diff options
| author | Ian Rogers <irogers@google.com> | 2023-03-24 00:22:17 -0700 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2023-04-04 09:39:55 -0300 |
| commit | c3bf86f11dc9a11afb83b33f9640bf86adfb1b28 (patch) | |
| tree | 52f189e35c08ab61be2b35d669109e72943dc021 /tools/perf/util/expr.c | |
| parent | e559b6f53b1b36fd69291962104fa86edf3dadf4 (diff) | |
perf metrics: Add has_pmem literal
Add literal so that if nvdimms aren't installed we can record fewer
events. The file detection mechanism was suggested by Dan Williams
<dan.j.williams@intel.com> in:
https://lore.kernel.org/linux-perf-users/641bbe1eced26_1b98bb29440@dwillia2-xfh.jf.intel.com.notmuch/
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Caleb Biggers <caleb.biggers@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Edward Baker <edward.baker@intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
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: Weilin Wang <weilin.wang@intel.com>
Cc: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Link: https://lore.kernel.org/r/20230324072218.181880-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/expr.c')
| -rw-r--r-- | tools/perf/util/expr.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/tools/perf/util/expr.c b/tools/perf/util/expr.c index d46a1878bc9e..bb6ddad7e021 100644 --- a/tools/perf/util/expr.c +++ b/tools/perf/util/expr.c @@ -14,6 +14,7 @@ #include "util/hashmap.h" #include "smt.h" #include "tsc.h" +#include <api/fs/fs.h> #include <linux/err.h> #include <linux/kernel.h> #include <linux/zalloc.h> @@ -400,6 +401,20 @@ double arch_get_tsc_freq(void) } #endif +static double has_pmem(void) +{ + static bool has_pmem, cached; + const char *sysfs = sysfs__mountpoint(); + char path[PATH_MAX]; + + if (!cached) { + snprintf(path, sizeof(path), "%s/firmware/acpi/tables/NFIT", sysfs); + has_pmem = access(path, F_OK) == 0; + cached = true; + } + return has_pmem ? 1.0 : 0.0; +} + double expr__get_literal(const char *literal, const struct expr_scanner_ctx *ctx) { const struct cpu_topology *topology; @@ -449,6 +464,10 @@ double expr__get_literal(const char *literal, const struct expr_scanner_ctx *ctx result = perf_pmu__cpu_slots_per_cycle(); goto out; } + if (!strcmp("#has_pmem", literal)) { + result = has_pmem(); + goto out; + } pr_err("Unrecognized literal '%s'", literal); out: |