The patch titled oom: remove unnecessary code and cleanup has been removed from the -mm tree. Its filename was oom-remove-unnecessary-code-and-cleanup.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: remove unnecessary code and cleanup From: David Rientjes <rientjes@xxxxxxxxxx> Remove the redundancy in __oom_kill_task() since: - init can never be passed to this function: it will never be PF_EXITING or selectable from select_bad_process(), and - it will never be passed a task from oom_kill_task() without an ->mm and we're unconcerned about detachment from exiting tasks, there's no reason to protect them against SIGKILL or access to memory reserves. Also moves the kernel log message to a higher level since the verbosity is not always emitted here; we need not print an error message if an exiting task is given a longer timeslice. Signed-off-by: David Rientjes <rientjes@xxxxxxxxxx> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> Cc: Rik van Riel <riel@xxxxxxxxxx> Cc: Nick Piggin <npiggin@xxxxxxx> Cc: Balbir Singh <balbir@xxxxxxxxxxxxxxxxxx> Cc: Minchan Kim <minchan.kim@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/oom_kill.c | 64 ++++++++++++------------------------------------ 1 file changed, 16 insertions(+), 48 deletions(-) diff -puN mm/oom_kill.c~oom-remove-unnecessary-code-and-cleanup mm/oom_kill.c --- a/mm/oom_kill.c~oom-remove-unnecessary-code-and-cleanup +++ a/mm/oom_kill.c @@ -427,67 +427,35 @@ static void dump_header(struct task_stru dump_tasks(mem); } -#define K(x) ((x) << (PAGE_SHIFT-10)) - /* - * Send SIGKILL to the selected process irrespective of CAP_SYS_RAW_IO - * flag though it's unlikely that we select a process with CAP_SYS_RAW_IO - * set. + * Give the oom killed task high priority and access to memory reserves so that + * it may quickly exit and free its memory. */ -static void __oom_kill_task(struct task_struct *p, int verbose) +static void __oom_kill_task(struct task_struct *p) { - if (is_global_init(p)) { - WARN_ON(1); - printk(KERN_WARNING "tried to kill init!\n"); - return; - } - - task_lock(p); - if (!p->mm) { - WARN_ON(1); - printk(KERN_WARNING "tried to kill an mm-less task %d (%s)!\n", - task_pid_nr(p), p->comm); - task_unlock(p); - return; - } - - if (verbose) - printk(KERN_ERR "Killed process %d (%s) " - "vsz:%lukB, anon-rss:%lukB, file-rss:%lukB\n", - task_pid_nr(p), p->comm, - K(p->mm->total_vm), - K(get_mm_counter(p->mm, MM_ANONPAGES)), - K(get_mm_counter(p->mm, MM_FILEPAGES))); - task_unlock(p); - - /* - * We give our sacrificial lamb high priority and access to - * all the memory it needs. That way it should be able to - * exit() and clear out its resources quickly... - */ p->rt.time_slice = HZ; set_tsk_thread_flag(p, TIF_MEMDIE); - force_sig(SIGKILL, p); } +#define K(x) ((x) << (PAGE_SHIFT-10)) static int oom_kill_task(struct task_struct *p) { - /* WARNING: mm may not be dereferenced since we did not obtain its - * value from get_task_mm(p). This is OK since all we need to do is - * compare mm to q->mm below. - * - * Furthermore, even if mm contains a non-NULL value, p->mm may - * change to NULL at any time since we do not hold task_lock(p). - * However, this is of no concern to us. - */ - if (!p->mm || p->signal->oom_score_adj == OOM_SCORE_ADJ_MIN) + task_lock(p); + if (!p->mm || p->signal->oom_score_adj == OOM_SCORE_ADJ_MIN) { + task_unlock(p); return 1; + } + pr_err("Killed process %d (%s) total-vm:%lukB, anon-rss:%lukB, file-rss:%lukB\n", + task_pid_nr(p), p->comm, K(p->mm->total_vm), + K(get_mm_counter(p->mm, MM_ANONPAGES)), + K(get_mm_counter(p->mm, MM_FILEPAGES))); + task_unlock(p); - __oom_kill_task(p, 1); - + __oom_kill_task(p); return 0; } +#undef K static int oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order, unsigned int points, unsigned long totalpages, @@ -506,7 +474,7 @@ static int oom_kill_process(struct task_ * its children or threads, just set TIF_MEMDIE so it can die quickly */ if (p->flags & PF_EXITING) { - __oom_kill_task(p, 0); + __oom_kill_task(p); return 0; } _ Patches currently in -mm which might be from rientjes@xxxxxxxxxx are origin.patch linux-next.patch mempolicy-remove-redundant-code.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