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perf parse-events: Prefer sysfs/JSON hardware events over legacy

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It was requested that RISC-V be able to add events to the perf tool so
the PMU driver didn't need to map legacy events to config encodings:
https://lore.kernel.org/lkml/20240217005738.3744121-1-atishp@rivosinc.com/

This change makes the priority of events specified without a PMU the
same as those specified with a PMU, namely sysfs and JSON events are
checked first before using the legacy encoding.

The hw_term is made more generic as a hardware_event that encodes a
pair of string and int value, allowing parse_events_multi_pmu_add to
fall back on a known encoding when the sysfs/JSON adding fails for
core events. As this covers PE_VALUE_SYM_HW, that token is removed and
related code simplified.

Signed-off-by: Ian Rogers <irogers@google.com>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Atish Patra <atishp@rivosinc.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Beeman Strong <beeman@rivosinc.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240416061533.921723-10-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Ian Rogers 2024-04-15 23:15:25 -07:00 • committed by Arnaldo Carvalho de Melo
parent 5ccc4edfc2
commit 617824a7f0
4 changed files with 105 additions and 70 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

31
tools/perf/util/parse-events.c
View file

@ -1543,7 +1543,7 @@ static int parse_events_add_pmu(struct parse_events_state *parse_state,
} }
int parse_events_multi_pmu_add(struct parse_events_state *parse_state, int parse_events_multi_pmu_add(struct parse_events_state *parse_state,
const char *event_name, const char *event_name, u64 hw_config,
const struct parse_events_terms *const_parsed_terms, const struct parse_events_terms *const_parsed_terms,
struct list_head **listp, void *loc_) struct list_head **listp, void *loc_)
{ {
@ -1551,8 +1551,8 @@ int parse_events_multi_pmu_add(struct parse_events_state *parse_state,
struct list_head *list = NULL; struct list_head *list = NULL;
struct perf_pmu *pmu = NULL; struct perf_pmu *pmu = NULL;
YYLTYPE *loc = loc_; YYLTYPE *loc = loc_;
int ok = 0; int ok = 0, core_ok = 0;
const char *config; const char *tmp;
struct parse_events_terms parsed_terms; struct parse_events_terms parsed_terms;
*listp = NULL; *listp = NULL;
@ -1565,15 +1565,15 @@ int parse_events_multi_pmu_add(struct parse_events_state *parse_state,
return ret; return ret;
} }
config = strdup(event_name); tmp = strdup(event_name);
if (!config) if (!tmp)
goto out_err; goto out_err;
if (parse_events_term__num(&term, if (parse_events_term__num(&term,
PARSE_EVENTS__TERM_TYPE_USER, PARSE_EVENTS__TERM_TYPE_USER,
config, /*num=*/1, /*novalue=*/true, tmp, /*num=*/1, /*novalue=*/true,
loc, /*loc_val=*/NULL) < 0) { loc, /*loc_val=*/NULL) < 0) {
zfree(&config); zfree(&tmp);
goto out_err; goto out_err;
} }
list_add_tail(&term->list, &parsed_terms.terms); list_add_tail(&term->list, &parsed_terms.terms);
@ -1604,6 +1604,8 @@ int parse_events_multi_pmu_add(struct parse_events_state *parse_state,
pr_debug("%s -> %s/%s/\n", event_name, pmu->name, sb.buf); pr_debug("%s -> %s/%s/\n", event_name, pmu->name, sb.buf);
strbuf_release(&sb); strbuf_release(&sb);
ok++; ok++;
if (pmu->is_core)
core_ok++;
} }
} }
@ -1620,6 +1622,18 @@ int parse_events_multi_pmu_add(struct parse_events_state *parse_state,
} }
} }
if (hw_config != PERF_COUNT_HW_MAX && !core_ok) {
/*
* The event wasn't found on core PMUs but it has a hardware
* config version to try.
*/
if (!parse_events_add_numeric(parse_state, list,
PERF_TYPE_HARDWARE, hw_config,
const_parsed_terms,
/*wildcard=*/true))
ok++;
}
out_err: out_err:
parse_events_terms__exit(&parsed_terms); parse_events_terms__exit(&parsed_terms);
if (ok) if (ok)
@ -1673,7 +1687,8 @@ int parse_events_multi_pmu_add_or_add_pmu(struct parse_events_state *parse_state
/* Failure to add, assume event_or_pmu is an event name. */ /* Failure to add, assume event_or_pmu is an event name. */
zfree(listp); zfree(listp);
if (!parse_events_multi_pmu_add(parse_state, event_or_pmu, const_parsed_terms, listp, loc)) if (!parse_events_multi_pmu_add(parse_state, event_or_pmu, PERF_COUNT_HW_MAX,
const_parsed_terms, listp, loc))
return 0; return 0;
if (asprintf(&help, "Unable to find PMU or event on a PMU of '%s'", event_or_pmu) < 0) if (asprintf(&help, "Unable to find PMU or event on a PMU of '%s'", event_or_pmu) < 0)

2
tools/perf/util/parse-events.h
View file

@ -215,7 +215,7 @@ struct evsel *parse_events__add_event(int idx, struct perf_event_attr *attr,
struct perf_pmu *pmu); struct perf_pmu *pmu);
int parse_events_multi_pmu_add(struct parse_events_state *parse_state, int parse_events_multi_pmu_add(struct parse_events_state *parse_state,
const char *event_name, const char *event_name, u64 hw_config,
const struct parse_events_terms *const_parsed_terms, const struct parse_events_terms *const_parsed_terms,
struct list_head **listp, void *loc); struct list_head **listp, void *loc);

76
tools/perf/util/parse-events.l
View file

@ -100,12 +100,12 @@ do { \
yyless(0); \ yyless(0); \
} while (0) } while (0)
static int sym(yyscan_t scanner, int type, int config) static int sym(yyscan_t scanner, int config)
{ {
YYSTYPE *yylval = parse_events_get_lval(scanner); YYSTYPE *yylval = parse_events_get_lval(scanner);
yylval->num = (type << 16) + config; yylval->num = config;
return type == PERF_TYPE_HARDWARE ? PE_VALUE_SYM_HW : PE_VALUE_SYM_SW; return PE_VALUE_SYM_SW;
} }
static int tool(yyscan_t scanner, enum perf_tool_event event) static int tool(yyscan_t scanner, enum perf_tool_event event)
@ -124,13 +124,13 @@ static int term(yyscan_t scanner, enum parse_events__term_type type)
return PE_TERM; return PE_TERM;
} }
static int hw_term(yyscan_t scanner, int config) static int hw(yyscan_t scanner, int config)
{ {
YYSTYPE *yylval = parse_events_get_lval(scanner); YYSTYPE *yylval = parse_events_get_lval(scanner);
char *text = parse_events_get_text(scanner); char *text = parse_events_get_text(scanner);
yylval->hardware_term.str = strdup(text); yylval->hardware_event.str = strdup(text);
yylval->hardware_term.num = PERF_TYPE_HARDWARE + config; yylval->hardware_event.num = config;
return PE_TERM_HW; return PE_TERM_HW;
} }
@ -246,16 +246,16 @@ percore { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_PERCORE); }
aux-output { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_AUX_OUTPUT); } aux-output { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_AUX_OUTPUT); }
aux-sample-size { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_AUX_SAMPLE_SIZE); } aux-sample-size { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_AUX_SAMPLE_SIZE); }
metric-id { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_METRIC_ID); } metric-id { return term(yyscanner, PARSE_EVENTS__TERM_TYPE_METRIC_ID); }
cpu-cycles|cycles { return hw_term(yyscanner, PERF_COUNT_HW_CPU_CYCLES); } cpu-cycles|cycles { return hw(yyscanner, PERF_COUNT_HW_CPU_CYCLES); }
stalled-cycles-frontend|idle-cycles-frontend { return hw_term(yyscanner, PERF_COUNT_HW_STALLED_CYCLES_FRONTEND); } stalled-cycles-frontend|idle-cycles-frontend { return hw(yyscanner, PERF_COUNT_HW_STALLED_CYCLES_FRONTEND); }
stalled-cycles-backend|idle-cycles-backend { return hw_term(yyscanner, PERF_COUNT_HW_STALLED_CYCLES_BACKEND); } stalled-cycles-backend|idle-cycles-backend { return hw(yyscanner, PERF_COUNT_HW_STALLED_CYCLES_BACKEND); }
instructions { return hw_term(yyscanner, PERF_COUNT_HW_INSTRUCTIONS); } instructions { return hw(yyscanner, PERF_COUNT_HW_INSTRUCTIONS); }
cache-references { return hw_term(yyscanner, PERF_COUNT_HW_CACHE_REFERENCES); } cache-references { return hw(yyscanner, PERF_COUNT_HW_CACHE_REFERENCES); }
cache-misses { return hw_term(yyscanner, PERF_COUNT_HW_CACHE_MISSES); } cache-misses { return hw(yyscanner, PERF_COUNT_HW_CACHE_MISSES); }
branch-instructions|branches { return hw_term(yyscanner, PERF_COUNT_HW_BRANCH_INSTRUCTIONS); } branch-instructions|branches { return hw(yyscanner, PERF_COUNT_HW_BRANCH_INSTRUCTIONS); }
branch-misses { return hw_term(yyscanner, PERF_COUNT_HW_BRANCH_MISSES); } branch-misses { return hw(yyscanner, PERF_COUNT_HW_BRANCH_MISSES); }
bus-cycles { return hw_term(yyscanner, PERF_COUNT_HW_BUS_CYCLES); } bus-cycles { return hw(yyscanner, PERF_COUNT_HW_BUS_CYCLES); }
ref-cycles { return hw_term(yyscanner, PERF_COUNT_HW_REF_CPU_CYCLES); } ref-cycles { return hw(yyscanner, PERF_COUNT_HW_REF_CPU_CYCLES); }
r{num_raw_hex} { return str(yyscanner, PE_RAW); } r{num_raw_hex} { return str(yyscanner, PE_RAW); }
r0x{num_raw_hex} { return str(yyscanner, PE_RAW); } r0x{num_raw_hex} { return str(yyscanner, PE_RAW); }
, { return ','; } , { return ','; }
@ -299,31 +299,31 @@ r0x{num_raw_hex} { return str(yyscanner, PE_RAW); }
<<EOF>> { BEGIN(INITIAL); } <<EOF>> { BEGIN(INITIAL); }
} }
cpu-cycles|cycles { return sym(yyscanner, PERF_TYPE_HARDWARE, PERF_COUNT_HW_CPU_CYCLES); } cpu-cycles|cycles { return hw(yyscanner, PERF_COUNT_HW_CPU_CYCLES); }
stalled-cycles-frontend|idle-cycles-frontend { return sym(yyscanner, PERF_TYPE_HARDWARE, PERF_COUNT_HW_STALLED_CYCLES_FRONTEND); } stalled-cycles-frontend|idle-cycles-frontend { return hw(yyscanner, PERF_COUNT_HW_STALLED_CYCLES_FRONTEND); }
stalled-cycles-backend|idle-cycles-backend { return sym(yyscanner, PERF_TYPE_HARDWARE, PERF_COUNT_HW_STALLED_CYCLES_BACKEND); } stalled-cycles-backend|idle-cycles-backend { return hw(yyscanner, PERF_COUNT_HW_STALLED_CYCLES_BACKEND); }
instructions { return sym(yyscanner, PERF_TYPE_HARDWARE, PERF_COUNT_HW_INSTRUCTIONS); } instructions { return hw(yyscanner, PERF_COUNT_HW_INSTRUCTIONS); }
cache-references { return sym(yyscanner, PERF_TYPE_HARDWARE, PERF_COUNT_HW_CACHE_REFERENCES); } cache-references { return hw(yyscanner, PERF_COUNT_HW_CACHE_REFERENCES); }
cache-misses { return sym(yyscanner, PERF_TYPE_HARDWARE, PERF_COUNT_HW_CACHE_MISSES); } cache-misses { return hw(yyscanner, PERF_COUNT_HW_CACHE_MISSES); }
branch-instructions|branches { return sym(yyscanner, PERF_TYPE_HARDWARE, PERF_COUNT_HW_BRANCH_INSTRUCTIONS); } branch-instructions|branches { return hw(yyscanner, PERF_COUNT_HW_BRANCH_INSTRUCTIONS); }
branch-misses { return sym(yyscanner, PERF_TYPE_HARDWARE, PERF_COUNT_HW_BRANCH_MISSES); } branch-misses { return hw(yyscanner, PERF_COUNT_HW_BRANCH_MISSES); }
bus-cycles { return sym(yyscanner, PERF_TYPE_HARDWARE, PERF_COUNT_HW_BUS_CYCLES); } bus-cycles { return hw(yyscanner, PERF_COUNT_HW_BUS_CYCLES); }
ref-cycles { return sym(yyscanner, PERF_TYPE_HARDWARE, PERF_COUNT_HW_REF_CPU_CYCLES); } ref-cycles { return hw(yyscanner, PERF_COUNT_HW_REF_CPU_CYCLES); }
cpu-clock { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_CPU_CLOCK); } cpu-clock { return sym(yyscanner, PERF_COUNT_SW_CPU_CLOCK); }
task-clock { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_TASK_CLOCK); } task-clock { return sym(yyscanner, PERF_COUNT_SW_TASK_CLOCK); }
page-faults|faults { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_PAGE_FAULTS); } page-faults|faults { return sym(yyscanner, PERF_COUNT_SW_PAGE_FAULTS); }
minor-faults { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_PAGE_FAULTS_MIN); } minor-faults { return sym(yyscanner, PERF_COUNT_SW_PAGE_FAULTS_MIN); }
major-faults { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_PAGE_FAULTS_MAJ); } major-faults { return sym(yyscanner, PERF_COUNT_SW_PAGE_FAULTS_MAJ); }
context-switches|cs { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_CONTEXT_SWITCHES); } context-switches|cs { return sym(yyscanner, PERF_COUNT_SW_CONTEXT_SWITCHES); }
cpu-migrations|migrations { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_CPU_MIGRATIONS); } cpu-migrations|migrations { return sym(yyscanner, PERF_COUNT_SW_CPU_MIGRATIONS); }
alignment-faults { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_ALIGNMENT_FAULTS); } alignment-faults { return sym(yyscanner, PERF_COUNT_SW_ALIGNMENT_FAULTS); }
emulation-faults { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_EMULATION_FAULTS); } emulation-faults { return sym(yyscanner, PERF_COUNT_SW_EMULATION_FAULTS); }
dummy { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_DUMMY); } dummy { return sym(yyscanner, PERF_COUNT_SW_DUMMY); }
duration_time { return tool(yyscanner, PERF_TOOL_DURATION_TIME); } duration_time { return tool(yyscanner, PERF_TOOL_DURATION_TIME); }
user_time { return tool(yyscanner, PERF_TOOL_USER_TIME); } user_time { return tool(yyscanner, PERF_TOOL_USER_TIME); }
system_time { return tool(yyscanner, PERF_TOOL_SYSTEM_TIME); } system_time { return tool(yyscanner, PERF_TOOL_SYSTEM_TIME); }
bpf-output { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_BPF_OUTPUT); } bpf-output { return sym(yyscanner, PERF_COUNT_SW_BPF_OUTPUT); }
cgroup-switches { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_CGROUP_SWITCHES); } cgroup-switches { return sym(yyscanner, PERF_COUNT_SW_CGROUP_SWITCHES); }
{lc_type} { return str(yyscanner, PE_LEGACY_CACHE); } {lc_type} { return str(yyscanner, PE_LEGACY_CACHE); }
{lc_type}-{lc_op_result} { return str(yyscanner, PE_LEGACY_CACHE); } {lc_type}-{lc_op_result} { return str(yyscanner, PE_LEGACY_CACHE); }

66
tools/perf/util/parse-events.y
View file

@ -55,7 +55,7 @@ static void free_list_evsel(struct list_head* list_evsel)
%} %}
%token PE_START_EVENTS PE_START_TERMS %token PE_START_EVENTS PE_START_TERMS
%token PE_VALUE PE_VALUE_SYM_HW PE_VALUE_SYM_SW PE_TERM %token PE_VALUE PE_VALUE_SYM_SW PE_TERM
%token PE_VALUE_SYM_TOOL %token PE_VALUE_SYM_TOOL
%token PE_EVENT_NAME %token PE_EVENT_NAME
%token PE_RAW PE_NAME %token PE_RAW PE_NAME
@ -66,11 +66,9 @@ static void free_list_evsel(struct list_head* list_evsel)
%token PE_DRV_CFG_TERM %token PE_DRV_CFG_TERM
%token PE_TERM_HW %token PE_TERM_HW
%type <num> PE_VALUE %type <num> PE_VALUE
%type <num> PE_VALUE_SYM_HW
%type <num> PE_VALUE_SYM_SW %type <num> PE_VALUE_SYM_SW
%type <num> PE_VALUE_SYM_TOOL %type <num> PE_VALUE_SYM_TOOL
%type <term_type> PE_TERM %type <term_type> PE_TERM
%type <num> value_sym
%type <str> PE_RAW %type <str> PE_RAW
%type <str> PE_NAME %type <str> PE_NAME
%type <str> PE_LEGACY_CACHE %type <str> PE_LEGACY_CACHE
@ -87,6 +85,7 @@ static void free_list_evsel(struct list_head* list_evsel)
%type <list_terms> opt_pmu_config %type <list_terms> opt_pmu_config
%destructor { parse_events_terms__delete ($$); } <list_terms> %destructor { parse_events_terms__delete ($$); } <list_terms>
%type <list_evsel> event_pmu %type <list_evsel> event_pmu
%type <list_evsel> event_legacy_hardware
%type <list_evsel> event_legacy_symbol %type <list_evsel> event_legacy_symbol
%type <list_evsel> event_legacy_cache %type <list_evsel> event_legacy_cache
%type <list_evsel> event_legacy_mem %type <list_evsel> event_legacy_mem
@ -104,8 +103,8 @@ static void free_list_evsel(struct list_head* list_evsel)
%destructor { free_list_evsel ($$); } <list_evsel> %destructor { free_list_evsel ($$); } <list_evsel>
%type <tracepoint_name> tracepoint_name %type <tracepoint_name> tracepoint_name
%destructor { free ($$.sys); free ($$.event); } <tracepoint_name> %destructor { free ($$.sys); free ($$.event); } <tracepoint_name>
%type <hardware_term> PE_TERM_HW %type <hardware_event> PE_TERM_HW
%destructor { free ($$.str); } <hardware_term> %destructor { free ($$.str); } <hardware_event>
%union %union
{ {
@ -119,10 +118,10 @@ static void free_list_evsel(struct list_head* list_evsel)
char *sys; char *sys;
char *event; char *event;
} tracepoint_name; } tracepoint_name;
struct hardware_term { struct hardware_event {
char *str; char *str;
u64 num; u64 num;
} hardware_term; } hardware_event;
} }
%% %%
@ -263,6 +262,7 @@ PE_EVENT_NAME event_def
event_def event_def
event_def: event_pmu | event_def: event_pmu |
event_legacy_hardware |
event_legacy_symbol | event_legacy_symbol |
event_legacy_cache sep_dc | event_legacy_cache sep_dc |
event_legacy_mem sep_dc | event_legacy_mem sep_dc |
@ -289,7 +289,7 @@ PE_NAME sep_dc
struct list_head *list; struct list_head *list;
int err; int err;
err = parse_events_multi_pmu_add(_parse_state, $1, NULL, &list, &@1); err = parse_events_multi_pmu_add(_parse_state, $1, PERF_COUNT_HW_MAX, NULL, &list, &@1);
if (err < 0) { if (err < 0) {
struct parse_events_state *parse_state = _parse_state; struct parse_events_state *parse_state = _parse_state;
struct parse_events_error *error = parse_state->error; struct parse_events_error *error = parse_state->error;
@ -305,24 +305,45 @@ PE_NAME sep_dc
$$ = list; $$ = list;
} }
value_sym: event_legacy_hardware:
PE_VALUE_SYM_HW PE_TERM_HW opt_pmu_config
| {
PE_VALUE_SYM_SW /* List of created evsels. */
struct list_head *list = NULL;
int err = parse_events_multi_pmu_add(_parse_state, $1.str, $1.num, $2, &list, &@1);
event_legacy_symbol: free($1.str);
value_sym '/' event_config '/' parse_events_terms__delete($2);
if (err)
PE_ABORT(err);
$$ = list;
}
|
PE_TERM_HW sep_dc
{
struct list_head *list;
int err;
err = parse_events_multi_pmu_add(_parse_state, $1.str, $1.num, NULL, &list, &@1);
free($1.str);
if (err)
PE_ABORT(err);
$$ = list;
}
event_legacy_symbol:
PE_VALUE_SYM_SW '/' event_config '/'
{ {
struct list_head *list; struct list_head *list;
int type = $1 >> 16;
int config = $1 & 255;
int err; int err;
bool wildcard = (type == PERF_TYPE_HARDWARE || type == PERF_TYPE_HW_CACHE);
list = alloc_list(); list = alloc_list();
if (!list) if (!list)
YYNOMEM; YYNOMEM;
err = parse_events_add_numeric(_parse_state, list, type, config, $3, wildcard); err = parse_events_add_numeric(_parse_state, list,
/*type=*/PERF_TYPE_SOFTWARE, /*config=*/$1,
$3, /*wildcard=*/false);
parse_events_terms__delete($3); parse_events_terms__delete($3);
if (err) { if (err) {
free_list_evsel(list); free_list_evsel(list);
@ -331,18 +352,17 @@ value_sym '/' event_config '/'
$$ = list; $$ = list;
} }
| |
value_sym sep_slash_slash_dc PE_VALUE_SYM_SW sep_slash_slash_dc
{ {
struct list_head *list; struct list_head *list;
int type = $1 >> 16;
int config = $1 & 255;
bool wildcard = (type == PERF_TYPE_HARDWARE || type == PERF_TYPE_HW_CACHE);
int err; int err;
list = alloc_list(); list = alloc_list();
if (!list) if (!list)
YYNOMEM; YYNOMEM;
err = parse_events_add_numeric(_parse_state, list, type, config, /*head_config=*/NULL, wildcard); err = parse_events_add_numeric(_parse_state, list,
/*type=*/PERF_TYPE_SOFTWARE, /*config=*/$1,
/*head_config=*/NULL, /*wildcard=*/false);
if (err) if (err)
PE_ABORT(err); PE_ABORT(err);
$$ = list; $$ = list;