linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
* [PATCH 2/3 staging-next] oom: Add notification for oom_score_adj
@ 2017-02-09 13:21 peter enderborg
  2017-02-09 19:40 ` Michal Hocko
  0 siblings, 1 reply; 3+ messages in thread
From: peter enderborg @ 2017-02-09 13:21 UTC (permalink / raw)
  To: devel, Greg Kroah-Hartman, linux-kernel,
	Arve Hjønnevåg, Riley Andrews, Linus Torvalds,
	linux-mm

This adds subscribtion for changes in oom_score_adj, this
value is important to android systems. For task that uses
oom_score_adj they read the task list. This can be long
and need rcu locks and has a impact on the system. Let
the user track the changes based on oom_score_adj changes
and keep them in their own context so they do their actions
with minimal system impact.

Signed-off-by: Peter Enderborg <peter.enderborg@sonymobile.com>
---
  fs/proc/base.c                     | 13 +++++++
  include/linux/oom_score_notifier.h | 47 ++++++++++++++++++++++++
  kernel/Makefile                    |  1 +
  kernel/fork.c                      |  6 +++
  kernel/oom_score_notifier.c        | 75 ++++++++++++++++++++++++++++++++++++++
  mm/Kconfig                         |  9 +++++
  6 files changed, 151 insertions(+)
  create mode 100644 include/linux/oom_score_notifier.h
  create mode 100644 kernel/oom_score_notifier.c

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 87c9a9a..60c2d9b 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -87,6 +87,7 @@
  #include <linux/slab.h>
  #include <linux/flex_array.h>
  #include <linux/posix-timers.h>
+#include <linux/oom_score_notifier.h>
  #ifdef CONFIG_HARDWALL
  #include <asm/hardwall.h>
  #endif
@@ -1057,6 +1058,7 @@ static int __set_oom_adj(struct file *file, int oom_adj, bool legacy)
      static DEFINE_MUTEX(oom_adj_mutex);
      struct mm_struct *mm = NULL;
      struct task_struct *task;
+    int old_oom_score_adj;
      int err = 0;

      task = get_proc_task(file_inode(file));
@@ -1102,9 +1104,20 @@ static int __set_oom_adj(struct file *file, int oom_adj, bool legacy)
          }
      }

+    old_oom_score_adj = task->signal->oom_score_adj;
      task->signal->oom_score_adj = oom_adj;
      if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE))
          task->signal->oom_score_adj_min = (short)oom_adj;
+
+#ifdef CONFIG_OOM_SCORE_NOTIFIER
+    err = oom_score_notify_update(task, old_oom_score_adj);
+    if (err) {
+        /* rollback and error handle. */
+        task->signal->oom_score_adj = old_oom_score_adj;
+        goto err_unlock;
+    }
+#endif
+
      trace_oom_score_adj_update(task);

      if (mm) {
diff --git a/include/linux/oom_score_notifier.h b/include/linux/oom_score_notifier.h
new file mode 100644
index 0000000..c5cea47
--- /dev/null
+++ b/include/linux/oom_score_notifier.h
@@ -0,0 +1,47 @@
+/*
+ *  oom_score_notifier interface
+ *  Copyright (C) 2017 Sony Mobile Communications Inc.
+ *
+ *  Author: Peter Enderborg <peter.enderborg@sonymobile.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  published by the Free Software Foundation.
+ */
+
+#ifndef _LINUX_OOM_SCORE_NOTIFIER_H
+#define _LINUX_OOM_SCORE_NOTIFIER_H
+
+#ifdef CONFIG_OOM_SCORE_NOTIFIER
+
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+
+enum osn_msg_type {
+    OSN_NEW,
+    OSN_FREE,
+    OSN_UPDATE
+};
+
+extern struct atomic_notifier_head oom_score_notifier;
+extern int oom_score_notifier_register(struct notifier_block *n);
+extern int oom_score_notifier_unregister(struct notifier_block *n);
+extern int oom_score_notify_free(struct task_struct *tsk);
+extern int oom_score_notify_new(struct task_struct *tsk);
+extern int oom_score_notify_update(struct task_struct *tsk, int old_score);
+
+struct oom_score_notifier_struct {
+    struct task_struct *tsk;
+    int old_score;
+};
+
+#else
+
+#define oom_score_notify_free(t)  do {} while (0)
+#define oom_score_notify_new(t) false
+#define oom_score_notify_update(t, s) do {} while (0)
+
+#endif /* CONFIG_OOM_SCORE_NOTIFIER */
+
+#endif /* _LINUX_OOM_SCORE_NOTIFIER_H */
diff --git a/kernel/Makefile b/kernel/Makefile
index 12c679f..747c66c 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -91,6 +91,7 @@ obj-$(CONFIG_SYSCTL) += utsname_sysctl.o
  obj-$(CONFIG_TASK_DELAY_ACCT) += delayacct.o
  obj-$(CONFIG_TASKSTATS) += taskstats.o tsacct.o
  obj-$(CONFIG_TRACEPOINTS) += tracepoint.o
+obj-$(CONFIG_OOM_SCORE_NOTIFIER) += oom_score_notifier.o
  obj-$(CONFIG_LATENCYTOP) += latencytop.o
  obj-$(CONFIG_ELFCORE) += elfcore.o
  obj-$(CONFIG_FUNCTION_TRACER) += trace/
diff --git a/kernel/fork.c b/kernel/fork.c
index 11c5c8a..f8a1a89 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -73,6 +73,7 @@
  #include <linux/signalfd.h>
  #include <linux/uprobes.h>
  #include <linux/aio.h>
+#include <linux/oom_score_notifier.h>
  #include <linux/compiler.h>
  #include <linux/sysctl.h>
  #include <linux/kcov.h>
@@ -391,6 +392,7 @@ void __put_task_struct(struct task_struct *tsk)
      exit_creds(tsk);
      delayacct_tsk_free(tsk);
      put_signal_struct(tsk->signal);
+    oom_score_notify_free(tsk);

      if (!profile_handoff_task(tsk))
          free_task(tsk);
@@ -1790,6 +1792,10 @@ static __latent_entropy struct task_struct *copy_process(

          init_task_pid(p, PIDTYPE_PID, pid);
          if (thread_group_leader(p)) {
+            retval = oom_score_notify_new(p);
+            if (retval)
+                goto bad_fork_cancel_cgroup;
+
              init_task_pid(p, PIDTYPE_PGID, task_pgrp(current));
              init_task_pid(p, PIDTYPE_SID, task_session(current));

diff --git a/kernel/oom_score_notifier.c b/kernel/oom_score_notifier.c
new file mode 100644
index 0000000..6dd6d8e
--- /dev/null
+++ b/kernel/oom_score_notifier.c
@@ -0,0 +1,75 @@
+/*
+ *  oom_score_notifier interface
+ *  Copyright (C) 2017 Sony Mobile Communications Inc.
+ *
+ *  Author: Peter Enderborg <peter.enderborg@sonymobile.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  published by the Free Software Foundation.
+ */
+
+
+#include <linux/notifier.h>
+#include <linux/oom_score_notifier.h>
+
+#ifdef CONFIG_OOM_SCORE_NOTIFIER
+ATOMIC_NOTIFIER_HEAD(oom_score_notifier);
+
+int oom_score_notifier_register(struct notifier_block *n)
+{
+    return atomic_notifier_chain_register(&oom_score_notifier, n);
+}
+EXPORT_SYMBOL_GPL(oom_score_notifier_register);
+
+int oom_score_notifier_unregister(struct notifier_block *n)
+{
+    return atomic_notifier_chain_unregister(&oom_score_notifier, n);
+}
+EXPORT_SYMBOL_GPL(oom_score_notifier_unregister);
+
+int oom_score_notify_free(struct task_struct *tsk)
+{
+    struct oom_score_notifier_struct osns;
+
+    osns.tsk = tsk;
+    return notifier_to_errno(atomic_notifier_call_chain(
+        &oom_score_notifier, OSN_FREE, &osns));
+}
+EXPORT_SYMBOL_GPL(oom_score_notify_free);
+
+int oom_score_notify_new(struct task_struct *tsk)
+{
+    struct oom_score_notifier_struct osns;
+
+    osns.tsk = tsk;
+    return notifier_to_errno(atomic_notifier_call_chain(
+        &oom_score_notifier, OSN_NEW, &osns));
+}
+EXPORT_SYMBOL_GPL(oom_score_notify_new);
+
+int oom_score_notify_update(struct task_struct *tsk, int old_score)
+{
+    struct oom_score_notifier_struct osns;
+
+    osns.tsk = tsk;
+    osns.old_score = old_score;
+    return notifier_to_errno(atomic_notifier_call_chain(&oom_score_notifier,
+                                OSN_UPDATE, &osns));
+}
+EXPORT_SYMBOL_GPL(oom_score_notify_update);
+
+#else
+inline int oom_score_notifier_register(struct notifier_block *n) { return 0; };
+inline int oom_score_notifier_unregister(struct notifier_block *n)
+{
+    return 0;
+};
+inline int oom_score_notify_free(struct task_struct *tsk) { return 0; };
+inline int oom_score_notify_new(struct task_struct *tsk) { return 0; };
+inline int oom_score_notify_update(struct task_struct *tsk, int old_score)
+{
+    return 0;
+};
+
+#endif
diff --git a/mm/Kconfig b/mm/Kconfig
index 9b8fccb..fb2a5d2 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -327,6 +327,15 @@ config MMU_NOTIFIER
      bool
      select SRCU

+config OOM_SCORE_NOTIFIER
+    bool "OOM score notifier"
+    default n
+    help
+      This create a notifier for process oom_score_adj status.
+      It create events for new, updated or freed tasks and
+      are used to build a mirrored task list in
+      lowmemmorykiller.
+
  config KSM
      bool "Enable KSM for page merging"
      depends on MMU
-- 
2.4.2


--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

^ permalink raw reply	[flat|nested] 3+ messages in thread
* [PATCH 1/3 staging-next] android: Collect statistics from lowmemorykiller
@ 2017-02-14 16:09 peter.enderborg
  2017-02-14 16:09 ` [PATCH 2/3 staging-next] oom: Add notification for oom_score_adj peter.enderborg
  0 siblings, 1 reply; 3+ messages in thread
From: peter.enderborg @ 2017-02-14 16:09 UTC (permalink / raw)
  To: devel, gregkh, linux-kernel, arve, riandrews, torvalds, linux-mm
  Cc: Peter Enderborg

From: Peter Enderborg <peter.enderborg@sonymobile.com>

This collects stats for shrinker calls and how much
waste work we do within the lowmemorykiller.

Signed-off-by: Peter Enderborg <peter.enderborg@sonymobile.com>
---
 drivers/staging/android/Kconfig                 | 11 ++++
 drivers/staging/android/Makefile                |  1 +
 drivers/staging/android/lowmemorykiller.c       |  9 ++-
 drivers/staging/android/lowmemorykiller_stats.c | 85 +++++++++++++++++++++++++
 drivers/staging/android/lowmemorykiller_stats.h | 29 +++++++++
 5 files changed, 134 insertions(+), 1 deletion(-)
 create mode 100644 drivers/staging/android/lowmemorykiller_stats.c
 create mode 100644 drivers/staging/android/lowmemorykiller_stats.h

diff --git a/drivers/staging/android/Kconfig b/drivers/staging/android/Kconfig
index 6c00d6f..96e86c7 100644
--- a/drivers/staging/android/Kconfig
+++ b/drivers/staging/android/Kconfig
@@ -24,6 +24,17 @@ config ANDROID_LOW_MEMORY_KILLER
 	  scripts (/init.rc), and it defines priority values with minimum free memory size
 	  for each priority.
 
+config ANDROID_LOW_MEMORY_KILLER_STATS
+	bool "Android Low Memory Killer: collect statistics"
+	depends on ANDROID_LOW_MEMORY_KILLER
+	default n
+	help
+	  Create a file in /proc/lmkstats that includes
+	  collected statistics about kills, scans and counts
+	  and  interaction with the shrinker. Its content
+	  will be different depeding on lmk implementation used.
+
+
 source "drivers/staging/android/ion/Kconfig"
 
 endif # if ANDROID
diff --git a/drivers/staging/android/Makefile b/drivers/staging/android/Makefile
index 7ed1be7..d710eb2 100644
--- a/drivers/staging/android/Makefile
+++ b/drivers/staging/android/Makefile
@@ -4,3 +4,4 @@ obj-y					+= ion/
 
 obj-$(CONFIG_ASHMEM)			+= ashmem.o
 obj-$(CONFIG_ANDROID_LOW_MEMORY_KILLER)	+= lowmemorykiller.o
+obj-$(CONFIG_ANDROID_LOW_MEMORY_KILLER_STATS)	+= lowmemorykiller_stats.o
diff --git a/drivers/staging/android/lowmemorykiller.c b/drivers/staging/android/lowmemorykiller.c
index ec3b665..15c1b38 100644
--- a/drivers/staging/android/lowmemorykiller.c
+++ b/drivers/staging/android/lowmemorykiller.c
@@ -42,6 +42,7 @@
 #include <linux/rcupdate.h>
 #include <linux/profile.h>
 #include <linux/notifier.h>
+#include "lowmemorykiller_stats.h"
 
 static u32 lowmem_debug_level = 1;
 static short lowmem_adj[6] = {
@@ -72,6 +73,7 @@ static unsigned long lowmem_deathpending_timeout;
 static unsigned long lowmem_count(struct shrinker *s,
 				  struct shrink_control *sc)
 {
+	lmk_inc_stats(LMK_COUNT);
 	return global_node_page_state(NR_ACTIVE_ANON) +
 		global_node_page_state(NR_ACTIVE_FILE) +
 		global_node_page_state(NR_INACTIVE_ANON) +
@@ -95,6 +97,7 @@ static unsigned long lowmem_scan(struct shrinker *s, struct shrink_control *sc)
 				global_node_page_state(NR_SHMEM) -
 				total_swapcache_pages();
 
+	lmk_inc_stats(LMK_SCAN);
 	if (lowmem_adj_size < array_size)
 		array_size = lowmem_adj_size;
 	if (lowmem_minfree_size < array_size)
@@ -134,6 +137,7 @@ static unsigned long lowmem_scan(struct shrinker *s, struct shrink_control *sc)
 		if (task_lmk_waiting(p) &&
 		    time_before_eq(jiffies, lowmem_deathpending_timeout)) {
 			task_unlock(p);
+			lmk_inc_stats(LMK_TIMEOUT);
 			rcu_read_unlock();
 			return 0;
 		}
@@ -179,7 +183,9 @@ static unsigned long lowmem_scan(struct shrinker *s, struct shrink_control *sc)
 			     other_free * (long)(PAGE_SIZE / 1024));
 		lowmem_deathpending_timeout = jiffies + HZ;
 		rem += selected_tasksize;
-	}
+		lmk_inc_stats(LMK_KILL);
+	} else
+		lmk_inc_stats(LMK_WASTE);
 
 	lowmem_print(4, "lowmem_scan %lu, %x, return %lu\n",
 		     sc->nr_to_scan, sc->gfp_mask, rem);
@@ -196,6 +202,7 @@ static struct shrinker lowmem_shrinker = {
 static int __init lowmem_init(void)
 {
 	register_shrinker(&lowmem_shrinker);
+	init_procfs_lmk();
 	return 0;
 }
 device_initcall(lowmem_init);
diff --git a/drivers/staging/android/lowmemorykiller_stats.c b/drivers/staging/android/lowmemorykiller_stats.c
new file mode 100644
index 0000000..673691c
--- /dev/null
+++ b/drivers/staging/android/lowmemorykiller_stats.c
@@ -0,0 +1,85 @@
+/*
+ *  lowmemorykiller_stats
+ *
+ *  Copyright (C) 2017 Sony Mobile Communications Inc.
+ *
+ *  Author: Peter Enderborg <peter.enderborg@sonymobile.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  published by the Free Software Foundation.
+ */
+/* This code is bookkeeping of statistical information
+ * from lowmemorykiller and provide a node in proc "/proc/lmkstats".
+ */
+
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include "lowmemorykiller_stats.h"
+
+struct lmk_stats {
+	atomic_long_t scans; /* counter as in shrinker scans */
+	atomic_long_t kills; /* the number of sigkills sent */
+	atomic_long_t waste; /* the numer of extensive calls that did
+			      * not lead to anything
+			      */
+	atomic_long_t timeout; /* counter for shrinker calls that needed
+				* to be cancelled due to pending kills
+				*/
+	atomic_long_t count; /* number of shrinker count calls */
+	atomic_long_t unknown; /* internal */
+} st;
+
+void lmk_inc_stats(int key)
+{
+	switch (key) {
+	case LMK_SCAN:
+		atomic_long_inc(&st.scans);
+		break;
+	case LMK_KILL:
+		atomic_long_inc(&st.kills);
+		break;
+	case LMK_WASTE:
+		atomic_long_inc(&st.waste);
+		break;
+	case LMK_TIMEOUT:
+		atomic_long_inc(&st.timeout);
+		break;
+	case LMK_COUNT:
+		atomic_long_inc(&st.count);
+		break;
+	default:
+		atomic_long_inc(&st.unknown);
+		break;
+	}
+}
+
+static int lmk_proc_show(struct seq_file *m, void *v)
+{
+	seq_printf(m, "kill: %ld\n", atomic_long_read(&st.kills));
+	seq_printf(m, "scan: %ld\n", atomic_long_read(&st.scans));
+	seq_printf(m, "waste: %ld\n", atomic_long_read(&st.waste));
+	seq_printf(m, "timeout: %ld\n", atomic_long_read(&st.timeout));
+	seq_printf(m, "count: %ld\n", atomic_long_read(&st.count));
+	seq_printf(m, "unknown: %ld (internal)\n",
+		   atomic_long_read(&st.unknown));
+
+	return 0;
+}
+
+static int lmk_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, lmk_proc_show, PDE_DATA(inode));
+}
+
+static const struct file_operations lmk_proc_fops = {
+	.open		= lmk_proc_open,
+	.read		= seq_read,
+	.release	= single_release
+};
+
+int __init init_procfs_lmk(void)
+{
+	proc_create_data(LMK_PROCFS_NAME, 0444, NULL, &lmk_proc_fops, NULL);
+	return 0;
+}
diff --git a/drivers/staging/android/lowmemorykiller_stats.h b/drivers/staging/android/lowmemorykiller_stats.h
new file mode 100644
index 0000000..abeb6924
--- /dev/null
+++ b/drivers/staging/android/lowmemorykiller_stats.h
@@ -0,0 +1,29 @@
+/*
+ *  lowmemorykiller_stats interface
+ *
+ *  Copyright (C) 2017 Sony Mobile Communications Inc.
+ *
+ *  Author: Peter Enderborg <peter.enderborg@sonymobile.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  published by the Free Software Foundation.
+ */
+
+enum  lmk_kill_stats {
+	LMK_SCAN = 1,
+	LMK_KILL = 2,
+	LMK_WASTE = 3,
+	LMK_TIMEOUT = 4,
+	LMK_COUNT = 5
+};
+
+#define LMK_PROCFS_NAME "lmkstats"
+
+#ifdef CONFIG_ANDROID_LOW_MEMORY_KILLER_STATS
+void lmk_inc_stats(int key);
+int __init init_procfs_lmk(void);
+#else
+static inline void lmk_inc_stats(int key) { return; };
+static inline int __init init_procfs_lmk(void) { return 0; };
+#endif
-- 
2.4.2

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

^ permalink raw reply	[flat|nested] 3+ messages in thread
end of thread, other threads:[~2017-02-14 16:09 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-02-09 13:21 [PATCH 2/3 staging-next] oom: Add notification for oom_score_adj peter enderborg
2017-02-09 19:40 ` Michal Hocko
2017-02-14 16:09 [PATCH 1/3 staging-next] android: Collect statistics from lowmemorykiller peter.enderborg
2017-02-14 16:09 ` [PATCH 2/3 staging-next] oom: Add notification for oom_score_adj peter.enderborg

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox