diff options
| author | Kan Liang <kan.liang@intel.com> | 2015-09-14 14:14:07 (GMT) |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-09-18 07:24:57 (GMT) |
| commit | 96f3eda67fcf2598e9d2794398e0e7ab35138ea6 (patch) | |
| tree | a36a6b964707b54a1bf0f1802b9789a53d63c5d2 | |
| parent | 02386c356af0ce5bbee11ed9b23c312ca60298f0 (diff) | |
| download | linux-96f3eda67fcf2598e9d2794398e0e7ab35138ea6.tar.xz | |
perf/x86/intel: Fix static checker warning in lbr enable
Commit deb27519bf1f ("perf/x86/intel: Fix LBR callstack issue caused
by FREEZE_LBRS_ON_PMI") leads to the following Smatch complaint:
warn: variable dereferenced before check 'cpuc->lbr_sel' (see line 154)
Fix the warning.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: deb27519bf1f ("perf/x86/intel: Fix LBR callstack issue caused by FREEZE_LBRS_ON_PMI")
Link: http://lkml.kernel.org/r/1442240047-48149-1-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
| -rw-r--r-- | arch/x86/kernel/cpu/perf_event_intel_lbr.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/arch/x86/kernel/cpu/perf_event_intel_lbr.c b/arch/x86/kernel/cpu/perf_event_intel_lbr.c index a1d07c7..ad0b8b0 100644 --- a/arch/x86/kernel/cpu/perf_event_intel_lbr.c +++ b/arch/x86/kernel/cpu/perf_event_intel_lbr.c @@ -151,8 +151,9 @@ static void __intel_pmu_lbr_enable(bool pmi) * No need to reprogram LBR_SELECT in a PMI, as it * did not change. */ - lbr_select = cpuc->lbr_sel->config; - if (cpuc->lbr_sel && !pmi) + if (cpuc->lbr_sel) + lbr_select = cpuc->lbr_sel->config; + if (!pmi) wrmsrl(MSR_LBR_SELECT, lbr_select); rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctl); |