From 4bd9b9dc97e344670e9e5762399a07dcd5f15311 Mon Sep 17 00:00:00 2001 From: Chris J Arges Date: Wed, 15 Oct 2008 11:03:39 -0500 Subject: [PATCH] oprofile: hotplug cpu fix This patch addresses problems when hotplugging cpus while profiling. Instead of allocating only online cpus, all possible cpu buffers are allocated, which allows cpus to be onlined during operation. If a cpu is offlined before profiling is shutdown wq_sync_buffer checks for this condition then cancels this work and does not sync this buffer. Signed-off-by: Chris J Arges Signed-off-by: Robert Richter --- drivers/oprofile/cpu_buffer.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/oprofile/cpu_buffer.c b/drivers/oprofile/cpu_buffer.c index 5a178065cfa0..67bcc1c95e60 100644 --- a/drivers/oprofile/cpu_buffer.c +++ b/drivers/oprofile/cpu_buffer.c @@ -39,7 +39,7 @@ void free_cpu_buffers(void) { int i; - for_each_online_cpu(i) { + for_each_possible_cpu(i) { vfree(per_cpu(cpu_buffer, i).buffer); per_cpu(cpu_buffer, i).buffer = NULL; } @@ -51,7 +51,7 @@ int alloc_cpu_buffers(void) unsigned long buffer_size = fs_cpu_buffer_size; - for_each_online_cpu(i) { + for_each_possible_cpu(i) { struct oprofile_cpu_buffer *b = &per_cpu(cpu_buffer, i); b->buffer = vmalloc_node(sizeof(struct op_sample) * buffer_size, @@ -350,6 +350,11 @@ static void wq_sync_buffer(struct work_struct *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; + } } sync_buffer(b->cpu);