mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
* [patch] fix smp_processor_id() use in the cache-hot autodetector
@ 2005-11-15  8:42 Ingo Molnar
  0 siblings, 0 replies; only message in thread
From: Ingo Molnar @ 2005-11-15  8:42 UTC (permalink / raw)
  To: Andrew Morton; +Cc: Paul Jackson, linux-kernel


this patch fixes the DEBUG_PREEMPT warnings reported by Paul Jackson.  
The reason why raw_smp_processor_id() is fine here is that we dont care 
about the _precise_ CPU ID the boot process happens on, only about the 
quad. (the reason for this whole code is that NUMAQ doesnt like being 
migrated to a non-boot quad.) So we mark whatever CPU ID we happen to be 
on, and migrate back to it once calibration has finished.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

 kernel/sched.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

Index: linux/kernel/sched.c
===================================================================
--- linux.orig/kernel/sched.c
+++ linux/kernel/sched.c
@@ -5480,7 +5480,7 @@ __devinit static unsigned long long meas
 
 void __devinit calibrate_migration_costs(void)
 {
-	int cpu1 = -1, cpu2 = -1, cpu, orig_cpu = smp_processor_id();
+	int cpu1 = -1, cpu2 = -1, cpu, orig_cpu = raw_smp_processor_id();
 	struct sched_domain *sd;
 	unsigned long distance, max_distance = 0;
 	unsigned long long cost;
@@ -5567,7 +5567,7 @@ void __devinit calibrate_migration_costs
 	 * Move back to the original CPU. NUMA-Q gets confused
 	 * if we migrate to another quad during bootup.
 	 */
-	if (smp_processor_id() != orig_cpu) {
+	if (raw_smp_processor_id() != orig_cpu) {
 		cpumask_t mask = cpumask_of_cpu(orig_cpu),
 			saved_mask = current->cpus_allowed;
 

^ permalink raw reply	[flat|nested] only message in thread

only message in thread, other threads:[~2005-11-15  8:42 UTC | newest]

Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2005-11-15  8:42 [patch] fix smp_processor_id() use in the cache-hot autodetector Ingo Molnar

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®