The patch titled oom: avoid oom killer for lowmem allocations has been removed from the -mm tree. Its filename was oom-avoid-oom-killer-for-lowmem-allocations.patch This patch was dropped because an updated version will be merged The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: oom: avoid oom killer for lowmem allocations From: David Rientjes <rientjes@xxxxxxxxxx> If memory has been depleted in lowmem zones even with the protection afforded to it by /proc/sys/vm/lowmem_reserve_ratio, it is unlikely that killing current users will help. The memory is either reclaimable (or migratable) already, in which case we should not invoke the oom killer at all, or it is pinned by an application for I/O. Killing such an application may leave the hardware in an unspecified state and there is no guarantee that it will be able to make a timely exit. Lowmem allocations are now failed in oom conditions when __GFP_NOFAIL is not used so that the task can perhaps recover or try again later. Previously, the heuristic provided some protection for those tasks with CAP_SYS_RAWIO, but this is no longer necessary since we will not be killing tasks for the purposes of ISA allocations. high_zoneidx is gfp_zone(gfp_flags), meaning that ZONE_NORMAL will be the default for all allocations that are not __GFP_DMA, __GFP_DMA32, __GFP_HIGHMEM, and __GFP_MOVABLE on kernels configured to support those flags. Testing for high_zoneidx being less than ZONE_NORMAL will only return true for allocations that have either __GFP_DMA or __GFP_DMA32. Signed-off-by: David Rientjes <rientjes@xxxxxxxxxx> Cc: Rik van Riel <riel@xxxxxxxxxx> Cc: Nick Piggin <npiggin@xxxxxxx> Cc: Balbir Singh <balbir@xxxxxxxxxxxxxxxxxx> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> Cc: Minchan Kim <minchan.kim@xxxxxxxxx> Cc: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/page_alloc.c | 29 ++++++++++++++++++++--------- 1 file changed, 20 insertions(+), 9 deletions(-) diff -puN mm/page_alloc.c~oom-avoid-oom-killer-for-lowmem-allocations mm/page_alloc.c --- a/mm/page_alloc.c~oom-avoid-oom-killer-for-lowmem-allocations +++ a/mm/page_alloc.c @@ -1695,6 +1695,9 @@ __alloc_pages_may_oom(gfp_t gfp_mask, un /* The OOM killer will not help higher order allocs */ if (order > PAGE_ALLOC_COSTLY_ORDER) goto out; + /* The OOM killer does not needlessly kill tasks for lowmem */ + if (high_zoneidx < ZONE_NORMAL) + goto out; /* * GFP_THISNODE contains __GFP_NORETRY and we never hit this. * Sanity check for bare calls of __GFP_THISNODE, not real OOM. @@ -1923,15 +1926,23 @@ rebalance: if (page) goto got_pg; - /* - * The OOM killer does not trigger for high-order - * ~__GFP_NOFAIL allocations so if no progress is being - * made, there are no other options and retrying is - * unlikely to help. - */ - if (order > PAGE_ALLOC_COSTLY_ORDER && - !(gfp_mask & __GFP_NOFAIL)) - goto nopage; + if (!(gfp_mask & __GFP_NOFAIL)) { + /* + * The oom killer is not called for high-order + * allocations that may fail, so if no progress + * is being made, there are no other options and + * retrying is unlikely to help. + */ + if (order > PAGE_ALLOC_COSTLY_ORDER) + goto nopage; + /* + * The oom killer is not called for lowmem + * allocations to prevent needlessly killing + * innocent tasks. + */ + if (high_zoneidx < ZONE_NORMAL) + goto nopage; + } goto restart; } _ Patches currently in -mm which might be from rientjes@xxxxxxxxxx are origin.patch linux-next.patch mempolicy-remove-redundant-code.patch oom-avoid-oom-killer-for-lowmem-allocations.patch oom-remove-unnecessary-code-and-cleanup.patch oom-default-to-killing-current-for-pagefault-ooms.patch oom-avoid-race-for-oom-killed-tasks-detaching-mm-prior-to-exit.patch oom-select_bad_process-check-pf_kthread-instead-of-mm-to-skip-kthreads.patch oom-select_bad_process-pf_exiting-check-should-take-mm-into-account.patch oom-introduce-find_lock_task_mm-to-fix-mm-false-positives.patch oom-oom_forkbomb_penalty-move-thread_group_cputime-out-of-task_lock.patch oom-hold-tasklist_lock-when-dumping-tasks.patch oom-give-current-access-to-memory-reserves-if-it-has-been-killed.patch oom-avoid-sending-exiting-tasks-a-sigkill.patch oom-clean-up-oom_kill_task.patch oom-clean-up-oom_badness.patch oom-select_bad_process-never-choose-tasks-with-badness-==-0.patch oom-avoid-divide-by-zero.patch mempolicy-remove-case-mpol_interleave-from-policy_zonelist.patch mempolicy-remove-redundant-check.patch mempolicy-dont-call-mpol_set_nodemask-when-no_context.patch mempolicy-lose-unnecessary-loop-variable-in-mpol_parse_str.patch mempolicy-rename-policy_types-and-cleanup-initialization.patch mempolicy-factor-mpol_shared_policy_init-return-paths.patch mempolicy-document-cpuset-interaction-with-tmpfs-mpol-mount-option.patch mempolicy-restructure-rebinding-mempolicy-functions.patch cpusetmm-fix-no-node-to-alloc-memory-when-changing-cpusets-mems.patch cpusetmm-fix-no-node-to-alloc-memory-when-changing-cpusets-mems-fix2.patch mm-default-to-node-zonelist-ordering-when-nodes-have-only-lowmem.patch mmcompaction-memory-compaction-core-do-not-schedule-work-on-other-cpus-for-compaction.patch memcg-oom-wakeup-filter.patch memcg-oom-wakeup-filter-update.patch memcg-oom-notifier.patch memcg-oom-notifier-update.patch memcg-oom-kill-disable-and-oom-status.patch memcg-oom-kill-disable-and-oom-status-update.patch memcg-make-oom-killer-a-no-op-when-no-killable-task-can-be-found.patch numa-add-generic-percpu-var-numa_node_id-implementation.patch numa-add-generic-percpu-var-numa_node_id-implementation-fix1.patch numa-add-generic-percpu-var-numa_node_id-implementation-fix2.patch numa-x86_64-use-generic-percpu-var-numa_node_id-implementation.patch numa-x86_64-use-generic-percpu-var-numa_node_id-implementation-fix1.patch numa-x86_64-use-generic-percpu-var-numa_node_id-implementation-fix2.patch numa-ia64-use-generic-percpu-var-numa_node_id-implementation.patch numa-introduce-numa_mem_id-effective-local-memory-node-id.patch numa-introduce-numa_mem_id-effective-local-memory-node-id-fix2.patch numa-introduce-numa_mem_id-effective-local-memory-node-id-fix3.patch numa-ia64-support-numa_mem_id-for-memoryless-nodes.patch numa-slab-use-numa_mem_id-for-slab-local-memory-node.patch numa-in-kernel-profiling-use-cpu_to_mem-for-per-cpu-allocations.patch numa-update-documentation-vm-numa-add-memoryless-node-info.patch numa-update-documentation-vm-numa-add-memoryless-node-info-fix1.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html