linux: respect TRACY_NO_SAMPLING for sys-tracing

This compile-time flag was being ignored on Linux. This change adds
gating for software-sampled stack trace sampling following the same
pattern as other `TRACY_NO_SAMPLE_*` options.

If `TRACY_NO_SAMPLING=1` is provided as an environment variable,
software stack sampling is also disabled.
This commit is contained in:
Cody Tapscott 2023-04-04 15:20:46 -04:00
parent 2b7b79352b
commit 6249999153

View File

@ -770,6 +770,13 @@ bool SysTraceStart( int64_t& samplingPeriod )
TracyDebug( "sched_wakeup id: %i\n", wakeupId );
TracyDebug( "drm_vblank_event id: %i\n", vsyncId );
#ifdef TRACY_NO_SAMPLING
const bool noSoftwareSampling = true;
#else
const char* noSoftwareSamplingEnv = GetEnvVar( "TRACY_NO_SAMPLING" );
const bool noSoftwareSampling = noSoftwareSamplingEnv && noSoftwareSamplingEnv[0] == '1';
#endif
#ifdef TRACY_NO_SAMPLE_RETIREMENT
const bool noRetirement = true;
#else
@ -839,28 +846,31 @@ bool SysTraceStart( int64_t& samplingPeriod )
pe.clockid = CLOCK_MONOTONIC_RAW;
#endif
TracyDebug( "Setup software sampling\n" );
ProbePreciseIp( pe, currentPid );
for( int i=0; i<s_numCpus; i++ )
if( !noSoftwareSampling )
{
int fd = perf_event_open( &pe, currentPid, i, -1, PERF_FLAG_FD_CLOEXEC );
if( fd == -1 )
TracyDebug( "Setup software sampling\n" );
ProbePreciseIp( pe, currentPid );
for( int i=0; i<s_numCpus; i++ )
{
pe.exclude_kernel = 1;
ProbePreciseIp( pe, currentPid );
fd = perf_event_open( &pe, currentPid, i, -1, PERF_FLAG_FD_CLOEXEC );
int fd = perf_event_open( &pe, currentPid, i, -1, PERF_FLAG_FD_CLOEXEC );
if( fd == -1 )
{
TracyDebug( " Failed to setup!\n");
break;
pe.exclude_kernel = 1;
ProbePreciseIp( pe, currentPid );
fd = perf_event_open( &pe, currentPid, i, -1, PERF_FLAG_FD_CLOEXEC );
if( fd == -1 )
{
TracyDebug( " Failed to setup!\n");
break;
}
TracyDebug( " No access to kernel samples\n" );
}
new( s_ring+s_numBuffers ) RingBuffer( 64*1024, fd, EventCallstack );
if( s_ring[s_numBuffers].IsValid() )
{
s_numBuffers++;
TracyDebug( " Core %i ok\n", i );
}
TracyDebug( " No access to kernel samples\n" );
}
new( s_ring+s_numBuffers ) RingBuffer( 64*1024, fd, EventCallstack );
if( s_ring[s_numBuffers].IsValid() )
{
s_numBuffers++;
TracyDebug( " Core %i ok\n", i );
}
}