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| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2010-12-18 14:27:55 (GMT) |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2010-12-18 14:27:55 (GMT) |
| commit | 2f841ed13b9f10037e25ddf417d01700ecd886d0 (patch) | |
| tree | 123448d98b3be03ac90fbb6e32f224235063c8bf /arch/x86/kernel/cpu/perf_event.c | |
| parent | 961ec6daa7b14f376c30d447a830fa4783a2112c (diff) | |
| parent | 8fbf397c3389c1dedfa9ee412715046ab28fd82d (diff) | |
| download | linux-fsl-qoriq-2f841ed13b9f10037e25ddf417d01700ecd886d0.tar.xz | |
Merge branch 'hw-breakpoint' of git://repo.or.cz/linux-2.6/linux-wd into devel-stable
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 ed63101..6d75b91 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) |