Merge pull request #170 from oracle/optional-errs

libbpftune: only show errors on optional prog reload

Author: alan-maguire

include/bpftune/libbpftune.h

@@ -131,7 +131,7 @@ void bpftuner_cgroup_detach(struct bpftuner *tuner, const char *prog_name,
 
 
 struct bpftuner *bpftuner_init(const char *path);
-int __bpftuner_bpf_load(struct bpftuner *tuner, const char **optionals);
+int __bpftuner_bpf_load(struct bpftuner *tuner, const char **optionals, bool quiet);
 int __bpftuner_bpf_attach(struct bpftuner *tuner);
 
 int bpftuner_tunables_init(struct bpftuner *tuner, unsigned int num_descs,
@@ -251,12 +251,12 @@ void bpftuner_tunables_fini(struct bpftuner *tuner);
 #define bpftuner_bpf_load(tuner_name, tuner, optionals) ({		     \
 	int __err;							     \
 									     \
-	__err = __bpftuner_bpf_load(tuner, NULL);			     \
+	__err = __bpftuner_bpf_load(tuner, NULL, optionals != NULL);	     \
 	if (__err && optionals != NULL) {				     \
 		bpftuner_bpf_fini(tuner);				     \
 		__err = bpftuner_bpf_open(tuner_name, tuner);		     \
 		if (!__err)						     \
-			__err = __bpftuner_bpf_load(tuner, optionals);	     \
+			__err = __bpftuner_bpf_load(tuner, optionals, false);\
 	}								     \
 	if (__err)							     \
 		bpftuner_bpf_destroy(tuner_name, tuner);		     \

src/libbpftune.c

@@ -575,7 +575,7 @@ static void bpftuner_map_init(struct bpftuner *tuner, const char *name,
 	}
 }
 
-int __bpftuner_bpf_load(struct bpftuner *tuner, const char **optionals)
+int __bpftuner_bpf_load(struct bpftuner *tuner, const char **optionals, bool quiet)
 {
 	int err = 0;
 
@@ -590,7 +590,6 @@ int __bpftuner_bpf_load(struct bpftuner *tuner, const char **optionals)
 			       netns_map_fd, &tuner->netns_map_fd) ||
 	    bpftuner_map_reuse("corr_map", tuner->corr_map,
 			       corr_map_fd, &tuner->corr_map_fd)) {
-		bpftune_log(LOG_DEBUG, "got here!!\n");
 		err = -1;
 		goto out;
 	}
@@ -613,7 +612,10 @@ int __bpftuner_bpf_load(struct bpftuner *tuner, const char **optionals)
 		}
 	}
 	err = bpf_object__load_skeleton(tuner->skeleton);
-	if (err) {
+	/* only show errors when not in quiet mode (load with no optionals
+	 * or retry when loading without optionals failed.
+	 */
+	if (err && !quiet) {
 		switch (err) {
 		case -ESRCH:
 			bpftune_log(LOG_ERR, "tuner '%s' failed to load, tracing target was not found; this can occur for unstable tracing targets like kernel functions.\n",