[RFC V1 10/11] perf: Expand perf_branch_entry.type

From: Anshuman Khandual
Date: Sun Jan 23 2022 - 23:33:01 EST


Current perf_branch_entry.type is a 4 bits field just enough to accommodate
16 generic branch types. This is insufficient to accommodate platforms like
arm64 which has much more branch types. Lets just expands this field into a
6 bits one, which can now hold 64 generic branch types. This also adds more
generic branch types and updates the BRBE driver as required.

Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Cc: linux-perf-users@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
---
drivers/perf/arm_pmu_brbe.c | 7 ++++++-
include/uapi/linux/perf_event.h | 10 ++++++++--
tools/include/uapi/linux/perf_event.h | 10 ++++++++--
tools/perf/util/branch.c | 8 +++++++-
4 files changed, 29 insertions(+), 6 deletions(-)

diff --git a/drivers/perf/arm_pmu_brbe.c b/drivers/perf/arm_pmu_brbe.c
index 8d27ad868359..7cd1208c6c58 100644
--- a/drivers/perf/arm_pmu_brbe.c
+++ b/drivers/perf/arm_pmu_brbe.c
@@ -253,12 +253,17 @@ static int brbe_fetch_perf_type(u64 brbinf)
case BRBINF_TYPE_DEBUG_EXIT:
return PERF_BR_DEBUG_EXIT;
case BRBINF_TYPE_SERROR:
+ return PERF_BR_SERROR;
case BRBINF_TYPE_INST_DEBUG:
+ return PERF_BR_DEBUG_INST;
case BRBINF_TYPE_DATA_DEBUG:
+ return PERF_BR_DEBUG_DATA;
case BRBINF_TYPE_ALGN_FAULT:
+ return PERF_BR_FAULT_ALGN;
case BRBINF_TYPE_INST_FAULT:
+ return PERF_BR_FAULT_INST;
case BRBINF_TYPE_DATA_FAULT:
- return PERF_BR_UNKNOWN;
+ return PERF_BR_FAULT_DATA;
default:
pr_warn("unknown branch type captured\n");
return PERF_BR_UNKNOWN;
diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
index b91d0f575d0c..361fdc6b87a0 100644
--- a/include/uapi/linux/perf_event.h
+++ b/include/uapi/linux/perf_event.h
@@ -256,6 +256,12 @@ enum {
PERF_BR_FIQ = 13, /* fiq */
PERF_BR_DEBUG_HALT = 14, /* debug halt */
PERF_BR_DEBUG_EXIT = 15, /* debug exit */
+ PERF_BR_DEBUG_INST = 16, /* instruciton debug */
+ PERF_BR_DEBUG_DATA = 17, /* data debug */
+ PERF_BR_FAULT_ALGN = 18, /* alignment fault */
+ PERF_BR_FAULT_DATA = 19, /* data fault */
+ PERF_BR_FAULT_INST = 20, /* instruction fault */
+ PERF_BR_SERROR = 21, /* system error */
PERF_BR_MAX,
};

@@ -1370,8 +1376,8 @@ struct perf_branch_entry {
in_tx:1, /* in transaction */
abort:1, /* transaction abort */
cycles:16, /* cycle count to last branch */
- type:4, /* branch type */
- reserved:40;
+ type:6, /* branch type */
+ reserved:38;
};

union perf_sample_weight {
diff --git a/tools/include/uapi/linux/perf_event.h b/tools/include/uapi/linux/perf_event.h
index 1882054e8684..9a82b8aaed93 100644
--- a/tools/include/uapi/linux/perf_event.h
+++ b/tools/include/uapi/linux/perf_event.h
@@ -256,6 +256,12 @@ enum {
PERF_BR_FIQ = 13, /* fiq */
PERF_BR_DEBUG_HALT = 14, /* debug halt */
PERF_BR_DEBUG_EXIT = 15, /* debug exit */
+ PERF_BR_DEBUG_INST = 16, /* instruciton debug */
+ PERF_BR_DEBUG_DATA = 17, /* data debug */
+ PERF_BR_FAULT_ALGN = 18, /* alignment fault */
+ PERF_BR_FAULT_DATA = 19, /* data fault */
+ PERF_BR_FAULT_INST = 20, /* instruction fault */
+ PERF_BR_SERROR = 21, /* system error */
PERF_BR_MAX,
};

@@ -1370,8 +1376,8 @@ struct perf_branch_entry {
in_tx:1, /* in transaction */
abort:1, /* transaction abort */
cycles:16, /* cycle count to last branch */
- type:4, /* branch type */
- reserved:40;
+ type:6, /* branch type */
+ reserved:38;
};

union perf_sample_weight {
diff --git a/tools/perf/util/branch.c b/tools/perf/util/branch.c
index 74e5e67b1779..1e216ea2e2a8 100644
--- a/tools/perf/util/branch.c
+++ b/tools/perf/util/branch.c
@@ -54,7 +54,13 @@ const char *branch_type_name(int type)
"IRQ",
"FIQ",
"DEBUG_HALT",
- "DEBUG_EXIT"
+ "DEBUG_EXIT",
+ "DEBUG_INST",
+ "DEBUG_DATA",
+ "FAULT_ALGN",
+ "FAULT_DATA",
+ "FAULT_INST",
+ "SERROR"
};

if (type >= 0 && type < PERF_BR_MAX)
--
2.25.1