The control knobs set before loading BPF programs should be declared as
'const volatile' so that it can be optimized by the BPF core.
Cc: Yang Jihong <yangjihong@xxxxxxxxxxxxx>
Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
---
tools/perf/util/bpf_kwork.c | 9 +++++----
tools/perf/util/bpf_kwork_top.c | 7 ++++---
tools/perf/util/bpf_skel/kwork_top.bpf.c | 2 +-
tools/perf/util/bpf_skel/kwork_trace.bpf.c | 5 +++--
4 files changed, 13 insertions(+), 10 deletions(-)
diff --git a/tools/perf/util/bpf_kwork.c b/tools/perf/util/bpf_kwork.c
index 44f0f708a15d6a14..6c7126b7670dd0c9 100644
--- a/tools/perf/util/bpf_kwork.c
+++ b/tools/perf/util/bpf_kwork.c
@@ -176,8 +176,6 @@ static int setup_filters(struct perf_kwork *kwork)
bpf_map_update_elem(fd, &cpu.cpu, &val, BPF_ANY);
}
perf_cpu_map__put(map);
-
- skel->bss->has_cpu_filter = 1;
}
if (kwork->profile_name != NULL) {
@@ -197,8 +195,6 @@ static int setup_filters(struct perf_kwork *kwork)
key = 0;
bpf_map_update_elem(fd, &key, kwork->profile_name, BPF_ANY);
-
- skel->bss->has_name_filter = 1;
}
return 0;
@@ -239,6 +235,11 @@ int perf_kwork__trace_prepare_bpf(struct perf_kwork *kwork)
class_bpf->load_prepare(kwork);
}
+ if (kwork->cpu_list != NULL)
+ skel->rodata->has_cpu_filter = 1;
+ if (kwork->profile_name != NULL)
+ skel->rodata->has_name_filter = 1;
+
if (kwork_trace_bpf__load(skel)) {
pr_debug("Failed to load kwork trace skeleton\n");
goto out;
diff --git a/tools/perf/util/bpf_kwork_top.c b/tools/perf/util/bpf_kwork_top.c
index 22a3b00a1e23f929..7261cad43468d7a4 100644
--- a/tools/perf/util/bpf_kwork_top.c
+++ b/tools/perf/util/bpf_kwork_top.c
@@ -151,14 +151,12 @@ static int setup_filters(struct perf_kwork *kwork)
bpf_map_update_elem(fd, &cpu.cpu, &val, BPF_ANY);
}
perf_cpu_map__put(map);
-
- skel->bss->has_cpu_filter = 1;
}
return 0;
}
-int perf_kwork__top_prepare_bpf(struct perf_kwork *kwork __maybe_unused)
+int perf_kwork__top_prepare_bpf(struct perf_kwork *kwork)
{
struct bpf_program *prog;
struct kwork_class *class;
@@ -193,6 +191,9 @@ int perf_kwork__top_prepare_bpf(struct perf_kwork *kwork __maybe_unused)
class_bpf->load_prepare();
}
+ if (kwork->cpu_list)
+ skel->rodata->has_cpu_filter = 1;
+
if (kwork_top_bpf__load(skel)) {
pr_debug("Failed to load kwork top skeleton\n");
goto out;
diff --git a/tools/perf/util/bpf_skel/kwork_top.bpf.c b/tools/perf/util/bpf_skel/kwork_top.bpf.c
index 84c15ccbab44ccc9..594da91965a2f6c9 100644
--- a/tools/perf/util/bpf_skel/kwork_top.bpf.c
+++ b/tools/perf/util/bpf_skel/kwork_top.bpf.c
@@ -84,7 +84,7 @@ struct {
int enabled = 0;
-int has_cpu_filter = 0;
+const volatile int has_cpu_filter = 0;
__u64 from_timestamp = 0;
__u64 to_timestamp = 0;
diff --git a/tools/perf/util/bpf_skel/kwork_trace.bpf.c b/tools/perf/util/bpf_skel/kwork_trace.bpf.c
index 063c124e099938ed..cbd79bc4b3302d81 100644
--- a/tools/perf/util/bpf_skel/kwork_trace.bpf.c
+++ b/tools/perf/util/bpf_skel/kwork_trace.bpf.c
@@ -68,8 +68,9 @@ struct {
} perf_kwork_name_filter SEC(".maps");
int enabled = 0;
-int has_cpu_filter = 0;
-int has_name_filter = 0;
+
+const volatile int has_cpu_filter = 0;
+const volatile int has_name_filter = 0;
static __always_inline int local_strncmp(const char *s1,
unsigned int sz, const char *s2)
--
2.46.0.469.g59c65b2a67-goog
