path: root/arch/powerpc/platforms/pseries/hotplug-cpu.c
diff options
authorSebastien Dugue <sebastien.dugue@bull.net>2008-11-27 00:59:52 +0000
committerPaul Mackerras <paulus@samba.org>2008-12-23 15:13:27 +1100
commitb906cfa397fdef8decbd36467b1f63c830a0bf2b (patch)
tree1a3fa1f47f82476c8945661ea01e7be8ffb88713 /arch/powerpc/platforms/pseries/hotplug-cpu.c
parentfad7b9b51e21a97e9e2662f1b51869ed2d209097 (diff)
powerpc/pseries: Fix cpu hotplug
Currently, pseries_cpu_die() calls msleep() while polling RTAS for the status of the dying cpu. However, if the cpu that is going down also happens to be the one doing the tick then we're hosed as the tick_do_timer_cpu 'baton' is only passed later on in tick_shutdown() when _cpu_down() does the CPU_DEAD notification. Therefore jiffies won't be updated anymore. This replaces that msleep() with a cpu_relax() to make sure we're not going to schedule at that point. With this patch my test box survives a 100k iterations hotplug stress test on _all_ cpus, whereas without it, it quickly dies after ~50 iterations. Signed-off-by: Sebastien Dugue <sebastien.dugue@bull.net> Cc: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch/powerpc/platforms/pseries/hotplug-cpu.c')
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c
index 1f032483c02..a20ead87153 100644
--- a/arch/powerpc/platforms/pseries/hotplug-cpu.c
+++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c
@@ -116,7 +116,7 @@ static void pseries_cpu_die(unsigned int cpu)
cpu_status = query_cpu_stopped(pcpu);
if (cpu_status == 0 || cpu_status == -1)
- msleep(200);
+ cpu_relax();
if (cpu_status != 0) {
printk("Querying DEAD? cpu %i (%i) shows %i\n",