The patch titled Subject: mm, oom: force oom kill on sysrq+f has been removed from the -mm tree. Its filename was mm-oom-force-oom-kill-on-sysrqf.patch This patch was dropped because it was merged into mainline or a subsystem tree The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ From: David Rientjes <rientjes@xxxxxxxxxx> Subject: mm, oom: force oom kill on sysrq+f The oom killer chooses not to kill a thread if: - an eligible thread has already been oom killed and has yet to exit, and - an eligible thread is exiting but has yet to free all its memory and is not the thread attempting to currently allocate memory. SysRq+F manually invokes the global oom killer to kill a memory-hogging task. This is normally done as a last resort to free memory when no progress is being made or to test the oom killer itself. For both uses, we always want to kill a thread and never defer. This patch causes SysRq+F to always kill an eligible thread and can be used to force a kill even if another oom killed thread has failed to exit. Signed-off-by: David Rientjes <rientjes@xxxxxxxxxx> Acked-by: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> Acked-by: Pekka Enberg <penberg@xxxxxxxxxx> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/tty/sysrq.c | 2 +- include/linux/oom.h | 2 +- mm/oom_kill.c | 17 ++++++++++------- mm/page_alloc.c | 2 +- 4 files changed, 13 insertions(+), 10 deletions(-) diff -puN drivers/tty/sysrq.c~mm-oom-force-oom-kill-on-sysrqf drivers/tty/sysrq.c --- a/drivers/tty/sysrq.c~mm-oom-force-oom-kill-on-sysrqf +++ a/drivers/tty/sysrq.c @@ -346,7 +346,7 @@ static struct sysrq_key_op sysrq_term_op static void moom_callback(struct work_struct *ignored) { - out_of_memory(node_zonelist(0, GFP_KERNEL), GFP_KERNEL, 0, NULL); + out_of_memory(node_zonelist(0, GFP_KERNEL), GFP_KERNEL, 0, NULL, true); } static DECLARE_WORK(moom_work, moom_callback); diff -puN include/linux/oom.h~mm-oom-force-oom-kill-on-sysrqf include/linux/oom.h --- a/include/linux/oom.h~mm-oom-force-oom-kill-on-sysrqf +++ a/include/linux/oom.h @@ -49,7 +49,7 @@ extern int try_set_zonelist_oom(struct z extern void clear_zonelist_oom(struct zonelist *zonelist, gfp_t gfp_flags); extern void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask, - int order, nodemask_t *mask); + int order, nodemask_t *mask, bool force_kill); extern int register_oom_notifier(struct notifier_block *nb); extern int unregister_oom_notifier(struct notifier_block *nb); diff -puN mm/oom_kill.c~mm-oom-force-oom-kill-on-sysrqf mm/oom_kill.c --- a/mm/oom_kill.c~mm-oom-force-oom-kill-on-sysrqf +++ a/mm/oom_kill.c @@ -310,7 +310,7 @@ static enum oom_constraint constrained_a */ static struct task_struct *select_bad_process(unsigned int *ppoints, unsigned long totalpages, struct mem_cgroup *memcg, - const nodemask_t *nodemask) + const nodemask_t *nodemask, bool force_kill) { struct task_struct *g, *p; struct task_struct *chosen = NULL; @@ -336,7 +336,8 @@ static struct task_struct *select_bad_pr if (test_tsk_thread_flag(p, TIF_MEMDIE)) { if (unlikely(frozen(p))) __thaw_task(p); - return ERR_PTR(-1UL); + if (!force_kill) + return ERR_PTR(-1UL); } if (!p->mm) continue; @@ -354,7 +355,7 @@ static struct task_struct *select_bad_pr if (p == current) { chosen = p; *ppoints = 1000; - } else { + } else if (!force_kill) { /* * If this task is not being ptraced on exit, * then wait for it to finish before killing @@ -572,7 +573,7 @@ void mem_cgroup_out_of_memory(struct mem check_panic_on_oom(CONSTRAINT_MEMCG, gfp_mask, 0, NULL); limit = mem_cgroup_get_limit(memcg) >> PAGE_SHIFT; read_lock(&tasklist_lock); - p = select_bad_process(&points, limit, memcg, NULL); + p = select_bad_process(&points, limit, memcg, NULL, false); if (p && PTR_ERR(p) != -1UL) oom_kill_process(p, gfp_mask, 0, points, limit, memcg, NULL, "Memory cgroup out of memory"); @@ -687,6 +688,7 @@ static void clear_system_oom(void) * @gfp_mask: memory allocation flags * @order: amount of memory being requested as a power of 2 * @nodemask: nodemask passed to page allocator + * @force_kill: true if a task must be killed, even if others are exiting * * If we run out of memory, we have the choice between either * killing a random task (bad), letting the system crash (worse) @@ -694,7 +696,7 @@ static void clear_system_oom(void) * don't have to be perfect here, we just have to be good. */ void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask, - int order, nodemask_t *nodemask) + int order, nodemask_t *nodemask, bool force_kill) { const nodemask_t *mpol_mask; struct task_struct *p; @@ -738,7 +740,8 @@ void out_of_memory(struct zonelist *zone goto out; } - p = select_bad_process(&points, totalpages, NULL, mpol_mask); + p = select_bad_process(&points, totalpages, NULL, mpol_mask, + force_kill); /* Found nothing?!?! Either we hang forever, or we panic. */ if (!p) { dump_header(NULL, gfp_mask, order, NULL, mpol_mask); @@ -770,7 +773,7 @@ out: void pagefault_out_of_memory(void) { if (try_set_system_oom()) { - out_of_memory(NULL, 0, 0, NULL); + out_of_memory(NULL, 0, 0, NULL, false); clear_system_oom(); } if (!test_thread_flag(TIF_MEMDIE)) diff -puN mm/page_alloc.c~mm-oom-force-oom-kill-on-sysrqf mm/page_alloc.c --- a/mm/page_alloc.c~mm-oom-force-oom-kill-on-sysrqf +++ a/mm/page_alloc.c @@ -1968,7 +1968,7 @@ __alloc_pages_may_oom(gfp_t gfp_mask, un goto out; } /* Exhausted what can be done so it's blamo time */ - out_of_memory(zonelist, gfp_mask, order, nodemask); + out_of_memory(zonelist, gfp_mask, order, nodemask, false); out: clear_zonelist_oom(zonelist, gfp_mask); _ Patches currently in -mm which might be from rientjes@xxxxxxxxxx are origin.patch linux-next.patch signal-give-send_sig_forced-more-power-to-beat-signal_unkillable.patch signal-cosmetic-s-from_ancestor_ns-force-in-prepare_signal-paths.patch signal-oom_kill_task-use-send_sig_forced-instead-of-force_sig.patch signal-zap_pid_ns_processes-s-send_sig_noinfo-send_sig_forced.patch usermodehelper-introduce-umh_completesub_info.patch usermodehelper-implement-umh_killable.patch usermodehelper-kill-umh_wait-renumber-umh_-constants.patch usermodehelper-____call_usermodehelper-doesnt-need-do_exit.patch kmod-introduce-call_modprobe-helper.patch kmod-make-__request_module-killable.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