7\n       [\u003cc04ca4b3\u003e] d_kill+0x1c/0x36\n       [\u003cc04cb5c5\u003e] dput+0xf5/0xfe\n       [\u003cc04c6084\u003e] do_rmdir+0x95/0xbe\n       [\u003cc04c60ec\u003e] sys_rmdir+0x10/0x12\n       [\u003cc04027cc\u003e] sysenter_do_call+0x12/0x32\n\n-\u003e #0 (blkio_list_lock){+.+...}:\n       [\u003cc0458117\u003e] validate_chain+0x61c/0xb9c\n       [\u003cc0458dba\u003e] __lock_acquire+0x723/0x789\n       [\u003cc0458eb0\u003e] lock_acquire+0x90/0xa7\n       [\u003cc06929fd\u003e] _raw_spin_lock+0x1e/0x4e\n       [\u003cc053a990\u003e] blkiocg_weight_write+0x82/0x9e\n       [\u003cc0467f1e\u003e] cgroup_file_write+0xc6/0x1c0\n       [\u003cc04bd2f3\u003e] vfs_write+0x8c/0x116\n       [\u003cc04bd7c6\u003e] sys_write+0x3b/0x60\n       [\u003cc04027cc\u003e] sysenter_do_call+0x12/0x32\n\nother info that might help us debug this:\n\n1 lock held by test_io_control/7357:\n #0:  (\u0026(\u0026blkcg-\u003elock)-\u003erlock){......}, at: [\u003cc053a949\u003e] blkiocg_weight_write+0x3b/0x9e\nstack backtrace:\nPid: 7357, comm: test_io_control Not tainted 2.6.33-rc2 #1\nCall Trace:\n [\u003cc045754f\u003e] print_circular_bug+0x91/0x9d\n [\u003cc0458117\u003e] validate_chain+0x61c/0xb9c\n [\u003cc0458dba\u003e] __lock_acquire+0x723/0x789\n [\u003cc0458eb0\u003e] lock_acquire+0x90/0xa7\n [\u003cc053a990\u003e] ? blkiocg_weight_write+0x82/0x9e\n [\u003cc06929fd\u003e] _raw_spin_lock+0x1e/0x4e\n [\u003cc053a990\u003e] ? blkiocg_weight_write+0x82/0x9e\n [\u003cc053a990\u003e] blkiocg_weight_write+0x82/0x9e\n [\u003cc0467f1e\u003e] cgroup_file_write+0xc6/0x1c0\n [\u003cc0454df5\u003e] ? trace_hardirqs_off+0xb/0xd\n [\u003cc044d93a\u003e] ? cpu_clock+0x2e/0x44\n [\u003cc050e6ec\u003e] ? security_file_permission+0xf/0x11\n [\u003cc04bcdda\u003e] ? rw_verify_area+0x8a/0xad\n [\u003cc0467e58\u003e] ? cgroup_file_write+0x0/0x1c0\n [\u003cc04bd2f3\u003e] vfs_write+0x8c/0x116\n [\u003cc04bd7c6\u003e] sys_write+0x3b/0x60\n [\u003cc04027cc\u003e] sysenter_do_call+0x12/0x32\n\nTo prevent deadlock, we should take locks as following sequence:\n\nblkio_list_lock -\u003e queue_lock -\u003e  blkcg_lock.\n\nThe following patch should fix this bug.\n\nSigned-off-by: Gui Jianfeng \u003cguijianfeng@cn.fujitsu.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "875feb63b9567442be73efbcc9a8470e376d6423",
      "tree": "554331e9634a5327daa755bb1b3338697866018b",
      "parents": [
        "7af92f8754b87bc78cbfd447d5f4096b25c46682"
      ],
      "author": {
        "name": "Divyesh Shah",
        "email": "dpshah@google.com",
        "time": "Wed Jan 06 18:58:20 2010 -0800"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Mon Jan 11 16:16:18 2010 +0100"
      },
      "message": "cfq-iosched: Respect ioprio_class when preempting\n\nIn cfq_should_preempt(), we currently allow some cases where a non-RT request\ncan preempt an ongoing RT cfqq timeslice. This should not happen.\nExamples include:\n\no A sync_noidle wl type non-RT request pre-empting a sync_noidle wl type cfqq\n  on which we are idling.\no Once we have per-cgroup async queues, a non-RT sync request pre-empting a RT\n  async cfqq.\n\nSigned-off-by: Divyesh Shah\u003cdpshah@google.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "ce289321b7dc1eb108e3df0dec872b7429ef49f7",
      "tree": "9153bc19d805d796b7a9ddac04d2d060a9d3261e",
      "parents": [
        "b27d7f16d3c6c27345d4280a739809c1c2c4c0b5"
      ],
      "author": {
        "name": "Kirill Afonshin",
        "email": "kirill_nnov@mail.ru",
        "time": "Fri Jan 08 22:09:59 2010 +0300"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Mon Jan 11 14:29:20 2010 +0100"
      },
      "message": "block: removed unused as_io_context\n\nIt isn\u0027t used anymore, since AS was deleted.\n\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "17be8c245054b9c7786545af3ba3ca4e54cd4ad9",
      "tree": "563687812bbb1b08643dfcc25997e34eb22a71b5",
      "parents": [
        "dd3d145d49c5816b79acc6761ebbd842bc50b0ee"
      ],
      "author": {
        "name": "Martin K. Petersen",
        "email": "martin.petersen@oracle.com",
        "time": "Mon Jan 11 03:21:49 2010 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Mon Jan 11 14:29:20 2010 +0100"
      },
      "message": "block: bdev_stack_limits wrapper\n\nDM does not want to know about partition offsets.  Add a partition-aware\nwrapper that DM can use when stacking block devices.\n\nSigned-off-by: Martin K. Petersen \u003cmartin.petersen@oracle.com\u003e\nAcked-by: Mike Snitzer \u003csnitzer@redhat.com\u003e\nReviewed-by: Alasdair G Kergon \u003cagk@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "dd3d145d49c5816b79acc6761ebbd842bc50b0ee",
      "tree": "107bdb2f46c6aa6bc482909d7ebdbb1da40b7b4f",
      "parents": [
        "fe0b393f2c0a0d23a9bc9ed7dc51a1ee511098bd"
      ],
      "author": {
        "name": "Martin K. Petersen",
        "email": "martin.petersen@oracle.com",
        "time": "Mon Jan 11 03:21:48 2010 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Mon Jan 11 14:29:19 2010 +0100"
      },
      "message": "block: Fix discard alignment calculation and printing\n\nDiscard alignment reporting for partitions was incorrect.  Update to\nmatch the algorithm used elsewhere.\n\nThe alignment can be negative (misaligned).  Fix format string\naccordingly.\n\nSigned-off-by: Martin K. Petersen \u003cmartin.petersen@oracle.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "fe0b393f2c0a0d23a9bc9ed7dc51a1ee511098bd",
      "tree": "557e3d8583bf9cebb127066f0c5487691c3f786b",
      "parents": [
        "c1152949bbdfddf8fc857a883294461d757d5332"
      ],
      "author": {
        "name": "Martin K. Petersen",
        "email": "martin.petersen@oracle.com",
        "time": "Mon Jan 11 03:21:47 2010 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Mon Jan 11 14:29:19 2010 +0100"
      },
      "message": "block: Correct handling of bottom device misaligment\n\nThe top device misalignment flag would not be set if the added bottom\ndevice was already misaligned as opposed to causing a stacking failure.\n\nAlso massage the reporting so that an error is only returned if adding\nthe bottom device caused the misalignment.  I.e. don\u0027t return an error\nif the top is already flagged as misaligned.\n\nSigned-off-by: Martin K. Petersen \u003cmartin.petersen@oracle.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "e79e95db5cffb2e01170d510686489c40937faa1",
      "tree": "b21b0f4be2edf79f3e68c628c3022cda6a72e949",
      "parents": [
        "81744ee44ab2845c16ffd7d6f762f7b4a49a4750"
      ],
      "author": {
        "name": "OGAWA Hirofumi",
        "email": "hirofumi@mail.parknet.co.jp",
        "time": "Tue Dec 29 08:53:54 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Dec 29 08:53:54 2009 +0100"
      },
      "message": "block: Honor the gfp_mask for alloc_page() in blkdev_issue_discard()\n\nSigned-off-by: OGAWA Hirofumi \u003chirofumi@mail.parknet.co.jp\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "81744ee44ab2845c16ffd7d6f762f7b4a49a4750",
      "tree": "c3d0cca0e71080ecd8423cef8af1c632fc444764",
      "parents": [
        "2f7a2d89a8b5915d89ad9ebeb0065db7d5831cea"
      ],
      "author": {
        "name": "Martin K. Petersen",
        "email": "martin.petersen@oracle.com",
        "time": "Tue Dec 29 08:35:35 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Dec 29 08:35:35 2009 +0100"
      },
      "message": "block: Fix incorrect alignment offset reporting and update documentation\n\nqueue_sector_alignment_offset returned the wrong value which caused\npartitions to report an incorrect alignment_offset.  Since offset\nalignment calculation is needed several places it has been split into a\nseparate helper function.  The topology stacking function has been\nupdated accordingly.\n\nFurthermore, comments have been added to clarify how the stacking\nfunction works.\n\nSigned-off-by: Martin K. Petersen \u003cmartin.petersen@oracle.com\u003e\nTested-by: Mike Snitzer \u003csnitzer@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "2f7a2d89a8b5915d89ad9ebeb0065db7d5831cea",
      "tree": "776c4a7e47b07437c30411d7324b5a1c7de01696",
      "parents": [
        "6ec1480d8539c8e2e6ba7fbbeffe5adc640bfe98"
      ],
      "author": {
        "name": "Shaohua Li",
        "email": "shaohua.li@intel.com",
        "time": "Mon Dec 28 13:18:44 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Mon Dec 28 13:18:44 2009 +0100"
      },
      "message": "cfq-iosched: don\u0027t regard requests with long distance as close\n\nseek_mean could be very big sometimes, using it as close criteria is meaningless\nas this doen\u0027t improve any performance. So if it\u0027s big, let\u0027s fallback to\ndefault value.\n\nReviewed-by: Corrado Zoccolo \u003cczoccolo@gmail.com\u003e\nSigned-off-by: Shaohua Li\u003cshaohua.li@intel.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "9504e0864b58b4a304820dcf3755f1da80d5e72f",
      "tree": "1e5bc5e7b2c57b343fab13709178be3aff6f477e",
      "parents": [
        "65b32a573eefa1cdd3cbe5ea59326308e6c3b9ad"
      ],
      "author": {
        "name": "Martin K. Petersen",
        "email": "martin.petersen@oracle.com",
        "time": "Mon Dec 21 15:55:51 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Mon Dec 21 15:55:51 2009 +0100"
      },
      "message": "block: Fix topology stacking for data and discard alignment\n\nThe stacking code incorrectly scaled up the data offset in some cases\ncausing misaligned devices to report alignment.  Rewrite the stacking\nalgorithm to remedy this and apply the same alignment principles to the\ndiscard handling.\n\nSigned-off-by: Martin K. Petersen \u003cmartin.petersen@oracle.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "65b32a573eefa1cdd3cbe5ea59326308e6c3b9ad",
      "tree": "bdcca029d184056ffc9eab0a9c0b95cdf123c9fb",
      "parents": [
        "fb104db41e6e006c85ce1097f372cd1e10c1755c"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Wed Dec 16 17:52:59 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Fri Dec 18 12:40:21 2009 +0100"
      },
      "message": "cfq-iosched: Remove prio_change logic for workload selection\n\no CFQ now internally divides cfq queues in therr workload categories. sync-idle,\n  sync-noidle and async. Which workload to run depends primarily on rb_key\n  offset across three service trees. Which is a combination of mulitiple things\n  including what time queue got queued on the service tree.\n\n  There is one exception though. That is if we switched the prio class, say\n  we served some RT tasks and again started serving BE class, then with-in\n  BE class we always started with sync-noidle workload irrespective of rb_key\n  offset in service trees.\n\n  This can provide better latencies for sync-noidle workload in the presence\n  of RT tasks.\n\no This patch gets rid of that exception and which workload to run with-in\n  class always depends on lowest rb_key across service trees. The reason\n  being that now we have multiple BE class groups and if we always switch\n  to sync-noidle workload with-in group, we can potentially starve a sync-idle\n  workload with-in group. Same is true for async workload which will be in\n  root group. Also the workload-switching with-in group will become very\n  unpredictable as it now depends whether some RT workload was running in\n  the system or not.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nReviewed-by: Gui Jianfeng \u003cguijianfeng@cn.fujitsu.com\u003e\nAcked-by: Corrado Zoccolo \u003cczoccolo@gmail.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "fb104db41e6e006c85ce1097f372cd1e10c1755c",
      "tree": "b769fd161d325f959e3c2c36116c5eb2f0e29f00",
      "parents": [
        "1db32c40600437c5e049796bd32f49f61244c6ef"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Wed Dec 16 17:52:58 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Fri Dec 18 12:40:21 2009 +0100"
      },
      "message": "cfq-iosched: Get rid of nr_groups\n\no Currently code does not seem to be using cfqd-\u003enr_groups. Get rid of it.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nReviewed-by: Gui Jianfeng \u003cguijianfeng@cn.fujitsu.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "1db32c40600437c5e049796bd32f49f61244c6ef",
      "tree": "09f72cf149d7d9034bc3cbcf9597e413c081c5d3",
      "parents": [
        "4a63b030d75a063b910b2bab014d84837cb33eb7"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Wed Dec 16 17:52:57 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Fri Dec 18 12:40:21 2009 +0100"
      },
      "message": "cfq-iosched: Remove the check for same cfq group from allow_merge\n\no allow_merge() already checks if submitting task is pointing to same cfqq\n  as rq has been queued in. If everything is fine, we should not be having\n  a task in one cgroup and having a pointer to cfqq in other cgroup.\n\n  Well I guess in some situations it can happen and that is, when a random\n  IO queue has been moved into root cgroup for group_isolation\u003d0. In\n  this case, tasks\u0027s cgroup/group is different from where actually cfqq is,\n  but this is intentional and in this case merging should be allowed.\n\n  The second situation is where due to close cooperator patches, multiple\n  processes can be sharing a cfqq. If everything implemented right, we should\n  not end up in a situation where tasks from different processes in different\n  groups are sharing the same cfqq as we allow merging of cooperating queues\n  only if they are in same group.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nReviewed-by: Gui Jianfeng \u003cguijianfeng@cn.fujitsu.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "b568be627a7270eba575bc4406a606e1545f91bb",
      "tree": "1afa91fcd56f9ec77ccf1063d79aa2664675c193",
      "parents": [
        "8bea8672edfca7ec5f661cafb218f1205863b343"
      ],
      "author": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Wed Dec 16 09:16:41 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Wed Dec 16 09:16:41 2009 +0100"
      },
      "message": "block: temporarily disable discard granularity\n\nCommit 86b37281411cf1e9bc0a6b5406c45edb7bd9ea5d adds a check for\nmisaligned stacking offsets, but it\u0027s buggy since the defaults are 0.\nHence all dm devices that pass in a non-zero starting offset will\nbe marked as misaligned amd dm will complain.\n\nA real fix is coming, in the mean time disable the discard granularity\ncheck so that users don\u0027t worry about dm reporting about misaligned\ndevices.\n\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "51b736b85155a56543fda8aeca5f8592795d7983",
      "tree": "937c8be978bf66084128cd62fca3e94fa50c3f36",
      "parents": [
        "a8aa1ebdf880ebe7b5738ccebf67e18d62cbdc0b",
        "66ae291978177d5c012015f12b8fbc76dc7d0965"
      ],
      "author": {
        "name": "Linus Torvalds",
        "email": "torvalds@linux-foundation.org",
        "time": "Tue Dec 15 09:11:28 2009 -0800"
      },
      "committer": {
        "name": "Linus Torvalds",
        "email": "torvalds@linux-foundation.org",
        "time": "Tue Dec 15 09:11:28 2009 -0800"
      },
      "message": "Merge branch \u0027for-2.6.33\u0027 of git://git.kernel.dk/linux-2.6-block\n\n* \u0027for-2.6.33\u0027 of git://git.kernel.dk/linux-2.6-block:\n  cfq: set workload as expired if it doesn\u0027t have any slice left\n  Fix a CFQ crash in \"for-2.6.33\" branch of block tree\n  cfq: Remove wait_request flag when idle time is being deleted\n  cfq-iosched: commenting non-obvious initialization\n  cfq-iosched: Take care of corner cases of group losing share due to deletion\n  cfq-iosched: Get rid of cfqq wait_busy_done flag\n  cfq: Optimization for close cooperating queue searching\n  block,xd: Delay allocation of DMA buffers until device is known\n  drbd: Following the hmac change to SHASH (see linux commit 8bd1209cfff)\n  cfq-iosched: reduce write depth only if sync was delayed\n"
    },
    {
      "commit": "66ae291978177d5c012015f12b8fbc76dc7d0965",
      "tree": "1351d66beea2b0b2300a7491ca8d9ffb83578e34",
      "parents": [
        "82bbbf28db4beefcd8b897800153e21378270cd1"
      ],
      "author": {
        "name": "Gui Jianfeng",
        "email": "guijianfeng@cn.fujitsu.com",
        "time": "Tue Dec 15 10:08:45 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Dec 15 10:08:45 2009 +0100"
      },
      "message": "cfq: set workload as expired if it doesn\u0027t have any slice left\n\nWhen a group is resumed, if it doesn\u0027t have workload slice left,\nwe should set workload_expires as expired. Otherwise, we might\nstart from where we left in previous group by error.\nThanks the idea from Corrado.\n\nSigned-off-by: Gui Jianfeng \u003cguijianfeng@cn.fujitsu.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "82bbbf28db4beefcd8b897800153e21378270cd1",
      "tree": "3e8a437711010c14d2e9e88dcf29afcfecf7ba9a",
      "parents": [
        "554554f60ad619e1efab01897208bc320b81d9da"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 10 19:25:41 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 10 19:25:41 2009 +0100"
      },
      "message": "Fix a CFQ crash in \"for-2.6.33\" branch of block tree\n\nI think my previous patch introduced a bug which can lead to CFQ hitting\nBUG_ON().\n\nThe offending commit in for-2.6.33 branch is.\n\ncommit 7667aa0630407bc07dc38dcc79d29cc0a65553c1\nAuthor: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nDate:   Tue Dec 8 17:52:58 2009 -0500\n\n    cfq-iosched: Take care of corner cases of group losing share due to deletion\n\nWhile doing some stress testing on my box, I enountered following.\n\nlogin: [ 3165.148841] BUG: scheduling while\natomic: swapper/0/0x10000100\n[ 3165.149821] Modules linked in: cfq_iosched dm_multipath qla2xxx igb\nscsi_transport_fc dm_snapshot [last unloaded: scsi_wait_scan]\n[ 3165.149821] Pid: 0, comm: swapper Not tainted\n2.6.32-block-for-33-merged-new #3\n[ 3165.149821] Call Trace:\n[ 3165.149821]  \u003cIRQ\u003e  [\u003cffffffff8103fab8\u003e] __schedule_bug+0x5c/0x60\n[ 3165.149821]  [\u003cffffffff8103afd7\u003e] ? __wake_up+0x44/0x4d\n[ 3165.149821]  [\u003cffffffff8153a979\u003e] schedule+0xe3/0x7bc\n[ 3165.149821]  [\u003cffffffff8103a796\u003e] ? cpumask_next+0x1d/0x1f\n[ 3165.149821]  [\u003cffffffffa000b21d\u003e] ? cfq_dispatch_requests+0x6ba/0x93e\n[cfq_iosched]\n[ 3165.149821]  [\u003cffffffff810422d8\u003e] __cond_resched+0x2a/0x35\n[ 3165.149821]  [\u003cffffffffa000b21d\u003e] ? cfq_dispatch_requests+0x6ba/0x93e\n[cfq_iosched]\n[ 3165.149821]  [\u003cffffffff8153b1ee\u003e] _cond_resched+0x2c/0x37\n[ 3165.149821]  [\u003cffffffff8100e2db\u003e] is_valid_bugaddr+0x16/0x2f\n[ 3165.149821]  [\u003cffffffff811e4161\u003e] report_bug+0x18/0xac\n[ 3165.149821]  [\u003cffffffff8100f1fc\u003e] die+0x39/0x63\n[ 3165.149821]  [\u003cffffffff8153cde1\u003e] do_trap+0x11a/0x129\n[ 3165.149821]  [\u003cffffffff8100d470\u003e] do_invalid_op+0x96/0x9f\n[ 3165.149821]  [\u003cffffffffa000b21d\u003e] ? cfq_dispatch_requests+0x6ba/0x93e\n[cfq_iosched]\n[ 3165.149821]  [\u003cffffffff81034b4d\u003e] ? enqueue_task+0x5c/0x67\n[ 3165.149821]  [\u003cffffffff8103ae83\u003e] ? task_rq_unlock+0x11/0x13\n[ 3165.149821]  [\u003cffffffff81041aae\u003e] ? try_to_wake_up+0x292/0x2a4\n[ 3165.149821]  [\u003cffffffff8100c935\u003e] invalid_op+0x15/0x20\n[ 3165.149821]  [\u003cffffffffa000b21d\u003e] ? cfq_dispatch_requests+0x6ba/0x93e\n[cfq_iosched]\n[ 3165.149821]  [\u003cffffffff810df5a6\u003e] ? virt_to_head_page+0xe/0x2f\n[ 3165.149821]  [\u003cffffffff811d8c2a\u003e] blk_peek_request+0x191/0x1a7\n[ 3165.149821]  [\u003cffffffff811e5b8d\u003e] ? kobject_get+0x1a/0x21\n[ 3165.149821]  [\u003cffffffff812c8d4c\u003e] scsi_request_fn+0x82/0x3df\n[ 3165.149821]  [\u003cffffffff8110b2de\u003e] ? bio_fs_destructor+0x15/0x17\n[ 3165.149821]  [\u003cffffffff810df5a6\u003e] ? virt_to_head_page+0xe/0x2f\n[ 3165.149821]  [\u003cffffffff811d931f\u003e] __blk_run_queue+0x42/0x71\n[ 3165.149821]  [\u003cffffffff811d9403\u003e] blk_run_queue+0x26/0x3a\n[ 3165.149821]  [\u003cffffffff812c8761\u003e] scsi_run_queue+0x2de/0x375\n[ 3165.149821]  [\u003cffffffff812b60ac\u003e] ? put_device+0x17/0x19\n[ 3165.149821]  [\u003cffffffff812c92d7\u003e] scsi_next_command+0x3b/0x4b\n[ 3165.149821]  [\u003cffffffff812c9b9f\u003e] scsi_io_completion+0x1c9/0x3f5\n[ 3165.149821]  [\u003cffffffff812c3c36\u003e] scsi_finish_command+0xb5/0xbe\n\nI think I have hit following BUG_ON() in cfq_dispatch_request().\n\nBUG_ON(RB_EMPTY_ROOT(\u0026cfqq-\u003esort_list));\n\nPlease find attached the patch to fix it. I have done some stress testing\nwith it and have not seen it happening again.\n\no We should wait on a queue even after slice expiry only if it is empty. If\n  queue is not empty then continue to expire it.\n\no If we decide to keep the queue then make cfqq\u003dNULL. Otherwise select_queue()\n  will return a valid cfqq and cfq_dispatch_request() can hit following\n  BUG_ON().\n\n  BUG_ON(RB_EMPTY_ROOT(\u0026cfqq-\u003esort_list))\n\nReviewed-by: Jeff Moyer \u003cjmoyer@redhat.com\u003e\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "554554f60ad619e1efab01897208bc320b81d9da",
      "tree": "b240b0e65dc763c6c2f7b5661f59ad4bcb0385b3",
      "parents": [
        "edc71131c4dc6cc73e2a24aa0a7a79cfce738f12"
      ],
      "author": {
        "name": "Gui Jianfeng",
        "email": "guijianfeng@cn.fujitsu.com",
        "time": "Thu Dec 10 09:38:39 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 10 09:38:39 2009 +0100"
      },
      "message": "cfq: Remove wait_request flag when idle time is being deleted\n\nRemove wait_request flag when idle time is being deleted, otherwise\nit\u0027ll hit this path every time when a request is enqueued.\n\nSigned-off-by: Gui Jianfeng \u003cguijianfeng@cn.fujitsu.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "4ef58d4e2ad1fa2a3e5bbf41af2284671fca8cf8",
      "tree": "856ba96302a36014736747e8464f80eeb827bbdd",
      "parents": [
        "f6c4c8195b5e7878823caa1181be404d9e86d369",
        "d014d043869cdc591f3a33243d3481fa4479c2d0"
      ],
      "author": {
        "name": "Linus Torvalds",
        "email": "torvalds@linux-foundation.org",
        "time": "Wed Dec 09 19:43:33 2009 -0800"
      },
      "committer": {
        "name": "Linus Torvalds",
        "email": "torvalds@linux-foundation.org",
        "time": "Wed Dec 09 19:43:33 2009 -0800"
      },
      "message": "Merge branch \u0027for-linus\u0027 of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial\n\n* \u0027for-linus\u0027 of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (42 commits)\n  tree-wide: fix misspelling of \"definition\" in comments\n  reiserfs: fix misspelling of \"journaled\"\n  doc: Fix a typo in slub.txt.\n  inotify: remove superfluous return code check\n  hdlc: spelling fix in find_pvc() comment\n  doc: fix regulator docs cut-and-pasteism\n  mtd: Fix comment in Kconfig\n  doc: Fix IRQ chip docs\n  tree-wide: fix assorted typos all over the place\n  drivers/ata/libata-sff.c: comment spelling fixes\n  fix typos/grammos in Documentation/edac.txt\n  sysctl: add missing comments\n  fs/debugfs/inode.c: fix comment typos\n  sgivwfb: Make use of ARRAY_SIZE.\n  sky2: fix sky2_link_down copy/paste comment error\n  tree-wide: fix typos \"couter\" -\u003e \"counter\"\n  tree-wide: fix typos \"offest\" -\u003e \"offset\"\n  fix kerneldoc for set_irq_msi()\n  spidev: fix double \"of of\" in comment\n  comment typo fix: sybsystem -\u003e subsystem\n  ...\n"
    },
    {
      "commit": "edc71131c4dc6cc73e2a24aa0a7a79cfce738f12",
      "tree": "b568734b3f053be12f0dabcf2ceea1049537cea1",
      "parents": [
        "7667aa0630407bc07dc38dcc79d29cc0a65553c1"
      ],
      "author": {
        "name": "Corrado Zoccolo",
        "email": "czoccolo@gmail.com",
        "time": "Wed Dec 09 20:56:04 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Wed Dec 09 20:56:04 2009 +0100"
      },
      "message": "cfq-iosched: commenting non-obvious initialization\n\nAdded a comment to explain the initialization of last_delayed_sync.\n\nSigned-off-by: Corrado Zoccolo \u003cczoccolo@gmail.com\u003e\nAcked-by: Jeff Moyer \u003cjmoyer@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "7667aa0630407bc07dc38dcc79d29cc0a65553c1",
      "tree": "cd9007b2dfebec215d955952ea0f9914490bddaa",
      "parents": [
        "c244bb50a9baa2ec47a458bbafb36b5e559ed5fa"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Tue Dec 08 17:52:58 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Wed Dec 09 15:11:04 2009 +0100"
      },
      "message": "cfq-iosched: Take care of corner cases of group losing share due to deletion\n\nIf there is a sequential reader running in a group, we wait for next request\nto come in that group after slice expiry and once new request is in, we expire\nthe queue. Otherwise we delete the group from service tree and group looses\nits fair share.\n\nSo far I was marking a queue as wait_busy if it had consumed its slice and\nit was last queue in the group. But this condition did not cover following\ntwo cases.\n\n1.If a request completed and slice has not expired yet. Next request comes\n  in and is dispatched to disk. Now select_queue() hits and slice has expired.\n  This group will be deleted. Because request is still in the disk, this queue\n  will never get a chance to wait_busy.\n\n2.If request completed and slice has not expired yet. Before next request\n  comes in (delay due to think time), select_queue() hits and expires the\n  queue hence group. This queue never got a chance to wait busy.\n\nGui was hitting the boundary condition 1 and not getting fairness numbers\nproportional to weight.\n\nThis patch puts the checks for above two conditions and improves the fairness\nnumbers for sequential workload on rotational media. Check in select_queue()\ntakes care of case 1 and additional check in should_wait_busy() takes care\nof case 2.\n\nReported-by: Gui Jianfeng \u003cguijianfeng@cn.fujitsu.com\u003e\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "c244bb50a9baa2ec47a458bbafb36b5e559ed5fa",
      "tree": "946c9c87e21055ff371a05710c7a0bcf71bdcc18",
      "parents": [
        "b9d8f4c73b1af4cfd53f819bf84c2bce31232275"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Tue Dec 08 17:52:57 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Wed Dec 09 15:11:03 2009 +0100"
      },
      "message": "cfq-iosched: Get rid of cfqq wait_busy_done flag\n\no Get rid of wait_busy_done flag. This flag only tells we were doing wait\n  busy on a queue and that queue got request so expire it. That information\n  can easily be obtained by (cfq_cfqq_wait_busy() \u0026\u0026 queue_is_not_empty). So\n  remove this flag and keep code simple.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "b9d8f4c73b1af4cfd53f819bf84c2bce31232275",
      "tree": "2ae92bc6cabfd9d2308902c3ac92f04fe6fbf1fb",
      "parents": [
        "a3b8d92d25212c5b6534ae9b347ed2858de78336"
      ],
      "author": {
        "name": "Gui Jianfeng",
        "email": "guijianfeng@cn.fujitsu.com",
        "time": "Tue Dec 08 08:54:17 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Wed Dec 09 15:11:03 2009 +0100"
      },
      "message": "cfq: Optimization for close cooperating queue searching\n\nIt doesn\u0027t make any sense to try to find out a close cooperating\nqueue if current cfqq is the only one in the group.\n\nSigned-off-by: Gui Jianfeng \u003cguijianfeng@cn.fujitsu.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "573412b29586e58477adb70e022193a337763319",
      "tree": "757ebcc4da3ba7b8d8beb8e8e0ff6a4fe4428f52",
      "parents": [
        "2b876f95d03e226394b5d360c86127cbefaf614b"
      ],
      "author": {
        "name": "Corrado Zoccolo",
        "email": "czoccolo@gmail.com",
        "time": "Sun Dec 06 11:48:52 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "axboe@carl.(none)",
        "time": "Wed Dec 09 12:32:55 2009 +0100"
      },
      "message": "cfq-iosched: reduce write depth only if sync was delayed\n\nThe introduction of ramp-up formula for async queue depths has\nslowed down dirty page reclaim, by reducing async write performance.\nThis patch makes sure the formula kicks in only when sync request\nwas recently delayed.\n\nSigned-off-by: Corrado Zoccolo \u003cczoccolo@gmail.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "878eaddd05d251cefa9632c2b8046833c5eead66",
      "tree": "a5bf9b6c1856969ff7a7cd0d676ea2b419072103",
      "parents": [
        "accee7854b378a8ab5995d8f5dc5d8abc3b3d23a"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Mon Dec 07 19:37:15 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "axboe@carl.(none)",
        "time": "Mon Dec 07 19:37:15 2009 +0100"
      },
      "message": "cfq-iosched: Do not access cfqq after freeing it\n\nFix a crash during boot reported by Jeff Moyer. Fix the issue of accessing\ncfqq after freeing it.\n\nReported-by: Jeff Moyer \u003cjmoyer@redhat.com\u003e\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nReviewed-by: Jeff Moyer \u003cjmoyer@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003caxboe@carl.(none)\u003e\n"
    },
    {
      "commit": "accee7854b378a8ab5995d8f5dc5d8abc3b3d23a",
      "tree": "431c8bc6fbe4afca06eb1ac16c06f1ce388d7a5c",
      "parents": [
        "bb729bc98c0f3e6a898d8730df3e2830bf68751a"
      ],
      "author": {
        "name": "Stephen Rothwell",
        "email": "sfr@canb.auug.org.au",
        "time": "Mon Dec 07 19:29:39 2009 +1100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Mon Dec 07 09:47:07 2009 +0100"
      },
      "message": "block: include linux/err.h to use ERR_PTR\n\nSigned-off-by: Stephen Rothwell \u003csfr@canb.auug.org.au\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "bb729bc98c0f3e6a898d8730df3e2830bf68751a",
      "tree": "f2170f8f688a7c7f813168a6c8c757087934c094",
      "parents": [
        "846954b0a32f4ae953e082eabd178e7a98dd2efd"
      ],
      "author": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Sun Dec 06 09:54:19 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Sun Dec 06 09:54:19 2009 +0100"
      },
      "message": "cfq-iosched: use call_rcu() instead of doing grace period stall on queue exit\n\nAfter the merge of the IO controller patches, booting on my megaraid\nbox ran much slower. Vivek Goyal traced it down to megaraid discovery\ncreating tons of devices, each suffering a grace period when they later\nkill that queue (if no device is found).\n\nSo lets use call_rcu() to batch these deferred frees, instead of taking\nthe grace period hit for each one.\n\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "846954b0a32f4ae953e082eabd178e7a98dd2efd",
      "tree": "a1a82fab930341d275a469d4368cf89e596aa112",
      "parents": [
        "3e2520668970aab5a764044a298e987aafc1f63d"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Fri Dec 04 10:36:43 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Fri Dec 04 16:38:14 2009 +0100"
      },
      "message": "blkio: Allow CFQ group IO scheduling even when CFQ is a module\n\no Now issues of blkio controller and CFQ in module mode should be fixed.\n  Enable the cfq group scheduling support in module mode.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "3e2520668970aab5a764044a298e987aafc1f63d",
      "tree": "088ebf7c4576d597774c8c332bab590dc3a472d6",
      "parents": [
        "9d6a986c0b276085f7944cd8ad65f4f82aff7536"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Fri Dec 04 10:36:42 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Fri Dec 04 16:38:14 2009 +0100"
      },
      "message": "blkio: Implement dynamic io controlling policy registration\n\no One of the goals of block IO controller is that it should be able to\n  support mulitple io control policies, some of which be operational at\n  higher level in storage hierarchy.\n\no To begin with, we had one io controlling policy implemented by CFQ, and\n  I hard coded the CFQ functions called by blkio. This created issues when\n  CFQ is compiled as module.\n\no This patch implements a basic dynamic io controlling policy registration\n  functionality in blkio. This is similar to elevator functionality where\n  ioschedulers register the functions dynamically.\n\no Now in future, when more IO controlling policies are implemented, these\n  can dynakically register with block IO controller.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "9d6a986c0b276085f7944cd8ad65f4f82aff7536",
      "tree": "1e72c813f4346ee329d5d427e214d183af78934f",
      "parents": [
        "b69f2292063d2caf37ca9aec7d63ded203701bf3"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Fri Dec 04 10:36:41 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Fri Dec 04 16:38:14 2009 +0100"
      },
      "message": "blkio: Export some symbols from blkio as its user CFQ can be a module\n\no blkio controller is inside the kernel and cfq makes use of interfaces\n  exported by blkio. CFQ can be a module too, hence export symbols used\n  by CFQ.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "b69f2292063d2caf37ca9aec7d63ded203701bf3",
      "tree": "be4acb81ea4ab7014047808ec2b2c908e8334f55",
      "parents": [
        "61cc74fbb87af6aa551a06a370590c9bc07e29d9"
      ],
      "author": {
        "name": "Louis Rilling",
        "email": "louis.rilling@kerlabs.com",
        "time": "Fri Dec 04 14:52:42 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Fri Dec 04 16:36:18 2009 +0100"
      },
      "message": "block: Fix io_context leak after failure of clone with CLONE_IO\n\nWith CLONE_IO, parent\u0027s io_context-\u003enr_tasks is incremented, but never\ndecremented whenever copy_process() fails afterwards, which prevents\nexit_io_context() from calling IO schedulers exit functions.\n\nGive a task_struct to exit_io_context(), and call exit_io_context() instead of\nput_io_context() in copy_process() cleanup path.\n\nSigned-off-by: Louis Rilling \u003clouis.rilling@kerlabs.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "61cc74fbb87af6aa551a06a370590c9bc07e29d9",
      "tree": "351116a74bba13b016c730f777eca86b3b197e5e",
      "parents": [
        "3c764b7a654668dd04905841d6024f7b6aa843a5"
      ],
      "author": {
        "name": "Louis Rilling",
        "email": "louis.rilling@kerlabs.com",
        "time": "Fri Dec 04 14:52:41 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Fri Dec 04 16:36:18 2009 +0100"
      },
      "message": "block: Fix io_context leak after clone with CLONE_IO\n\nWith CLONE_IO, copy_io() increments both ioc-\u003erefcount and ioc-\u003enr_tasks.\nHowever exit_io_context() only decrements ioc-\u003erefcount if ioc-\u003enr_tasks\nreaches 0.\n\nAlways call put_io_context() in exit_io_context().\n\nSigned-off-by: Louis Rilling \u003clouis.rilling@kerlabs.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "af901ca181d92aac3a7dc265144a9081a86d8f39",
      "tree": "380054af22521144fbe1364c3bcd55ad24c9bde4",
      "parents": [
        "972b94ffb90ea6d20c589d9a47215df103388ddd"
      ],
      "author": {
        "name": "André Goddard Rosa",
        "email": "andre.goddard@gmail.com",
        "time": "Sat Nov 14 13:09:05 2009 -0200"
      },
      "committer": {
        "name": "Jiri Kosina",
        "email": "jkosina@suse.cz",
        "time": "Fri Dec 04 15:39:55 2009 +0100"
      },
      "message": "tree-wide: fix assorted typos all over the place\n\nThat is \"success\", \"unknown\", \"through\", \"performance\", \"[re|un]mapping\"\n, \"access\", \"default\", \"reasonable\", \"[con]currently\", \"temperature\"\n, \"channel\", \"[un]used\", \"application\", \"example\",\"hierarchy\", \"therefore\"\n, \"[over|under]flow\", \"contiguous\", \"threshold\", \"enough\" and others.\n\nSigned-off-by: André Goddard Rosa \u003candre.goddard@gmail.com\u003e\nSigned-off-by: Jiri Kosina \u003cjkosina@suse.cz\u003e\n"
    },
    {
      "commit": "3c764b7a654668dd04905841d6024f7b6aa843a5",
      "tree": "68b7c611f5e98bab3c781ecc775a0ecf46c43b61",
      "parents": [
        "237e5bc4e51813e9d8ba9da0f63e7acc608882d7"
      ],
      "author": {
        "name": "Shaohua Li",
        "email": "shaohua.li@intel.com",
        "time": "Fri Dec 04 13:12:06 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Fri Dec 04 13:12:06 2009 +0100"
      },
      "message": "cfq-iosched: make nonrot check logic consistent\n\ncfq_arm_slice_timer() has logic to disable idle window for SSD device. The same\nthing should be done at cfq_select_queue() too, otherwise we will still see\nidle window. This makes the nonrot check logic consistent in cfq.\nTests in a intel SSD with low_latency knob close, below patch can triple disk\nthoughput for muti-thread sequential read.\n\nSigned-off-by: Shaohua Li \u003cshaohua.li@intel.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "237e5bc4e51813e9d8ba9da0f63e7acc608882d7",
      "tree": "7528d2c306c9fe4117a7969e801f182f5245a232",
      "parents": [
        "f2eecb91522686edf8199947b77f435a4031d92f"
      ],
      "author": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Fri Dec 04 10:07:38 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Fri Dec 04 10:07:38 2009 +0100"
      },
      "message": "io controller: quick fix for blk-cgroup and modular CFQ\n\nIt\u0027s currently not an allowed configuration, so express that in Kconfig.\n\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "f2eecb91522686edf8199947b77f435a4031d92f",
      "tree": "e584c9d81971fb741508c176d74ef51ff45a4bcc",
      "parents": [
        "2f5ea47712489a9d2d3cb832eb06062e4e64e0ec"
      ],
      "author": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Fri Dec 04 10:06:35 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Fri Dec 04 10:06:35 2009 +0100"
      },
      "message": "cfq-iosched: move IO controller declerations to a header file\n\nThey should not be declared inside some other file that\u0027s not related\nto CFQ.\n\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "2f5ea47712489a9d2d3cb832eb06062e4e64e0ec",
      "tree": "49c943cf46b83b4fc7da1a38d65cc7914e8ddbfb",
      "parents": [
        "72f924f62a6eb375c7c237ecc911f95be0531d1a"
      ],
      "author": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 21:06:43 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 21:07:17 2009 +0100"
      },
      "message": "cfq-iosched: fix compile problem with !CONFIG_CGROUP\n\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "c04645e592d4dd60c58def40c913699d4c806727",
      "tree": "61e2b6fac3c9dd0f211c07f024fe5cb17ff5d3cf",
      "parents": [
        "ae30c286553c91c49af5cbc0265a05a6543d0c52"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 03 12:59:56 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 19:28:53 2009 +0100"
      },
      "message": "blkio: Wait on sync-noidle queue even if rq_noidle \u003d 1\n\no rq_noidle() is supposed to tell cfq that do not expect a request after this\n  one, hence don\u0027t idle. But this does not seem to work very well. For example\n  for direct random readers, rq_noidle \u003d 1 but there is next request coming\n  after this. Not idling, leads to a group not getting its share even if\n  group_isolation\u003d1.\n\no The right solution for this issue is to scan the higher layers and set\n  right flag (WRITE_SYNC or WRITE_ODIRECT). For the time being, this single\n  line fix helps. This should not have any significant impact when we are\n  not using cgroups. I will later figure out IO paths in higher layer and\n  fix it.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "ae30c286553c91c49af5cbc0265a05a6543d0c52",
      "tree": "1dcb055e156ca9190d0da5bccf32a3a166e12d52",
      "parents": [
        "f26bd1f0a3a31bc5e16d285f5e1b00a56abf6238"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 03 12:59:55 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 19:28:53 2009 +0100"
      },
      "message": "blkio: Implement group_isolation tunable\n\no If a group is running only a random reader, then it will not have enough\n  traffic to keep disk busy and we will reduce overall throughput. This\n  should result in better latencies for random reader though. If we don\u0027t\n  idle on random reader service tree, then this random reader will experience\n  large latencies if there are other groups present in system with sequential\n  readers running in these.\n\no One solution suggested by corrado is that by default keep the random readers\n  or sync-noidle workload in root group so that during one dispatch round\n  we idle only once on sync-noidle tree. This means that all the sync-idle\n  workload queues will be in their respective group and we will see service\n  differentiation in those but not on sync-noidle workload.\n\no Provide a tunable group_isolation. If set, this will make sure that even\n  sync-noidle queues go in their respective group and we wait on these. This\n  provides stronger isolation between groups but at the expense of throughput\n  if group does not have enough traffic to keep the disk busy.\n\no By default group_isolation \u003d 0\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "f26bd1f0a3a31bc5e16d285f5e1b00a56abf6238",
      "tree": "8e49302c146eacdd1cfbe78a6bd3aad2b81c3050",
      "parents": [
        "f75edf2dc828802d358393be80a6c89e919f8273"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 03 12:59:54 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 19:28:53 2009 +0100"
      },
      "message": "blkio: Determine async workload length based on total number of queues\n\no Async queues are not per group. Instead these are system wide and maintained\n  in root group. Hence their workload slice length should be calculated\n  based on total number of queues in the system and not just queues in the\n  root group.\n\no As root group\u0027s default weight is 1000, make sure to charge async queue\n  more in terms of vtime so that it does not get more time on disk because\n  root group has higher weight.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "f75edf2dc828802d358393be80a6c89e919f8273",
      "tree": "a3b2fb05298ea41ecc0fd7ad56e1218369f7f9fd",
      "parents": [
        "f8d461d692c341add957fb973fb5ee1f62039dc7"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 03 12:59:53 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 19:28:53 2009 +0100"
      },
      "message": "blkio: Wait for cfq queue to get backlogged if group is empty\n\no If a queue consumes its slice and then gets deleted from service tree, its\n  associated group will also get deleted from service tree if this was the\n  only queue in the group. That will make group loose its share.\n\no For the queues on which we have idling on and if these have used their\n  slice, wait a bit for these queues to get backlogged again and then\n  expire these queues so that group does not loose its share.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "f8d461d692c341add957fb973fb5ee1f62039dc7",
      "tree": "42c6cf987aa4d38b271a60d2b62e92c6c748cd69",
      "parents": [
        "24610333d578478d354144ab4709a203684afc5f"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 03 12:59:52 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 19:28:53 2009 +0100"
      },
      "message": "blkio: Propagate cgroup weight updation to cfq groups\n\no Propagate blkio cgroup weight updation to associated cfq groups.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "24610333d578478d354144ab4709a203684afc5f",
      "tree": "d258c695cfa320845212f71e8900af4d90538d6b",
      "parents": [
        "8682e1f15f26dae9a9e8af794d179055fbd81166"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 03 12:59:51 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 19:28:52 2009 +0100"
      },
      "message": "blkio: Drop the reference to queue once the task changes cgroup\n\no If a task changes cgroup, drop reference to the cfqq associated with io\n  context and set cfqq pointer stored in ioc to NULL so that upon next request\n  arrival we will allocate a  new queue in new group.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "8682e1f15f26dae9a9e8af794d179055fbd81166",
      "tree": "d6e87631f91527656490df9b28be107fb5e974b0",
      "parents": [
        "220841906fccafaf4094e87bdb6d252e20cf8c7c"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 03 12:59:50 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 19:28:52 2009 +0100"
      },
      "message": "blkio: Provide some isolation between groups\n\no Do not allow following three operations across groups for isolation.\n\t- selection of co-operating queues\n\t- preemtpions across groups\n\t- request merging across groups.\n\no Async queues are currently global and not per group. Allow preemption of\n  an async queue if a sync queue in other group gets backlogged.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "220841906fccafaf4094e87bdb6d252e20cf8c7c",
      "tree": "f25b1f057887cf2a05bb8309e0b757149e052797",
      "parents": [
        "2868ef7b39490e6b41c2c61cd9a5cd891e778b54"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 03 12:59:49 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 19:28:52 2009 +0100"
      },
      "message": "blkio: Export disk time and sectors used by a group to user space\n\no Export disk time and sector used by a group to user space through cgroup\n  interface.\n\no Also export a \"dequeue\" interface to cgroup which keeps track of how many\n  a times a group was deleted from service tree. Helps in debugging.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "2868ef7b39490e6b41c2c61cd9a5cd891e778b54",
      "tree": "e50e169e984d8bd201de2f73f98e31a65c028feb",
      "parents": [
        "b1c3576961847da26c91b1e97f226bb66be5fa3f"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 03 12:59:48 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 19:28:52 2009 +0100"
      },
      "message": "blkio: Some debugging aids for CFQ\n\no Some debugging aids for CFQ.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "b1c3576961847da26c91b1e97f226bb66be5fa3f",
      "tree": "e228525220031232463f9cbbe017bad67807e6d4",
      "parents": [
        "25fb5169d4c9d4255107abbb7c08ab712434efc8"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 03 12:59:47 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 19:28:52 2009 +0100"
      },
      "message": "blkio: Take care of cgroup deletion and cfq group reference counting\n\no One can choose to change elevator or delete a cgroup. Implement group\n  reference counting so that both elevator exit and cgroup deletion can\n  take place gracefully.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Nauman Rafique \u003cnauman@google.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "25fb5169d4c9d4255107abbb7c08ab712434efc8",
      "tree": "8939bd6f73f9888d954672dfaac1cc25e313cb2f",
      "parents": [
        "dae739ebc4c590630039533a5bbd05865966094f"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 03 12:59:46 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 19:28:52 2009 +0100"
      },
      "message": "blkio: Dynamic cfq group creation based on cgroup tasks belongs to\n\no Determine the cgroup IO submitting task belongs to and create the cfq\n  group if it does not exist already.\n\no Also link cfqq and associated cfq group.\n\no Currently all async IO is mapped to root group.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "dae739ebc4c590630039533a5bbd05865966094f",
      "tree": "005f98ed4c4302ea71b48ad6a074fa6ff714df4a",
      "parents": [
        "58ff82f34cded3812af5b6c69b6aa626b6be2490"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 03 12:59:45 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 19:28:52 2009 +0100"
      },
      "message": "blkio: Group time used accounting and workload context save restore\n\no This patch introduces the functionality to do the accounting of group time\n  when a queue expires. This time used decides which is the group to go\n  next.\n\no Also introduce the functionlity to save and restore the workload type\n  context with-in group. It might happen that once we expire the cfq queue\n  and group, a different group will schedule in and we will lose the context\n  of the workload type. Hence save and restore it upon queue expiry.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "58ff82f34cded3812af5b6c69b6aa626b6be2490",
      "tree": "06098474c5763f20d1c9715faf67c83c56b9a787",
      "parents": [
        "25bc6b07767fe77422312eda2af99c9477f76191"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 03 12:59:44 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 19:28:52 2009 +0100"
      },
      "message": "blkio: Implement per cfq group latency target and busy queue avg\n\no So far we had 300ms soft target latency system wide. Now with the\n  introduction of cfq groups, divide that latency by number of groups so\n  that one can come up with group target latency which will be helpful\n  in determining the workload slice with-in group and also the dynamic\n  slice length of the cfq queue.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "25bc6b07767fe77422312eda2af99c9477f76191",
      "tree": "1e0f2d5a18efb63c651df8773a6d5ad2b87d7687",
      "parents": [
        "31e4c28d95e64f2d5d3c497a3ecf37c62de635b4"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 03 12:59:43 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 19:28:52 2009 +0100"
      },
      "message": "blkio: Introduce per cfq group weights and vdisktime calculations\n\no Bring in the per cfq group weight and how vdisktime is calculated for the\n  group. Also bring in the functionality of updating the min_vdisktime of\n  the group service tree.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "31e4c28d95e64f2d5d3c497a3ecf37c62de635b4",
      "tree": "ffbb99b2565c4bdd4921fd7077164e7fc295b2bc",
      "parents": [
        "1fa8f6d68b5c8ca0a608fd8d296c5f07ac788cd6"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 03 12:59:42 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 19:28:51 2009 +0100"
      },
      "message": "blkio: Introduce blkio controller cgroup interface\n\no This is basic implementation of blkio controller cgroup interface. This is\n  the common interface visible to user space and should be used by different\n  IO control policies as we implement those.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "1fa8f6d68b5c8ca0a608fd8d296c5f07ac788cd6",
      "tree": "1e6d9e0ed1bd61f7f8f71a7191815be2ab65aac3",
      "parents": [
        "f04a64246344ad50e4b4b4186174a0912d07f30b"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 03 12:59:41 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 19:28:51 2009 +0100"
      },
      "message": "blkio: Introduce the root service tree for cfq groups\n\no So far we just had one cfq_group in cfq_data. To create space for more than\n  one cfq_group, we need to have a service tree of groups where all the groups\n  can be queued if they have active cfq queues backlogged in these.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "f04a64246344ad50e4b4b4186174a0912d07f30b",
      "tree": "03d2d39d2811350af39dd635297b90ca52b9b6fe",
      "parents": [
        "615f0259e6940293359a189f4881bb28c2fea40b"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 03 12:59:40 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 19:28:51 2009 +0100"
      },
      "message": "blkio: Keep queue on service tree until we expire it\n\no Currently cfqq deletes a queue from service tree if it is empty (even if\n  we might idle on the queue). This patch keeps the queue on service tree\n  hence associated group remains on the service tree until we decide that\n  we are not going to idle on the queue and expire it.\n\no This just helps in time accounting for queue/group and in implementation\n  of rest of the patches.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "615f0259e6940293359a189f4881bb28c2fea40b",
      "tree": "36ae080bc809a8d998801c0bcfc0d63b7b892745",
      "parents": [
        "cdb16e8f739985b8a5c9f4569b026583bbcd01a5"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 03 12:59:39 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 19:28:51 2009 +0100"
      },
      "message": "blkio: Implement macro to traverse each service tree in group\n\no Implement a macro to traverse each service tree in the group. This avoids\n  usage of double for loop and special condition for idle tree 4 times.\n\no Macro is little twisted because of special handling of idle class service\n  tree.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "cdb16e8f739985b8a5c9f4569b026583bbcd01a5",
      "tree": "860b74f8134cfbd516cc73b8b9a9edfe4e3d2db6",
      "parents": [
        "bf7919371025412978268efca4b09dd847acb395"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 03 12:59:38 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 19:28:51 2009 +0100"
      },
      "message": "blkio: Introduce the notion of cfq groups\n\no This patch introduce the notion of cfq groups. Soon we will can have multiple\n  groups of different weights in the system.\n\no Various service trees (prioclass and workload type trees), will become per\n  cfq group. So hierarchy looks as follows.\n\n\t\t\tcfq_groups\n\t\t\t   |\n\t\t\tworkload type\n\t\t\t   |\n\t\t        cfq queue\n\no When an scheduling decision has to be taken, first we select the cfq group\n  then workload with-in the group and then cfq queue with-in the workload\n  type.\n\no This patch just makes various workload service tree per cfq group and\n  introduce the function to be able to choose a group for scheduling.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "bf7919371025412978268efca4b09dd847acb395",
      "tree": "f6144bf301f00f53f150f4213928f063232faaa1",
      "parents": [
        "753c89130c52b96e66e5ceff19bd1336de9a5ce8"
      ],
      "author": {
        "name": "Vivek Goyal",
        "email": "vgoyal@redhat.com",
        "time": "Thu Dec 03 12:59:37 2009 -0500"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 19:28:51 2009 +0100"
      },
      "message": "blkio: Set must_dispatch only if we decided to not dispatch the request\n\no must_dispatch flag should be set only if we decided not to run the queue\n  and dispatch the request.\n\nSigned-off-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "474b18ccc264c472abeec50f48469b6477202699",
      "tree": "77c9f33d65b78266560b3aa0bea1c7d16fb45b2e",
      "parents": [
        "98262f2762f0067375f83824d81ea929e37e6bfe"
      ],
      "author": {
        "name": "Shaohua Li",
        "email": "shaohua.li@intel.com",
        "time": "Thu Dec 03 12:58:05 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 12:58:05 2009 +0100"
      },
      "message": "cfq-iosched: no dispatch limit for single queue\n\nSince commit 2f5cb7381b737e24c8046fd4aeab571fb71315f5, each queue can send\nup to 4 * 4 requests if only one queue exists. I wonder why we have such limit.\nDevice supports tag can send more requests. For example, AHCI can send 31\nrequests. Test (direct aio randread) shows the limits reduce about 4% disk\nthoughput.\nOn the other hand, since we send one request one time, if other queue\npop when current is sending more than cfq_quantum requests, current queue will\nstop send requests soon after one request, so sounds there is no big latency.\n\nSigned-off-by: Shaohua Li \u003cshaohua.li@intel.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "98262f2762f0067375f83824d81ea929e37e6bfe",
      "tree": "a26618d5c305eed975501c80cb02bc0f1b6e4524",
      "parents": [
        "464191c65b85a8ec68a6e1a6293af625287c807e"
      ],
      "author": {
        "name": "Martin K. Petersen",
        "email": "martin.petersen@oracle.com",
        "time": "Thu Dec 03 09:24:48 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Dec 03 09:24:48 2009 +0100"
      },
      "message": "block: Allow devices to indicate whether discarded blocks are zeroed\n\nThe discard ioctl is used by mkfs utilities to clear a block device\nprior to putting metadata down.  However, not all devices return zeroed\nblocks after a discard.  Some drives return stale data, potentially\ncontaining old superblocks.  It is therefore important to know whether\ndiscarded blocks are properly zeroed.\n\nBoth ATA and SCSI drives have configuration bits that indicate whether\nzeroes are returned after a discard operation.  Implement a block level\ninterface that allows this information to be bubbled up the stack and\nqueried via a new block device ioctl.\n\nSigned-off-by: Martin K. Petersen \u003cmartin.petersen@oracle.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "464191c65b85a8ec68a6e1a6293af625287c807e",
      "tree": "4d4b91a3a4ce2faeb63758b119f0fb229fcc57ea",
      "parents": [
        "8e550632cccae34e265cb066691945515eaa7fb5"
      ],
      "author": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Mon Nov 30 09:38:13 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Mon Nov 30 09:38:13 2009 +0100"
      },
      "message": "Revert \"cfq: Make use of service count to estimate the rb_key offset\"\n\nThis reverts commit 3586e917f2c7df769d173c4ec99554cb40a911e5.\n\nCorrado Zoccolo \u003cczoccolo@gmail.com\u003e correctly points out, that we need\nconsistency of rb_key offset across groups. This means we cannot properly\nuse the per-service_tree service count. Revert this change.\n\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "8e550632cccae34e265cb066691945515eaa7fb5",
      "tree": "5aa4f97734b85076c1e743df143e63a9c12c294f",
      "parents": [
        "76280aff1c7e9ae761cac4b48591c43cd7d69159"
      ],
      "author": {
        "name": "Corrado Zoccolo",
        "email": "czoccolo@gmail.com",
        "time": "Thu Nov 26 10:02:58 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Nov 26 10:39:31 2009 +0100"
      },
      "message": "cfq-iosched: fix corner cases in idling logic\n\nIdling logic was disabled in some corner cases, leading to unfair share\n for noidle queues.\n * the idle timer was not armed if there were other requests in the\n   driver. unfortunately, those requests could come from other workloads,\n   or queues for which we don\u0027t enable idling. So we will check only\n   pending requests from the active queue\n * rq_noidle check on no-idle queue could disable the end of tree idle if\n   the last completed request was rq_noidle. Now, we will disable that\n   idle only if all the queues served in the no-idle tree had rq_noidle\n   requests.\n\nReported-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Corrado Zoccolo \u003cczoccolo@gmail.com\u003e\nAcked-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "76280aff1c7e9ae761cac4b48591c43cd7d69159",
      "tree": "f8b354746a96cf45a4d0fc980df4e37e3c37b173",
      "parents": [
        "e4a229196a7c676514c78f6783f8994f64bf681c"
      ],
      "author": {
        "name": "Corrado Zoccolo",
        "email": "czoccolo@gmail.com",
        "time": "Thu Nov 26 10:02:58 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Nov 26 10:39:31 2009 +0100"
      },
      "message": "cfq-iosched: idling on deep seeky sync queues\n\nSeeky sync queues with large depth can gain unfairly big share of disk\n time, at the expense of other seeky queues. This patch ensures that\n idling will be enabled for queues with I/O depth at least 4, and small\n think time. The decision to enable idling is sticky, until an idle\n window times out without seeing a new request.\n\nThe reasoning behind the decision is that, if an application is using\nlarge I/O depth, it is already optimized to make full utilization of\nthe hardware, and therefore we reserve a slice of exclusive use for it.\n\nReported-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Corrado Zoccolo \u003cczoccolo@gmail.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "e4a229196a7c676514c78f6783f8994f64bf681c",
      "tree": "b2a9e72f863cfaadaad697158969214cd8bb5681",
      "parents": [
        "e459dd08f45d2aa68abb0c02f8ab045cf8a598b8"
      ],
      "author": {
        "name": "Corrado Zoccolo",
        "email": "czoccolo@gmail.com",
        "time": "Thu Nov 26 10:02:58 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Nov 26 10:39:31 2009 +0100"
      },
      "message": "cfq-iosched: fix no-idle preemption logic\n\nAn incoming no-idle queue should preempt the active no-idle queue\n only if the active queue is idling due to service tree empty.\n Previous code was buggy in two ways:\n * it relied on service_tree field to be set on the active queue, while\n   it is not set when the code is idling for a new request\n * it didn\u0027t check for the service tree empty condition, so could lead to\n   LIFO behaviour if multiple queues with depth \u003e 1 were preempting each\n   other on an non-NCQ device.\n\nReported-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Corrado Zoccolo \u003cczoccolo@gmail.com\u003e\nAcked-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "e459dd08f45d2aa68abb0c02f8ab045cf8a598b8",
      "tree": "e5bba2c95dbbd93d2880fdc81e1ea7589625a6ed",
      "parents": [
        "75e7b634309ef4eabf8a93d36e58863f727fa209"
      ],
      "author": {
        "name": "Corrado Zoccolo",
        "email": "czoccolo@gmail.com",
        "time": "Thu Nov 26 10:02:57 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Nov 26 10:02:57 2009 +0100"
      },
      "message": "cfq-iosched: fix ncq detection code\n\nCFQ\u0027s detection of queueing devices initially assumes a queuing device\nand detects if the queue depth reaches a certain threshold.\nHowever, it will reconsider this choice periodically.\n\nUnfortunately, if device is considered not queuing, CFQ will force a\nunit queue depth for some workloads, thus defeating the detection logic.\nThis leads to poor performance on queuing hardware,\nsince the idle window remains enabled.\n\nGiven this premise, switching to hw_tag \u003d 0 after we have proved at\nleast once that the device is NCQ capable is not a good choice.\n\nThe new detection code starts in an indeterminate state, in which CFQ behaves\nas if hw_tag \u003d 1, and then, if for a long observation period we never saw\nlarge depth, we switch to hw_tag \u003d 0, otherwise we stick to hw_tag \u003d 1,\nwithout reconsidering it again.\n\nSigned-off-by: Corrado Zoccolo \u003cczoccolo@gmail.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "c16632bab1a17e357cec66920ceb3f0630009360",
      "tree": "6937755404314252f0bf2c46eec374c32c12f8b1",
      "parents": [
        "2d4dc890b5c8fabd818a8586607e6843c4375e62"
      ],
      "author": {
        "name": "Corrado Zoccolo",
        "email": "czoccolo@gmail.com",
        "time": "Thu Nov 26 09:41:21 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Nov 26 09:46:46 2009 +0100"
      },
      "message": "cfq-iosched: cleanup unreachable code\n\ncfq_should_idle returns false for no-idle queues that are not the last,\nso the control flow will never reach the removed code in a state that\nsatisfies the if condition.\nThe unreachable code was added to emulate previous cfq behaviour for\nnon-NCQ rotational devices. My tests show that even without it, the\nperformances and fairness are comparable with previous cfq, thanks to\nthe fact that all seeky queues are grouped together, and that we idle at\nthe end of the tree.\n\nSigned-off-by: Corrado Zoccolo \u003cczoccolo@gmail.com\u003e\nAcked-by: Vivek Goyal \u003cvgoyal@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "2d4dc890b5c8fabd818a8586607e6843c4375e62",
      "tree": "9976ed7b0eed0056f8289aeb6a2b0abf8c940454",
      "parents": [
        "3586e917f2c7df769d173c4ec99554cb40a911e5"
      ],
      "author": {
        "name": "Ilya Loginov",
        "email": "isloginov@gmail.com",
        "time": "Thu Nov 26 09:16:19 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Nov 26 09:16:19 2009 +0100"
      },
      "message": "block: add helpers to run flush_dcache_page() against a bio and a request\u0027s pages\n\nMtdblock driver doesn\u0027t call flush_dcache_page for pages in request.  So,\nthis causes problems on architectures where the icache doesn\u0027t fill from\nthe dcache or with dcache aliases.  The patch fixes this.\n\nThe ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE symbol was introduced to avoid\npointless empty cache-thrashing loops on architectures for which\nflush_dcache_page() is a no-op.  Every architecture was provided with this\nflush pages on architectires where ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE is\nequal 1 or do nothing otherwise.\n\nSee \"fix mtd_blkdevs problem with caches on some architectures\" discussion\non LKML for more information.\n\nSigned-off-by: Ilya Loginov \u003cisloginov@gmail.com\u003e\nCc: Ingo Molnar \u003cmingo@elte.hu\u003e\nCc: David Woodhouse \u003cdwmw2@infradead.org\u003e\nCc: Peter Horton \u003cphorton@bitbox.co.uk\u003e\nCc: \"Ed L. Cashin\" \u003cecashin@coraid.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "3586e917f2c7df769d173c4ec99554cb40a911e5",
      "tree": "d72ad5ca6c17a3db628734e36b22d79065e0eb49",
      "parents": [
        "32a87c0114f37871aefb12a30de3e0c3300e3646"
      ],
      "author": {
        "name": "Gui Jianfeng",
        "email": "guijianfeng@cn.fujitsu.com",
        "time": "Thu Nov 26 09:14:11 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Nov 26 09:14:11 2009 +0100"
      },
      "message": "cfq: Make use of service count to estimate the rb_key offset\n\nFor the moment, different workload cfq queues are put into different\nservice trees. But CFQ still uses \"busy_queues\" to estimate rb_key\noffset when inserting a cfq queue into a service tree. I think this\nisn\u0027t appropriate, and it should make use of service tree count to do\nthis estimation. This patch is for for-2.6.33 branch.\n\nSigned-off-by: Gui Jianfeng \u003cguijianfeng@cn.fujitsu.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "ad5ebd2fa2557b04a653bb3c3377a47da8f9b8e9",
      "tree": "f70ba006e73db3450b468c3098d43fc2a392b1da",
      "parents": [
        "86b37281411cf1e9bc0a6b5406c45edb7bd9ea5d"
      ],
      "author": {
        "name": "Randy Dunlap",
        "email": "randy.dunlap@oracle.com",
        "time": "Wed Nov 11 13:47:45 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Wed Nov 11 13:47:45 2009 +0100"
      },
      "message": "block: jiffies fixes\n\nUse HZ-independent calculation of milliseconds.\nAdd jiffies.h where it was missing since functions or macros\nfrom it are used.\n\nSigned-off-by: Randy Dunlap \u003crandy.dunlap@oracle.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "86b37281411cf1e9bc0a6b5406c45edb7bd9ea5d",
      "tree": "729db57dd52054af1bc16b4afb131093dfc9d255",
      "parents": [
        "cf7c25cf91f632a3528669fc0876e1fc8355ff9b"
      ],
      "author": {
        "name": "Martin K. Petersen",
        "email": "martin.petersen@oracle.com",
        "time": "Tue Nov 10 11:50:21 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Nov 10 11:50:21 2009 +0100"
      },
      "message": "block: Expose discard granularity\n\nWhile SSDs track block usage on a per-sector basis, RAID arrays often\nhave allocation blocks that are bigger.  Allow the discard granularity\nand alignment to be set and teach the topology stacking logic how to\nhandle them.\n\nSigned-off-by: Martin K. Petersen \u003cmartin.petersen@oracle.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "cf7c25cf91f632a3528669fc0876e1fc8355ff9b",
      "tree": "7967e65544dd49cb7333363ec928722a9e4a1562",
      "parents": [
        "622d32d3ec40d5075523656ef0ea836f6a595ae3"
      ],
      "author": {
        "name": "Corrado Zoccolo",
        "email": "czoccolo@gmail.com",
        "time": "Sun Nov 08 17:16:46 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Sun Nov 08 17:16:46 2009 +0100"
      },
      "message": "cfq-iosched: fix next_rq computation\n\nCfq has a bug in computation of next_rq, that affects transition\nbetween multiple sequential request streams in a single queue\n(e.g.: two sequential buffered writers of the same priority),\ncausing the alternation between the two streams for a transient period.\n\n  8,0    1    18737     0.260400660  5312  D   W 141653311 + 256\n  8,0    1    20839     0.273239461  5400  D   W 141653567 + 256\n  8,0    1    20841     0.276343885  5394  D   W 142803919 + 256\n  8,0    1    20843     0.279490878  5394  D   W 141668927 + 256\n  8,0    1    20845     0.292459993  5400  D   W 142804175 + 256\n  8,0    1    20847     0.295537247  5400  D   W 141668671 + 256\n  8,0    1    20849     0.298656337  5400  D   W 142804431 + 256\n  8,0    1    20851     0.311481148  5394  D   W 141668415 + 256\n  8,0    1    20853     0.314421305  5394  D   W 142804687 + 256\n  8,0    1    20855     0.318960112  5400  D   W 142804943 + 256\n\nThe fix makes sure that the next_rq is computed from the last\ndispatched request, and not affected by merging.\n\n  8,0    1    37776     4.305161306     0  D   W 141738087 + 256\n  8,0    1    37778     4.308298091     0  D   W 141738343 + 256\n  8,0    1    37780     4.312885190     0  D   W 141738599 + 256\n  8,0    1    37782     4.315933291     0  D   W 141738855 + 256\n  8,0    1    37784     4.319064459     0  D   W 141739111 + 256\n  8,0    1    37786     4.331918431  5672  D   W 142803007 + 256\n  8,0    1    37788     4.334930332  5672  D   W 142803263 + 256\n  8,0    1    37790     4.337902723  5672  D   W 142803519 + 256\n  8,0    1    37792     4.342359774  5672  D   W 142803775 + 256\n  8,0    1    37794     4.345318286     0  D   W 142804031 + 256\n\nSigned-off-by: Corrado Zoccolo \u003cczoccolo@gmail.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "476d42f138ba82389a92a894d8a630a70d36278f",
      "tree": "87ab38bd8c5ccfe5b2aa0de0f434768eb7b59cad",
      "parents": [
        "cc56f7de7f00d188c7c4da1e9861581853b9e92f"
      ],
      "author": {
        "name": "H Hartley Sweeten",
        "email": "hartleys@visionengravers.com",
        "time": "Wed Nov 04 09:10:33 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Wed Nov 04 09:10:33 2009 +0100"
      },
      "message": "block/scsi_ioctl.c: quiet sparse noise\n\nQuiet sparse noise about symbol\u0027s not being declared.\n\nSymbol blk_default_cmd_filter is only used locally and should be static.\n\nThe function blk_scsi_ioctl_init() is a fs_initcall and should also be\nstatic.\n\nSigned-off-by: H Hartley Sweeten \u003chsweeten@visionengravers.com\u003e\nCc: James Bottomley \u003cJames.Bottomley@HansenPartnership.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "e00ef7997195e4f8e10593727a6286e2e2802159",
      "tree": "51f73547c081f9068296c0c166599e5fbe340c9c",
      "parents": [
        "125c4f221a5352ae08aef2898055b879ad963f01"
      ],
      "author": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Wed Nov 04 08:54:55 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Wed Nov 04 08:54:55 2009 +0100"
      },
      "message": "cfq-iosched: get rid of the coop_preempt flag\n\nWe need to rework this logic post the cooperating cfq_queue merging,\nfor now just get rid of it and Jeff Moyer will fix the fall out.\n\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "125c4f221a5352ae08aef2898055b879ad963f01",
      "tree": "3114b880f0da09535d164923698a7e8d0b700e54",
      "parents": [
        "2058297d2d045cb57138c33b87cfabcc80e65186"
      ],
      "author": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Nov 03 21:25:45 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Nov 03 21:25:45 2009 +0100"
      },
      "message": "cfq-iosched: fix merge error\n\nWe ended up with testing the same condition twice, pretty\npointless. Remove that first if.\n\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "2058297d2d045cb57138c33b87cfabcc80e65186",
      "tree": "7ccffd0e162cbd7471f643561e79f23abb989a62",
      "parents": [
        "150e6c67f4bf6ab51e62defc41bd19a2eefe5709",
        "4b27e1bb442e964903f8a3fa6bdf33a602dc0941"
      ],
      "author": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Nov 03 21:14:39 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Nov 03 21:14:39 2009 +0100"
      },
      "message": "Merge branch \u0027for-linus\u0027 into for-2.6.33\n\nConflicts:\n\tblock/cfq-iosched.c\n\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "150e6c67f4bf6ab51e62defc41bd19a2eefe5709",
      "tree": "586bd5450afc4f142d78017389af260e76c19f0b",
      "parents": [
        "4f570f995f68ef77aae7e5a441222f59232f2d0e",
        "5869619cb5b26754574375472fe54a390edf34c7"
      ],
      "author": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Nov 03 21:12:10 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Nov 03 21:12:10 2009 +0100"
      },
      "message": "Merge branch \u0027cfq-2.6.33\u0027 into for-2.6.33\n"
    },
    {
      "commit": "4b27e1bb442e964903f8a3fa6bdf33a602dc0941",
      "tree": "d7eecb66f6a75dbff292fbd03b643b04ed075289",
      "parents": [
        "e6ec4fe24572ee265723d895ec4159e5559c8266"
      ],
      "author": {
        "name": "Shaohua Li",
        "email": "shaohua.li@intel.com",
        "time": "Tue Nov 03 20:25:02 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Nov 03 20:25:02 2009 +0100"
      },
      "message": "cfq-iosched: limit coop preemption\n\nCFQ has an optimization for cooperated applications. if several\nio-context have close requests, they will get boost. But the\noptimization get abused. Considering thread a, b, which work on one\nfile. a reads sectors s, s+2, s+4, ...; b reads sectors s+1, s+3, s\n+5, ... Both a and b are sequential read, so they can open idle window.\na reads a sector s and goes to idle window and wakeup b. b reads sector\ns+1, since in current implementation, cfq_should_preempt() thinks a and\nb are cooperators, b will preempt a. b then reads sector s+1 and goes to\nidle window and wakeup a. for the same reason, a will preempt b and\nreads s+2. a and b will continue the circle. The circle will be very\nlong, and a and b will occupy whole disk queue. Other applications will\nnearly have no chance to run.\n\nFix this limiting coop preempt until a queue is scheduled normally\nagain.\n\nSigned-off-by: Shaohua Li \u003cshaohua.li@intel.com\u003e\nAcked-by: Jeff Moyer \u003cjmoyer@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "e6ec4fe24572ee265723d895ec4159e5559c8266",
      "tree": "cf61a73b2e50d695579cffe4226d41da5c889f8f",
      "parents": [
        "8c4db3355b0fcc9ad77431f15b955efa0645b5d0"
      ],
      "author": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Nov 03 20:21:35 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Nov 03 20:21:35 2009 +0100"
      },
      "message": "cfq-iosched: fix bad return value cfq_should_preempt()\n\nCommit a6151c3a5c8e1ff5a28450bc8d6a99a2a0add0a7 inadvertently reversed\na preempt condition check, potentially causing a performance regression.\nMake the meta check correct again.\n\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "dddb74519aec2081204d203a97578c9fc4e9fb64",
      "tree": "8737fb08028c1d0bbf01775704a7dc41501bbf71",
      "parents": [
        "ab0a9735e06914ce4d2a94ffa41497dbc142fe7f"
      ],
      "author": {
        "name": "Corrado Zoccolo",
        "email": "czoccolo@gmail.com",
        "time": "Mon Nov 02 10:40:37 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Mon Nov 02 10:40:37 2009 +0100"
      },
      "message": "cfq-iosched: simplify prio-unboost code\n\nEliminate redundant checks.\n\nSigned-off-by: Corrado Zoccolo \u003cczoccolo@gmail.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "5869619cb5b26754574375472fe54a390edf34c7",
      "tree": "20e0b9852aea2a4ede1b76d0f3672233b31e2399",
      "parents": [
        "718eee0579b802aabe3bafacf09d0a9b0830f1dd"
      ],
      "author": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Wed Oct 28 09:27:07 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Wed Oct 28 09:27:07 2009 +0100"
      },
      "message": "cfq-iosched: fix style issue in cfq_get_avg_queues()\n\nLine breaks and bad brace placement.\n\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "718eee0579b802aabe3bafacf09d0a9b0830f1dd",
      "tree": "3a85a6d38ed7b68ed6ca21d04158afee13980e5e",
      "parents": [
        "a6d44e982d3734583b3b4e1d36921af8cfd61fc0"
      ],
      "author": {
        "name": "Corrado Zoccolo",
        "email": "czoccolo@gmail.com",
        "time": "Mon Oct 26 22:45:29 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Wed Oct 28 09:23:26 2009 +0100"
      },
      "message": "cfq-iosched: fairness for sync no-idle queues\n\nCurrently no-idle queues in cfq are not serviced fairly:\neven if they can only dispatch a small number of requests at a time,\nthey have to compete with idling queues to be serviced, experiencing\nlarge latencies.\n\nWe should notice, instead, that no-idle queues are the ones that would\nbenefit most from having low latency, in fact they are any of:\n* processes with large think times (e.g. interactive ones like file\n  managers)\n* seeky (e.g. programs faulting in their code at startup)\n* or marked as no-idle from upper levels, to improve latencies of those\n  requests.\n\nThis patch improves the fairness and latency for those queues, by:\n* separating sync idle, sync no-idle and async queues in separate\n  service_trees, for each priority\n* service all no-idle queues together\n* and idling when the last no-idle queue has been serviced, to\n  anticipate for more no-idle work\n* the timeslices allotted for idle and no-idle service_trees are\n  computed proportionally to the number of processes in each set.\n\nServicing all no-idle queues together should have a performance boost\nfor NCQ-capable drives, without compromising fairness.\n\nSigned-off-by: Corrado Zoccolo \u003cczoccolo@gmail.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "a6d44e982d3734583b3b4e1d36921af8cfd61fc0",
      "tree": "1d9b409057361524af2e097fe5de1c505533d603",
      "parents": [
        "c0324a020e5b351f100569b128715985f1023af8"
      ],
      "author": {
        "name": "Corrado Zoccolo",
        "email": "czoccolo@gmail.com",
        "time": "Mon Oct 26 22:45:11 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Wed Oct 28 09:23:26 2009 +0100"
      },
      "message": "cfq-iosched: enable idling for last queue on priority class\n\ncfq can disable idling for queues in various circumstances.\nWhen workloads of different priorities are competing, if the higher\npriority queue has idling disabled, lower priority queues may steal\nits disk share. For example, in a scenario with an RT process\nperforming seeky reads vs a BE process performing sequential reads,\non an NCQ enabled hardware, with low_latency unset,\nthe RT process will dispatch only the few pending requests every full\nslice of service for the BE process.\n\nThe patch solves this issue by always performing idle on the last\nqueue at a given priority class \u003e idle. If the same process, or one\nthat can pre-empt it (so at the same priority or higher), submits a\nnew request within the idle window, the lower priority queue won\u0027t\ndispatch, saving the disk bandwidth for higher priority ones.\n\nNote: this doesn\u0027t touch the non_rotational + NCQ case (no hardware\nto test if this is a benefit in that case).\n\nSigned-off-by: Corrado Zoccolo \u003cczoccolo@gmail.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "c0324a020e5b351f100569b128715985f1023af8",
      "tree": "56d99ec857349fa07dd9ddfdacfa091c7c11af44",
      "parents": [
        "aa6f6a3de18131348f70951efb2c56d806033e09"
      ],
      "author": {
        "name": "Corrado Zoccolo",
        "email": "czoccolo@gmail.com",
        "time": "Tue Oct 27 19:16:03 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Wed Oct 28 09:23:26 2009 +0100"
      },
      "message": "cfq-iosched: reimplement priorities using different service trees\n\nWe use different service trees for different priority classes.\nThis allows a simplification in the service tree insertion code, that no\nlonger has to consider priority while walking the tree.\n\nSigned-off-by: Corrado Zoccolo \u003cczoccolo@gmail.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "aa6f6a3de18131348f70951efb2c56d806033e09",
      "tree": "3565b2f9d2390d4ec054f32658461e781f106997",
      "parents": [
        "5db5d64277bf390056b1a87d0bb288c8b8553f96"
      ],
      "author": {
        "name": "Corrado Zoccolo",
        "email": "czoccolo@gmail.com",
        "time": "Mon Oct 26 22:44:33 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Wed Oct 28 09:23:26 2009 +0100"
      },
      "message": "cfq-iosched: preparation to handle multiple service trees\n\nWe embed a pointer to the service tree in each queue, to handle multiple\nservice trees easily.\nService trees are enriched with a counter.\ncfq_add_rq_rb is invoked after putting the rq in the fifo, to ensure\nthat all fields in rq are properly initialized.\n\nSigned-off-by: Corrado Zoccolo \u003cczoccolo@gmail.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "5db5d64277bf390056b1a87d0bb288c8b8553f96",
      "tree": "eced8cdeae49e6920bbb9ae18b33ed7001332233",
      "parents": [
        "1a1238a7dd48e48b3bba8f426a1d61c22c80d6d1"
      ],
      "author": {
        "name": "Corrado Zoccolo",
        "email": "czoccolo@gmail.com",
        "time": "Mon Oct 26 22:44:04 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Wed Oct 28 09:23:26 2009 +0100"
      },
      "message": "cfq-iosched: adapt slice to number of processes doing I/O\n\nWhen the number of processes performing I/O concurrently increases,\na fixed time slice per process will cause large latencies.\n\nThis patch, if low_latency mode is enabled,  will scale the time slice\nassigned to each process according to a 300ms target latency.\n\nIn order to keep fairness among processes:\n* The number of active processes is computed using a special form of\nrunning average, that quickly follows sudden increases (to keep latency low),\nand decrease slowly (to have fairness in spite of rapid decreases of this\nvalue).\n\nTo safeguard sequential bandwidth, we impose a minimum time slice\n(computed using 2*cfq_slice_idle as base, adjusted according to priority\nand async-ness).\n\nSigned-off-by: Corrado Zoccolo \u003cczoccolo@gmail.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "1a1238a7dd48e48b3bba8f426a1d61c22c80d6d1",
      "tree": "08a39610689b5da8e8d61701864b8eb257acd6d7",
      "parents": [
        "e6c5bc737ab71e4af6025ef7d150f5a26ae5f146"
      ],
      "author": {
        "name": "Shaohua Li",
        "email": "shaohua.li@intel.com",
        "time": "Tue Oct 27 08:46:23 2009 +0100"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Oct 27 08:46:23 2009 +0100"
      },
      "message": "cfq-iosched: improve hw_tag detection\n\nIf active queue hasn\u0027t enough requests and idle window opens, cfq will not\ndispatch sufficient requests to hardware. In such situation, current code\nwill zero hw_tag. But this is because cfq doesn\u0027t dispatch enough requests\ninstead of hardware queue doesn\u0027t work. Don\u0027t zero hw_tag in such case.\n\nSigned-off-by: Shaohua Li \u003cshaohua.li@intel.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "e6c5bc737ab71e4af6025ef7d150f5a26ae5f146",
      "tree": "01127225a83bdcae30b261b9f21bb89faa7db8ce",
      "parents": [
        "b3b6d0408c953524f979468562e7e210d8634150"
      ],
      "author": {
        "name": "Jeff Moyer",
        "email": "jmoyer@redhat.com",
        "time": "Fri Oct 23 17:14:52 2009 -0400"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Mon Oct 26 14:34:47 2009 +0100"
      },
      "message": "cfq: break apart merged cfqqs if they stop cooperating\n\ncfq_queues are merged if they are issuing requests within the mean seek\ndistance of one another.  This patch detects when the coopearting stops and\nbreaks the queues back up.\n\nSigned-off-by: Jeff Moyer \u003cjmoyer@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "b3b6d0408c953524f979468562e7e210d8634150",
      "tree": "1556cb393f2edc09e64c8961f6792cbb79b4e288",
      "parents": [
        "df5fe3e8e13883f58dc97489076bbcc150789a21"
      ],
      "author": {
        "name": "Jeff Moyer",
        "email": "jmoyer@redhat.com",
        "time": "Fri Oct 23 17:14:51 2009 -0400"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Mon Oct 26 14:34:47 2009 +0100"
      },
      "message": "cfq: change the meaning of the cfqq_coop flag\n\nThe flag used to indicate that a cfqq was allowed to jump ahead in the\nscheduling order due to submitting a request close to the queue that\njust executed.  Since closely cooperating queues are now merged, the flag\nholds little meaning.  Change it to indicate that multiple queues were\nmerged.  This will later be used to allow the breaking up of merged queues\nwhen they are no longer cooperating.\n\nSigned-off-by: Jeff Moyer \u003cjmoyer@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "df5fe3e8e13883f58dc97489076bbcc150789a21",
      "tree": "b05ce6760cd2b52e42dca22e3659a0255f4a4e4a",
      "parents": [
        "b2c18e1e08a5a9663094d57bb4be2f02226ee61c"
      ],
      "author": {
        "name": "Jeff Moyer",
        "email": "jmoyer@redhat.com",
        "time": "Fri Oct 23 17:14:50 2009 -0400"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Mon Oct 26 14:34:47 2009 +0100"
      },
      "message": "cfq: merge cooperating cfq_queues\n\nWhen cooperating cfq_queues are detected currently, they are allowed to\nskip ahead in the scheduling order.  It is much more efficient to\nautomatically share the cfq_queue data structure between cooperating processes.\nPerformance of the read-test2 benchmark (which is written to emulate the\ndump(8) utility) went from 12MB/s to 90MB/s on my SATA disk.  NFS servers\nwith multiple nfsd threads also saw performance increases.\n\nSigned-off-by: Jeff Moyer \u003cjmoyer@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "b2c18e1e08a5a9663094d57bb4be2f02226ee61c",
      "tree": "55c092706a0d8a9e645f245bf2ecc45c29ba5aa7",
      "parents": [
        "c30f33437c3f85ec48353a1ef811e148217a2aaf"
      ],
      "author": {
        "name": "Jeff Moyer",
        "email": "jmoyer@redhat.com",
        "time": "Fri Oct 23 17:14:49 2009 -0400"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Mon Oct 26 14:34:46 2009 +0100"
      },
      "message": "cfq: calculate the seek_mean per cfq_queue not per cfq_io_context\n\nasync cfq_queue\u0027s are already shared between processes within the same\npriority, and forthcoming patches will change the mapping of cic to sync\ncfq_queue from 1:1 to 1:N.  So, calculate the seekiness of a process\nbased on the cfq_queue instead of the cfq_io_context.\n\nSigned-off-by: Jeff Moyer \u003cjmoyer@redhat.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "6cafb12dc85a5bdc722791cc5070968413264909",
      "tree": "a7891dfc10d23a6757034a2beeb422ba11088662",
      "parents": [
        "d995053d045d777e78ba7eba71a6a0733f3aa726"
      ],
      "author": {
        "name": "Mark McLoughlin",
        "email": "markmc@redhat.com",
        "time": "Sat Oct 24 14:14:31 2009 +0200"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Sat Oct 24 14:14:31 2009 +0200"
      },
      "message": "block: silently error unsupported empty barriers too\n\nWith 2.6.32-rc5 in a KVM guest using dm and virtio_blk, we see the\nfollowing errors:\n\n  end_request: I/O error, dev vda, sector 0\n  end_request: I/O error, dev vda, sector 0\n\nThe errors go away if dm stops submitting empty barriers, by reverting:\n\n  commit 52b1fd5a27c625c78373e024bf570af3c9d44a79\n  Author: Mikulas Patocka \u003cmpatocka@redhat.com\u003e\n    dm: send empty barriers to targets in dm_flush\n\nWe should silently error all barriers, even empty barriers, on devices\nlike virtio_blk which don\u0027t support them.\n\nSee also:\n\n  https://bugzilla.redhat.com/514901\n\nSigned-off-by: Mark McLoughlin \u003cmarkmc@redhat.com\u003e\nSigned-off-by: Mike Snitzer \u003csnitzer@redhat.com\u003e\nAcked-by: Alasdair G Kergon \u003cagk@redhat.com\u003e\nAcked-by: Mikulas Patocka \u003cmpatocka@redhat.com\u003e\nCc: Rusty Russell \u003crusty@rustcorp.com.au\u003e\nCc: Neil Brown \u003cneilb@suse.de\u003e\nCc: Christoph Hellwig \u003chch@infradead.org\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "c30f33437c3f85ec48353a1ef811e148217a2aaf",
      "tree": "d5a0ca1e8d091a30fece2e9aeed285225c026049",
      "parents": [
        "132cc538cd90f60a0b5df6a512dfd4bc5fe2039a",
        "2ec24ff1d1875defa742c76c9c7d74dca06b7e1f"
      ],
      "author": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Oct 13 12:29:45 2009 +0200"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Oct 13 12:29:45 2009 +0200"
      },
      "message": "Merge branch \u0027for-linus\u0027 into for-2.6.33\n"
    },
    {
      "commit": "c7ebf0657b1f47d85aee8349ed6345d940d7232a",
      "tree": "c9425a433bf727aa01a0897856852296cce71f7b",
      "parents": [
        "961515f613f26b7958c56c5c71061a8231e02be7"
      ],
      "author": {
        "name": "Randy Dunlap",
        "email": "randy.dunlap@oracle.com",
        "time": "Mon Oct 12 08:20:47 2009 +0200"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Mon Oct 12 08:20:47 2009 +0200"
      },
      "message": "blk-settings: fix function parameter kernel-doc notation\n\nFix kernel-doc notation in blk-settings.c::blk_queue_max_discard_sectors().\n\nSigned-off-by: Randy Dunlap \u003crandy.dunlap@oracle.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "8c279598585e4992a41016bb973993ed15888cb3",
      "tree": "47da450c888cf5b63790e37e4b7640acbc3570a2",
      "parents": [
        "355b659c87432a4e76160640625c47fcf9174e8d"
      ],
      "author": {
        "name": "KOSAKI Motohiro",
        "email": "kosaki.motohiro@jp.fujitsu.com",
        "time": "Fri Oct 09 08:48:08 2009 +0200"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Fri Oct 09 08:48:08 2009 +0200"
      },
      "message": "elv_iosched_store(): fix strstrip() misuse\n\nelv_iosched_store() ignore the return value of strstrip().  It makes small\ninconsistent behavior.\n\nThis patch fixes it.\n\n \u003cbefore\u003e\n \u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\n # cd /sys/block/{blockdev}/queue\n\n case1:\n # echo \"anticipatory\" \u003e scheduler\n # cat scheduler\n noop [anticipatory] deadline cfq\n\n case2:\n # echo \"anticipatory \" \u003e scheduler\n # cat scheduler\n noop [anticipatory] deadline cfq\n\n case3:\n # echo \" anticipatory\" \u003e scheduler\n bash: echo: write error: Invalid argument\n\n \u003cafter\u003e\n \u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\u003d\n # cd /sys/block/{blockdev}/queue\n\n case1:\n # echo \"anticipatory\" \u003e scheduler\n # cat scheduler\n noop [anticipatory] deadline cfq\n\n case2:\n # echo \"anticipatory \" \u003e scheduler\n # cat scheduler\n noop [anticipatory] deadline cfq\n\n case3:\n # echo \" anticipatory\" \u003e scheduler\n noop [anticipatory] deadline cfq\n\nCc: Li Zefan \u003clizf@cn.fujitsu.com\u003e\nCc: Jens Axboe \u003cjens.axboe@oracle.com\u003e\nSigned-off-by: KOSAKI Motohiro \u003ckosaki.motohiro@jp.fujitsu.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "355b659c87432a4e76160640625c47fcf9174e8d",
      "tree": "1121f7c4ae13643a30abaf6091312f5b116a52bc",
      "parents": [
        "a6151c3a5c8e1ff5a28450bc8d6a99a2a0add0a7"
      ],
      "author": {
        "name": "Corrado Zoccolo",
        "email": "czoccolo@gmail.com",
        "time": "Thu Oct 08 08:43:32 2009 +0200"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Thu Oct 08 08:43:32 2009 +0200"
      },
      "message": "cfq-iosched: avoid probable slice overrun when idling\n\nIf the average think time is larger than the remaining time slice\nfor any given queue, don\u0027t allow it to idle. A succesful idle also\nmeans that we need to dispatch and complete a request, so if we don\u0027t\neven have time left for the idle process, we would overrun the slice\nin any case.\n\nSigned-off-by: Corrado Zoccolo \u003cczoccolo@gmail.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "a6151c3a5c8e1ff5a28450bc8d6a99a2a0add0a7",
      "tree": "47896def7d76c1f81d3c358a9aaee158a253b2b6",
      "parents": [
        "ec60e4f6749daf535329dac571293cf19c627aff"
      ],
      "author": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Wed Oct 07 20:02:57 2009 +0200"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Wed Oct 07 20:02:57 2009 +0200"
      },
      "message": "cfq-iosched: apply bool value where we return 0/1\n\nSaves 16 bytes of text, woohoo. But the more important point is\nthat it makes the code more readable when returning bool for 0/1\ncases.\n\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "ec60e4f6749daf535329dac571293cf19c627aff",
      "tree": "791e2a15281bf0a3b114af6f6c9c5b2d2b0dc982",
      "parents": [
        "b9c8946b192397394a0ccd4fcecb31bc060f79f8"
      ],
      "author": {
        "name": "Corrado Zoccolo",
        "email": "czoccolo@gmail.com",
        "time": "Wed Oct 07 19:51:54 2009 +0200"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Wed Oct 07 19:51:54 2009 +0200"
      },
      "message": "cfq-iosched: fix think time allowed for seekers\n\nCFQ enables idle only for processes that think less than the allowed\nidle time. Since idle time is lower for seeky queues, we should use the\ncorrect value in the comparison.\n\nSigned-off-by: Corrado Zoccolo \u003cczoccolo@gmail.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    },
    {
      "commit": "b9c8946b192397394a0ccd4fcecb31bc060f79f8",
      "tree": "54169a387e8e4a5f6f79e06de6fbdd0096198069",
      "parents": [
        "0b182d617eb50762b483658dd6dd9a9fbcb25758"
      ],
      "author": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Oct 06 20:53:44 2009 +0200"
      },
      "committer": {
        "name": "Jens Axboe",
        "email": "jens.axboe@oracle.com",
        "time": "Tue Oct 06 21:09:32 2009 +0200"
      },
      "message": "cfq-iosched: fix the slice residual sign\n\nWe should subtract the slice residual from the rb tree key, since\na negative residual count indicates that the cfqq overran its slice\nthe last time. Hence we want to add the overrun time, to position\nit a bit further away in the service tree.\n\nReported-by: Corrado Zoccolo \u003cczoccolo@gmail.com\u003e\nSigned-off-by: Jens Axboe \u003cjens.axboe@oracle.com\u003e\n"
    }
  ],
  "next": "0b182d617eb50762b483658dd6dd9a9fbcb25758"
}