[PATCH V2 03/13] perf tools: Support new branch sample type for LBR TOS
From: kan . liang
Date: Mon Oct 21 2019 - 16:04:58 EST
From: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Support new branch sample type for LBR TOS.
Enable LBR_TOS by default in LBR call stack mode.
If kernel doesn't support the sample type, switching it off.
Add a new branch options "tos" for the new branch sample type.
Set tos to -1ULL if the LBR TOS information is unavailable.
Signed-off-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
---
tools/include/uapi/linux/perf_event.h | 10 +++++++++-
tools/perf/util/event.h | 1 +
tools/perf/util/evsel.c | 20 +++++++++++++++++---
tools/perf/util/evsel.h | 6 ++++++
tools/perf/util/parse-branch-options.c | 1 +
tools/perf/util/perf_event_attr_fprintf.c | 1 +
6 files changed, 35 insertions(+), 4 deletions(-)
diff --git a/tools/include/uapi/linux/perf_event.h b/tools/include/uapi/linux/perf_event.h
index bb7b271397a6..b1f022190571 100644
--- a/tools/include/uapi/linux/perf_event.h
+++ b/tools/include/uapi/linux/perf_event.h
@@ -180,6 +180,8 @@ enum perf_branch_sample_type_shift {
PERF_SAMPLE_BRANCH_TYPE_SAVE_SHIFT = 16, /* save branch type */
+ PERF_SAMPLE_BRANCH_LBR_TOS_SHIFT = 17, /* save LBR TOS */
+
PERF_SAMPLE_BRANCH_MAX_SHIFT /* non-ABI */
};
@@ -207,6 +209,8 @@ enum perf_branch_sample_type {
PERF_SAMPLE_BRANCH_TYPE_SAVE =
1U << PERF_SAMPLE_BRANCH_TYPE_SAVE_SHIFT,
+ PERF_SAMPLE_BRANCH_LBR_TOS = 1U << PERF_SAMPLE_BRANCH_LBR_TOS_SHIFT,
+
PERF_SAMPLE_BRANCH_MAX = 1U << PERF_SAMPLE_BRANCH_MAX_SHIFT,
};
@@ -849,7 +853,11 @@ enum perf_event_type {
* char data[size];}&& PERF_SAMPLE_RAW
*
* { u64 nr;
- * { u64 from, to, flags } lbr[nr];} && PERF_SAMPLE_BRANCH_STACK
+ * { u64 from, to, flags } lbr[nr];
+ *
+ * # only available if PERF_SAMPLE_BRANCH_LBR_TOS is set
+ * u64 tos;
+ * } && PERF_SAMPLE_BRANCH_STACK
*
* { u64 abi; # enum perf_sample_regs_abi
* u64 regs[weight(mask)]; } && PERF_SAMPLE_REGS_USER
diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h
index a0a0c91cde4a..98794758546b 100644
--- a/tools/perf/util/event.h
+++ b/tools/perf/util/event.h
@@ -130,6 +130,7 @@ struct perf_sample {
u32 raw_size;
u64 data_src;
u64 phys_addr;
+ u64 lbr_tos;
u32 flags;
u16 insn_len;
u8 cpumode;
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index abc7fda4a0fe..6b91897e4ca2 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -712,7 +712,8 @@ static void __perf_evsel__config_callchain(struct evsel *evsel,
attr->branch_sample_type = PERF_SAMPLE_BRANCH_USER |
PERF_SAMPLE_BRANCH_CALL_STACK |
PERF_SAMPLE_BRANCH_NO_CYCLES |
- PERF_SAMPLE_BRANCH_NO_FLAGS;
+ PERF_SAMPLE_BRANCH_NO_FLAGS |
+ PERF_SAMPLE_BRANCH_LBR_TOS;
}
} else
pr_warning("Cannot use LBR callstack with branch stack. "
@@ -763,7 +764,8 @@ perf_evsel__reset_callgraph(struct evsel *evsel,
if (param->record_mode == CALLCHAIN_LBR) {
perf_evsel__reset_sample_bit(evsel, BRANCH_STACK);
attr->branch_sample_type &= ~(PERF_SAMPLE_BRANCH_USER |
- PERF_SAMPLE_BRANCH_CALL_STACK);
+ PERF_SAMPLE_BRANCH_CALL_STACK |
+ PERF_SAMPLE_BRANCH_LBR_TOS);
}
if (param->record_mode == CALLCHAIN_DWARF) {
perf_evsel__reset_sample_bit(evsel, REGS_USER);
@@ -1641,6 +1643,8 @@ int evsel__open(struct evsel *evsel, struct perf_cpu_map *cpus,
evsel->core.attr.ksymbol = 0;
if (perf_missing_features.bpf)
evsel->core.attr.bpf_event = 0;
+ if (perf_missing_features.lbr_tos)
+ evsel->core.attr.branch_sample_type &= ~PERF_SAMPLE_BRANCH_LBR_TOS;
retry_sample_id:
if (perf_missing_features.sample_id_all)
evsel->core.attr.sample_id_all = 0;
@@ -1752,7 +1756,12 @@ int evsel__open(struct evsel *evsel, struct perf_cpu_map *cpus,
* Must probe features in the order they were added to the
* perf_event_attr interface.
*/
- if (!perf_missing_features.aux_output && evsel->core.attr.aux_output) {
+ if (!perf_missing_features.lbr_tos &&
+ (evsel->core.attr.branch_sample_type & PERF_SAMPLE_BRANCH_LBR_TOS)) {
+ perf_missing_features.lbr_tos = true;
+ pr_debug2("switching off LBR TOS support\n");
+ goto fallback_missing_features;
+ } else if (!perf_missing_features.aux_output && evsel->core.attr.aux_output) {
perf_missing_features.aux_output = true;
pr_debug2("Kernel has no attr.aux_output support, bailing out\n");
goto out_close;
@@ -2126,6 +2135,11 @@ int perf_evsel__parse_sample(struct evsel *evsel, union perf_event *event,
sz = data->branch_stack->nr * sizeof(struct branch_entry);
OVERFLOW_CHECK(array, sz, max_size);
array = (void *)array + sz;
+
+ if (perf_evsel__has_lbr_tos(evsel))
+ data->lbr_tos = *array++;
+ else
+ data->lbr_tos = -1ULL;
}
if (type & PERF_SAMPLE_REGS_USER) {
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index ddc5ee6f6592..52f8a5401361 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -115,6 +115,7 @@ struct perf_missing_features {
bool ksymbol;
bool bpf;
bool aux_output;
+ bool lbr_tos;
};
extern struct perf_missing_features perf_missing_features;
@@ -377,6 +378,11 @@ for ((_evsel) = _leader; \
(_evsel) && (_evsel)->leader == (_leader); \
(_evsel) = list_entry((_evsel)->core.node.next, struct evsel, core.node))
+static inline bool perf_evsel__has_lbr_tos(const struct evsel *evsel)
+{
+ return evsel->core.attr.branch_sample_type & PERF_SAMPLE_BRANCH_LBR_TOS;
+}
+
static inline bool perf_evsel__has_branch_callstack(const struct evsel *evsel)
{
return evsel->core.attr.branch_sample_type & PERF_SAMPLE_BRANCH_CALL_STACK;
diff --git a/tools/perf/util/parse-branch-options.c b/tools/perf/util/parse-branch-options.c
index bb4aa88c50a8..1425c3525f17 100644
--- a/tools/perf/util/parse-branch-options.c
+++ b/tools/perf/util/parse-branch-options.c
@@ -32,6 +32,7 @@ static const struct branch_mode branch_modes[] = {
BRANCH_OPT("call", PERF_SAMPLE_BRANCH_CALL),
BRANCH_OPT("save_type", PERF_SAMPLE_BRANCH_TYPE_SAVE),
BRANCH_OPT("stack", PERF_SAMPLE_BRANCH_CALL_STACK),
+ BRANCH_OPT("tos", PERF_SAMPLE_BRANCH_LBR_TOS),
BRANCH_END
};
diff --git a/tools/perf/util/perf_event_attr_fprintf.c b/tools/perf/util/perf_event_attr_fprintf.c
index d4ad3f04923a..5c4047e7cc8d 100644
--- a/tools/perf/util/perf_event_attr_fprintf.c
+++ b/tools/perf/util/perf_event_attr_fprintf.c
@@ -50,6 +50,7 @@ static void __p_branch_sample_type(char *buf, size_t size, u64 value)
bit_name(ABORT_TX), bit_name(IN_TX), bit_name(NO_TX),
bit_name(COND), bit_name(CALL_STACK), bit_name(IND_JUMP),
bit_name(CALL), bit_name(NO_FLAGS), bit_name(NO_CYCLES),
+ bit_name(LBR_TOS),
{ .name = NULL, }
};
#undef bit_name
--
2.17.1