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authorLinus Torvalds <torvalds@linux-foundation.org>2011-01-06 10:17:26 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2011-01-06 10:17:26 -0800
commit28d9bfc37c861aa9c8386dff1ac7e9a10e5c5162 (patch)
tree85bcc2db18ff20e380a40aba375e70d14c2671b4 /arch/x86/kernel/cpu/perf_event.c
parentf3b0cfa9b017a9d4686c9b14b908a1685f97a077 (diff)
parent4b95f135f606c87e4056b6d7fd3c5781c818858b (diff)
Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (146 commits) tools, perf: Documentation for the power events API perf: Add calls to suspend trace point perf script: Make some lists static perf script: Use the default lost event handler perf session: Warn about errors when processing pipe events too perf tools: Fix perf_event.h header usage perf test: Clarify some error reports in the open syscall test x86, NMI: Add touch_nmi_watchdog to io_check_error delay x86: Avoid calling arch_trigger_all_cpu_backtrace() at the same time x86: Only call smp_processor_id in non-preempt cases perf timechart: Adjust perf timechart to the new power events perf: Clean up power events by introducing new, more generic ones perf: Do not export power_frequency, but power_start event perf test: Add test for counting open syscalls perf evsel: Auto allocate resources needed for some methods perf evsel: Use {cpu,thread}_map to shorten list of parameters perf tools: Refactor all_tids to hold nr and the map perf tools: Refactor cpumap to hold nr and the map perf evsel: Introduce per cpu and per thread open helpers perf evsel: Steal the counter reading routines from stat ...
Diffstat (limited to 'arch/x86/kernel/cpu/perf_event.c')
-rw-r--r--arch/x86/kernel/cpu/perf_event.c74
1 files changed, 52 insertions, 22 deletions
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 6d75b9145b13..0a360d146596 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -330,9 +330,6 @@ static bool reserve_pmc_hardware(void)
{
int i;
- if (nmi_watchdog == NMI_LOCAL_APIC)
- disable_lapic_nmi_watchdog();
-
for (i = 0; i < x86_pmu.num_counters; i++) {
if (!reserve_perfctr_nmi(x86_pmu.perfctr + i))
goto perfctr_fail;
@@ -355,9 +352,6 @@ perfctr_fail:
for (i--; i >= 0; i--)
release_perfctr_nmi(x86_pmu.perfctr + i);
- if (nmi_watchdog == NMI_LOCAL_APIC)
- enable_lapic_nmi_watchdog();
-
return false;
}
@@ -369,9 +363,6 @@ static void release_pmc_hardware(void)
release_perfctr_nmi(x86_pmu.perfctr + i);
release_evntsel_nmi(x86_pmu.eventsel + i);
}
-
- if (nmi_watchdog == NMI_LOCAL_APIC)
- enable_lapic_nmi_watchdog();
}
#else
@@ -384,15 +375,53 @@ static void release_pmc_hardware(void) {}
static bool check_hw_exists(void)
{
u64 val, val_new = 0;
- int ret = 0;
+ int i, reg, ret = 0;
+
+ /*
+ * Check to see if the BIOS enabled any of the counters, if so
+ * complain and bail.
+ */
+ for (i = 0; i < x86_pmu.num_counters; i++) {
+ reg = x86_pmu.eventsel + i;
+ ret = rdmsrl_safe(reg, &val);
+ if (ret)
+ goto msr_fail;
+ if (val & ARCH_PERFMON_EVENTSEL_ENABLE)
+ goto bios_fail;
+ }
+ if (x86_pmu.num_counters_fixed) {
+ reg = MSR_ARCH_PERFMON_FIXED_CTR_CTRL;
+ ret = rdmsrl_safe(reg, &val);
+ if (ret)
+ goto msr_fail;
+ for (i = 0; i < x86_pmu.num_counters_fixed; i++) {
+ if (val & (0x03 << i*4))
+ goto bios_fail;
+ }
+ }
+
+ /*
+ * Now write a value and read it back to see if it matches,
+ * this is needed to detect certain hardware emulators (qemu/kvm)
+ * that don't trap on the MSR access and always return 0s.
+ */
val = 0xabcdUL;
- ret |= checking_wrmsrl(x86_pmu.perfctr, val);
+ ret = checking_wrmsrl(x86_pmu.perfctr, val);
ret |= rdmsrl_safe(x86_pmu.perfctr, &val_new);
if (ret || val != val_new)
- return false;
+ goto msr_fail;
return true;
+
+bios_fail:
+ printk(KERN_CONT "Broken BIOS detected, using software events only.\n");
+ printk(KERN_ERR FW_BUG "the BIOS has corrupted hw-PMU resources (MSR %x is %Lx)\n", reg, val);
+ return false;
+
+msr_fail:
+ printk(KERN_CONT "Broken PMU hardware detected, using software events only.\n");
+ return false;
}
static void reserve_ds_buffers(void);
@@ -451,7 +480,7 @@ static int x86_setup_perfctr(struct perf_event *event)
struct hw_perf_event *hwc = &event->hw;
u64 config;
- if (!hwc->sample_period) {
+ if (!is_sampling_event(event)) {
hwc->sample_period = x86_pmu.max_period;
hwc->last_period = hwc->sample_period;
local64_set(&hwc->period_left, hwc->sample_period);
@@ -1362,7 +1391,7 @@ static void __init pmu_check_apic(void)
pr_info("no hardware sampling interrupt available.\n");
}
-void __init init_hw_perf_events(void)
+int __init init_hw_perf_events(void)
{
struct event_constraint *c;
int err;
@@ -1377,20 +1406,18 @@ void __init init_hw_perf_events(void)
err = amd_pmu_init();
break;
default:
- return;
+ return 0;
}
if (err != 0) {
pr_cont("no PMU driver, software events only.\n");
- return;
+ return 0;
}
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;
- }
+ if (!check_hw_exists())
+ return 0;
pr_cont("%s PMU driver.\n", x86_pmu.name);
@@ -1438,9 +1465,12 @@ void __init init_hw_perf_events(void)
pr_info("... fixed-purpose events: %d\n", x86_pmu.num_counters_fixed);
pr_info("... event mask: %016Lx\n", x86_pmu.intel_ctrl);
- perf_pmu_register(&pmu);
+ perf_pmu_register(&pmu, "cpu", PERF_TYPE_RAW);
perf_cpu_notifier(x86_pmu_notifier);
+
+ return 0;
}
+early_initcall(init_hw_perf_events);
static inline void x86_pmu_read(struct perf_event *event)
{
@@ -1686,7 +1716,7 @@ perf_callchain_kernel(struct perf_callchain_entry *entry, struct pt_regs *regs)
perf_callchain_store(entry, regs->ip);
- dump_trace(NULL, regs, NULL, regs->bp, &backtrace_ops, entry);
+ dump_trace(NULL, regs, NULL, &backtrace_ops, entry);
}
#ifdef CONFIG_COMPAT