[PATCH 1/1] MM: slqb, fix per_cpu access

From: Jiri Slaby
Date: Mon Nov 02 2009 - 03:49:31 EST


We cannot use the same local variable name as the declared per_cpu
variable since commit "percpu: remove per_cpu__ prefix."

Otherwise we would see crashes like:
general protection fault: 0000 [#1] SMP
last sysfs file:
CPU 1
Modules linked in:
Pid: 1, comm: swapper Tainted: G W 2.6.32-rc5-mm1_64 #860
RIP: 0010:[<ffffffff8142ff94>] [<ffffffff8142ff94>] start_cpu_timer+0x2b/0x87
...

Use slqb_ prefix for the global variable so that we don't collide
even with the rest of the kernel (s390 and alpha need this).

Signed-off-by: Jiri Slaby <jirislaby@xxxxxxxxx>
Cc: Nick Piggin <npiggin@xxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxxxxxxxxxxxxx>
---
mm/slqb.c | 10 ++++++----
1 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/mm/slqb.c b/mm/slqb.c
index e745d9a..e4bb53f 100644
--- a/mm/slqb.c
+++ b/mm/slqb.c
@@ -2766,11 +2766,12 @@ out:
schedule_delayed_work(work, round_jiffies_relative(3*HZ));
}

-static DEFINE_PER_CPU(struct delayed_work, cache_trim_work);
+static DEFINE_PER_CPU(struct delayed_work, slqb_cache_trim_work);

static void __cpuinit start_cpu_timer(int cpu)
{
- struct delayed_work *cache_trim_work = &per_cpu(cache_trim_work, cpu);
+ struct delayed_work *cache_trim_work = &per_cpu(slqb_cache_trim_work,
+ cpu);

/*
* When this gets called from do_initcalls via cpucache_init(),
@@ -3136,8 +3137,9 @@ static int __cpuinit slab_cpuup_callback(struct notifier_block *nfb,

case CPU_DOWN_PREPARE:
case CPU_DOWN_PREPARE_FROZEN:
- cancel_rearming_delayed_work(&per_cpu(cache_trim_work, cpu));
- per_cpu(cache_trim_work, cpu).work.func = NULL;
+ cancel_rearming_delayed_work(&per_cpu(slqb_cache_trim_work,
+ cpu));
+ per_cpu(slqb_cache_trim_work, cpu).work.func = NULL;
break;

case CPU_UP_CANCELED:
--
1.6.4.2

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