xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Merge branch 'perf/urgent' into perf/core, to resolve conflict

Browse Source 
Conflicts:
	arch/x86/events/intel/pt.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Ingo Molnar
2016-04-28 10:35:17 +02:00
parent a8944c5bf8 cf3beb7c90
commit 0b20e59cef
7 changed files with 116 additions and 30 deletions
Download Patch File Download Diff File Expand all files Collapse all files

75
arch/x86/events/intel/pt.c
View File

@@ -136,9 +136,21 @@ static int __init pt_pmu_hw_init(void)
struct dev_ext_attribute *de_attrs;
struct attribute **attrs;
size_t size;
u64 reg;
int ret;
long i;
if (boot_cpu_has(X86_FEATURE_VMX)) {
/*
* Intel SDM, 36.5 "Tracing post-VMXON" says that
* "IA32_VMX_MISC[bit 14]" being 1 means PT can trace
* post-VMXON.
*/
rdmsrl(MSR_IA32_VMX_MISC, reg);
if (reg & BIT(14))
pt_pmu.vmx = true;
}
attrs = NULL;
for (i = 0; i < PT_CPUID_LEAVES; i++) {
@@ -269,20 +281,23 @@ static void pt_config(struct perf_event *event)
reg |= (event->attr.config & PT_CONFIG_MASK);
event->hw.config = reg;
wrmsrl(MSR_IA32_RTIT_CTL, reg);
}
static void pt_config_start(bool start)
static void pt_config_stop(struct perf_event *event)
{
u64 ctl;
u64 ctl = READ_ONCE(event->hw.config);
rdmsrl(MSR_IA32_RTIT_CTL, ctl);
if (start)
ctl |= RTIT_CTL_TRACEEN;
else
ctl &= ~RTIT_CTL_TRACEEN;
/* may be already stopped by a PMI */
if (!(ctl & RTIT_CTL_TRACEEN))
return;
ctl &= ~RTIT_CTL_TRACEEN;
wrmsrl(MSR_IA32_RTIT_CTL, ctl);
WRITE_ONCE(event->hw.config, ctl);
/*
* A wrmsr that disables trace generation serializes other PT
* registers and causes all data packets to be written to memory,
@@ -291,8 +306,7 @@ static void pt_config_start(bool start)
* The below WMB, separating data store and aux_head store matches
* the consumer's RMB that separates aux_head load and data load.
*/
if (!start)
wmb();
wmb();
}
static void pt_config_buffer(void *buf, unsigned int topa_idx,
@@ -922,11 +936,17 @@ void intel_pt_interrupt(void)
if (!ACCESS_ONCE(pt->handle_nmi))
return;
pt_config_start(false);
/*
* If VMX is on and PT does not support it, don't touch anything.
*/
if (READ_ONCE(pt->vmx_on))
return;
if (!event)
return;
pt_config_stop(event);
buf = perf_get_aux(&pt->handle);
if (!buf)
return;
@@ -963,6 +983,35 @@ void intel_pt_interrupt(void)
}
}
void intel_pt_handle_vmx(int on)
{
struct pt *pt = this_cpu_ptr(&pt_ctx);
struct perf_event *event;
unsigned long flags;
/* PT plays nice with VMX, do nothing */
if (pt_pmu.vmx)
return;
/*
* VMXON will clear RTIT_CTL.TraceEn; we need to make
* sure to not try to set it while VMX is on. Disable
* interrupts to avoid racing with pmu callbacks;
* concurrent PMI should be handled fine.
*/
local_irq_save(flags);
WRITE_ONCE(pt->vmx_on, on);
if (on) {
/* prevent pt_config_stop() from writing RTIT_CTL */
event = pt->handle.event;
if (event)
event->hw.config = 0;
}
local_irq_restore(flags);
}
EXPORT_SYMBOL_GPL(intel_pt_handle_vmx);
/*
* PMU callbacks
*/
@@ -973,6 +1022,9 @@ static void pt_event_start(struct perf_event *event, int mode)
struct pt *pt = this_cpu_ptr(&pt_ctx);
struct pt_buffer *buf;
if (READ_ONCE(pt->vmx_on))
return;
buf = perf_aux_output_begin(&pt->handle, event);
if (!buf)
goto fail_stop;
@@ -1007,7 +1059,8 @@ static void pt_event_stop(struct perf_event *event, int mode)
* see comment in intel_pt_interrupt().
*/
ACCESS_ONCE(pt->handle_nmi) = 0;
pt_config_start(false);
pt_config_stop(event);
if (event->hw.state == PERF_HES_STOPPED)
return;