The patch titled
percpu_counter: use this_cpu_ptr() instead of per_cpu_ptr()
has been added to the -mm tree. Its filename is
percpu_counter-use-this_cpu_ptr-instead-of-per_cpu_ptr.patch
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------------------------------------------------------
Subject: percpu_counter: use this_cpu_ptr() instead of per_cpu_ptr()
From: Christoph Lameter <cl@xxxxxxxxx>
this_cpu_ptr() avoids an array lookup and can use the percpu offset of the
local cpu directly.
Signed-off-by: Christoph Lameter <cl@xxxxxxxxx>
Cc: Eric Dumazet <eric.dumazet@xxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
lib/percpu_counter.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff -puN lib/percpu_counter.c~percpu_counter-use-this_cpu_ptr-instead-of-per_cpu_ptr lib/percpu_counter.c
--- a/lib/percpu_counter.c~percpu_counter-use-this_cpu_ptr-instead-of-per_cpu_ptr
+++ a/lib/percpu_counter.c
@@ -73,9 +73,9 @@ void __percpu_counter_add(struct percpu_
{
s64 count;
s32 *pcount;
- int cpu = get_cpu();
- pcount = per_cpu_ptr(fbc->counters, cpu);
+ preempt_disable();
+ pcount = this_cpu_ptr(fbc->counters);
count = *pcount + amount;
if (count >= batch || count <= -batch) {
spin_lock(&fbc->lock);
@@ -85,7 +85,7 @@ void __percpu_counter_add(struct percpu_
} else {
*pcount = count;
}
- put_cpu();
+ preempt_enable();
}
EXPORT_SYMBOL(__percpu_counter_add);
_
Patches currently in -mm which might be from cl@xxxxxxxxx are
linux-next.patch
mm-compaction-fix-compactpagefailed-counting.patch
mm-mempolicy-check-return-code-of-check_range.patch
percpu_counter-use-this_cpu_ptr-instead-of-per_cpu_ptr.patch
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