diff options
author | Takashi Iwai <tiwai@suse.de> | 2016-05-16 15:59:00 +0300 |
---|---|---|
committer | Takashi Iwai <tiwai@suse.de> | 2016-05-16 15:59:00 +0300 |
commit | a158f2b79ff1948c864a38296ea4249f7296362b (patch) | |
tree | e62d50376d29a63814cf9d26cbd4c522f6f9271a /arch/x86/events/intel/pt.c | |
parent | 581abbaa03367f0b1327521f30bd2b69b8075b2f (diff) | |
parent | 515511a7920c69aebf7f5fef0cb8e1df6767f34c (diff) | |
download | linux-a158f2b79ff1948c864a38296ea4249f7296362b.tar.xz |
Merge tag 'asoc-v4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Updates for v4.7
The updates this time around are almost all driver code:
- Further slow progress on the topology code.
- Substantial updates and improvements for the da7219, es8328, fsl-ssi
Intel and rcar drivers.
Diffstat (limited to 'arch/x86/events/intel/pt.c')
-rw-r--r-- | arch/x86/events/intel/pt.c | 75 |
1 files changed, 64 insertions, 11 deletions
diff --git a/arch/x86/events/intel/pt.c b/arch/x86/events/intel/pt.c index 6af7cf71d6b2..09a77dbc73c9 100644 --- a/arch/x86/events/intel/pt.c +++ b/arch/x86/events/intel/pt.c @@ -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); + + /* may be already stopped by a PMI */ + if (!(ctl & RTIT_CTL_TRACEEN)) + return; - rdmsrl(MSR_IA32_RTIT_CTL, ctl); - if (start) - ctl |= RTIT_CTL_TRACEEN; - else - ctl &= ~RTIT_CTL_TRACEEN; + 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, @@ -942,11 +956,17 @@ 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; @@ -983,6 +1003,35 @@ 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 */ @@ -992,6 +1041,9 @@ static void pt_event_start(struct perf_event *event, int mode) struct pt *pt = this_cpu_ptr(&pt_ctx); struct pt_buffer *buf = perf_get_aux(&pt->handle); + if (READ_ONCE(pt->vmx_on)) + return; + if (!buf || pt_buffer_is_full(buf, pt)) { event->hw.state = PERF_HES_STOPPED; return; @@ -1014,7 +1066,8 @@ 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; |