oprofile: Remove 'WQ on CPUx, prefer CPUy' warning
Under certain workloads we see the following warnings:
WQ on CPU0, prefer CPU1
WQ on CPU0, prefer CPU2
WQ on CPU0, prefer CPU3
It warns the user that the wq to access a per-cpu buffers runs not on
the same cpu. This happens if the wq is rescheduled on a different cpu
than where the buffer is located. This was probably implemented to
detect performance issues. Not sure if there actually is one as the
buffers are copied to a single buffer anyway which should be the
actual bottleneck.
We wont change WQ implementation. Since a user can do nothing the
warning is pointless. Removing it.
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Robert Richter <robert.richter@amd.com>
diff --git a/drivers/oprofile/cpu_buffer.c b/drivers/oprofile/cpu_buffer.c
index b8ef8dd..8aa73fa 100644
--- a/drivers/oprofile/cpu_buffer.c
+++ b/drivers/oprofile/cpu_buffer.c
@@ -451,14 +451,9 @@
{
struct oprofile_cpu_buffer *b =
container_of(work, struct oprofile_cpu_buffer, work.work);
- if (b->cpu != smp_processor_id()) {
- printk(KERN_DEBUG "WQ on CPU%d, prefer CPU%d\n",
- smp_processor_id(), b->cpu);
-
- if (!cpu_online(b->cpu)) {
- cancel_delayed_work(&b->work);
- return;
- }
+ if (b->cpu != smp_processor_id() && !cpu_online(b->cpu)) {
+ cancel_delayed_work(&b->work);
+ return;
}
sync_buffer(b->cpu);