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* mm/mempolicy.c: fix mempolicy printing in numa_mapsDavid Rientjes2014-01-30
| | | | | | | | | | | | | | | | | | | | | As a result of commit 5606e3877ad8 ("mm: numa: Migrate on reference policy"), /proc/<pid>/numa_maps prints the mempolicy for any <pid> as "prefer:N" for the local node, N, of the process reading the file. This should only be printed when the mempolicy of <pid> is MPOL_PREFERRED for node N. If the process is actually only using the default mempolicy for local node allocation, make sure "default" is printed as expected. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Robert Lippert <rlippert@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: <stable@vger.kernel.org> [3.7+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/mempolicy.c: convert to pr_foo()Andrew Morton2014-01-29
| | | | | | | | A few printk(KERN_*'s have snuck in there. Cc: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: numa: initialise numa balancing after jump label initialisationMel Gorman2014-01-29
| | | | | | | | | | | | | | | | | The command line parsing takes place before jump labels are initialised which generates a warning if numa_balancing= is specified and CONFIG_JUMP_LABEL is set. On older kernels before commit c4b2c0c5f647 ("static_key: WARN on usage before jump_label_init was called") the kernel would have crashed. This patch enables automatic numa balancing later in the initialisation process if numa_balancing= is specified. Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Rik van Riel <riel@redhat.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'next' of ↵Linus Torvalds2014-01-28
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc Pull powerpc updates from Ben Herrenschmidt: "So here's my next branch for powerpc. A bit late as I was on vacation last week. It's mostly the same stuff that was in next already, I just added two patches today which are the wiring up of lockref for powerpc, which for some reason fell through the cracks last time and is trivial. The highlights are, in addition to a bunch of bug fixes: - Reworked Machine Check handling on kernels running without a hypervisor (or acting as a hypervisor). Provides hooks to handle some errors in real mode such as TLB errors, handle SLB errors, etc... - Support for retrieving memory error information from the service processor on IBM servers running without a hypervisor and routing them to the memory poison infrastructure. - _PAGE_NUMA support on server processors - 32-bit BookE relocatable kernel support - FSL e6500 hardware tablewalk support - A bunch of new/revived board support - FSL e6500 deeper idle states and altivec powerdown support You'll notice a generic mm change here, it has been acked by the relevant authorities and is a pre-req for our _PAGE_NUMA support" * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (121 commits) powerpc: Implement arch_spin_is_locked() using arch_spin_value_unlocked() powerpc: Add support for the optimised lockref implementation powerpc/powernv: Call OPAL sync before kexec'ing powerpc/eeh: Escalate error on non-existing PE powerpc/eeh: Handle multiple EEH errors powerpc: Fix transactional FP/VMX/VSX unavailable handlers powerpc: Don't corrupt transactional state when using FP/VMX in kernel powerpc: Reclaim two unused thread_info flag bits powerpc: Fix races with irq_work Move precessing of MCE queued event out from syscall exit path. pseries/cpuidle: Remove redundant call to ppc64_runlatch_off() in cpu idle routines powerpc: Make add_system_ram_resources() __init powerpc: add SATA_MV to ppc64_defconfig powerpc/powernv: Increase candidate fw image size powerpc: Add debug checks to catch invalid cpu-to-node mappings powerpc: Fix the setup of CPU-to-Node mappings during CPU online powerpc/iommu: Don't detach device without IOMMU group powerpc/eeh: Hotplug improvement powerpc/eeh: Call opal_pci_reinit() on powernv for restoring config space powerpc/eeh: Add restore_config operation ...
| * mm: Move change_prot_numa outside CONFIG_ARCH_USES_NUMA_PROT_NONEAneesh Kumar K.V2013-12-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | change_prot_numa should work even if _PAGE_NUMA != _PAGE_PROTNONE. On archs like ppc64 that don't use _PAGE_PROTNONE and also have a separate page table outside linux pagetable, we just need to make sure that when calling change_prot_numa we flush the hardware page table entry so that next page access result in a numa fault. We still need to make sure we use the numa faulting logic only when CONFIG_NUMA_BALANCING is set. This implies the migrate-on-fault (Lazy migration) via mbind will only work if CONFIG_NUMA_BALANCING is set. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Reviewed-by: Rik van Riel <riel@redhat.com> Acked-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* | mm: new_vma_page() cannot see NULL vma for hugetlb pagesMichal Hocko2014-01-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 11c731e81bb0 ("mm/mempolicy: fix !vma in new_vma_page()") has removed BUG_ON(!vma) from new_vma_page which is partially correct because page_address_in_vma will return EFAULT for non-linear mappings and at least shared shmem might be mapped this way. The patch also tried to prevent NULL ptr for hugetlb pages which is not correct AFAICS because hugetlb pages cannot be mapped as VM_NONLINEAR and other conditions in page_address_in_vma seem to be legit and catch real bugs. This patch restores BUG_ON for PageHuge to catch potential issues when the to-be-migrated page is not setup properly. Signed-off-by: Michal Hocko <mhocko@suse.cz> Reviewed-by: Bob Liu <bob.liu@oracle.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | numa: add a sysctl for numa_balancingAndi Kleen2014-01-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a working sysctl to enable/disable automatic numa memory balancing at runtime. This allows us to track down performance problems with this feature and is generally a good idea. This was possible earlier through debugfs, but only with special debugging options set. Also fix the boot message. [akpm@linux-foundation.org: s/sched_numa_balancing/sysctl_numa_balancing/] Signed-off-by: Andi Kleen <ak@linux.intel.com> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | mm/mempolicy: fix !vma in new_vma_page()Wanpeng Li2013-12-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BUG_ON(!vma) assumption is introduced by commit 0bf598d863e3 ("mbind: add BUG_ON(!vma) in new_vma_page()"), however, even if address = __vma_address(page, vma); and vma->start < address < vma->end page_address_in_vma() may still return -EFAULT because of many other conditions in it. As a result the while loop in new_vma_page() may end with vma=NULL. This patch revert the commit and also fix the potential dereference NULL pointer reported by Dan. http://marc.info/?l=linux-mm&m=137689530323257&w=2 kernel BUG at mm/mempolicy.c:1204! invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC CPU: 3 PID: 7056 Comm: trinity-child3 Not tainted 3.13.0-rc3+ #2 task: ffff8801ca5295d0 ti: ffff88005ab20000 task.ti: ffff88005ab20000 RIP: new_vma_page+0x70/0x90 RSP: 0000:ffff88005ab21db0 EFLAGS: 00010246 RAX: fffffffffffffff2 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000008040075 RSI: ffff8801c3d74600 RDI: ffffea00079a8b80 RBP: ffff88005ab21dc8 R08: 0000000000000004 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: fffffffffffffff2 R13: ffffea00079a8b80 R14: 0000000000400000 R15: 0000000000400000 FS: 00007ff49c6f4740(0000) GS:ffff880244e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff49c68f994 CR3: 000000005a205000 CR4: 00000000001407e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: ffffea00079a8b80 ffffea00079a8bc0 ffffea00079a8ba0 ffff88005ab21e50 ffffffff811adc7a 0000000000000000 ffff8801ca5295d0 0000000464e224f8 0000000000000000 0000000000000002 0000000000000000 ffff88020ce75c00 Call Trace: migrate_pages+0x12a/0x850 SYSC_mbind+0x513/0x6a0 SyS_mbind+0xe/0x10 ia32_do_call+0x13/0x13 Code: 85 c0 75 2f 4c 89 e1 48 89 da 31 f6 bf da 00 02 00 65 44 8b 04 25 08 f7 1c 00 e8 ec fd ff ff 5b 41 5c 41 5d 5d c3 0f 1f 44 00 00 <0f> 0b 66 0f 1f 44 00 00 4c 89 e6 48 89 df ba 01 00 00 00 e8 48 RIP [<ffffffff8119f200>] new_vma_page+0x70/0x90 RSP <ffff88005ab21db0> Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Reported-by: Dave Jones <davej@redhat.com> Reported-by: Sasha Levin <sasha.levin@oracle.com> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Reviewed-by: Bob Liu <bob.liu@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | mm/mempolicy: correct putback method for isolate pages if failedJoonsoo Kim2013-12-18
|/ | | | | | | | | | | | | | | | | | | | | | | queue_pages_range() isolates hugetlbfs pages and putback_lru_pages() can't handle these. We should change it to putback_movable_pages(). Naoya said that it is worth going into stable, because it can break in-use hugepage list. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Rafael Aquini <aquini@redhat.com> Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Christoph Lameter <cl@linux.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: <stable@vger.kernel.org> [3.12.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, mempolicy: silence gcc warningDavid Rientjes2013-11-21
| | | | | | | | | | | | | | | | | | Fengguang Wu reports that compiling mm/mempolicy.c results in a warning: mm/mempolicy.c: In function 'mpol_to_str': mm/mempolicy.c:2878:2: error: format not a string literal and no format arguments Kees says this is because he is using -Wformat-security. Silence the warning. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Fengguang Wu <fengguang.wu@intel.com> Suggested-by: Kees Cook <keescook@chromium.org> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, hugetlb: convert hugetlbfs to use split pmd lockKirill A. Shutemov2013-11-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Tested-by: Alex 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: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/mempolicy: use NUMA_NO_NODEJianguo Wu2013-11-12
| | | | | | | | | | Use more appropriate NUMA_NO_NODE instead of -1 Signed-off-by: Jianguo Wu <wujianguo@huawei.com> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm, mempolicy: make mpol_to_str robust and always succeedDavid Rientjes2013-11-12
| | | | | | | | | | | | | | | | | | | | | | | mpol_to_str() should not fail. Currently, it either fails because the string buffer is too small or because a string hasn't been defined for a mempolicy mode. If a new mempolicy mode is introduced and no string is defined for it, just warn and return "unknown". If the buffer is too small, just truncate the string and return, the same behavior as snprintf(). This also fixes a bug where there was no NULL-byte termination when doing *p++ = '=' and *p++ ':' and maxlen has been reached. Signed-off-by: David Rientjes <rientjes@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Chen Gang <gang.chen@asianux.com> Cc: Rik van Riel <riel@redhat.com> Cc: Dave Jones <davej@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* sched/numa: Skip some page migrations after a shared faultRik van Riel2013-10-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: Rik van Riel <riel@redhat.com> Signed-off-by: Mel 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: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1381141781-10992-62-git-send-email-mgorman@suse.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* mm: numa: Revert temporarily disabling of NUMA migrationRik van Riel2013-10-09
| | | | | | | | | | | | | | | | 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: Rik van Riel <riel@redhat.com> Signed-off-by: Mel 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: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1381141781-10992-61-git-send-email-mgorman@suse.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* mm: numa: Change page last {nid,pid} into {cpu,pid}Peter Zijlstra2013-10-09
| | | | | | | | | | | | | | | | | 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: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Rik 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: Ingo Molnar <mingo@kernel.org>
* mm: numa: Limit NUMA scanning to migrate-on-fault VMAsMel Gorman2013-10-09
| | | | | | | | | | | | | | | | | | | | | 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: Mel Gorman <mgorman@suse.de> Reported-and-tested-by: Joe Mario <jmario@redhat.com> Reviewed-by: Rik 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: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1381141781-10992-32-git-send-email-mgorman@suse.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* sched/numa: Do not migrate memory immediately after switching nodeRik van Riel2013-10-09
| | | | | | | | | | | | | | | | | | | | | | | | 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: Rik van Riel <riel@redhat.com> Signed-off-by: Mel 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: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1381141781-10992-31-git-send-email-mgorman@suse.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* sched/numa: Set preferred NUMA node based on number of private faultsMel Gorman2013-10-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: Mel Gorman <mgorman@suse.de> [ Fix complication error when !NUMA_BALANCING. ] Reviewed-by: Rik 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: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1381141781-10992-30-git-send-email-mgorman@suse.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* mbind: add BUG_ON(!vma) in new_vma_page()Naoya Horiguchi2013-09-11
| | | | | | | | | | | | | new_vma_page() is called only by page migration called from do_mbind(), where pages to be migrated are queued into a pagelist by queue_pages_range(). queue_pages_range() confirms that a queued page belongs to some vma, so !vma case is not supposed to be happen. This patch adds BUG_ON() to catch this unexpected case. Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/mempolicy: rename check_*range to queue_pages_*rangeNaoya Horiguchi2013-09-11
| | | | | | | | | | | | | | | | | | | The function check_range() (and its family) is not well-named, because it does not only checking something, but moving pages from list to list to do page migration for them. So queue_pages_*range is more desirable name. Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Rik van Riel <riel@redhat.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: mbind: add hugepage migration code to mbind()Naoya Horiguchi2013-09-11
| | | | | | | | | | | | | | | | | | | Extend do_mbind() to handle vma with VM_HUGETLB set. We will be able to migrate hugepage with mbind(2) after applying the enablement patch which comes later in this series. Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Andi Kleen <ak@linux.intel.com> Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Acked-by: Hillf Danton <dhillf@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Rik van Riel <riel@redhat.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* migrate: add hugepage migration code to migrate_pages()Naoya Horiguchi2013-09-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Extend check_range() to handle vma with VM_HUGETLB set. We will be able to migrate hugepage with migrate_pages(2) after applying the enablement patch which comes later in this series. Note that for larger hugepages (covered by pud entries, 1GB for x86_64 for example), we simply skip it now. Note that using pmd_huge/pud_huge assumes that hugepages are pointed to by pmd/pud. This is not true in some architectures implementing hugepage with other mechanisms like ia64, but it's OK because pmd_huge/pud_huge simply return 0 in such arch and page walker simply ignores such hugepages. Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Acked-by: Andi Kleen <ak@linux.intel.com> Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com> Acked-by: Hillf Danton <dhillf@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Rik van Riel <riel@redhat.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/mempolicy: return NULL if node is NUMA_NO_NODE in get_task_policyJianguo Wu2013-09-11
| | | | | | | | | | | | | | | If node == NUMA_NO_NODE, pol is NULL, we should return NULL instead of do "if (!pol->mode)" check. [akpm@linux-foundation.org: reorganise code] Signed-off-by: Jianguo Wu <wujianguo@huawei.com> Cc: Mel Gorman <mgorman@suse.de> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Rik van Riel <riel@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Hanjun Guo <guohanjun@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: mempolicy: turn vma_set_policy() into vma_dup_policy()Oleg Nesterov2013-09-11
| | | | | | | | | | | | | | | Simple cleanup. Every user of vma_set_policy() does the same work, this looks a bit annoying imho. And the new trivial helper which does mpol_dup() + vma_set_policy() to simplify the callers. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: mempolicy: fix mbind_range() && vma_adjust() interactionOleg Nesterov2013-07-31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | vma_adjust() does vma_set_policy(vma, vma_policy(next)) and this is doubly wrong: 1. This leaks vma->vm_policy if it is not NULL and not equal to next->vm_policy. This can happen if vma_merge() expands "area", not prev (case 8). 2. This sets the wrong policy if vma_merge() joins prev and area, area is the vma the caller needs to update and it still has the old policy. Revert commit 1444f92c8498 ("mm: merging memory blocks resets mempolicy") which introduced these problems. Change mbind_range() to recheck mpol_equal() after vma_merge() to fix the problem that commit tried to address. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Steven T Hampson <steven.t.hampson@intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Rik van Riel <riel@redhat.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/mempolicy.c: fix sp_node_init() argument orderingKOSAKI Motohiro2013-03-08
| | | | | | | | | | | | | | Currently, n_new is wrongly initialized. start and end parameter are inverted. Let's fix it. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Hugh Dickins <hughd@google.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Dave Jones <davej@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/mempolicy.c: fix wrong sp_node insertionHillf Danton2013-03-08
| | | | | | | | | | | | | | | n->end is accessed in sp_insert(). Thus it should be update before calling sp_insert(). This mistake may make kernel panic. Signed-off-by: Hillf Danton <dhillf@gmail.com> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Hugh Dickins <hughd@google.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Dave Jones <davej@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: use NUMA_NO_NODEDavid Rientjes2013-02-23
| | | | | | | | | | Make a sweep through mm/ and convert code that uses -1 directly to using the more appropriate NUMA_NO_NODE. Signed-off-by: David Rientjes <rientjes@google.com> Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: remove offlining arg to migrate_pagesHugh Dickins2013-02-23
| | | | | | | | | | | | | | | | | No functional change, but the only purpose of the offlining argument to migrate_pages() etc, was to ensure that __unmap_and_move() could migrate a KSM page for memory hotremove (which took ksm_thread_mutex) but not for other callers. Now all cases are safe, remove the arg. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Petr Holasek <pholasek@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Izik Eidus <izik.eidus@ravellosystems.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ksm: enable KSM page migrationHugh Dickins2013-02-23
| | | | | | | | | | | | | | | | | | | | | | | | | Migration of KSM pages is now safe: remove the PageKsm restrictions from mempolicy.c and migrate.c. But keep PageKsm out of __unmap_and_move()'s anon_vma contortions, which are irrelevant to KSM: it looks as if that code was preventing hotremove migration of KSM pages, unless they happened to be in swapcache. There is some question as to whether enforcing a NUMA mempolicy migration ought to migrate KSM pages, mapped into entirely unrelated processes; but moving page_mapcount > 1 is only permitted with MPOL_MF_MOVE_ALL anyway, and it seems reasonable to assume that you wouldn't set MADV_MERGEABLE on any area where this is a worry. Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Rik van Riel <riel@redhat.com> Cc: Petr Holasek <pholasek@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Izik Eidus <izik.eidus@ravellosystems.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: rename page struct field helpersMel Gorman2013-02-23
| | | | | | | | | | | | | | | | | The function names page_xchg_last_nid(), page_last_nid() and reset_page_last_nid() were judged to be inconsistent so rename them to a struct_field_op style pattern. As it looked jarring to have reset_page_mapcount() and page_nid_reset_last() beside each other in memmap_init_zone(), this patch also renames reset_page_mapcount() to page_mapcount_reset(). There are others like init_page_count() but as it is used throughout the arch code a rename would likely cause more conflicts than it is worth. [akpm@linux-foundation.org: fix zcache] Signed-off-by: Mel Gorman <mgorman@suse.de> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mempolicy: fix is_valid_nodemask()Lai Jiangshan2013-02-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | is_valid_nodemask() was introduced by commit 19770b32609b ("mm: filter based on a nodemask as well as a gfp_mask"). but it does not match its comments, because it does not check the zone which > policy_zone. Also in commit b377fd3982ad ("Apply memory policies to top two highest zones when highest zone is ZONE_MOVABLE"), this commits told us, if highest zone is ZONE_MOVABLE, we should also apply memory policies to it. so ZONE_MOVABLE should be valid zone for policies. is_valid_nodemask() need to be changed to match it. Fix: check all zones, even its zoneid > policy_zone. Use nodes_intersects() instead open code to check it. Reported-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: mempolicy: Convert shared_policy mutex to spinlockMel Gorman2013-01-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Tested-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mempolicy: remove arg from mpol_parse_str, mpol_to_strHugh Dickins2013-01-02
| | | | | | | | Remove the unused argument (formerly no_context) from mpol_parse_str() and from mpol_to_str(). Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* tmpfs mempolicy: fix /proc/mounts corrupting memoryHugh Dickins2013-01-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 e17f74af351c "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: Hugh Dickins <hughd@google.com> Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'balancenuma-v11' of ↵Linus Torvalds2012-12-16
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mel/linux-balancenuma Pull Automatic NUMA Balancing bare-bones from Mel Gorman: "There are three implementations for NUMA balancing, this tree (balancenuma), numacore which has been developed in tip/master and autonuma which is in aa.git. In almost all respects balancenuma is the dumbest of the three because its main impact is on the VM side with no attempt to be smart about scheduling. In the interest of getting the ball rolling, it would be desirable to see this much merged for 3.8 with the view to building scheduler smarts on top and adapting the VM where required for 3.9. The most recent set of comparisons available from different people are mel: https://lkml.org/lkml/2012/12/9/108 mingo: https://lkml.org/lkml/2012/12/7/331 tglx: https://lkml.org/lkml/2012/12/10/437 srikar: https://lkml.org/lkml/2012/12/10/397 The results are a mixed bag. In my own tests, balancenuma does reasonably well. It's dumb as rocks and does not regress against mainline. On the other hand, Ingo's tests shows that balancenuma is incapable of converging for this workloads driven by perf which is bad but is potentially explained by the lack of scheduler smarts. Thomas' results show balancenuma improves on mainline but falls far short of numacore or autonuma. Srikar's results indicate we all suffer on a large machine with imbalanced node sizes. My own testing showed that recent numacore results have improved dramatically, particularly in the last week but not universally. We've butted heads heavily on system CPU usage and high levels of migration even when it shows that overall performance is better. There are also cases where it regresses. Of interest is that for specjbb in some configurations it will regress for lower numbers of warehouses and show gains for higher numbers which is not reported by the tool by default and sometimes missed in treports. Recently I reported for numacore that the JVM was crashing with NullPointerExceptions but currently it's unclear what the source of this problem is. Initially I thought it was in how numacore batch handles PTEs but I'm no longer think this is the case. It's possible numacore is just able to trigger it due to higher rates of migration. These reports were quite late in the cycle so I/we would like to start with this tree as it contains much of the code we can agree on and has not changed significantly over the last 2-3 weeks." * tag 'balancenuma-v11' of git://git.kernel.org/pub/scm/linux/kernel/git/mel/linux-balancenuma: (50 commits) mm/rmap, migration: Make rmap_walk_anon() and try_to_unmap_anon() more scalable mm/rmap: Convert the struct anon_vma::mutex to an rwsem mm: migrate: Account a transhuge page properly when rate limiting mm: numa: Account for failed allocations and isolations as migration failures mm: numa: Add THP migration for the NUMA working set scanning fault case build fix mm: numa: Add THP migration for the NUMA working set scanning fault case. mm: sched: numa: Delay PTE scanning until a task is scheduled on a new node mm: sched: numa: Control enabling and disabling of NUMA balancing if !SCHED_DEBUG mm: sched: numa: Control enabling and disabling of NUMA balancing mm: sched: Adapt the scanning rate if a NUMA hinting fault does not migrate mm: numa: Use a two-stage filter to restrict pages being migrated for unlikely task<->node relationships mm: numa: migrate: Set last_nid on newly allocated page mm: numa: split_huge_page: Transfer last_nid on tail page mm: numa: Introduce last_nid to the page frame sched: numa: Slowly increase the scanning period as NUMA faults are handled mm: numa: Rate limit setting of pte_numa if node is saturated mm: numa: Rate limit the amount of memory that is migrated between nodes mm: numa: Structures for Migrate On Fault per NUMA migration rate limiting mm: numa: Migrate pages handled during a pmd_numa hinting fault mm: numa: Migrate on reference policy ...
| * mm: sched: numa: Control enabling and disabling of NUMA balancingMel Gorman2012-12-11
| | | | | | | | | | | | | | | | | | | | 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: Mel Gorman <mgorman@suse.de>
| * mm: numa: Use a two-stage filter to restrict pages being migrated for ↵Mel Gorman2012-12-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: Mel Gorman <mgorman@suse.de>
| * mm: numa: Migrate on reference policyMel Gorman2012-12-11
| | | | | | | | | | | | | | | | | | | | 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: Mel Gorman <mgorman@suse.de> Acked-by: Rik van Riel <riel@redhat.com>
| * mm: numa: Add pte updates, hinting and migration statsMel Gorman2012-12-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: Mel Gorman <mgorman@suse.de> Acked-by: Rik van Riel <riel@redhat.com>
| * mm: mempolicy: Hide MPOL_NOOP and MPOL_MF_LAZY from userspace for nowMel Gorman2012-12-11
| | | | | | | | | | | | | | | | | | | | 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: Mel Gorman <mgorman@suse.de>
| * mm: mempolicy: Implement change_prot_numa() in terms of change_protection()Mel Gorman2012-12-11
| | | | | | | | | | | | | | | | | | | | | | 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: Mel Gorman <mgorman@suse.de>
| * mm: mempolicy: Add MPOL_MF_LAZYLee Schermerhorn2012-12-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: Mel Gorman <mgorman@suse.de> Reviewed-by: Rik van Riel <riel@redhat.com>
| * mm: mempolicy: Check for misplaced pageLee Schermerhorn2012-12-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: Lee Schermerhorn <lee.schermerhorn@hp.com> Reviewed-by: Rik 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: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Mel Gorman <mgorman@suse.de>
| * mm: mempolicy: Add MPOL_NOOPLee Schermerhorn2012-12-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Reviewed-by: Rik van Riel <riel@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Mel Gorman <mgorman@suse.de>
| * mm: mempolicy: Make MPOL_LOCAL a real policyPeter Zijlstra2012-12-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Make MPOL_LOCAL a real and exposed policy such that applications that relied on the previous default behaviour can explicitly request it. Requested-by: Christoph Lameter <cl@linux.com> Reviewed-by: Rik 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: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Mel Gorman <mgorman@suse.de>
| * mm: migrate: Add a tracepoint for migrate_pagesMel Gorman2012-12-11
| | | | | | | | | | | | | | | | | | | | 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: Mel Gorman <mgorman@suse.de> Reviewed-by: Rik van Riel <riel@redhat.com>
* | mempolicy: use N_MEMORY instead N_HIGH_MEMORYLai Jiangshan2012-12-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | N_HIGH_MEMORY stands for the nodes that has normal or high memory. N_MEMORY stands for the nodes that has any memory. The code here need to handle with the nodes which have memory, we should use N_MEMORY instead. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Cc: Christoph Lameter <cl@linux.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Lin Feng <linfeng@cn.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | thp: change split_huge_page_pmd() interfaceKirill A. Shutemov2012-12-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pass vma instead of mm and add address parameter. In most cases we already have vma on the stack. We provides split_huge_page_pmd_mm() for few cases when we have mm, but not vma. This change is preparation to huge zero pmd splitting implementation. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: "H. Peter Anvin" <hpa@linux.intel.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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