X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;ds=sidebyside;f=mm%2Foom_kill.c;h=175a67a78a99e7b0368dfba11edf9888bc049674;hb=7669f54c55df225cbb2db939a6c9f111445ffc1c;hp=2846a58e5de980ddf0716740c8c5c29689610939;hpb=b4416d2bea007f07f2e74cdc4cb64042ec996c83;p=safe%2Fjmp%2Flinux-2.6 diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 2846a58..175a67a 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -31,14 +31,13 @@ int sysctl_panic_on_oom; int sysctl_oom_kill_allocating_task; int sysctl_oom_dump_tasks; -static DEFINE_SPINLOCK(zone_scan_mutex); +static DEFINE_SPINLOCK(zone_scan_lock); /* #define DEBUG */ /** * badness - calculate a numeric value for how bad this task has been * @p: task struct of which task we should calculate * @uptime: current uptime in seconds - * @mem: target memory controller * * The formula used is relatively simple and documented inline in the * function. The main rationale is that we want to select a good task @@ -56,9 +55,10 @@ static DEFINE_SPINLOCK(zone_scan_mutex); unsigned long badness(struct task_struct *p, unsigned long uptime) { - unsigned long points, cpu_time, run_time, s; + unsigned long points, cpu_time, run_time; struct mm_struct *mm; struct task_struct *child; + int oom_adj; task_lock(p); mm = p->mm; @@ -66,6 +66,11 @@ unsigned long badness(struct task_struct *p, unsigned long uptime) task_unlock(p); return 0; } + oom_adj = mm->oom_adj; + if (oom_adj == OOM_DISABLE) { + task_unlock(p); + return 0; + } /* * The memory size of the process is the basis for the badness. @@ -111,12 +116,10 @@ unsigned long badness(struct task_struct *p, unsigned long uptime) else run_time = 0; - s = int_sqrt(cpu_time); - if (s) - points /= s; - s = int_sqrt(int_sqrt(run_time)); - if (s) - points /= s; + if (cpu_time) + points /= int_sqrt(cpu_time); + if (run_time) + points /= int_sqrt(int_sqrt(run_time)); /* * Niced processes are most likely less important, so double @@ -129,8 +132,8 @@ unsigned long badness(struct task_struct *p, unsigned long uptime) * Superuser processes are usually more important, so we make it * less likely that we kill those. */ - if (has_capability(p, CAP_SYS_ADMIN) || - has_capability(p, CAP_SYS_RESOURCE)) + if (has_capability_noaudit(p, CAP_SYS_ADMIN) || + has_capability_noaudit(p, CAP_SYS_RESOURCE)) points /= 4; /* @@ -139,7 +142,7 @@ unsigned long badness(struct task_struct *p, unsigned long uptime) * tend to only have this flag set on applications they think * of as important. */ - if (has_capability(p, CAP_SYS_RAWIO)) + if (has_capability_noaudit(p, CAP_SYS_RAWIO)) points /= 4; /* @@ -151,15 +154,15 @@ unsigned long badness(struct task_struct *p, unsigned long uptime) points /= 8; /* - * Adjust the score by oomkilladj. + * Adjust the score by oom_adj. */ - if (p->oomkilladj) { - if (p->oomkilladj > 0) { + if (oom_adj) { + if (oom_adj > 0) { if (!points) points = 1; - points <<= p->oomkilladj; + points <<= oom_adj; } else - points >>= -(p->oomkilladj); + points >>= -(oom_adj); } #ifdef DEBUG @@ -254,11 +257,8 @@ static struct task_struct *select_bad_process(unsigned long *ppoints, *ppoints = ULONG_MAX; } - if (p->oomkilladj == OOM_DISABLE) - continue; - points = badness(p, uptime.tv_sec); - if (points > *ppoints || !chosen) { + if (points > *ppoints) { chosen = p; *ppoints = points; } @@ -287,22 +287,27 @@ static void dump_tasks(const struct mem_cgroup *mem) printk(KERN_INFO "[ pid ] uid tgid total_vm rss cpu oom_adj " "name\n"); do_each_thread(g, p) { - /* - * total_vm and rss sizes do not exist for tasks with a - * detached mm so there's no need to report them. - */ - if (!p->mm) - continue; + struct mm_struct *mm; + if (mem && !task_in_mem_cgroup(p, mem)) continue; if (!thread_group_leader(p)) continue; task_lock(p); + mm = p->mm; + if (!mm) { + /* + * total_vm and rss sizes do not exist for tasks with no + * mm so there's no need to report them; they can't be + * oom killed anyway. + */ + task_unlock(p); + continue; + } printk(KERN_INFO "[%5d] %5d %5d %8lu %8lu %3d %3d %s\n", - p->pid, p->uid, p->tgid, p->mm->total_vm, - get_mm_rss(p->mm), (int)task_cpu(p), p->oomkilladj, - p->comm); + p->pid, __task_cred(p)->uid, p->tgid, mm->total_vm, + get_mm_rss(mm), (int)task_cpu(p), mm->oom_adj, p->comm); task_unlock(p); } while_each_thread(g, p); } @@ -320,11 +325,8 @@ static void __oom_kill_task(struct task_struct *p, int verbose) return; } - if (!p->mm) { - WARN_ON(1); - printk(KERN_WARNING "tried to kill an mm-less task!\n"); + if (!p->mm) return; - } if (verbose) printk(KERN_ERR "Killed process %d (%s)\n", @@ -346,28 +348,13 @@ static int oom_kill_task(struct task_struct *p) struct mm_struct *mm; struct task_struct *g, *q; + task_lock(p); mm = p->mm; - - /* 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 (mm == NULL) + if (!mm || mm->oom_adj == OOM_DISABLE) { + task_unlock(p); return 1; - - /* - * Don't kill the process if any threads are set to OOM_DISABLE - */ - do_each_thread(g, q) { - if (q->mm == mm && q->oomkilladj == OOM_DISABLE) - return 1; - } while_each_thread(g, q); - + } + task_unlock(p); __oom_kill_task(p, 1); /* @@ -390,10 +377,15 @@ static int oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order, struct task_struct *c; if (printk_ratelimit()) { + task_lock(current); printk(KERN_WARNING "%s invoked oom-killer: " - "gfp_mask=0x%x, order=%d, oomkilladj=%d\n", - current->comm, gfp_mask, order, current->oomkilladj); + "gfp_mask=0x%x, order=%d, oom_adj=%d\n", + current->comm, gfp_mask, order, + current->mm ? current->mm->oom_adj : OOM_DISABLE); + cpuset_print_task_mems_allowed(current); + task_unlock(current); dump_stack(); + mem_cgroup_print_oom_info(mem, current); show_mem(); if (sysctl_oom_dump_tasks) dump_tasks(mem); @@ -402,8 +394,9 @@ static int oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order, /* * If the task is already exiting, don't alarm the sysadmin or kill * its children or threads, just set TIF_MEMDIE so it can die quickly + * if its mm is still attached. */ - if (p->flags & PF_EXITING) { + if (p->mm && (p->flags & PF_EXITING)) { __oom_kill_task(p, 0); return 0; } @@ -427,7 +420,6 @@ void mem_cgroup_out_of_memory(struct mem_cgroup *mem, gfp_t gfp_mask) unsigned long points = 0; struct task_struct *p; - cgroup_lock(); read_lock(&tasklist_lock); retry: p = select_bad_process(&points, mem); @@ -442,7 +434,6 @@ retry: goto retry; out: read_unlock(&tasklist_lock); - cgroup_unlock(); } #endif @@ -471,7 +462,7 @@ int try_set_zone_oom(struct zonelist *zonelist, gfp_t gfp_mask) struct zone *zone; int ret = 1; - spin_lock(&zone_scan_mutex); + spin_lock(&zone_scan_lock); for_each_zone_zonelist(zone, z, zonelist, gfp_zone(gfp_mask)) { if (zone_is_oom_locked(zone)) { ret = 0; @@ -481,7 +472,7 @@ int try_set_zone_oom(struct zonelist *zonelist, gfp_t gfp_mask) for_each_zone_zonelist(zone, z, zonelist, gfp_zone(gfp_mask)) { /* - * Lock each zone in the zonelist under zone_scan_mutex so a + * Lock each zone in the zonelist under zone_scan_lock so a * parallel invocation of try_set_zone_oom() doesn't succeed * when it shouldn't. */ @@ -489,7 +480,7 @@ int try_set_zone_oom(struct zonelist *zonelist, gfp_t gfp_mask) } out: - spin_unlock(&zone_scan_mutex); + spin_unlock(&zone_scan_lock); return ret; } @@ -503,11 +494,80 @@ void clear_zonelist_oom(struct zonelist *zonelist, gfp_t gfp_mask) struct zoneref *z; struct zone *zone; - spin_lock(&zone_scan_mutex); + spin_lock(&zone_scan_lock); for_each_zone_zonelist(zone, z, zonelist, gfp_zone(gfp_mask)) { zone_clear_flag(zone, ZONE_OOM_LOCKED); } - spin_unlock(&zone_scan_mutex); + spin_unlock(&zone_scan_lock); +} + +/* + * Must be called with tasklist_lock held for read. + */ +static void __out_of_memory(gfp_t gfp_mask, int order) +{ + struct task_struct *p; + unsigned long points; + + if (sysctl_oom_kill_allocating_task) + if (!oom_kill_process(current, gfp_mask, order, 0, NULL, + "Out of memory (oom_kill_allocating_task)")) + return; +retry: + /* + * Rambo mode: Shoot down a process and hope it solves whatever + * issues we may have. + */ + p = select_bad_process(&points, NULL); + + if (PTR_ERR(p) == -1UL) + return; + + /* Found nothing?!?! Either we hang forever, or we panic. */ + if (!p) { + read_unlock(&tasklist_lock); + panic("Out of memory and no killable processes...\n"); + } + + if (oom_kill_process(p, gfp_mask, order, points, NULL, + "Out of memory")) + goto retry; +} + +/* + * pagefault handler calls into here because it is out of memory but + * doesn't know exactly how or why. + */ +void pagefault_out_of_memory(void) +{ + unsigned long freed = 0; + + blocking_notifier_call_chain(&oom_notify_list, 0, &freed); + if (freed > 0) + /* Got some memory back in the last second. */ + return; + + /* + * If this is from memcg, oom-killer is already invoked. + * and not worth to go system-wide-oom. + */ + if (mem_cgroup_oom_called(current)) + goto rest_and_return; + + if (sysctl_panic_on_oom) + panic("out of memory from page fault. panic_on_oom is selected.\n"); + + read_lock(&tasklist_lock); + __out_of_memory(0, 0); /* unknown gfp_mask and order */ + read_unlock(&tasklist_lock); + + /* + * Give "p" a good chance of killing itself before we + * retry to allocate memory. + */ +rest_and_return: + if (!test_thread_flag(TIF_MEMDIE)) + schedule_timeout_uninterruptible(1); } /** @@ -523,8 +583,6 @@ void clear_zonelist_oom(struct zonelist *zonelist, gfp_t gfp_mask) */ void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask, int order) { - struct task_struct *p; - unsigned long points = 0; unsigned long freed = 0; enum oom_constraint constraint; @@ -545,7 +603,7 @@ void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask, int order) switch (constraint) { case CONSTRAINT_MEMORY_POLICY: - oom_kill_process(current, gfp_mask, order, points, NULL, + oom_kill_process(current, gfp_mask, order, 0, NULL, "No available memory (MPOL_BIND)"); break; @@ -554,35 +612,10 @@ void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask, int order) panic("out of memory. panic_on_oom is selected\n"); /* Fall-through */ case CONSTRAINT_CPUSET: - if (sysctl_oom_kill_allocating_task) { - oom_kill_process(current, gfp_mask, order, points, NULL, - "Out of memory (oom_kill_allocating_task)"); - break; - } -retry: - /* - * Rambo mode: Shoot down a process and hope it solves whatever - * issues we may have. - */ - p = select_bad_process(&points, NULL); - - if (PTR_ERR(p) == -1UL) - goto out; - - /* Found nothing?!?! Either we hang forever, or we panic. */ - if (!p) { - read_unlock(&tasklist_lock); - panic("Out of memory and no killable processes...\n"); - } - - if (oom_kill_process(p, gfp_mask, order, points, NULL, - "Out of memory")) - goto retry; - + __out_of_memory(gfp_mask, order); break; } -out: read_unlock(&tasklist_lock); /*