From 6f765bbbfb3c8c5993796402a3cba311e9506eed Mon Sep 17 00:00:00 2001 From: Ian Rogers Date: Thu, 18 May 2023 23:37:18 -0700 Subject: [PATCH] perf expr: Make the evaluation of & and | logical and lazy 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 Signed-off-by: Ian Rogers Tested-by: Kan Liang Acked-by: Jiri Olsa Cc: Adrian Hunter Cc: Ahmad Yasin Cc: Alexander Shishkin Cc: Andi Kleen Cc: Andrii Nakryiko Cc: Caleb Biggers Cc: Eduard Zingerman Cc: Edward Baker Cc: Ingo Molnar Cc: James Clark Cc: Mark Rutland Cc: Namhyung Kim Cc: Perry Taylor Cc: Peter Zijlstra Cc: Samantha Alt Cc: Stephane Eranian Cc: Weilin Wang Link: https://lore.kernel.org/r/20230519063719.1029596-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/tests/expr.c | 40 +++++++++++++++++++ tools/perf/util/expr.y | 86 +++++++++++++++++++++++++++++++++-------- 2 files changed, 109 insertions(+), 17 deletions(-) diff --git a/tools/perf/tests/expr.c b/tools/perf/tests/expr.c index 733ead151c63..3d01eb5e2512 100644 --- a/tools/perf/tests/expr.c +++ b/tools/perf/tests/expr.c @@ -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); diff --git a/tools/perf/util/expr.y b/tools/perf/util/expr.y index 4ce931cccb63..f04963eb6be0 100644 --- a/tools/perf/util/expr.y +++ b/tools/perf/util/expr.y @@ -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); }