diff options
| -rw-r--r-- | tools/perf/tests/expr.c | 24 | ||||
| -rw-r--r-- | tools/perf/util/cputopo.c | 15 | ||||
| -rw-r--r-- | tools/perf/util/cputopo.h | 2 | ||||
| -rw-r--r-- | tools/perf/util/expr.c | 9 | ||||
| -rw-r--r-- | tools/perf/util/smt.c | 95 | ||||
| -rw-r--r-- | tools/perf/util/smt.h | 5 |
6 files changed, 49 insertions, 101 deletions
diff --git a/tools/perf/tests/expr.c b/tools/perf/tests/expr.c index 7ca5e37de560..db736ed49556 100644 --- a/tools/perf/tests/expr.c +++ b/tools/perf/tests/expr.c @@ -1,4 +1,5 @@ // SPDX-License-Identifier: GPL-2.0 +#include "util/cputopo.h" #include "util/debug.h" #include "util/expr.h" #include "util/header.h" @@ -154,15 +155,20 @@ static int test__expr(struct test_suite *t __maybe_unused, int subtest __maybe_u (void **)&val_ptr)); /* Only EVENT1 or EVENT2 need be measured depending on the value of smt_on. */ - expr__ctx_clear(ctx); - TEST_ASSERT_VAL("find ids", - expr__find_ids("EVENT1 if #smt_on else EVENT2", - NULL, ctx) == 0); - TEST_ASSERT_VAL("find ids", hashmap__size(ctx->ids) == 1); - TEST_ASSERT_VAL("find ids", hashmap__find(ctx->ids, - smt_on() ? "EVENT1" : "EVENT2", - (void **)&val_ptr)); - + { + struct cpu_topology *topology = cpu_topology__new(); + bool smton = smt_on(topology); + + cpu_topology__delete(topology); + expr__ctx_clear(ctx); + TEST_ASSERT_VAL("find ids", + expr__find_ids("EVENT1 if #smt_on else EVENT2", + NULL, ctx) == 0); + TEST_ASSERT_VAL("find ids", hashmap__size(ctx->ids) == 1); + TEST_ASSERT_VAL("find ids", hashmap__find(ctx->ids, + smton ? "EVENT1" : "EVENT2", + (void **)&val_ptr)); + } /* The expression is a constant 1.0 without needing to evaluate EVENT1. */ expr__ctx_clear(ctx); TEST_ASSERT_VAL("find ids", diff --git a/tools/perf/util/cputopo.c b/tools/perf/util/cputopo.c index d275d843c155..511002e52714 100644 --- a/tools/perf/util/cputopo.c +++ b/tools/perf/util/cputopo.c @@ -157,6 +157,21 @@ void cpu_topology__delete(struct cpu_topology *tp) free(tp); } +bool cpu_topology__smt_on(const struct cpu_topology *topology) +{ + for (u32 i = 0; i < topology->core_cpus_lists; i++) { + const char *cpu_list = topology->core_cpus_list[i]; + + /* + * If there is a need to separate siblings in a core then SMT is + * enabled. + */ + if (strchr(cpu_list, ',') || strchr(cpu_list, '-')) + return true; + } + return false; +} + static bool has_die_topology(void) { char filename[MAXPATHLEN]; diff --git a/tools/perf/util/cputopo.h b/tools/perf/util/cputopo.h index 854e18f9041e..469db775a13c 100644 --- a/tools/perf/util/cputopo.h +++ b/tools/perf/util/cputopo.h @@ -58,6 +58,8 @@ struct hybrid_topology { struct cpu_topology *cpu_topology__new(void); void cpu_topology__delete(struct cpu_topology *tp); +/* Determine from the core list whether SMT was enabled. */ +bool cpu_topology__smt_on(const struct cpu_topology *topology); struct numa_topology *numa_topology__new(void); void numa_topology__delete(struct numa_topology *tp); diff --git a/tools/perf/util/expr.c b/tools/perf/util/expr.c index 00bde682e743..8aa7dafa18b3 100644 --- a/tools/perf/util/expr.c +++ b/tools/perf/util/expr.c @@ -412,11 +412,6 @@ double expr__get_literal(const char *literal) static struct cpu_topology *topology; double result = NAN; - if (!strcasecmp("#smt_on", literal)) { - result = smt_on() > 0 ? 1.0 : 0.0; - goto out; - } - if (!strcmp("#num_cpus", literal)) { result = cpu__max_present_cpu().cpu; goto out; @@ -440,6 +435,10 @@ double expr__get_literal(const char *literal) goto out; } } + if (!strcasecmp("#smt_on", literal)) { + result = smt_on(topology) ? 1.0 : 0.0; + goto out; + } if (!strcmp("#num_packages", literal)) { result = topology->package_cpus_lists; goto out; diff --git a/tools/perf/util/smt.c b/tools/perf/util/smt.c index 8fed03283c85..ce90c4ee4138 100644 --- a/tools/perf/util/smt.c +++ b/tools/perf/util/smt.c @@ -1,100 +1,23 @@ // SPDX-License-Identifier: GPL-2.0-only -#include <stdio.h> -#include <stdlib.h> -#include <unistd.h> -#include <linux/bitops.h> +#include <string.h> #include "api/fs/fs.h" +#include "cputopo.h" #include "smt.h" -/** - * hweight_str - Returns the number of bits set in str. Stops at first non-hex - * or ',' character. - */ -static int hweight_str(char *str) -{ - int result = 0; - - while (*str) { - switch (*str++) { - case '0': - case ',': - break; - case '1': - case '2': - case '4': - case '8': - result++; - break; - case '3': - case '5': - case '6': - case '9': - case 'a': - case 'A': - case 'c': - case 'C': - result += 2; - break; - case '7': - case 'b': - case 'B': - case 'd': - case 'D': - case 'e': - case 'E': - result += 3; - break; - case 'f': - case 'F': - result += 4; - break; - default: - goto done; - } - } -done: - return result; -} - -int smt_on(void) +bool smt_on(const struct cpu_topology *topology) { static bool cached; - static int cached_result; - int cpu; - int ncpu; + static bool cached_result; + int fs_value; if (cached) return cached_result; - if (sysfs__read_int("devices/system/cpu/smt/active", &cached_result) >= 0) { - cached = true; - return cached_result; - } - - cached_result = 0; - ncpu = sysconf(_SC_NPROCESSORS_CONF); - for (cpu = 0; cpu < ncpu; cpu++) { - unsigned long long siblings; - char *str; - size_t strlen; - char fn[256]; + if (sysfs__read_int("devices/system/cpu/smt/active", &fs_value) >= 0) + cached_result = (fs_value == 1); + else + cached_result = cpu_topology__smt_on(topology); - snprintf(fn, sizeof fn, - "devices/system/cpu/cpu%d/topology/thread_siblings", cpu); - if (sysfs__read_str(fn, &str, &strlen) < 0) { - snprintf(fn, sizeof fn, - "devices/system/cpu/cpu%d/topology/core_cpus", cpu); - if (sysfs__read_str(fn, &str, &strlen) < 0) - continue; - } - /* Entry is hex, but does not have 0x, so need custom parser */ - siblings = hweight_str(str); - free(str); - if (siblings > 1) { - cached_result = 1; - break; - } - } cached = true; return cached_result; } diff --git a/tools/perf/util/smt.h b/tools/perf/util/smt.h index a98d65808f6a..e26999c6b8d4 100644 --- a/tools/perf/util/smt.h +++ b/tools/perf/util/smt.h @@ -2,6 +2,9 @@ #ifndef __SMT_H #define __SMT_H 1 -int smt_on(void); +struct cpu_topology; + +/* Returns true if SMT (aka hyperthreading) is enabled. */ +bool smt_on(const struct cpu_topology *topology); #endif /* __SMT_H */ |