OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

perf script: Enable printing of branch stack 

This patch improves perf script by enabling printing of the
branch stack via the 'brstack' and 'brstacksym' arguments to
the field selection option -F. The option is off by default
and operates only if the perf.data file has branch stack content.

The branches are printed in to/from pairs. The most recent branch
is printed first. The number of branch entries vary based on the
underlying hardware and filtering used.

The brstack prints FROM/TO addresses in raw hexadecimal format.
The brstacksym prints FROM/TO addresses in symbolic form wherever
possible.

 $ perf script -F ip,brstack
  5d3000 0x401aa0/0x5d2000/M/-/-/-/0 ...

 $ perf script -F ip,brstacksym
  4011e0 noploop+0x0/noploop+0x0/P/-/-/0

The notation F/T/M/X/A/C describes the attributes of the branch.
F=from, T=to, M/P=misprediction/prediction, X=TSX, A=TSX abort, C=cycles (SKL)

Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yuanfang Chen <cyfmxc@gmail.com>
Link: http://lkml.kernel.org/r/1441039273-16260-5-git-send-email-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Stephane Eranian 2015-08-31 18:41:13 +02:00 committed by Arnaldo Carvalho de Melo
parent 729a78417a
commit dc323ce8e7
2 changed files with 93 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
tools/perf/Documentation/perf-script.txt
View File

@ -112,11 +112,11 @@ OPTIONS
--debug-mode::
Do various checks like samples ordering and lost events.
-f::
-F::
--fields::
Comma separated list of fields to print. Options are:
comm, tid, pid, time, cpu, event, trace, ip, sym, dso, addr, symoff,
srcline, period, iregs, flags.
srcline, period, iregs, brstack, brstacksym, flags.
Field list can be prepended with the type, trace, sw or hw,
to indicate to which event type the field list applies.
e.g., -f sw:comm,tid,time,ip,sym and -f trace:time,cpu,trace
@ -175,6 +175,16 @@ OPTIONS
Finally, a user may not set fields to none for all event types.
i.e., -f "" is not allowed.
The brstack output includes branch related information with raw addresses using the
/v/v/v/v/ syntax in the following order:
FROM: branch source instruction
TO : branch target instruction
M/P/-: M=branch target mispredicted or branch direction was mispredicted, P=target predicted or direction predicted, -=not supported
X/- : X=branch inside a transactional region, -=not in transaction region or not supported
A/- : A=TSX abort entry, -=not aborted region or not supported
The brstacksym is identical to brstack, except that the FROM and TO addresses are printed in a symbolic form if possible.
-k::
--vmlinux=<file>::
vmlinux pathname

82
tools/perf/builtin-script.c
View File

@ -51,6 +51,8 @@ enum perf_output_field {
PERF_OUTPUT_SRCLINE = 1U << 12,
PERF_OUTPUT_PERIOD = 1U << 13,
PERF_OUTPUT_IREGS = 1U << 14,
PERF_OUTPUT_BRSTACK = 1U << 15,
PERF_OUTPUT_BRSTACKSYM = 1U << 16,
};
struct output_option {
@ -72,6 +74,8 @@ struct output_option {
{.str = "srcline", .field = PERF_OUTPUT_SRCLINE},
{.str = "period", .field = PERF_OUTPUT_PERIOD},
{.str = "iregs", .field = PERF_OUTPUT_IREGS},
{.str = "brstack", .field = PERF_OUTPUT_BRSTACK},
{.str = "brstacksym", .field = PERF_OUTPUT_BRSTACKSYM},
};
/* default set to maintain compatibility with current format */
@ -425,6 +429,77 @@ static void print_sample_start(struct perf_sample *sample,
}
}
static inline char
mispred_str(struct branch_entry *br)
{
if (!(br->flags.mispred || br->flags.predicted))
return '-';
return br->flags.predicted ? 'P' : 'M';
}
static void print_sample_brstack(union perf_event *event __maybe_unused,
struct perf_sample *sample,
struct thread *thread __maybe_unused,
struct perf_event_attr *attr __maybe_unused)
{
struct branch_stack *br = sample->branch_stack;
u64 i;
if (!(br && br->nr))
return;
for (i = 0; i < br->nr; i++) {
printf(" 0x%"PRIx64"/0x%"PRIx64"/%c/%c/%c/%d ",
br->entries[i].from,
br->entries[i].to,
mispred_str( br->entries + i),
br->entries[i].flags.in_tx? 'X' : '-',
br->entries[i].flags.abort? 'A' : '-',
br->entries[i].flags.cycles);
}
}
static void print_sample_brstacksym(union perf_event *event __maybe_unused,
struct perf_sample *sample,
struct thread *thread __maybe_unused,
struct perf_event_attr *attr __maybe_unused)
{
struct branch_stack *br = sample->branch_stack;
struct addr_location alf, alt;
u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
u64 i, from, to;
if (!(br && br->nr))
return;
for (i = 0; i < br->nr; i++) {
memset(&alf, 0, sizeof(alf));
memset(&alt, 0, sizeof(alt));
from = br->entries[i].from;
to = br->entries[i].to;
thread__find_addr_map(thread, cpumode, MAP__FUNCTION, from, &alf);
if (alf.map)
alf.sym = map__find_symbol(alf.map, alf.addr, NULL);
thread__find_addr_map(thread, cpumode, MAP__FUNCTION, to, &alt);
if (alt.map)
alt.sym = map__find_symbol(alt.map, alt.addr, NULL);
symbol__fprintf_symname_offs(alf.sym, &alf, stdout);
putchar('/');
symbol__fprintf_symname_offs(alt.sym, &alt, stdout);
printf("/%c/%c/%c/%d ",
mispred_str( br->entries + i),
br->entries[i].flags.in_tx? 'X' : '-',
br->entries[i].flags.abort? 'A' : '-',
br->entries[i].flags.cycles);
}
}
static void print_sample_addr(union perf_event *event,
struct perf_sample *sample,
struct thread *thread,
@ -560,6 +635,11 @@ static void process_event(union perf_event *event, struct perf_sample *sample,
if (PRINT_FIELD(IREGS))
print_sample_iregs(event, sample, thread, attr);
if (PRINT_FIELD(BRSTACK))
print_sample_brstack(event, sample, thread, attr);
else if (PRINT_FIELD(BRSTACKSYM))
print_sample_brstacksym(event, sample, thread, attr);
printf("\n");
}
@ -1681,7 +1761,7 @@ int cmd_script(int argc, const char **argv, const char *prefix __maybe_unused)
"comma separated output fields prepend with 'type:'. "
"Valid types: hw,sw,trace,raw. "
"Fields: comm,tid,pid,time,cpu,event,trace,ip,sym,dso,"
"addr,symoff,period,iregs,flags", parse_output_fields),
"addr,symoff,period,iregs,brstack,brstacksym,flags", parse_output_fields),
OPT_BOOLEAN('a', "all-cpus", &system_wide,
"system-wide collection from all CPUs"),
OPT_STRING('S', "symbols", &symbol_conf.sym_list_str, "symbol[,symbol...]",