[PATCH v11 2/2] Add the missing information in dump_header

From: ufo19890607
Date: Sat Jun 30 2018 - 12:39:41 EST


From: yuzhoujian <yuzhoujian@xxxxxxxxxxxxxxx>

Add a new func mem_cgroup_print_oom_context to print missing information
for the system-wide oom report which includes the oom memcg that has
reached its limit, task memcg that contains the killed task.

Signed-off-by: yuzhoujian <yuzhoujian@xxxxxxxxxxxxxxx>
---
include/linux/memcontrol.h | 15 ++++++++++++---
mm/memcontrol.c | 36 ++++++++++++++++++++++--------------
mm/oom_kill.c | 10 ++++++----
3 files changed, 40 insertions(+), 21 deletions(-)

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 6c6fb116e925..90855880bca2 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -28,6 +28,7 @@
#include <linux/eventfd.h>
#include <linux/mm.h>
#include <linux/vmstat.h>
+#include <linux/oom.h>
#include <linux/writeback.h>
#include <linux/page-flags.h>

@@ -491,8 +492,10 @@ void mem_cgroup_handle_over_high(void);

unsigned long mem_cgroup_get_max(struct mem_cgroup *memcg);

-void mem_cgroup_print_oom_info(struct mem_cgroup *memcg,
- struct task_struct *p);
+void mem_cgroup_print_oom_context(struct mem_cgroup *memcg,
+ struct task_struct *p);
+
+void mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg);

static inline void mem_cgroup_oom_enable(void)
{
@@ -903,7 +906,13 @@ static inline unsigned long mem_cgroup_get_max(struct mem_cgroup *memcg)
}

static inline void
-mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p)
+mem_cgroup_print_oom_context(struct mem_cgroup *memcg,
+ struct task_struct *p)
+{
+}
+
+static inline void
+mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg)
{
}

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index e6f0d5ef320a..18deea974cfd 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1119,32 +1119,40 @@ static const char *const memcg1_stat_names[] = {

#define K(x) ((x) << (PAGE_SHIFT-10))
/**
- * mem_cgroup_print_oom_info: Print OOM information relevant to memory controller.
- * @memcg: The memory cgroup that went over limit
+ * mem_cgroup_print_oom_context: Print OOM context information relevant to
+ * memory controller.
+ * @memcg: The origin memory cgroup that went over limit
* @p: Task that is going to be killed
*
* NOTE: @memcg and @p's mem_cgroup can be different when hierarchy is
* enabled
*/
-void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p)
+void mem_cgroup_print_oom_context(struct mem_cgroup *memcg, struct task_struct *p)
{
- struct mem_cgroup *iter;
- unsigned int i;
+ struct cgroup *origin_cgrp, *kill_cgrp;

rcu_read_lock();
-
+ if (memcg) {
+ pr_cont(",oom_memcg=");
+ pr_cont_cgroup_path(memcg->css.cgroup);
+ } else
+ pr_cont(",global_oom");
if (p) {
- pr_info("Task in ");
+ pr_cont(",task_memcg=");
pr_cont_cgroup_path(task_cgroup(p, memory_cgrp_id));
- pr_cont(" killed as a result of limit of ");
- } else {
- pr_info("Memory limit reached of cgroup ");
}
-
- pr_cont_cgroup_path(memcg->css.cgroup);
- pr_cont("\n");
-
rcu_read_unlock();
+}
+
+/**
+ * mem_cgroup_print_oom_meminfo: Print OOM memory information relevant to
+ * memory controller.
+ * @memcg: The memory cgroup that went over limit
+ */
+void mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg)
+{
+ struct mem_cgroup *iter;
+ unsigned int i;

pr_info("memory: usage %llukB, limit %llukB, failcnt %lu\n",
K((u64)page_counter_read(&memcg->memory)),
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index f9b08e455fd1..e990c45d2e7d 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -424,12 +424,14 @@ static void dump_header(struct oom_control *oc, struct task_struct *p)
dump_stack();

/* one line summary of the oom killer context. */
- pr_info("oom-kill:constraint=%s,nodemask=%*pbl,task=%s,pid=%5d,uid=%5d",
+ pr_info("oom-kill:constraint=%s,nodemask=%*pbl",
oom_constraint_text[oc->constraint],
- nodemask_pr_args(oc->nodemask),
- p->comm, p->pid, from_kuid(&init_user_ns, task_uid(p)));
+ nodemask_pr_args(oc->nodemask));
+ mem_cgroup_print_oom_context(oc->memcg, p);
+ pr_cont(",task=%s,pid=%5d,uid=%5d\n", p->comm, p->pid,
+ from_kuid(&init_user_ns, task_uid(p)));
if (is_memcg_oom(oc))
- mem_cgroup_print_oom_info(oc->memcg, p);
+ mem_cgroup_print_oom_meminfo(oc->memcg);
else {
show_mem(SHOW_MEM_FILTER_NODES, oc->nodemask);
if (is_dump_unreclaim_slabs())
--
2.14.1