1. 15 11月, 2013 1 次提交
    • K
      mm, hugetlb: convert hugetlbfs to use split pmd lock · cb900f41
      Kirill A. Shutemov 提交于
      Hugetlb supports multiple page sizes. We use split lock only for PMD
      level, but not for PUD.
      
      [akpm@linux-foundation.org: coding-style fixes]
      Signed-off-by: NNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Tested-by: NAlex Thorlton <athorlton@sgi.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: "Eric W . Biederman" <ebiederm@xmission.com>
      Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Andrea Arcangeli <aarcange@redhat.com>
      Cc: Dave Hansen <dave.hansen@intel.com>
      Cc: Dave Jones <davej@redhat.com>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: Mel Gorman <mgorman@suse.de>
      Cc: Michael Kerrisk <mtk.manpages@gmail.com>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Robin Holt <robinmholt@gmail.com>
      Cc: Sedat Dilek <sedat.dilek@gmail.com>
      Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Hugh Dickins <hughd@google.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      cb900f41
  2. 13 11月, 2013 2 次提交
  3. 09 10月, 2013 6 次提交
    • R
      sched/numa: Skip some page migrations after a shared fault · de1c9ce6
      Rik van Riel 提交于
      Shared faults can lead to lots of unnecessary page migrations,
      slowing down the system, and causing private faults to hit the
      per-pgdat migration ratelimit.
      
      This patch adds sysctl numa_balancing_migrate_deferred, which specifies
      how many shared page migrations to skip unconditionally, after each page
      migration that is skipped because it is a shared fault.
      
      This reduces the number of page migrations back and forth in
      shared fault situations. It also gives a strong preference to
      the tasks that are already running where most of the memory is,
      and to moving the other tasks to near the memory.
      
      Testing this with a much higher scan rate than the default
      still seems to result in fewer page migrations than before.
      
      Memory seems to be somewhat better consolidated than previously,
      with multi-instance specjbb runs on a 4 node system.
      Signed-off-by: NRik van Riel <riel@redhat.com>
      Signed-off-by: NMel Gorman <mgorman@suse.de>
      Cc: Andrea Arcangeli <aarcange@redhat.com>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
      Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
      Link: http://lkml.kernel.org/r/1381141781-10992-62-git-send-email-mgorman@suse.deSigned-off-by: NIngo Molnar <mingo@kernel.org>
      de1c9ce6
    • R
      mm: numa: Revert temporarily disabling of NUMA migration · 1e3646ff
      Rik van Riel 提交于
      With the scan rate code working (at least for multi-instance specjbb),
      the large hammer that is "sched: Do not migrate memory immediately after
      switching node" can be replaced with something smarter. Revert temporarily
      migration disabling and all traces of numa_migrate_seq.
      Signed-off-by: NRik van Riel <riel@redhat.com>
      Signed-off-by: NMel Gorman <mgorman@suse.de>
      Cc: Andrea Arcangeli <aarcange@redhat.com>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
      Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
      Link: http://lkml.kernel.org/r/1381141781-10992-61-git-send-email-mgorman@suse.deSigned-off-by: NIngo Molnar <mingo@kernel.org>
      1e3646ff
    • P
      mm: numa: Change page last {nid,pid} into {cpu,pid} · 90572890
      Peter Zijlstra 提交于
      Change the per page last fault tracking to use cpu,pid instead of
      nid,pid. This will allow us to try and lookup the alternate task more
      easily. Note that even though it is the cpu that is store in the page
      flags that the mpol_misplaced decision is still based on the node.
      Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
      Signed-off-by: NMel Gorman <mgorman@suse.de>
      Reviewed-by: NRik van Riel <riel@redhat.com>
      Cc: Andrea Arcangeli <aarcange@redhat.com>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
      Link: http://lkml.kernel.org/r/1381141781-10992-43-git-send-email-mgorman@suse.de
      [ Fixed build failure on 32-bit systems. ]
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      90572890
    • M
      mm: numa: Limit NUMA scanning to migrate-on-fault VMAs · fc314724
      Mel Gorman 提交于
      There is a 90% regression observed with a large Oracle performance test
      on a 4 node system. Profiles indicated that the overhead was due to
      contention on sp_lock when looking up shared memory policies. These
      policies do not have the appropriate flags to allow them to be
      automatically balanced so trapping faults on them is pointless. This
      patch skips VMAs that do not have MPOL_F_MOF set.
      
      [riel@redhat.com: Initial patch]
      Signed-off-by: NMel Gorman <mgorman@suse.de>
      Reported-and-tested-by: NJoe Mario <jmario@redhat.com>
      Reviewed-by: NRik van Riel <riel@redhat.com>
      Cc: Andrea Arcangeli <aarcange@redhat.com>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
      Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
      Link: http://lkml.kernel.org/r/1381141781-10992-32-git-send-email-mgorman@suse.deSigned-off-by: NIngo Molnar <mingo@kernel.org>
      fc314724
    • R
      sched/numa: Do not migrate memory immediately after switching node · 6fe6b2d6
      Rik van Riel 提交于
      The load balancer can move tasks between nodes and does not take NUMA
      locality into account. With automatic NUMA balancing this may result in the
      tasks working set being migrated to the new node. However, as the fault
      buffer will still store faults from the old node the schduler may decide to
      reset the preferred node and migrate the task back resulting in more
      migrations.
      
      The ideal would be that the scheduler did not migrate tasks with a heavy
      memory footprint but this may result nodes being overloaded. We could
      also discard the fault information on task migration but this would still
      cause all the tasks working set to be migrated. This patch simply avoids
      migrating the memory for a short time after a task is migrated.
      Signed-off-by: NRik van Riel <riel@redhat.com>
      Signed-off-by: NMel Gorman <mgorman@suse.de>
      Cc: Andrea Arcangeli <aarcange@redhat.com>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
      Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
      Link: http://lkml.kernel.org/r/1381141781-10992-31-git-send-email-mgorman@suse.deSigned-off-by: NIngo Molnar <mingo@kernel.org>
      6fe6b2d6
    • M
      sched/numa: Set preferred NUMA node based on number of private faults · b795854b
      Mel Gorman 提交于
      Ideally it would be possible to distinguish between NUMA hinting faults that
      are private to a task and those that are shared. If treated identically
      there is a risk that shared pages bounce between nodes depending on
      the order they are referenced by tasks. Ultimately what is desirable is
      that task private pages remain local to the task while shared pages are
      interleaved between sharing tasks running on different nodes to give good
      average performance. This is further complicated by THP as even
      applications that partition their data may not be partitioning on a huge
      page boundary.
      
      To start with, this patch assumes that multi-threaded or multi-process
      applications partition their data and that in general the private accesses
      are more important for cpu->memory locality in the general case. Also,
      no new infrastructure is required to treat private pages properly but
      interleaving for shared pages requires additional infrastructure.
      
      To detect private accesses the pid of the last accessing task is required
      but the storage requirements are a high. This patch borrows heavily from
      Ingo Molnar's patch "numa, mm, sched: Implement last-CPU+PID hash tracking"
      to encode some bits from the last accessing task in the page flags as
      well as the node information. Collisions will occur but it is better than
      just depending on the node information. Node information is then used to
      determine if a page needs to migrate. The PID information is used to detect
      private/shared accesses. The preferred NUMA node is selected based on where
      the maximum number of approximately private faults were measured. Shared
      faults are not taken into consideration for a few reasons.
      
      First, if there are many tasks sharing the page then they'll all move
      towards the same node. The node will be compute overloaded and then
      scheduled away later only to bounce back again. Alternatively the shared
      tasks would just bounce around nodes because the fault information is
      effectively noise. Either way accounting for shared faults the same as
      private faults can result in lower performance overall.
      
      The second reason is based on a hypothetical workload that has a small
      number of very important, heavily accessed private pages but a large shared
      array. The shared array would dominate the number of faults and be selected
      as a preferred node even though it's the wrong decision.
      
      The third reason is that multiple threads in a process will race each
      other to fault the shared page making the fault information unreliable.
      Signed-off-by: NMel Gorman <mgorman@suse.de>
      [ Fix complication error when !NUMA_BALANCING. ]
      Reviewed-by: NRik van Riel <riel@redhat.com>
      Cc: Andrea Arcangeli <aarcange@redhat.com>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
      Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
      Link: http://lkml.kernel.org/r/1381141781-10992-30-git-send-email-mgorman@suse.deSigned-off-by: NIngo Molnar <mingo@kernel.org>
      b795854b
  4. 12 9月, 2013 6 次提交
  5. 01 8月, 2013 1 次提交
  6. 09 3月, 2013 2 次提交
  7. 24 2月, 2013 5 次提交
  8. 03 1月, 2013 3 次提交
    • M
      mm: mempolicy: Convert shared_policy mutex to spinlock · 42288fe3
      Mel Gorman 提交于
      Sasha was fuzzing with trinity and reported the following problem:
      
        BUG: sleeping function called from invalid context at kernel/mutex.c:269
        in_atomic(): 1, irqs_disabled(): 0, pid: 6361, name: trinity-main
        2 locks held by trinity-main/6361:
         #0:  (&mm->mmap_sem){++++++}, at: [<ffffffff810aa314>] __do_page_fault+0x1e4/0x4f0
         #1:  (&(&mm->page_table_lock)->rlock){+.+...}, at: [<ffffffff8122f017>] handle_pte_fault+0x3f7/0x6a0
        Pid: 6361, comm: trinity-main Tainted: G        W
        3.7.0-rc2-next-20121024-sasha-00001-gd95ef01-dirty #74
        Call Trace:
          __might_sleep+0x1c3/0x1e0
          mutex_lock_nested+0x29/0x50
          mpol_shared_policy_lookup+0x2e/0x90
          shmem_get_policy+0x2e/0x30
          get_vma_policy+0x5a/0xa0
          mpol_misplaced+0x41/0x1d0
          handle_pte_fault+0x465/0x6a0
      
      This was triggered by a different version of automatic NUMA balancing
      but in theory the current version is vunerable to the same problem.
      
      do_numa_page
        -> numa_migrate_prep
          -> mpol_misplaced
            -> get_vma_policy
              -> shmem_get_policy
      
      It's very unlikely this will happen as shared pages are not marked
      pte_numa -- see the page_mapcount() check in change_pte_range() -- but
      it is possible.
      
      To address this, this patch restores sp->lock as originally implemented
      by Kosaki Motohiro.  In the path where get_vma_policy() is called, it
      should not be calling sp_alloc() so it is not necessary to treat the PTL
      specially.
      Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
      Tested-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
      Signed-off-by: NMel Gorman <mgorman@suse.de>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      42288fe3
    • H
      mempolicy: remove arg from mpol_parse_str, mpol_to_str · a7a88b23
      Hugh Dickins 提交于
      Remove the unused argument (formerly no_context) from mpol_parse_str()
      and from mpol_to_str().
      Signed-off-by: NHugh Dickins <hughd@google.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      a7a88b23
    • H
      tmpfs mempolicy: fix /proc/mounts corrupting memory · f2a07f40
      Hugh Dickins 提交于
      Recently I suggested using "mount -o remount,mpol=local /tmp" in NUMA
      mempolicy testing.  Very nasty.  Reading /proc/mounts, /proc/pid/mounts
      or /proc/pid/mountinfo may then corrupt one bit of kernel memory, often
      in a page table (causing "Bad swap" or "Bad page map" warning or "Bad
      pagetable" oops), sometimes in a vm_area_struct or rbnode or somewhere
      worse.  "mpol=prefer" and "mpol=prefer:Node" are equally toxic.
      
      Recent NUMA enhancements are not to blame: this dates back to 2.6.35,
      when commit e17f74af "mempolicy: don't call mpol_set_nodemask() when
      no_context" skipped mpol_parse_str()'s call to mpol_set_nodemask(),
      which used to initialize v.preferred_node, or set MPOL_F_LOCAL in flags.
      With slab poisoning, you can then rely on mpol_to_str() to set the bit
      for node 0x6b6b, probably in the next page above the caller's stack.
      
      mpol_parse_str() is only called from shmem_parse_options(): no_context
      is always true, so call it unused for now, and remove !no_context code.
      Set v.nodes or v.preferred_node or MPOL_F_LOCAL as mpol_to_str() might
      expect.  Then mpol_to_str() can ignore its no_context argument also,
      the mpol being appropriately initialized whether contextualized or not.
      Rename its no_context unused too, and let subsequent patch remove them
      (that's not needed for stable backporting, which would involve rejects).
      
      I don't understand why MPOL_LOCAL is described as a pseudo-policy:
      it's a reasonable policy which suffers from a confusing implementation
      in terms of MPOL_PREFERRED with MPOL_F_LOCAL.  I believe this would be
      much more robust if MPOL_LOCAL were recognized in switch statements
      throughout, MPOL_F_LOCAL deleted, and MPOL_PREFERRED use the (possibly
      empty) nodes mask like everyone else, instead of its preferred_node
      variant (I presume an optimization from the days before MPOL_LOCAL).
      But that would take me too long to get right and fully tested.
      Signed-off-by: NHugh Dickins <hughd@google.com>
      Cc: stable@vger.kernel.org
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      f2a07f40
  9. 13 12月, 2012 2 次提交
  10. 12 12月, 2012 1 次提交
  11. 11 12月, 2012 11 次提交
    • M
      mm: sched: numa: Control enabling and disabling of NUMA balancing · 1a687c2e
      Mel Gorman 提交于
      This patch adds Kconfig options and kernel parameters to allow the
      enabling and disabling of automatic NUMA balancing. The existance
      of such a switch was and is very important when debugging problems
      related to transparent hugepages and we should have the same for
      automatic NUMA placement.
      Signed-off-by: NMel Gorman <mgorman@suse.de>
      1a687c2e
    • M
      mm: numa: Use a two-stage filter to restrict pages being migrated for unlikely... · e42c8ff2
      Mel Gorman 提交于
      mm: numa: Use a two-stage filter to restrict pages being migrated for unlikely task<->node relationships
      
      Note: This two-stage filter was taken directly from the sched/numa patch
      	"sched, numa, mm: Add the scanning page fault machinery" but is
      	only a partial extraction. As the end result is not necessarily
      	recognisable, the signed-offs-by had to be removed. Will be added
      	back if requested.
      
      While it is desirable that all threads in a process run on its home
      node, this is not always possible or necessary. There may be more
      threads than exist within the node or the node might over-subscribed
      with unrelated processes.
      
      This can cause a situation whereby a page gets migrated off its home
      node because the threads clearing pte_numa were running off-node. This
      patch uses page->last_nid to build a two-stage filter before pages get
      migrated to avoid problems with short or unlikely task<->node
      relationships.
      Signed-off-by: NMel Gorman <mgorman@suse.de>
      e42c8ff2
    • M
      mm: numa: Migrate on reference policy · 5606e387
      Mel Gorman 提交于
      This is the simplest possible policy that still does something of note.
      When a pte_numa is faulted, it is moved immediately. Any replacement
      policy must at least do better than this and in all likelihood this
      policy regresses normal workloads.
      Signed-off-by: NMel Gorman <mgorman@suse.de>
      Acked-by: NRik van Riel <riel@redhat.com>
      5606e387
    • M
      mm: numa: Add pte updates, hinting and migration stats · 03c5a6e1
      Mel Gorman 提交于
      It is tricky to quantify the basic cost of automatic NUMA placement in a
      meaningful manner. This patch adds some vmstats that can be used as part
      of a basic costing model.
      
      u    = basic unit = sizeof(void *)
      Ca   = cost of struct page access = sizeof(struct page) / u
      Cpte = Cost PTE access = Ca
      Cupdate = Cost PTE update = (2 * Cpte) + (2 * Wlock)
      	where Cpte is incurred twice for a read and a write and Wlock
      	is a constant representing the cost of taking or releasing a
      	lock
      Cnumahint = Cost of a minor page fault = some high constant e.g. 1000
      Cpagerw = Cost to read or write a full page = Ca + PAGE_SIZE/u
      Ci = Cost of page isolation = Ca + Wi
      	where Wi is a constant that should reflect the approximate cost
      	of the locking operation
      Cpagecopy = Cpagerw + (Cpagerw * Wnuma) + Ci + (Ci * Wnuma)
      	where Wnuma is the approximate NUMA factor. 1 is local. 1.2
      	would imply that remote accesses are 20% more expensive
      
      Balancing cost = Cpte * numa_pte_updates +
      		Cnumahint * numa_hint_faults +
      		Ci * numa_pages_migrated +
      		Cpagecopy * numa_pages_migrated
      
      Note that numa_pages_migrated is used as a measure of how many pages
      were isolated even though it would miss pages that failed to migrate. A
      vmstat counter could have been added for it but the isolation cost is
      pretty marginal in comparison to the overall cost so it seemed overkill.
      
      The ideal way to measure automatic placement benefit would be to count
      the number of remote accesses versus local accesses and do something like
      
      	benefit = (remote_accesses_before - remove_access_after) * Wnuma
      
      but the information is not readily available. As a workload converges, the
      expection would be that the number of remote numa hints would reduce to 0.
      
      	convergence = numa_hint_faults_local / numa_hint_faults
      		where this is measured for the last N number of
      		numa hints recorded. When the workload is fully
      		converged the value is 1.
      
      This can measure if the placement policy is converging and how fast it is
      doing it.
      Signed-off-by: NMel Gorman <mgorman@suse.de>
      Acked-by: NRik van Riel <riel@redhat.com>
      03c5a6e1
    • M
      mm: mempolicy: Hide MPOL_NOOP and MPOL_MF_LAZY from userspace for now · a720094d
      Mel Gorman 提交于
      The use of MPOL_NOOP and MPOL_MF_LAZY to allow an application to
      explicitly request lazy migration is a good idea but the actual
      API has not been well reviewed and once released we have to support it.
      For now this patch prevents an application using the services. This
      will need to be revisited.
      Signed-off-by: NMel Gorman <mgorman@suse.de>
      a720094d
    • M
      mm: mempolicy: Implement change_prot_numa() in terms of change_protection() · 4b10e7d5
      Mel Gorman 提交于
      This patch converts change_prot_numa() to use change_protection(). As
      pte_numa and friends check the PTE bits directly it is necessary for
      change_protection() to use pmd_mknuma(). Hence the required
      modifications to change_protection() are a little clumsy but the
      end result is that most of the numa page table helpers are just one or
      two instructions.
      Signed-off-by: NMel Gorman <mgorman@suse.de>
      4b10e7d5
    • L
      mm: mempolicy: Add MPOL_MF_LAZY · b24f53a0
      Lee Schermerhorn 提交于
      NOTE: Once again there is a lot of patch stealing and the end result
      	is sufficiently different that I had to drop the signed-offs.
      	Will re-add if the original authors are ok with that.
      
      This patch adds another mbind() flag to request "lazy migration".  The
      flag, MPOL_MF_LAZY, modifies MPOL_MF_MOVE* such that the selected
      pages are marked PROT_NONE. The pages will be migrated in the fault
      path on "first touch", if the policy dictates at that time.
      
      "Lazy Migration" will allow testing of migrate-on-fault via mbind().
      Also allows applications to specify that only subsequently touched
      pages be migrated to obey new policy, instead of all pages in range.
      This can be useful for multi-threaded applications working on a
      large shared data area that is initialized by an initial thread
      resulting in all pages on one [or a few, if overflowed] nodes.
      After PROT_NONE, the pages in regions assigned to the worker threads
      will be automatically migrated local to the threads on 1st touch.
      Signed-off-by: NMel Gorman <mgorman@suse.de>
      Reviewed-by: NRik van Riel <riel@redhat.com>
      b24f53a0
    • L
      mm: mempolicy: Check for misplaced page · 771fb4d8
      Lee Schermerhorn 提交于
      This patch provides a new function to test whether a page resides
      on a node that is appropriate for the mempolicy for the vma and
      address where the page is supposed to be mapped.  This involves
      looking up the node where the page belongs.  So, the function
      returns that node so that it may be used to allocated the page
      without consulting the policy again.
      
      A subsequent patch will call this function from the fault path.
      Because of this, I don't want to go ahead and allocate the page, e.g.,
      via alloc_page_vma() only to have to free it if it has the correct
      policy.  So, I just mimic the alloc_page_vma() node computation
      logic--sort of.
      
      Note:  we could use this function to implement a MPOL_MF_STRICT
      behavior when migrating pages to match mbind() mempolicy--e.g.,
      to ensure that pages in an interleaved range are reinterleaved
      rather than left where they are when they reside on any page in
      the interleave nodemask.
      Signed-off-by: NLee Schermerhorn <lee.schermerhorn@hp.com>
      Reviewed-by: NRik van Riel <riel@redhat.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      [ Added MPOL_F_LAZY to trigger migrate-on-fault;
        simplified code now that we don't have to bother
        with special crap for interleaved ]
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      Signed-off-by: NMel Gorman <mgorman@suse.de>
      771fb4d8
    • L
      mm: mempolicy: Add MPOL_NOOP · d3a71033
      Lee Schermerhorn 提交于
      This patch augments the MPOL_MF_LAZY feature by adding a "NOOP" policy
      to mbind().  When the NOOP policy is used with the 'MOVE and 'LAZY
      flags, mbind() will map the pages PROT_NONE so that they will be
      migrated on the next touch.
      
      This allows an application to prepare for a new phase of operation
      where different regions of shared storage will be assigned to
      worker threads, w/o changing policy.  Note that we could just use
      "default" policy in this case.  However, this also allows an
      application to request that pages be migrated, only if necessary,
      to follow any arbitrary policy that might currently apply to a
      range of pages, without knowing the policy, or without specifying
      multiple mbind()s for ranges with different policies.
      
      [ Bug in early version of mpol_parse_str() reported by Fengguang Wu. ]
      Bug-Reported-by: NReported-by: Fengguang Wu <fengguang.wu@intel.com>
      Signed-off-by: NLee Schermerhorn <lee.schermerhorn@hp.com>
      Reviewed-by: NRik van Riel <riel@redhat.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      Signed-off-by: NMel Gorman <mgorman@suse.de>
      d3a71033
    • P
      mm: mempolicy: Make MPOL_LOCAL a real policy · 479e2802
      Peter Zijlstra 提交于
      Make MPOL_LOCAL a real and exposed policy such that applications that
      relied on the previous default behaviour can explicitly request it.
      Requested-by: NChristoph Lameter <cl@linux.com>
      Reviewed-by: NRik van Riel <riel@redhat.com>
      Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      Signed-off-by: NMel Gorman <mgorman@suse.de>
      479e2802
    • M
      mm: migrate: Add a tracepoint for migrate_pages · 7b2a2d4a
      Mel Gorman 提交于
      The pgmigrate_success and pgmigrate_fail vmstat counters tells the user
      about migration activity but not the type or the reason. This patch adds
      a tracepoint to identify the type of page migration and why the page is
      being migrated.
      Signed-off-by: NMel Gorman <mgorman@suse.de>
      Reviewed-by: NRik van Riel <riel@redhat.com>
      7b2a2d4a