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| author | J. Bruce Fields <bfields@redhat.com> | 2010-12-17 13:29:07 -0500 |
|---|---|---|
| committer | J. Bruce Fields <bfields@redhat.com> | 2010-12-17 13:29:07 -0500 |
| commit | ec66ee3797e5848356cf593c6ec7aabf30a00cf1 (patch) | |
| tree | 7ed5c84cc914644ffa1cd1b6a2b45db53fc224e8 /arch/x86/kernel/cpu/perf_event.c | |
| parent | 1205065764f2eda3216ebe213143f69891ee3460 (diff) | |
| parent | b0c3844d8af6b9f3f18f31e1b0502fbefa2166be (diff) | |
| download | op-kernel-dev-ec66ee3797e5848356cf593c6ec7aabf30a00cf1.zip op-kernel-dev-ec66ee3797e5848356cf593c6ec7aabf30a00cf1.tar.gz | |
Merge commit 'v2.6.37-rc6' into for-2.6.38
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) |
