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-rw-r--r--mm/oom_kill.c124
1 files changed, 92 insertions, 32 deletions
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index b05ab8f2a562..78747afad6b0 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -58,15 +58,17 @@ unsigned long badness(struct task_struct *p, unsigned long uptime)
/*
* Processes which fork a lot of child processes are likely
- * a good choice. We add the vmsize of the children if they
+ * a good choice. We add half the vmsize of the children if they
* have an own mm. This prevents forking servers to flood the
- * machine with an endless amount of children
+ * machine with an endless amount of children. In case a single
+ * child is eating the vast majority of memory, adding only half
+ * to the parents will make the child our kill candidate of choice.
*/
list_for_each(tsk, &p->children) {
struct task_struct *chld;
chld = list_entry(tsk, struct task_struct, sibling);
if (chld->mm != p->mm && chld->mm)
- points += chld->mm->total_vm;
+ points += chld->mm->total_vm/2 + 1;
}
/*
@@ -131,17 +133,47 @@ unsigned long badness(struct task_struct *p, unsigned long uptime)
}
/*
+ * Types of limitations to the nodes from which allocations may occur
+ */
+#define CONSTRAINT_NONE 1
+#define CONSTRAINT_MEMORY_POLICY 2
+#define CONSTRAINT_CPUSET 3
+
+/*
+ * Determine the type of allocation constraint.
+ */
+static inline int constrained_alloc(struct zonelist *zonelist, gfp_t gfp_mask)
+{
+#ifdef CONFIG_NUMA
+ struct zone **z;
+ nodemask_t nodes = node_online_map;
+
+ for (z = zonelist->zones; *z; z++)
+ if (cpuset_zone_allowed(*z, gfp_mask))
+ node_clear((*z)->zone_pgdat->node_id,
+ nodes);
+ else
+ return CONSTRAINT_CPUSET;
+
+ if (!nodes_empty(nodes))
+ return CONSTRAINT_MEMORY_POLICY;
+#endif
+
+ return CONSTRAINT_NONE;
+}
+
+/*
* Simple selection loop. We chose the process with the highest
* number of 'points'. We expect the caller will lock the tasklist.
*
* (not docbooked, we don't want this one cluttering up the manual)
*/
-static struct task_struct * select_bad_process(void)
+static struct task_struct *select_bad_process(unsigned long *ppoints)
{
- unsigned long maxpoints = 0;
struct task_struct *g, *p;
struct task_struct *chosen = NULL;
struct timespec uptime;
+ *ppoints = 0;
do_posix_clock_monotonic_gettime(&uptime);
do_each_thread(g, p) {
@@ -169,9 +201,9 @@ static struct task_struct * select_bad_process(void)
return p;
points = badness(p, uptime.tv_sec);
- if (points > maxpoints || !chosen) {
+ if (points > *ppoints || !chosen) {
chosen = p;
- maxpoints = points;
+ *ppoints = points;
}
} while_each_thread(g, p);
return chosen;
@@ -182,7 +214,7 @@ static struct task_struct * select_bad_process(void)
* CAP_SYS_RAW_IO set, send SIGTERM instead (but it's unlikely that
* we select a process with CAP_SYS_RAW_IO set).
*/
-static void __oom_kill_task(task_t *p)
+static void __oom_kill_task(task_t *p, const char *message)
{
if (p->pid == 1) {
WARN_ON(1);
@@ -198,8 +230,8 @@ static void __oom_kill_task(task_t *p)
return;
}
task_unlock(p);
- printk(KERN_ERR "Out of Memory: Killed process %d (%s).\n",
- p->pid, p->comm);
+ printk(KERN_ERR "%s: Killed process %d (%s).\n",
+ message, p->pid, p->comm);
/*
* We give our sacrificial lamb high priority and access to
@@ -212,7 +244,7 @@ static void __oom_kill_task(task_t *p)
force_sig(SIGKILL, p);
}
-static struct mm_struct *oom_kill_task(task_t *p)
+static struct mm_struct *oom_kill_task(task_t *p, const char *message)
{
struct mm_struct *mm = get_task_mm(p);
task_t * g, * q;
@@ -224,35 +256,38 @@ static struct mm_struct *oom_kill_task(task_t *p)
return NULL;
}
- __oom_kill_task(p);
+ __oom_kill_task(p, message);
/*
* kill all processes that share the ->mm (i.e. all threads),
* but are in a different thread group
*/
do_each_thread(g, q)
if (q->mm == mm && q->tgid != p->tgid)
- __oom_kill_task(q);
+ __oom_kill_task(q, message);
while_each_thread(g, q);
return mm;
}
-static struct mm_struct *oom_kill_process(struct task_struct *p)
+static struct mm_struct *oom_kill_process(struct task_struct *p,
+ unsigned long points, const char *message)
{
struct mm_struct *mm;
struct task_struct *c;
struct list_head *tsk;
+ printk(KERN_ERR "Out of Memory: Kill process %d (%s) score %li and "
+ "children.\n", p->pid, p->comm, points);
/* Try to kill a child first */
list_for_each(tsk, &p->children) {
c = list_entry(tsk, struct task_struct, sibling);
if (c->mm == p->mm)
continue;
- mm = oom_kill_task(c);
+ mm = oom_kill_task(c, message);
if (mm)
return mm;
}
- return oom_kill_task(p);
+ return oom_kill_task(p, message);
}
/**
@@ -263,10 +298,11 @@ static struct mm_struct *oom_kill_process(struct task_struct *p)
* OR try to be smart about which process to kill. Note that we
* don't have to be perfect here, we just have to be good.
*/
-void out_of_memory(gfp_t gfp_mask, int order)
+void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask, int order)
{
struct mm_struct *mm = NULL;
- task_t * p;
+ task_t *p;
+ unsigned long points = 0;
if (printk_ratelimit()) {
printk("oom-killer: gfp_mask=0x%x, order=%d\n",
@@ -277,24 +313,48 @@ void out_of_memory(gfp_t gfp_mask, int order)
cpuset_lock();
read_lock(&tasklist_lock);
+
+ /*
+ * Check if there were limitations on the allocation (only relevant for
+ * NUMA) that may require different handling.
+ */
+ switch (constrained_alloc(zonelist, gfp_mask)) {
+ case CONSTRAINT_MEMORY_POLICY:
+ mm = oom_kill_process(current, points,
+ "No available memory (MPOL_BIND)");
+ break;
+
+ case CONSTRAINT_CPUSET:
+ mm = oom_kill_process(current, points,
+ "No available memory in cpuset");
+ break;
+
+ case CONSTRAINT_NONE:
retry:
- p = select_bad_process();
+ /*
+ * Rambo mode: Shoot down a process and hope it solves whatever
+ * issues we may have.
+ */
+ p = select_bad_process(&points);
- if (PTR_ERR(p) == -1UL)
- goto out;
+ if (PTR_ERR(p) == -1UL)
+ goto out;
- /* Found nothing?!?! Either we hang forever, or we panic. */
- if (!p) {
- read_unlock(&tasklist_lock);
- cpuset_unlock();
- panic("Out of memory and no killable processes...\n");
- }
+ /* Found nothing?!?! Either we hang forever, or we panic. */
+ if (!p) {
+ read_unlock(&tasklist_lock);
+ cpuset_unlock();
+ panic("Out of memory and no killable processes...\n");
+ }
- mm = oom_kill_process(p);
- if (!mm)
- goto retry;
+ mm = oom_kill_process(p, points, "Out of memory");
+ if (!mm)
+ goto retry;
+
+ break;
+ }
- out:
+out:
read_unlock(&tasklist_lock);
cpuset_unlock();
if (mm)
@@ -305,5 +365,5 @@ retry:
* retry to allocate memory unless "p" is current
*/
if (!test_thread_flag(TIF_MEMDIE))
- schedule_timeout_interruptible(1);
+ schedule_timeout_uninterruptible(1);
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-25 13:22:21 +0100