[RFC PATCH v1 29/37] perf evlist: add custom fallback to evlist__open
From: Riccardo Mancini <hidden>
Date: 2021-08-21 09:22:22
Also in:
lkml
Subsystem:
performance events subsystem, the rest · Maintainers:
Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Namhyung Kim, Linus Torvalds
This patch adds the function evlist__open_custom, which makes it possible to provide a custom fallback mechanism to evsel__open. This function will be used in record__open in the following patch. This could also be used to adapt perf-stat way of opening to the new multithreaded mechanism. Signed-off-by: Riccardo Mancini <redacted> --- tools/perf/util/evlist.c | 27 +++++++++++++++++++++------ tools/perf/util/evlist.h | 9 +++++++++ 2 files changed, 30 insertions(+), 6 deletions(-)
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 3472038d719ec7d4..22b9607dcc637a2d 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c@@ -1405,15 +1405,20 @@ static int evlist__create_syswide_maps(struct evlist *evlist) return err; } -static int evlist__open_singlethreaded(struct evlist *evlist) +static int evlist__open_singlethreaded(struct evlist *evlist, + struct evlist_open_custom_fallback *cust_fb) { struct evsel *evsel; int err; evlist__for_each_entry(evlist, evsel) { +try_again: err = evsel__open(evsel, evsel->core.cpus, evsel->core.threads); - if (err < 0) + if (err < 0) { + if (cust_fb && cust_fb->func(cust_fb, evlist, evsel, err)) + goto try_again; return err; + } } return 0;
@@ -1469,7 +1474,8 @@ static void evlist__open_multithreaded_func(struct work_struct *_work) } } -static int evlist__open_multithreaded(struct evlist *evlist) +static int evlist__open_multithreaded(struct evlist *evlist, + struct evlist_open_custom_fallback *cust_fb) { int cpu, cpuid, cpuidx, thread, err; struct evlist_open_work *works;
@@ -1567,6 +1573,9 @@ static int evlist__open_multithreaded(struct evlist *evlist) if (evsel__detect_missing_features(evsel)) goto reprepare; + if (cust_fb && cust_fb->func(cust_fb, evlist, evsel, err)) + goto reprepare; + // no fallback worked, return the error goto out; }
@@ -1579,7 +1588,8 @@ static int evlist__open_multithreaded(struct evlist *evlist) return err; } -int evlist__open(struct evlist *evlist) +int evlist__open_custom(struct evlist *evlist, + struct evlist_open_custom_fallback *cust_fb) { int err;
@@ -1596,9 +1606,9 @@ int evlist__open(struct evlist *evlist) evlist__update_id_pos(evlist); if (perf_singlethreaded) - err = evlist__open_singlethreaded(evlist); + err = evlist__open_singlethreaded(evlist, cust_fb); else - err = evlist__open_multithreaded(evlist); + err = evlist__open_multithreaded(evlist, cust_fb); if (err) goto out_err;
@@ -1610,6 +1620,11 @@ int evlist__open(struct evlist *evlist) return err; } +int evlist__open(struct evlist *evlist) +{ + return evlist__open_custom(evlist, NULL); +} + int evlist__prepare_workload(struct evlist *evlist, struct target *target, const char *argv[], bool pipe_output, void (*exec_error)(int signo, siginfo_t *info, void *ucontext)) {
diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
index b0c2da0f9755b2d1..cb753b4c4e70b4ba 100644
--- a/tools/perf/util/evlist.h
+++ b/tools/perf/util/evlist.h@@ -161,6 +161,15 @@ void evlist__mmap_consume(struct evlist *evlist, int idx); int evlist__open(struct evlist *evlist); void evlist__close(struct evlist *evlist); +struct evlist_open_custom_fallback; +typedef bool (*evlist_open_custom_fallback_fn)(struct evlist_open_custom_fallback *fallback, + struct evlist *evlist, struct evsel *evsel, int err); +struct evlist_open_custom_fallback { + evlist_open_custom_fallback_fn func; +}; +int evlist__open_custom(struct evlist *evlist, struct evlist_open_custom_fallback *cust_fb); + + struct callchain_param; void evlist__set_id_pos(struct evlist *evlist);
--
2.31.1