1. 02 Oct, 2008 1 commit
    • Gerald Schaefer's avatar
      memory hotplug: missing zone->lock in test_pages_isolated() · 6c1b7f68
      Gerald Schaefer authored
      
      __test_page_isolated_in_pageblock() in mm/page_isolation.c has a comment
      saying that the caller must hold zone->lock. But the only caller of that
      function, test_pages_isolated(), does not hold zone->lock and the lock is
      also not acquired anywhere before. This patch adds the missing zone->lock
      to test_pages_isolated().
      
      We reproducibly run into BUG_ON(!PageBuddy(page)) in __offline_isolated_pages()
      during memory hotplug stress test, see trace below. This patch fixes that
      problem, it would be good if we could have it in 2.6.27.
      
      kernel BUG at /home/autobuild/BUILD/linux-2.6.26-20080909/mm/page_alloc.c:4561!
      illegal operation: 0001 [#1] PREEMPT SMP
      Modules linked in: dm_multipath sunrpc bonding qeth_l3 dm_mod qeth ccwgroup vmur
      CPU: 1 Not tainted 2.6.26-29.x.20080909-s390default #1
      Process memory_loop_all (pid: 10025, task: 2f444028, ksp: 2b10dd28)
      Krnl PSW : 040c0000 801727ea (__offline_isolated_pages+0x18e/0x1c4)
       R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:0 CC:0 PM:0
      Krnl GPRS: 00000000 7e27fc00 00000000 7e27fc00
       00000000 00000400 00014000 7e27fc01
       00606f00 7e27fc00 00013fe0 2b10dd28
       00000005 80172662 801727b2 2b10dd28
      Krnl Code: 801727de: 5810900c l %r1,12(%r9)
       801727e2: a7f4ffb3 brc 15,80172748
       801727e6: a7f40001 brc 15,801727e8
       >801727ea: a7f4ffbc brc 15,80172762
       801727ee: a7f40001 brc 15,801727f0
       801727f2: a7f4ffaf brc 15,80172750
       801727f6: 0707 bcr 0,%r7
       801727f8: 0017 unknown
      Call Trace:
      ([<0000000000172772>] __offline_isolated_pages+0x116/0x1c4)
       [<00000000001953a2>] offline_isolated_pages_cb+0x22/0x34
       [<000000000013164c>] walk_memory_resource+0xcc/0x11c
       [<000000000019520e>] offline_pages+0x36a/0x498
       [<00000000001004d6>] remove_memory+0x36/0x44
       [<000000000028fb06>] memory_block_change_state+0x112/0x150
       [<000000000028ffb8>] store_mem_state+0x90/0xe4
       [<0000000000289c00>] sysdev_store+0x34/0x40
       [<00000000001ee048>] sysfs_write_file+0xd0/0x178
       [<000000000019b1a8>] vfs_write+0x74/0x118
       [<000000000019b9ae>] sys_write+0x46/0x7c
       [<000000000011160e>] sysc_do_restart+0x12/0x16
       [<0000000077f3e8ca>] 0x77f3e8ca
      Signed-off-by: default avatarGerald Schaefer <gerald.schaefer@de.ibm.com>
      Acked-by: default avatarKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      6c1b7f68
  2. 02 Sep, 2008 1 commit
  3. 14 Nov, 2007 1 commit
  4. 16 Oct, 2007 1 commit
    • KAMEZAWA Hiroyuki's avatar
      memory unplug: page isolation · a5d76b54
      KAMEZAWA Hiroyuki authored
      
      Implement generic chunk-of-pages isolation method by using page grouping ops.
      
      This patch add MIGRATE_ISOLATE to MIGRATE_TYPES. By this
       - MIGRATE_TYPES increases.
       - bitmap for migratetype is enlarged.
      
      pages of MIGRATE_ISOLATE migratetype will not be allocated even if it is free.
      By this, you can isolated *freed* pages from users. How-to-free pages is not
      a purpose of this patch. You may use reclaim and migrate codes to free pages.
      
      If start_isolate_page_range(start,end) is called,
       - migratetype of the range turns to be MIGRATE_ISOLATE  if
         its type is MIGRATE_MOVABLE. (*) this check can be updated if other
         memory reclaiming works make progress.
       - MIGRATE_ISOLATE is not on migratetype fallback list.
       - All free pages and will-be-freed pages are isolated.
      To check all pages in the range are isolated or not,  use test_pages_isolated(),
      To cancel isolation, use undo_isolate_page_range().
      
      Changes V6 -> V7
       - removed unnecessary #ifdef
      
      There are HOLES_IN_ZONE handling codes...I'm glad if we can remove them..
      Signed-off-by: default avatarYasunori Goto <y-goto@jp.fujitsu.com>
      Signed-off-by: default avatarKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      a5d76b54