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| author | David S. Miller <davem@davemloft.net> | 2010-12-26 22:37:05 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2010-12-26 22:37:05 -0800 |
| commit | 17f7f4d9fcce8f1b75b5f735569309dee7665968 (patch) | |
| tree | 14d7e49ca0053a0fcab3c33b5023bf3f90c5c08a /arch/x86/kernel/cpu/perf_event.c | |
| parent | 041110a439e21cd40709ead4ffbfa8034619ad77 (diff) | |
| parent | d7c1255a3a21e98bdc64df8ccf005a174d7e6289 (diff) | |
| download | op-kernel-dev-17f7f4d9fcce8f1b75b5f735569309dee7665968.zip op-kernel-dev-17f7f4d9fcce8f1b75b5f735569309dee7665968.tar.gz | |
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
net/ipv4/fib_frontend.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 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) |
