)]}'
{
  "log": [
    {
      "commit": "8d06afab73a75f40ae2864e6c296356bab1ab473",
      "tree": "1d9c8c24a1024a12a4e8df841fba5809fa914356",
      "parents": [
        "7c352bdf048811b8128019ffc1e886161e09c11c"
      ],
      "author": {
        "name": "Ingo Molnar",
        "email": "mingo@elte.hu",
        "time": "Fri Sep 09 13:10:40 2005 -0700"
      },
      "committer": {
        "name": "Linus Torvalds",
        "email": "torvalds@g5.osdl.org",
        "time": "Fri Sep 09 14:03:48 2005 -0700"
      },
      "message": "[PATCH] timer initialization cleanup: DEFINE_TIMER\n\nClean up timer initialization by introducing DEFINE_TIMER a\u0027la\nDEFINE_SPINLOCK.  Build and boot-tested on x86.  A similar patch has been\nbeen in the -RT tree for some time.\n\nSigned-off-by: Ingo Molnar \u003cmingo@elte.hu\u003e\nSigned-off-by: Andrew Morton \u003cakpm@osdl.org\u003e\nSigned-off-by: Linus Torvalds \u003ctorvalds@osdl.org\u003e\n"
    },
    {
      "commit": "fd450b7318b75343fd76b3d95416853e34e72c95",
      "tree": "e747348f7d3c9f1615963dde4f2c8baaf842415f",
      "parents": [
        "55c888d6d09a0df236adfaf8ccf06ff5d0646775"
      ],
      "author": {
        "name": "Oleg Nesterov",
        "email": "oleg@tv-sign.ru",
        "time": "Thu Jun 23 00:08:59 2005 -0700"
      },
      "committer": {
        "name": "Linus Torvalds",
        "email": "torvalds@ppc970.osdl.org",
        "time": "Thu Jun 23 09:45:16 2005 -0700"
      },
      "message": "[PATCH] timers: introduce try_to_del_timer_sync()\n\nThis patch splits del_timer_sync() into 2 functions.  The new one,\ntry_to_del_timer_sync(), returns -1 when it hits executing timer.\n\nIt can be used in interrupt context, or when the caller hold locks which\ncan prevent completion of the timer\u0027s handler.\n\nNOTE.  Currently it can\u0027t be used in interrupt context in UP case, because\n-\u003erunning_timer is used only with CONFIG_SMP.\n\nShould the need arise, it is possible to kill #ifdef CONFIG_SMP in\nset_running_timer(), it is cheap.\n\nSigned-off-by: Oleg Nesterov \u003coleg@tv-sign.ru\u003e\nSigned-off-by: Andrew Morton \u003cakpm@osdl.org\u003e\nSigned-off-by: Linus Torvalds \u003ctorvalds@osdl.org\u003e\n"
    },
    {
      "commit": "55c888d6d09a0df236adfaf8ccf06ff5d0646775",
      "tree": "deb9434abe3cf7c9b714ccb267ef5d943a847dfe",
      "parents": [
        "bdd646a44672115c986593956aa4ef105485a184"
      ],
      "author": {
        "name": "Oleg Nesterov",
        "email": "oleg@tv-sign.ru",
        "time": "Thu Jun 23 00:08:56 2005 -0700"
      },
      "committer": {
        "name": "Linus Torvalds",
        "email": "torvalds@ppc970.osdl.org",
        "time": "Thu Jun 23 09:45:16 2005 -0700"
      },
      "message": "[PATCH] timers fixes/improvements\n\nThis patch tries to solve following problems:\n\n1. del_timer_sync() is racy. The timer can be fired again after\n   del_timer_sync have checked all cpus and before it will recheck\n   timer_pending().\n\n2. It has scalability problems. All cpus are scanned to determine\n   if the timer is running on that cpu.\n\n   With this patch del_timer_sync is O(1) and no slower than plain\n   del_timer(pending_timer), unless it has to actually wait for\n   completion of the currently running timer.\n\n   The only restriction is that the recurring timer should not use\n   add_timer_on().\n\n3. The timers are not serialized wrt to itself.\n\n   If CPU_0 does mod_timer(jiffies+1) while the timer is currently\n   running on CPU 1, it is quite possible that local interrupt on\n   CPU_0 will start that timer before it finished on CPU_1.\n\n4. The timers locking is suboptimal. __mod_timer() takes 3 locks\n   at once and still requires wmb() in del_timer/run_timers.\n\n   The new implementation takes 2 locks sequentially and does not\n   need memory barriers.\n\nCurrently -\u003ebase !\u003d NULL means that the timer is pending. In that case\n-\u003ebase.lock is used to lock the timer. __mod_timer also takes timer-\u003elock\nbecause -\u003ebase can be \u003d\u003d NULL.\n\nThis patch uses timer-\u003eentry.next !\u003d NULL as indication that the timer is\npending. So it does __list_del(), entry-\u003enext \u003d NULL instead of list_del()\nwhen the timer is deleted.\n\nThe -\u003ebase field is used for hashed locking only, it is initialized\nin init_timer() which sets -\u003ebase \u003d per_cpu(tvec_bases). When the\ntvec_bases.lock is locked, it means that all timers which are tied\nto this base via timer-\u003ebase are locked, and the base itself is locked\ntoo.\n\nSo __run_timers/migrate_timers can safely modify all timers which could\nbe found on -\u003etvX lists (pending timers).\n\nWhen the timer\u0027s base is locked, and the timer removed from -\u003eentry list\n(which means that _run_timers/migrate_timers can\u0027t see this timer), it is\npossible to set timer-\u003ebase \u003d NULL and drop the lock: the timer remains\nlocked.\n\nThis patch adds lock_timer_base() helper, which waits for -\u003ebase !\u003d NULL,\nlocks the -\u003ebase, and checks it is still the same.\n\n__mod_timer() schedules the timer on the local CPU and changes it\u0027s base.\nHowever, it does not lock both old and new bases at once. It locks the\ntimer via lock_timer_base(), deletes the timer, sets -\u003ebase \u003d NULL, and\nunlocks old base. Then __mod_timer() locks new_base, sets -\u003ebase \u003d new_base,\nand adds this timer. This simplifies the code, because AB-BA deadlock is not\npossible. __mod_timer() also ensures that the timer\u0027s base is not changed\nwhile the timer\u0027s handler is running on the old base.\n\n__run_timers(), del_timer() do not change -\u003ebase anymore, they only clear\npending flag.\n\nSo del_timer_sync() can test timer-\u003ebase-\u003erunning_timer \u003d\u003d timer to detect\nwhether it is running or not.\n\nWe don\u0027t need timer_list-\u003elock anymore, this patch kills it.\n\nWe also don\u0027t need barriers. del_timer() and __run_timers() used smp_wmb()\nbefore clearing timer\u0027s pending flag. It was needed because __mod_timer()\ndid not lock old_base if the timer is not pending, so __mod_timer()-\u003elist_add()\ncould race with del_timer()-\u003elist_del(). With this patch these functions are\nserialized through base-\u003elock.\n\nOne problem. TIMER_INITIALIZER can\u0027t use per_cpu(tvec_bases). So this patch\nadds global\n\n        struct timer_base_s {\n                spinlock_t lock;\n                struct timer_list *running_timer;\n        } __init_timer_base;\n\nwhich is used by TIMER_INITIALIZER. The corresponding fields in tvec_t_base_s\nstruct are replaced by struct timer_base_s t_base.\n\nIt is indeed ugly. But this can\u0027t have scalability problems. The global\n__init_timer_base.lock is used only when __mod_timer() is called for the first\ntime AND the timer was compile time initialized. After that the timer migrates\nto the local CPU.\n\nSigned-off-by: Oleg Nesterov \u003coleg@tv-sign.ru\u003e\nAcked-by: Ingo Molnar \u003cmingo@elte.hu\u003e\nSigned-off-by: Renaud Lienhart \u003crenaud.lienhart@free.fr\u003e\nSigned-off-by: Andrew Morton \u003cakpm@osdl.org\u003e\nSigned-off-by: Linus Torvalds \u003ctorvalds@osdl.org\u003e\n"
    },
    {
      "commit": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
      "tree": "0bba044c4ce775e45a88a51686b5d9f90697ea9d",
      "parents": [],
      "author": {
        "name": "Linus Torvalds",
        "email": "torvalds@ppc970.osdl.org",
        "time": "Sat Apr 16 15:20:36 2005 -0700"
      },
      "committer": {
        "name": "Linus Torvalds",
        "email": "torvalds@ppc970.osdl.org",
        "time": "Sat Apr 16 15:20:36 2005 -0700"
      },
      "message": "Linux-2.6.12-rc2\n\nInitial git repository build. I\u0027m not bothering with the full history,\neven though we have it. We can create a separate \"historical\" git\narchive of that later if we want to, and in the meantime it\u0027s about\n3.2GB when imported into git - space that would just make the early\ngit days unnecessarily complicated, when we don\u0027t have a lot of good\ninfrastructure for it.\n\nLet it rip!\n"
    }
  ]
}