From: Ian Rogers <irogers@google.com>
To: acme@kernel.org, namhyung@kernel.org
Cc: irogers@google.com, adrian.hunter@intel.com,
alexander.shishkin@linux.intel.com, ashelat@redhat.com,
ctshao@google.com, derek.foreman@collabora.com,
howardchu95@gmail.com, hrishikesh123s@gmail.com,
james.clark@linaro.org, jolsa@kernel.org,
linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org,
mingo@redhat.com, peterz@infradead.org, swapnil.sapkal@amd.com,
thomas.falcon@intel.com
Subject: [PATCH v4 3/8] perf header: Properly warn/print when libtraceevent/libbpf support is missing
Date: Wed, 1 Apr 2026 09:13:19 -0700 [thread overview]
Message-ID: <20260401161324.332356-4-irogers@google.com> (raw)
In-Reply-To: <20260401161324.332356-1-irogers@google.com>
By removing the features from feat_ops with ifdefs the previous logic
would print "# (null)" when perf processed a feature that lacked
builtin support. Remove the ifdefs from feat_ops and in the relevant
functions print errors/messages about the lack of support.
Signed-off-by: Ian Rogers <irogers@google.com>
---
| 70 +++++++++++++++++++++++++++-------------
1 file changed, 47 insertions(+), 23 deletions(-)
--git a/tools/perf/util/header.c b/tools/perf/util/header.c
index fcd53271e189..50c006be895f 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -306,16 +306,19 @@ static int do_read_bitmap(struct feat_fd *ff, unsigned long **pset, u64 *psize)
return 0;
}
-#ifdef HAVE_LIBTRACEEVENT
static int write_tracing_data(struct feat_fd *ff,
- struct evlist *evlist)
+ struct evlist *evlist __maybe_unused)
{
if (WARN(ff->buf, "Error: calling %s in pipe-mode.\n", __func__))
return -1;
+#ifdef HAVE_LIBTRACEEVENT
return read_tracing_data(ff->fd, &evlist->core.entries);
-}
+#else
+ pr_err("ERROR: Trying to write tracing data without libtraceevent support.\n");
+ return -1;
#endif
+}
static int write_build_id(struct feat_fd *ff,
struct evlist *evlist __maybe_unused)
@@ -1026,10 +1029,10 @@ static int write_dir_format(struct feat_fd *ff,
return do_write(ff, &data->dir.version, sizeof(data->dir.version));
}
-#ifdef HAVE_LIBBPF_SUPPORT
-static int write_bpf_prog_info(struct feat_fd *ff,
+static int write_bpf_prog_info(struct feat_fd *ff __maybe_unused,
struct evlist *evlist __maybe_unused)
{
+#ifdef HAVE_LIBBPF_SUPPORT
struct perf_env *env = &ff->ph->env;
struct rb_root *root;
struct rb_node *next;
@@ -1067,11 +1070,16 @@ static int write_bpf_prog_info(struct feat_fd *ff,
out:
up_read(&env->bpf_progs.lock);
return ret;
+#else
+ pr_err("ERROR: Trying to write bpf_prog_info without libbpf support.\n");
+ return -1;
+#endif // HAVE_LIBBPF_SUPPORT
}
-static int write_bpf_btf(struct feat_fd *ff,
+static int write_bpf_btf(struct feat_fd *ff __maybe_unused,
struct evlist *evlist __maybe_unused)
{
+#ifdef HAVE_LIBBPF_SUPPORT
struct perf_env *env = &ff->ph->env;
struct rb_root *root;
struct rb_node *next;
@@ -1100,8 +1108,11 @@ static int write_bpf_btf(struct feat_fd *ff,
out:
up_read(&env->bpf_progs.lock);
return ret;
-}
+#else
+ pr_err("ERROR: Trying to write btf data without libbpf support.\n");
+ return -1;
#endif // HAVE_LIBBPF_SUPPORT
+}
static int cpu_cache_level__sort(const void *a, const void *b)
{
@@ -1980,9 +1991,9 @@ static void print_dir_format(struct feat_fd *ff, FILE *fp)
fprintf(fp, "# directory data version : %"PRIu64"\n", data->dir.version);
}
-#ifdef HAVE_LIBBPF_SUPPORT
-static void print_bpf_prog_info(struct feat_fd *ff, FILE *fp)
+static void print_bpf_prog_info(struct feat_fd *ff __maybe_unused, FILE *fp)
{
+#ifdef HAVE_LIBBPF_SUPPORT
struct perf_env *env = &ff->ph->env;
struct rb_root *root;
struct rb_node *next;
@@ -1993,7 +2004,7 @@ static void print_bpf_prog_info(struct feat_fd *ff, FILE *fp)
next = rb_first(root);
if (!next)
- printf("# bpf_prog_info empty\n");
+ fprintf(fp, "# bpf_prog_info empty\n");
while (next) {
struct bpf_prog_info_node *node;
@@ -2006,10 +2017,14 @@ static void print_bpf_prog_info(struct feat_fd *ff, FILE *fp)
}
up_read(&env->bpf_progs.lock);
+#else
+ fprintf(fp, "# bpf_prog_info missing, no libbpf support\n");
+#endif // HAVE_LIBBPF_SUPPORT
}
-static void print_bpf_btf(struct feat_fd *ff, FILE *fp)
+static void print_bpf_btf(struct feat_fd *ff __maybe_unused, FILE *fp)
{
+#ifdef HAVE_LIBBPF_SUPPORT
struct perf_env *env = &ff->ph->env;
struct rb_root *root;
struct rb_node *next;
@@ -2031,8 +2046,10 @@ static void print_bpf_btf(struct feat_fd *ff, FILE *fp)
}
up_read(&env->bpf_progs.lock);
-}
+#else
+ fprintf(fp, "# bpf btf data missing, no libbpf support\n");
#endif // HAVE_LIBBPF_SUPPORT
+}
static void free_event_desc(struct evsel *events)
{
@@ -2644,14 +2661,17 @@ static int process_e_machine(struct feat_fd *ff, void *data __maybe_unused)
return do_read_u32(ff, &ff->ph->env.e_flags);
}
-#ifdef HAVE_LIBTRACEEVENT
-static int process_tracing_data(struct feat_fd *ff, void *data)
+static int process_tracing_data(struct feat_fd *ff __maybe_unused, void *data __maybe_unused)
{
+#ifdef HAVE_LIBTRACEEVENT
ssize_t ret = trace_report(ff->fd, data, false);
return ret < 0 ? -1 : 0;
-}
+#else
+ pr_err("ERROR: Trying to read tracing data without libtraceevent support.\n");
+ return -1;
#endif
+}
static int process_build_id(struct feat_fd *ff, void *data __maybe_unused)
{
@@ -3330,9 +3350,9 @@ static int process_dir_format(struct feat_fd *ff,
return do_read_u64(ff, &data->dir.version);
}
-#ifdef HAVE_LIBBPF_SUPPORT
-static int process_bpf_prog_info(struct feat_fd *ff, void *data __maybe_unused)
+static int process_bpf_prog_info(struct feat_fd *ff __maybe_unused, void *data __maybe_unused)
{
+#ifdef HAVE_LIBBPF_SUPPORT
struct bpf_prog_info_node *info_node;
struct perf_env *env = &ff->ph->env;
struct perf_bpil *info_linear;
@@ -3402,10 +3422,15 @@ static int process_bpf_prog_info(struct feat_fd *ff, void *data __maybe_unused)
free(info_node);
up_write(&env->bpf_progs.lock);
return err;
+#else
+ pr_err("ERROR: Trying to read bpf_prog_info without libbpf support.\n");
+ return -1;
+#endif // HAVE_LIBBPF_SUPPORT
}
-static int process_bpf_btf(struct feat_fd *ff, void *data __maybe_unused)
+static int process_bpf_btf(struct feat_fd *ff __maybe_unused, void *data __maybe_unused)
{
+#ifdef HAVE_LIBBPF_SUPPORT
struct perf_env *env = &ff->ph->env;
struct btf_node *node = NULL;
u32 count, i;
@@ -3449,8 +3474,11 @@ static int process_bpf_btf(struct feat_fd *ff, void *data __maybe_unused)
up_write(&env->bpf_progs.lock);
free(node);
return err;
-}
+#else
+ pr_err("ERROR: Trying to read btf data without libbpf support.\n");
+ return -1;
#endif // HAVE_LIBBPF_SUPPORT
+}
static int process_compressed(struct feat_fd *ff,
void *data __maybe_unused)
@@ -3726,9 +3754,7 @@ static int process_cpu_domain_info(struct feat_fd *ff, void *data __maybe_unused
const struct perf_header_feature_ops feat_ops[HEADER_LAST_FEATURE];
const struct perf_header_feature_ops feat_ops[HEADER_LAST_FEATURE] = {
-#ifdef HAVE_LIBTRACEEVENT
FEAT_OPN(TRACING_DATA, tracing_data, false),
-#endif
FEAT_OPN(BUILD_ID, build_id, false),
FEAT_OPR(HOSTNAME, hostname, false),
FEAT_OPR(OSRELEASE, osrelease, false),
@@ -3752,10 +3778,8 @@ const struct perf_header_feature_ops feat_ops[HEADER_LAST_FEATURE] = {
FEAT_OPR(MEM_TOPOLOGY, mem_topology, true),
FEAT_OPR(CLOCKID, clockid, false),
FEAT_OPN(DIR_FORMAT, dir_format, false),
-#ifdef HAVE_LIBBPF_SUPPORT
FEAT_OPR(BPF_PROG_INFO, bpf_prog_info, false),
FEAT_OPR(BPF_BTF, bpf_btf, false),
-#endif
FEAT_OPR(COMPRESSED, compressed, false),
FEAT_OPR(CPU_PMU_CAPS, cpu_pmu_caps, false),
FEAT_OPR(CLOCK_DATA, clock_data, false),
--
2.53.0.1118.gaef5881109-goog
next prev parent reply other threads:[~2026-04-01 16:13 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-02-28 6:59 [PATCH v2 0/7] perf data/pipe handling improvements Ian Rogers
2026-02-28 6:59 ` [PATCH v2 1/7] perf clockid: Add missing include Ian Rogers
2026-02-28 6:59 ` [PATCH v2 2/7] perf header: Add utility to convert feature number to a string Ian Rogers
2026-02-28 6:59 ` [PATCH v2 3/7] perf session: Extra logging for failed to process events Ian Rogers
2026-02-28 6:59 ` [PATCH v2 4/7] perf header: Refactor pipe mode end marker handling Ian Rogers
2026-03-05 6:23 ` Namhyung Kim
2026-04-01 5:26 ` Ian Rogers
2026-02-28 6:59 ` [PATCH v2 5/7] perf ordered-events: Event processing consistency with the regular reader Ian Rogers
2026-03-05 6:27 ` Namhyung Kim
2026-04-01 5:29 ` Ian Rogers
2026-02-28 6:59 ` [PATCH v2 6/7] perf evsel: Make unknown event names more unique Ian Rogers
2026-02-28 6:59 ` [PATCH v2 7/7] perf data convert ctf: Pipe mode improvements Ian Rogers
2026-03-05 6:39 ` Namhyung Kim
2026-04-01 5:51 ` [PATCH v3 0/7] perf data/pipe handling improvements Ian Rogers
2026-04-01 5:52 ` [PATCH v3 1/7] perf clockid: Add missing include Ian Rogers
2026-04-01 5:52 ` [PATCH v3 2/7] perf header: Add utility to convert feature number to a string Ian Rogers
2026-04-01 5:52 ` [PATCH v3 3/7] perf session: Extra logging for failed to process events Ian Rogers
2026-04-01 5:52 ` [PATCH v3 4/7] perf header: Refactor pipe mode end marker handling Ian Rogers
2026-04-01 5:52 ` [PATCH v3 5/7] perf ordered-events: Event processing consistency with the regular reader Ian Rogers
2026-04-01 5:52 ` [PATCH v3 6/7] perf evsel: Make unknown event names more unique Ian Rogers
2026-04-01 5:52 ` [PATCH v3 7/7] perf data convert ctf: Pipe mode improvements Ian Rogers
2026-04-01 16:13 ` [PATCH v4 0/8] perf data/pipe handling improvements Ian Rogers
2026-04-01 16:13 ` [PATCH v4 1/8] perf clockid: Add missing include Ian Rogers
2026-04-01 16:13 ` [PATCH v4 2/8] perf header: Add utility to convert feature number to a string Ian Rogers
2026-04-01 16:13 ` Ian Rogers [this message]
2026-04-01 16:13 ` [PATCH v4 4/8] perf session: Extra logging for failed to process events Ian Rogers
2026-04-01 16:13 ` [PATCH v4 5/8] perf header: Refactor pipe mode end marker handling Ian Rogers
2026-04-01 16:13 ` [PATCH v4 6/8] perf ordered-events: Event processing consistency with the regular reader Ian Rogers
2026-04-01 16:13 ` [PATCH v4 7/8] perf evsel: Make unknown event names more unique Ian Rogers
2026-04-01 16:13 ` [PATCH v4 8/8] perf data convert ctf: Pipe mode improvements Ian Rogers
2026-04-04 0:15 ` [PATCH v4 0/8] perf data/pipe handling improvements Namhyung Kim
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