3.3-stable patches

added patches:
	android-lowmemorykiller-remove-task-handoff-notifier.patch

diff --git a/queue-3.3/android-lowmemorykiller-remove-task-handoff-notifier.patch b/queue-3.3/android-lowmemorykiller-remove-task-handoff-notifier.patch
new file mode 100644 (file)
index 0000000..ab02e4d
--- /dev/null
+++ b/queue-3.3/android-lowmemorykiller-remove-task-handoff-notifier.patch
@@ -0,0 +1,138 @@
+From 83dbbdbb38666e20a75fad2294cf1df77c52f121 Mon Sep 17 00:00:00 2001
+From: David Rientjes <rientjes@google.com>
+Date: Mon, 9 Apr 2012 16:56:18 -0700
+Subject: android, lowmemorykiller: remove task handoff notifier
+
+From: David Rientjes <rientjes@google.com>
+
+commit 83dbbdbb38666e20a75fad2294cf1df77c52f121 upstream.
+
+The task handoff notifier leaks task_struct since it never gets freed
+after the callback returns NOTIFY_OK, which means it is responsible for
+doing so.
+
+It turns out the lowmemorykiller actually doesn't need this notifier at
+all.  It's used to prevent unnecessary killing by waiting for a thread
+to exit as a result of lowmem_shrink(), however, it's possible to do
+this in the same way the kernel oom killer works by setting TIF_MEMDIE
+and avoid killing if we're still waiting for it to exit.
+
+The kernel oom killer will already automatically set TIF_MEMDIE for
+threads that are attempting to allocate memory that have a fatal signal.
+The thread selected by lowmem_shrink() will have such a signal after the
+lowmemorykiller sends it a SIGKILL, so this won't result in an
+unnecessary use of memory reserves for the thread to exit.
+
+This has the added benefit that we don't have to rely on
+CONFIG_PROFILING to prevent needlessly killing tasks.
+
+Reported-by: Werner Landgraf <w.landgraf@ru.ru>
+Signed-off-by: David Rientjes <rientjes@google.com>
+Acked-by: Colin Cross <ccross@android.com>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/staging/android/lowmemorykiller.c |   47 +++---------------------------
+ 1 file changed, 6 insertions(+), 41 deletions(-)
+
+--- a/drivers/staging/android/lowmemorykiller.c
++++ b/drivers/staging/android/lowmemorykiller.c
+@@ -53,7 +53,6 @@ static size_t lowmem_minfree[6] = {
+ };
+ static int lowmem_minfree_size = 4;
+ 
+-static struct task_struct *lowmem_deathpending;
+ static unsigned long lowmem_deathpending_timeout;
+ 
+ #define lowmem_print(level, x...)                     \
+@@ -62,24 +61,6 @@ static unsigned long lowmem_deathpending
+                       printk(x);                      \
+       } while (0)
+ 
+-static int
+-task_notify_func(struct notifier_block *self, unsigned long val, void *data);
+-
+-static struct notifier_block task_nb = {
+-      .notifier_call  = task_notify_func,
+-};
+-
+-static int
+-task_notify_func(struct notifier_block *self, unsigned long val, void *data)
+-{
+-      struct task_struct *task = data;
+-
+-      if (task == lowmem_deathpending)
+-              lowmem_deathpending = NULL;
+-
+-      return NOTIFY_OK;
+-}
+-
+ static int lowmem_shrink(struct shrinker *s, struct shrink_control *sc)
+ {
+       struct task_struct *p;
+@@ -95,19 +76,6 @@ static int lowmem_shrink(struct shrinker
+       int other_file = global_page_state(NR_FILE_PAGES) -
+                                               global_page_state(NR_SHMEM);
+ 
+-      /*
+-       * If we already have a death outstanding, then
+-       * bail out right away; indicating to vmscan
+-       * that we have nothing further to offer on
+-       * this pass.
+-       *
+-       * Note: Currently you need CONFIG_PROFILING
+-       * for this to work correctly.
+-       */
+-      if (lowmem_deathpending &&
+-          time_before_eq(jiffies, lowmem_deathpending_timeout))
+-              return 0;
+-
+       if (lowmem_adj_size < array_size)
+               array_size = lowmem_adj_size;
+       if (lowmem_minfree_size < array_size)
+@@ -140,6 +108,11 @@ static int lowmem_shrink(struct shrinker
+               struct signal_struct *sig;
+               int oom_adj;
+ 
++              if (test_tsk_thread_flag(p, TIF_MEMDIE) &&
++                  time_before_eq(jiffies, lowmem_deathpending_timeout)) {
++                      read_unlock(&tasklist_lock);
++                      return 0;
++              }
+               task_lock(p);
+               mm = p->mm;
+               sig = p->signal;
+@@ -173,15 +146,9 @@ static int lowmem_shrink(struct shrinker
+               lowmem_print(1, "send sigkill to %d (%s), adj %d, size %d\n",
+                            selected->pid, selected->comm,
+                            selected_oom_adj, selected_tasksize);
+-              /*
+-               * If CONFIG_PROFILING is off, then we don't want to stall
+-               * the killer by setting lowmem_deathpending.
+-               */
+-#ifdef CONFIG_PROFILING
+-              lowmem_deathpending = selected;
+               lowmem_deathpending_timeout = jiffies + HZ;
+-#endif
+               force_sig(SIGKILL, selected);
++              set_tsk_thread_flag(selected, TIF_MEMDIE);
+               rem -= selected_tasksize;
+       }
+       lowmem_print(4, "lowmem_shrink %lu, %x, return %d\n",
+@@ -197,7 +164,6 @@ static struct shrinker lowmem_shrinker =
+ 
+ static int __init lowmem_init(void)
+ {
+-      task_handoff_register(&task_nb);
+       register_shrinker(&lowmem_shrinker);
+       return 0;
+ }
+@@ -205,7 +171,6 @@ static int __init lowmem_init(void)
+ static void __exit lowmem_exit(void)
+ {
+       unregister_shrinker(&lowmem_shrinker);
+-      task_handoff_unregister(&task_nb);
+ }
+ 
+ module_param_named(cost, lowmem_shrinker.seeks, int, S_IRUGO | S_IWUSR);

diff --git a/queue-3.3/series b/queue-3.3/series
index a3f1ac7d99af21d554c00bc662c8c25e3f37244d..d79cf2fa5c3ff617dad055968aa919c5efa073ce 100644 (file)
--- a/queue-3.3/series
+++ b/queue-3.3/series
@@ -60,3 +60,4 @@ sysctl-fix-write-access-to-dmesg_restrict-kptr_restrict.patch
 regmap-prevent-division-by-zero-in-rbtree_show.patch
 modpost-fix-modpost-license-checking-of-vmlinux.o.patch
 mfd-fix-section-mismatch-warning-for-da9052-spi.patch
+android-lowmemorykiller-remove-task-handoff-notifier.patch