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perf expr: Make the evaluation of & and | logical and lazy

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Currently the & and | operators are only used in metric thresholds like
(from the tma_retiring metric):

tma_retiring > 0.7 | tma_heavy_operations > 0.1

Thresholds are always computed when present, but a lack of events may
mean the threshold can't be computed. This happens with the option
--metric-no-threshold for say the metric tma_retiring on Tigerlake model
CPUs.

To fully compute the threshold tma_heavy_operations is needed and it
needs the extra events of IDQ.MS_UOPS, UOPS_DECODED.DEC0,
cpu/UOPS_DECODED.DEC0,cmask=1/ and IDQ.MITE_UOPS. So
--metric-no-threshold is a useful option to reduce the number of events
needed and potentially multiplexing of events.

Rather than just fail threshold computations like this, we may know a
result from just the left or right-hand side. So, for tma_retiring if
its value is "> 0.7" we know it is over the threshold. This allows the
metric to have the threshold coloring, when possible, without all the
counters being programmed.

Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Kan Liang <kan.liang@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ahmad Yasin <ahmad.yasin@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Caleb Biggers <caleb.biggers@intel.com>
Cc: Eduard Zingerman <eddyz87@gmail.com>
Cc: Edward Baker <edward.baker@intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Perry Taylor <perry.taylor@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Samantha Alt <samantha.alt@intel.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Weilin Wang <weilin.wang@intel.com>
Link: https://lore.kernel.org/r/20230519063719.1029596-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Ian Rogers 2023-05-18 23:37:18 -07:00 committed by Arnaldo Carvalho de Melo
parent 269f49f9cb
commit 6f765bbbfb
2 changed files with 109 additions and 17 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

40
tools/perf/tests/expr.c
View file

@ -185,6 +185,46 @@ static int test__expr(struct test_suite *t __maybe_unused, int subtest __maybe_u
NULL, ctx) == 0);
TEST_ASSERT_VAL("find ids", hashmap__size(ctx->ids) == 0);
/* The expression is a constant 0.0 without needing to evaluate EVENT1. */
expr__ctx_clear(ctx);
TEST_ASSERT_VAL("find ids",
expr__find_ids("0 & EVENT1 > 0", NULL, ctx) == 0);
TEST_ASSERT_VAL("find ids", hashmap__size(ctx->ids) == 0);
expr__ctx_clear(ctx);
TEST_ASSERT_VAL("find ids",
expr__find_ids("EVENT1 > 0 & 0", NULL, ctx) == 0);
TEST_ASSERT_VAL("find ids", hashmap__size(ctx->ids) == 0);
expr__ctx_clear(ctx);
TEST_ASSERT_VAL("find ids",
expr__find_ids("1 & EVENT1 > 0", NULL, ctx) == 0);
TEST_ASSERT_VAL("find ids", hashmap__size(ctx->ids) == 1);
TEST_ASSERT_VAL("find ids", hashmap__find(ctx->ids, "EVENT1", &val_ptr));
expr__ctx_clear(ctx);
TEST_ASSERT_VAL("find ids",
expr__find_ids("EVENT1 > 0 & 1", NULL, ctx) == 0);
TEST_ASSERT_VAL("find ids", hashmap__size(ctx->ids) == 1);
TEST_ASSERT_VAL("find ids", hashmap__find(ctx->ids, "EVENT1", &val_ptr));
/* The expression is a constant 1.0 without needing to evaluate EVENT1. */
expr__ctx_clear(ctx);
TEST_ASSERT_VAL("find ids",
expr__find_ids("1 | EVENT1 > 0", NULL, ctx) == 0);
TEST_ASSERT_VAL("find ids", hashmap__size(ctx->ids) == 0);
expr__ctx_clear(ctx);
TEST_ASSERT_VAL("find ids",
expr__find_ids("EVENT1 > 0 | 1", NULL, ctx) == 0);
TEST_ASSERT_VAL("find ids", hashmap__size(ctx->ids) == 0);
expr__ctx_clear(ctx);
TEST_ASSERT_VAL("find ids",
expr__find_ids("0 | EVENT1 > 0", NULL, ctx) == 0);
TEST_ASSERT_VAL("find ids", hashmap__size(ctx->ids) == 1);
TEST_ASSERT_VAL("find ids", hashmap__find(ctx->ids, "EVENT1", &val_ptr));
expr__ctx_clear(ctx);
TEST_ASSERT_VAL("find ids",
expr__find_ids("EVENT1 > 0 | 0", NULL, ctx) == 0);
TEST_ASSERT_VAL("find ids", hashmap__size(ctx->ids) == 1);
TEST_ASSERT_VAL("find ids", hashmap__find(ctx->ids, "EVENT1", &val_ptr));
/* Test toplogy constants appear well ordered. */
expr__ctx_clear(ctx);
TEST_ASSERT_VAL("#num_cpus", expr__parse(&num_cpus, ctx, "#num_cpus") == 0);

86
tools/perf/util/expr.y
View file

@ -123,20 +123,6 @@ static struct ids handle_id(struct expr_parse_ctx *ctx, char *id,
* constant value using OP. Its invariant that there are no ids. If computing
* ids for non-constants union the set of IDs that must be computed.
*/
#define BINARY_LONG_OP(RESULT, OP, LHS, RHS) \
if (!compute_ids || (is_const(LHS.val) && is_const(RHS.val))) { \
assert(LHS.ids == NULL); \
assert(RHS.ids == NULL); \
if (isnan(LHS.val) || isnan(RHS.val)) { \
RESULT.val = NAN; \
} else { \
RESULT.val = (long)LHS.val OP (long)RHS.val; \
} \
RESULT.ids = NULL; \
} else { \
RESULT = union_expr(LHS, RHS); \
}
#define BINARY_OP(RESULT, OP, LHS, RHS) \
if (!compute_ids || (is_const(LHS.val) && is_const(RHS.val))) { \
assert(LHS.ids == NULL); \
@ -213,9 +199,75 @@ expr: NUMBER
}
| ID { $$ = handle_id(ctx, $1, compute_ids, /*source_count=*/false); }
| SOURCE_COUNT '(' ID ')' { $$ = handle_id(ctx, $3, compute_ids, /*source_count=*/true); }
| expr '|' expr { BINARY_LONG_OP($$, |, $1, $3); }
| expr '&' expr { BINARY_LONG_OP($$, &, $1, $3); }
| expr '^' expr { BINARY_LONG_OP($$, ^, $1, $3); }
| expr '|' expr
{
if (is_const($1.val) && is_const($3.val)) {
assert($1.ids == NULL);
assert($3.ids == NULL);
$$.ids = NULL;
$$.val = (fpclassify($1.val) == FP_ZERO && fpclassify($3.val) == FP_ZERO) ? 0 : 1;
} else if (is_const($1.val)) {
assert($1.ids == NULL);
if (fpclassify($1.val) == FP_ZERO) {
$$ = $3;
} else {
$$.val = 1;
$$.ids = NULL;
ids__free($3.ids);
}
} else if (is_const($3.val)) {
assert($3.ids == NULL);
if (fpclassify($3.val) == FP_ZERO) {
$$ = $1;
} else {
$$.val = 1;
$$.ids = NULL;
ids__free($1.ids);
}
} else {
$$ = union_expr($1, $3);
}
}
| expr '&' expr
{
if (is_const($1.val) && is_const($3.val)) {
assert($1.ids == NULL);
assert($3.ids == NULL);
$$.val = (fpclassify($1.val) != FP_ZERO && fpclassify($3.val) != FP_ZERO) ? 1 : 0;
$$.ids = NULL;
} else if (is_const($1.val)) {
assert($1.ids == NULL);
if (fpclassify($1.val) != FP_ZERO) {
$$ = $3;
} else {
$$.val = 0;
$$.ids = NULL;
ids__free($3.ids);
}
} else if (is_const($3.val)) {
assert($3.ids == NULL);
if (fpclassify($3.val) != FP_ZERO) {
$$ = $1;
} else {
$$.val = 0;
$$.ids = NULL;
ids__free($1.ids);
}
} else {
$$ = union_expr($1, $3);
}
}
| expr '^' expr
{
if (is_const($1.val) && is_const($3.val)) {
assert($1.ids == NULL);
assert($3.ids == NULL);
$$.val = (fpclassify($1.val) == FP_ZERO) != (fpclassify($3.val) == FP_ZERO) ? 1 : 0;
$$.ids = NULL;
} else {
$$ = union_expr($1, $3);
}
}
| expr '<' expr { BINARY_OP($$, <, $1, $3); }
| expr '>' expr { BINARY_OP($$, >, $1, $3); }
| expr '+' expr { BINARY_OP($$, +, $1, $3); }