From 647f2bdf4a00dbcaa8964286501d68e7d2e6da93 Mon Sep 17 00:00:00 2001 From: David Rientjes Date: Wed, 21 Mar 2012 16:33:46 -0700 Subject: [PATCH] mm, oom: fold oom_kill_task() into oom_kill_process() oom_kill_task() has a single caller, so fold it into its parent function, oom_kill_process(). Slightly reduces the number of lines in the oom killer. Acked-by: KOSAKI Motohiro Reviewed-by: KAMEZAWA Hiroyuki Signed-off-by: David Rientjes Acked-by: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/oom_kill.c | 85 +++++++++++++++++++++++---------------------------- 1 file changed, 38 insertions(+), 47 deletions(-) diff --git a/mm/oom_kill.c b/mm/oom_kill.c index a26695fe8833..d402b2c1040e 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -434,52 +434,6 @@ static void dump_header(struct task_struct *p, gfp_t gfp_mask, int order, } #define K(x) ((x) << (PAGE_SHIFT-10)) -static void oom_kill_task(struct task_struct *p) -{ - struct task_struct *q; - struct mm_struct *mm; - - p = find_lock_task_mm(p); - if (!p) - return; - - /* mm cannot be safely dereferenced after task_unlock(p) */ - mm = p->mm; - - 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); - - /* - * Kill all user processes sharing p->mm in other thread groups, if any. - * They don't get access to memory reserves or a higher scheduler - * priority, though, to avoid depletion of all memory or task - * starvation. This prevents mm->mmap_sem livelock when an oom killed - * task cannot exit because it requires the semaphore and its contended - * by another thread trying to allocate memory itself. That thread will - * now get access to memory reserves since it has a pending fatal - * signal. - */ - for_each_process(q) - if (q->mm == mm && !same_thread_group(q, p) && - !(q->flags & PF_KTHREAD)) { - if (q->signal->oom_score_adj == OOM_SCORE_ADJ_MIN) - continue; - - task_lock(q); /* Protect ->comm from prctl() */ - pr_err("Kill process %d (%s) sharing same memory\n", - task_pid_nr(q), q->comm); - task_unlock(q); - force_sig(SIGKILL, q); - } - - set_tsk_thread_flag(p, TIF_MEMDIE); - force_sig(SIGKILL, p); -} -#undef K - static void oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order, unsigned int points, unsigned long totalpages, struct mem_cgroup *memcg, nodemask_t *nodemask, @@ -488,6 +442,7 @@ static void oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order, struct task_struct *victim = p; struct task_struct *child; struct task_struct *t = p; + struct mm_struct *mm; unsigned int victim_points = 0; if (printk_ratelimit()) @@ -531,8 +486,44 @@ static void oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order, } } while_each_thread(p, t); - oom_kill_task(victim); + victim = find_lock_task_mm(victim); + if (!victim) + return; + + /* mm cannot safely be dereferenced after task_unlock(victim) */ + mm = victim->mm; + pr_err("Killed process %d (%s) total-vm:%lukB, anon-rss:%lukB, file-rss:%lukB\n", + task_pid_nr(victim), victim->comm, K(victim->mm->total_vm), + K(get_mm_counter(victim->mm, MM_ANONPAGES)), + K(get_mm_counter(victim->mm, MM_FILEPAGES))); + task_unlock(victim); + + /* + * Kill all user processes sharing victim->mm in other thread groups, if + * any. They don't get access to memory reserves, though, to avoid + * depletion of all memory. This prevents mm->mmap_sem livelock when an + * oom killed thread cannot exit because it requires the semaphore and + * its contended by another thread trying to allocate memory itself. + * That thread will now get access to memory reserves since it has a + * pending fatal signal. + */ + for_each_process(p) + if (p->mm == mm && !same_thread_group(p, victim) && + !(p->flags & PF_KTHREAD)) { + if (p->signal->oom_score_adj == OOM_SCORE_ADJ_MIN) + continue; + + task_lock(p); /* Protect ->comm from prctl() */ + pr_err("Kill process %d (%s) sharing same memory\n", + task_pid_nr(p), p->comm); + task_unlock(p); + force_sig(SIGKILL, p); + } + + set_tsk_thread_flag(victim, TIF_MEMDIE); + force_sig(SIGKILL, victim); } +#undef K /* * Determines whether the kernel must panic because of the panic_on_oom sysctl. -- 2.30.2