The patch titled
Add irq protection in the percpu-counters cpu-hotplug-callback path
has been removed from the -mm tree. Its filename was
add-irq-protection-in-the-percpu-counters-cpu-hotplug-callback-path.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
Subject: Add irq protection in the percpu-counters cpu-hotplug-callback path
From: Gautham R Shenoy <ego@xxxxxxxxxx>
Some of the per-cpu counters and thus their locks are accessed from IRQ
contexts. This can cause a deadlock if it interrupts a cpu-offline thread
which is transferring a dead-cpu's counts to the global counter.
Add appropriate IRQ protection in the cpu-hotplug callback path.
Signed-off-by: Gautham R Shenoy <ego@xxxxxxxxxx>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
lib/percpu_counter.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff -puN lib/percpu_counter.c~add-irq-protection-in-the-percpu-counters-cpu-hotplug-callback-path lib/percpu_counter.c
--- a/lib/percpu_counter.c~add-irq-protection-in-the-percpu-counters-cpu-hotplug-callback-path
+++ a/lib/percpu_counter.c
@@ -124,12 +124,13 @@ static int __cpuinit percpu_counter_hotc
mutex_lock(&percpu_counters_lock);
list_for_each_entry(fbc, &percpu_counters, list) {
s32 *pcount;
+ unsigned long flags;
- spin_lock(&fbc->lock);
+ spin_lock_irqsave(&fbc->lock, flags);
pcount = per_cpu_ptr(fbc->counters, cpu);
fbc->count += *pcount;
*pcount = 0;
- spin_unlock(&fbc->lock);
+ spin_unlock_irqrestore(&fbc->lock, flags);
}
mutex_unlock(&percpu_counters_lock);
return NOTIFY_OK;
_
Patches currently in -mm which might be from ego@xxxxxxxxxx are
origin.patch
-
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
