mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

perf cs-etm: Update record event to use new Trace ID protocol 

Trace IDs are now dynamically allocated.

Previously used the static association algorithm that is no longer
used. The 'cpu * 2 + seed' was outdated and broken for systems with high
core counts (>46). as it did not scale and was broken for larger
core counts.

Trace ID will now be sent in PERF_RECORD_AUX_OUTPUT_HW_ID record.

Legacy ID algorithm renamed and retained for limited backward
compatibility use.

Reviewed-by: James Clark <james.clark@arm.com>
Signed-off-by: Mike Leach <mike.leach@linaro.org>
Acked-by: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Darren Hart <darren@os.amperecomputing.com>
Cc: Ganapatrao Kulkarni <gankulkarni@os.amperecomputing.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20230331055645.26918-2-mike.leach@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Mike Leach 2023-03-31 06:56:44 +01:00 committed by Arnaldo Carvalho de Melo
parent 0927729555
commit e5fa5b4110
2 changed files with 34 additions and 22 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
tools/include/linux/coresight-pmu.h
View File

@ -10,11 +10,27 @@
#include <linux/bits.h>
#define CORESIGHT_ETM_PMU_NAME "cs_etm"
#define CORESIGHT_ETM_PMU_SEED 0x10
/*
* The legacy Trace ID system based on fixed calculation from the cpu
* number. This has been replaced by drivers using a dynamic allocation
* system - but need to retain the legacy algorithm for backward comparibility
* in certain situations:-
* a) new perf running on older systems that generate the legacy mapping
* b) older tools that may not update at the same time as the kernel.
*/
#define CORESIGHT_LEGACY_CPU_TRACE_ID(cpu) (0x10 + (cpu * 2))
/* CoreSight trace ID is currently the bottom 7 bits of the value */
#define CORESIGHT_TRACE_ID_VAL_MASK GENMASK(6, 0)
/*
* perf record will set the legacy meta data values as unused initially.
* This allows perf report to manage the decoders created when dynamic
* allocation in operation.
*/
#define CORESIGHT_TRACE_ID_UNUSED_FLAG BIT(31)
/*
* Below are the definition of bit offsets for perf option, and works as
* arbitrary values for all ETM versions.
@ -39,15 +55,4 @@
#define ETM4_CFG_BIT_RETSTK 12
#define ETM4_CFG_BIT_VMID_OPT 15
static inline int coresight_get_trace_id(int cpu)
{
/*
* A trace ID of value 0 is invalid, so let's start at some
* random value that fits in 7 bits and go from there. Since
* the common convention is to have data trace IDs be I(N) + 1,
* set instruction trace IDs as a function of the CPU number.
*/
return (CORESIGHT_ETM_PMU_SEED + (cpu * 2));
}
#endif

27
tools/perf/arch/arm/util/cs-etm.c
View File

@ -437,13 +437,16 @@ static int cs_etm_recording_options(struct auxtrace_record *itr,
evlist__to_front(evlist, cs_etm_evsel);
/*
* In the case of per-cpu mmaps, we need the CPU on the
* AUX event. We also need the contextID in order to be notified
* get the CPU on the sample - need it to associate trace ID in the
* AUX_OUTPUT_HW_ID event, and the AUX event for per-cpu mmaps.
*/
evsel__set_sample_bit(cs_etm_evsel, CPU);
/*
* Also the case of per-cpu mmaps, need the contextID in order to be notified
* when a context switch happened.
*/
if (!perf_cpu_map__empty(cpus)) {
evsel__set_sample_bit(cs_etm_evsel, CPU);
err = cs_etm_set_option(itr, cs_etm_evsel,
BIT(ETM_OPT_CTXTID) | BIT(ETM_OPT_TS));
if (err)
@ -679,8 +682,10 @@ static void cs_etm_save_etmv4_header(__u64 data[], struct auxtrace_record *itr,
/* Get trace configuration register */
data[CS_ETMV4_TRCCONFIGR] = cs_etmv4_get_config(itr);
/* Get traceID from the framework */
data[CS_ETMV4_TRCTRACEIDR] = coresight_get_trace_id(cpu);
/* traceID set to legacy version, in case new perf running on older system */
data[CS_ETMV4_TRCTRACEIDR] =
CORESIGHT_LEGACY_CPU_TRACE_ID(cpu) | CORESIGHT_TRACE_ID_UNUSED_FLAG;
/* Get read-only information from sysFS */
data[CS_ETMV4_TRCIDR0] = cs_etm_get_ro(cs_etm_pmu, cpu,
metadata_etmv4_ro[CS_ETMV4_TRCIDR0]);
@ -711,8 +716,10 @@ static void cs_etm_save_ete_header(__u64 data[], struct auxtrace_record *itr, in
/* Get trace configuration register */
data[CS_ETE_TRCCONFIGR] = cs_etmv4_get_config(itr);
/* Get traceID from the framework */
data[CS_ETE_TRCTRACEIDR] = coresight_get_trace_id(cpu);
/* traceID set to legacy version, in case new perf running on older system */
data[CS_ETE_TRCTRACEIDR] =
CORESIGHT_LEGACY_CPU_TRACE_ID(cpu) | CORESIGHT_TRACE_ID_UNUSED_FLAG;
/* Get read-only information from sysFS */
data[CS_ETE_TRCIDR0] = cs_etm_get_ro(cs_etm_pmu, cpu,
metadata_ete_ro[CS_ETE_TRCIDR0]);
@ -768,9 +775,9 @@ static void cs_etm_get_metadata(int cpu, u32 *offset,
magic = __perf_cs_etmv3_magic;
/* Get configuration register */
info->priv[*offset + CS_ETM_ETMCR] = cs_etm_get_config(itr);
/* Get traceID from the framework */
/* traceID set to legacy value in case new perf running on old system */
info->priv[*offset + CS_ETM_ETMTRACEIDR] =
coresight_get_trace_id(cpu);
CORESIGHT_LEGACY_CPU_TRACE_ID(cpu) | CORESIGHT_TRACE_ID_UNUSED_FLAG;
/* Get read-only information from sysFS */
info->priv[*offset + CS_ETM_ETMCCER] =
cs_etm_get_ro(cs_etm_pmu, cpu,