diff options
| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2011-01-06 22:31:35 +0000 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2011-01-06 22:32:03 +0000 |
| commit | 4ec3eb13634529c0bc7466658d84d0bbe3244aea (patch) | |
| tree | b491daac2ccfc7b8ca88e171a43f66888463568a /arch/x86/kernel/cpu/perf_event.c | |
| parent | 24056f525051a9e186af28904b396320e18bf9a0 (diff) | |
| parent | 15095bb0fe779c0403091bda7adce5fb3bb9ca35 (diff) | |
Merge branch 'smp' into misc
Conflicts:
arch/arm/kernel/entry-armv.S
arch/arm/mm/ioremap.c
Diffstat (limited to 'arch/x86/kernel/cpu/perf_event.c')
| -rw-r--r-- | arch/x86/kernel/cpu/perf_event.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c index ed6310183ef..6d75b9145b1 100644 --- a/arch/x86/kernel/cpu/perf_event.c +++ b/arch/x86/kernel/cpu/perf_event.c @@ -381,6 +381,20 @@ static void release_pmc_hardware(void) {} #endif +static bool check_hw_exists(void) +{ + u64 val, val_new = 0; + int ret = 0; + + val = 0xabcdUL; + ret |= checking_wrmsrl(x86_pmu.perfctr, val); + ret |= rdmsrl_safe(x86_pmu.perfctr, &val_new); + if (ret || val != val_new) + return false; + + return true; +} + static void reserve_ds_buffers(void); static void release_ds_buffers(void); @@ -1372,6 +1386,12 @@ void __init init_hw_perf_events(void) pmu_check_apic(); + /* sanity check that the hardware exists or is emulated */ + if (!check_hw_exists()) { + pr_cont("Broken PMU hardware detected, software events only.\n"); + return; + } + pr_cont("%s PMU driver.\n", x86_pmu.name); if (x86_pmu.quirks) |