)]}'
{
  "log": [
    {
      "commit": "29751f6991e845f7d002a6ae520bf996b38c8dcd",
      "tree": "f76c4c660ac4d204436f68851979343d2a9ba224",
      "parents": [
        "641c767389b19859a45e6de46d8e18cd935bdb60"
      ],
      "author": {
        "name": "Andy Whitcroft",
        "email": "apw@shadowen.org",
        "time": "Thu Jun 23 00:08:00 2005 -0700"
      },
      "committer": {
        "name": "Linus Torvalds",
        "email": "torvalds@ppc970.osdl.org",
        "time": "Thu Jun 23 09:45:05 2005 -0700"
      },
      "message": "[PATCH] sparsemem hotplug base\n\nMake sparse\u0027s initalization be accessible at runtime.  This allows sparse\nmappings to be created after boot in a hotplug situation.\n\nThis patch is separated from the previous one just to give an indication how\nmuch of the sparse infrastructure is *just* for hotplug memory.\n\nThe section_mem_map doesn\u0027t really store a pointer.  It stores something that\nis convenient to do some math against to get a pointer.  It isn\u0027t valid to\njust do *section_mem_map, so I don\u0027t think it should be stored as a pointer.\n\nThere are a couple of things I\u0027d like to store about a section.  First of all,\nthe fact that it is !NULL does not mean that it is present.  There could be\nsuch a combination where section_mem_map *is* NULL, but the math gets you\nproperly to a real mem_map.  So, I don\u0027t think that check is safe.\n\nSince we\u0027re storing 32-bit-aligned structures, we have a few bits in the\nbottom of the pointer to play with.  Use one bit to encode whether there\u0027s\nreally a mem_map there, and the other one to tell whether there\u0027s a valid\nsection there.  We need to distinguish between the two because sometimes\nthere\u0027s a gap between when a section is discovered to be present and when we\ncan get the mem_map for it.\n\nSigned-off-by: Dave Hansen \u003chaveblue@us.ibm.com\u003e\nSigned-off-by: Andy Whitcroft \u003capw@shadowen.org\u003e\nSigned-off-by: Jack Steiner \u003csteiner@sgi.com\u003e\nSigned-off-by: Bob Picco \u003cbob.picco@hp.com\u003e\nSigned-off-by: Andrew Morton \u003cakpm@osdl.org\u003e\nSigned-off-by: Linus Torvalds \u003ctorvalds@osdl.org\u003e\n"
    },
    {
      "commit": "d41dee369bff3b9dcb6328d4d822926c28cc2594",
      "tree": "a0405f3b7af3ebca21838a7d427bd75a067bf850",
      "parents": [
        "af705362ab6018071310c5fcd436a6b457517d5f"
      ],
      "author": {
        "name": "Andy Whitcroft",
        "email": "apw@shadowen.org",
        "time": "Thu Jun 23 00:07:54 2005 -0700"
      },
      "committer": {
        "name": "Linus Torvalds",
        "email": "torvalds@ppc970.osdl.org",
        "time": "Thu Jun 23 09:45:04 2005 -0700"
      },
      "message": "[PATCH] sparsemem memory model\n\nSparsemem abstracts the use of discontiguous mem_maps[].  This kind of\nmem_map[] is needed by discontiguous memory machines (like in the old\nCONFIG_DISCONTIGMEM case) as well as memory hotplug systems.  Sparsemem\nreplaces DISCONTIGMEM when enabled, and it is hoped that it can eventually\nbecome a complete replacement.\n\nA significant advantage over DISCONTIGMEM is that it\u0027s completely separated\nfrom CONFIG_NUMA.  When producing this patch, it became apparent in that NUMA\nand DISCONTIG are often confused.\n\nAnother advantage is that sparse doesn\u0027t require each NUMA node\u0027s ranges to be\ncontiguous.  It can handle overlapping ranges between nodes with no problems,\nwhere DISCONTIGMEM currently throws away that memory.\n\nSparsemem uses an array to provide different pfn_to_page() translations for\neach SECTION_SIZE area of physical memory.  This is what allows the mem_map[]\nto be chopped up.\n\nIn order to do quick pfn_to_page() operations, the section number of the page\nis encoded in page-\u003eflags.  Part of the sparsemem infrastructure enables\nsharing of these bits more dynamically (at compile-time) between the\npage_zone() and sparsemem operations.  However, on 32-bit architectures, the\nnumber of bits is quite limited, and may require growing the size of the\npage-\u003eflags type in certain conditions.  Several things might force this to\noccur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of\nmemory), an increase in the physical address space, or an increase in the\nnumber of used page-\u003eflags.\n\nOne thing to note is that, once sparsemem is present, the NUMA node\ninformation no longer needs to be stored in the page-\u003eflags.  It might provide\nspeed increases on certain platforms and will be stored there if there is\nroom.  But, if out of room, an alternate (theoretically slower) mechanism is\nused.\n\nThis patch introduces CONFIG_FLATMEM.  It is used in almost all cases where\nthere used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM\noften have to compile out the same areas of code.\n\nSigned-off-by: Andy Whitcroft \u003capw@shadowen.org\u003e\nSigned-off-by: Dave Hansen \u003chaveblue@us.ibm.com\u003e\nSigned-off-by: Martin Bligh \u003cmbligh@aracnet.com\u003e\nSigned-off-by: Adrian Bunk \u003cbunk@stusta.de\u003e\nSigned-off-by: Yasunori Goto \u003cy-goto@jp.fujitsu.com\u003e\nSigned-off-by: Bob Picco \u003cbob.picco@hp.com\u003e\nSigned-off-by: Andrew Morton \u003cakpm@osdl.org\u003e\nSigned-off-by: Linus Torvalds \u003ctorvalds@osdl.org\u003e\n"
    }
  ]
}