redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

perf/x86/intel/pt: Add support for PTWRITE and power event tracing 

The Intel PT facility grew some new functionality:

  * PTWRITE packet carries the payload of the new PTWRITE instruction
    that can be used to instrument Intel PT traces with user-supplied
    data. Packets of this type are only generated if 'ptwrite' capability
    is set and PTWEn bit is set in the event attribute's config. Flow
    update packets (FUP) can be generated on PTWRITE packets if FUPonPTW
    config bit is set. Setting these bits is not allowed if 'ptwrite'
    capability is not set.

  * PWRE, PWRX, MWAIT, EXSTOP packets communicate core power management
    events. These depend on 'power_event_tracing' capability and are
    enabled by setting PwrEvtEn bit in the event attribute.

Extend the driver capabilities and provide the proper sanity checks in the
event validation function.

[ tglx: Massaged changelog ]

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: vince@deater.net
Cc: eranian@google.com
Cc: Adrian Hunter <adrian.hunter@intel.com>
Link: http://lkml.kernel.org/r/20160916134819.1978-1-alexander.shishkin@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
hifive-unleashed-5.1
Alexander Shishkin 2016-09-16 16:48:19 +03:00 committed by Thomas Gleixner
parent cd34cd97b7
commit 8ee83b2ab3
2 changed files with 28 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
arch/x86/events/intel/pt.c
View File

@ -69,6 +69,8 @@ static struct pt_cap_desc {
PT_CAP(psb_cyc, 0, CR_EBX, BIT(1)),
PT_CAP(ip_filtering, 0, CR_EBX, BIT(2)),
PT_CAP(mtc, 0, CR_EBX, BIT(3)),
PT_CAP(ptwrite, 0, CR_EBX, BIT(4)),
PT_CAP(power_event_trace, 0, CR_EBX, BIT(5)),
PT_CAP(topa_output, 0, CR_ECX, BIT(0)),
PT_CAP(topa_multiple_entries, 0, CR_ECX, BIT(1)),
PT_CAP(single_range_output, 0, CR_ECX, BIT(2)),
@ -259,10 +261,16 @@ fail:
#define RTIT_CTL_MTC (RTIT_CTL_MTC_EN | \
RTIT_CTL_MTC_RANGE)
#define RTIT_CTL_PTW (RTIT_CTL_PTW_EN | \
RTIT_CTL_FUP_ON_PTW)
#define PT_CONFIG_MASK (RTIT_CTL_TSC_EN | \
RTIT_CTL_DISRETC | \
RTIT_CTL_CYC_PSB | \
RTIT_CTL_MTC)
RTIT_CTL_MTC | \
RTIT_CTL_PWR_EVT_EN | \
RTIT_CTL_FUP_ON_PTW | \
RTIT_CTL_PTW_EN)
static bool pt_event_valid(struct perf_event *event)
{
@ -311,6 +319,20 @@ static bool pt_event_valid(struct perf_event *event)
return false;
}
if (config & RTIT_CTL_PWR_EVT_EN &&
!pt_cap_get(PT_CAP_power_event_trace))
return false;
if (config & RTIT_CTL_PTW) {
if (!pt_cap_get(PT_CAP_ptwrite))
return false;
/* FUPonPTW without PTW doesn't make sense */
if ((config & RTIT_CTL_FUP_ON_PTW) &&
!(config & RTIT_CTL_PTW_EN))
return false;
}
return true;
}

5
arch/x86/events/intel/pt.h
View File

@ -26,11 +26,14 @@
#define RTIT_CTL_CYCLEACC BIT(1)
#define RTIT_CTL_OS BIT(2)
#define RTIT_CTL_USR BIT(3)
#define RTIT_CTL_PWR_EVT_EN BIT(4)
#define RTIT_CTL_FUP_ON_PTW BIT(5)
#define RTIT_CTL_CR3EN BIT(7)
#define RTIT_CTL_TOPA BIT(8)
#define RTIT_CTL_MTC_EN BIT(9)
#define RTIT_CTL_TSC_EN BIT(10)
#define RTIT_CTL_DISRETC BIT(11)
#define RTIT_CTL_PTW_EN BIT(12)
#define RTIT_CTL_BRANCH_EN BIT(13)
#define RTIT_CTL_MTC_RANGE_OFFSET 14
#define RTIT_CTL_MTC_RANGE (0x0full << RTIT_CTL_MTC_RANGE_OFFSET)
@ -91,6 +94,8 @@ enum pt_capabilities {
PT_CAP_psb_cyc,
PT_CAP_ip_filtering,
PT_CAP_mtc,
PT_CAP_ptwrite,
PT_CAP_power_event_trace,
PT_CAP_topa_output,
PT_CAP_topa_multiple_entries,
PT_CAP_single_range_output,