diff options
| author | Oleg Nesterov <oleg@redhat.com> | 2013-06-20 17:50:09 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-07-03 10:59:01 -0700 |
| commit | ed0b72ac1e4361d9aaf2922adfba4a263cc37e03 (patch) | |
| tree | a650fbbca90c4af7fd3bc08ca549b6d08995b6bc /kernel | |
| parent | 630493e2e96ab876b8085a3352e255d2f56be75c (diff) | |
hw_breakpoint: Use cpu_possible_mask in {reserve,release}_bp_slot()
commit c790b0ad23f427c7522ffed264706238c57c007e upstream.
fetch_bp_busy_slots() and toggle_bp_slot() use
for_each_online_cpu(), this is obviously wrong wrt cpu_up() or
cpu_down(), we can over/under account the per-cpu numbers.
For example:
# echo 0 >> /sys/devices/system/cpu/cpu1/online
# perf record -e mem:0x10 -p 1 &
# echo 1 >> /sys/devices/system/cpu/cpu1/online
# perf record -e mem:0x10,mem:0x10,mem:0x10,mem:0x10 -C1 -a &
# taskset -p 0x2 1
triggers the same WARN_ONCE("Can't find any breakpoint slot") in
arch_install_hw_breakpoint().
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/20130620155009.GA6327@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/events/hw_breakpoint.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/events/hw_breakpoint.c b/kernel/events/hw_breakpoint.c index bb38c4d3ee12..fc8bfcf3a3da 100644 --- a/kernel/events/hw_breakpoint.c +++ b/kernel/events/hw_breakpoint.c @@ -147,7 +147,7 @@ fetch_bp_busy_slots(struct bp_busy_slots *slots, struct perf_event *bp, return; } - for_each_online_cpu(cpu) { + for_each_possible_cpu(cpu) { unsigned int nr; nr = per_cpu(nr_cpu_bp_pinned[type], cpu); @@ -233,7 +233,7 @@ toggle_bp_slot(struct perf_event *bp, bool enable, enum bp_type_idx type, if (cpu >= 0) { toggle_bp_task_slot(bp, cpu, enable, type, weight); } else { - for_each_online_cpu(cpu) + for_each_possible_cpu(cpu) toggle_bp_task_slot(bp, cpu, enable, type, weight); } |