diff options
author | Deng-Cheng Zhu <dczhu@mips.com> | 2011-11-21 19:28:46 (GMT) |
---|---|---|
committer | Ralf Baechle <ralf@linux-mips.org> | 2011-12-07 22:04:41 (GMT) |
commit | 74653ccf231a3100dd03e16e7a4178868a37332e (patch) | |
tree | d4709f0b9a7fdfcd9a70d9a6b34dfd3f8f906270 /arch/mips/kernel | |
parent | 2c1b54d331bde7afbf8da24789cce2402e155495 (diff) | |
download | linux-74653ccf231a3100dd03e16e7a4178868a37332e.tar.xz |
MIPS/Perf-events: Remove erroneous check on active_events
Port the following patch for ARM by Mark Rutland:
- 57ce9bb39b476accf8fba6e16aea67ed76ea523d
ARM: 6902/1: perf: Remove erroneous check on active_events
When initialising a PMU, there is a check to protect against races with
other CPUs filling all of the available event slots. Since armpmu_add
checks that an event can be scheduled, we do not need to do this at
initialisation time. Furthermore the current code is broken because it
assumes that atomic_inc_not_zero will unconditionally increment
active_counts and then tries to decrement it again on failure.
This patch removes the broken, redundant code.
Signed-off-by: Deng-Cheng Zhu <dczhu@mips.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: David Daney <david.daney@cavium.com>
Cc: Eyal Barzilay <eyal@mips.com>
Cc: Zenon Fortuna <zenon@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/3106/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/kernel')
-rw-r--r-- | arch/mips/kernel/perf_event_mipsxx.c | 5 |
1 files changed, 0 insertions, 5 deletions
diff --git a/arch/mips/kernel/perf_event_mipsxx.c b/arch/mips/kernel/perf_event_mipsxx.c index ab4c761..b5d6b3f 100644 --- a/arch/mips/kernel/perf_event_mipsxx.c +++ b/arch/mips/kernel/perf_event_mipsxx.c @@ -621,11 +621,6 @@ static int mipspmu_event_init(struct perf_event *event) return -ENODEV; if (!atomic_inc_not_zero(&active_events)) { - if (atomic_read(&active_events) > MIPS_MAX_HWEVENTS) { - atomic_dec(&active_events); - return -ENOSPC; - } - mutex_lock(&pmu_reserve_mutex); if (atomic_read(&active_events) == 0) err = mipspmu_get_irq(); |