perf namespaces: Add functions to access nsinfo

Having functions to access nsinfo reduces the places where reference
counting checking needs to be added.
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: André Almeida <andrealmeid@collabora.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Hao Luo <haoluo@google.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.garry@huawei.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Miaoqian Lin <linmq006@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Shunsuke Nakamura <nakamura.shun@fujitsu.com>
Cc: Song Liu <song@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Yury Norov <yury.norov@gmail.com>
Link: http://lore.kernel.org/lkml/20220211103415.2737789-14-irogers@google.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-inject.c

@@ -356,7 +356,7 @@ static struct dso *findnew_dso(int pid, int tid, const char *filename,
 		nnsi = nsinfo__copy(nsi);
 		if (nnsi) {
 			nsinfo__put(nsi);
-			nnsi->need_setns = false;
+			nsinfo__clear_need_setns(nnsi);
 			nsi = nnsi;
 		}
 		dso = machine__findnew_vdso(machine, thread);

tools/perf/builtin-probe.c

@@ -217,7 +217,7 @@ static int opt_set_target_ns(const struct option *opt __maybe_unused,
 			return ret;
 		}
 		nsip = nsinfo__new(ns_pid);
-		if (nsip && nsip->need_setns)
+		if (nsip && nsinfo__need_setns(nsip))
 			params.nsi = nsinfo__get(nsip);
 		nsinfo__put(nsip);
 

tools/perf/util/build-id.c

@@ -706,7 +706,7 @@ build_id_cache__add(const char *sbuild_id, const char *name, const char *realnam
 		if (is_kallsyms) {
 			if (copyfile("/proc/kallsyms", filename))
 				goto out_free;
-		} else if (nsi && nsi->need_setns) {
+		} else if (nsi && nsinfo__need_setns(nsi)) {
 			if (copyfile_ns(name, filename, nsi))
 				goto out_free;
 		} else if (link(realname, filename) && errno != EEXIST &&
@@ -730,7 +730,7 @@ build_id_cache__add(const char *sbuild_id, const char *name, const char *realnam
 				goto out_free;
 			}
 			if (access(filename, F_OK)) {
-				if (nsi && nsi->need_setns) {
+				if (nsi && nsinfo__need_setns(nsi)) {
 					if (copyfile_ns(debugfile, filename,
 							nsi))
 						goto out_free;

tools/perf/util/jitdump.c

@@ -382,15 +382,15 @@ jit_inject_event(struct jit_buf_desc *jd, union perf_event *event)
 
 static pid_t jr_entry_pid(struct jit_buf_desc *jd, union jr_entry *jr)
 {
-	if (jd->nsi && jd->nsi->in_pidns)
-		return jd->nsi->tgid;
+	if (jd->nsi && nsinfo__in_pidns(jd->nsi))
+		return nsinfo__tgid(jd->nsi);
 	return jr->load.pid;
 }
 
 static pid_t jr_entry_tid(struct jit_buf_desc *jd, union jr_entry *jr)
 {
-	if (jd->nsi && jd->nsi->in_pidns)
-		return jd->nsi->pid;
+	if (jd->nsi && nsinfo__in_pidns(jd->nsi))
+		return nsinfo__pid(jd->nsi);
 	return jr->load.tid;
 }
 
@@ -779,7 +779,7 @@ jit_detect(char *mmap_name, pid_t pid, struct nsinfo *nsi)
 	 * pid does not match mmap pid
 	 * pid==0 in system-wide mode (synthesized)
 	 */
-	if (pid && pid2 != nsi->nstgid)
+	if (pid && pid2 != nsinfo__nstgid(nsi))
 		return -1;
 	/*
 	 * validate suffix

tools/perf/util/map.c

@@ -151,7 +151,7 @@ struct map *map__new(struct machine *machine, u64 start, u64 len,
 
 		if ((anon || no_dso) && nsi && (prot & PROT_EXEC)) {
 			snprintf(newfilename, sizeof(newfilename),
-				 "/tmp/perf-%d.map", nsi->pid);
+				 "/tmp/perf-%d.map", nsinfo__pid(nsi));
 			filename = newfilename;
 		}
 
@@ -168,7 +168,7 @@ struct map *map__new(struct machine *machine, u64 start, u64 len,
 			nnsi = nsinfo__copy(nsi);
 			if (nnsi) {
 				nsinfo__put(nsi);
-				nnsi->need_setns = false;
+				nsinfo__clear_need_setns(nnsi);
 				nsi = nnsi;
 			}
 			pgoff = 0;

tools/perf/util/namespaces.c

@@ -76,7 +76,7 @@ static int nsinfo__get_nspid(struct nsinfo *nsi, const char *path)
 		if (strstr(statln, "Tgid:") != NULL) {
 			nsi->tgid = (pid_t)strtol(strrchr(statln, '\t'),
 						     NULL, 10);
-			nsi->nstgid = nsi->tgid;
+			nsi->nstgid = nsinfo__tgid(nsi);
 		}
 
 		if (strstr(statln, "NStgid:") != NULL) {
@@ -108,7 +108,7 @@ int nsinfo__init(struct nsinfo *nsi)
 	if (snprintf(oldns, PATH_MAX, "/proc/self/ns/mnt") >= PATH_MAX)
 		return rv;
 
-	if (asprintf(&newns, "/proc/%d/ns/mnt", nsi->pid) == -1)
+	if (asprintf(&newns, "/proc/%d/ns/mnt", nsinfo__pid(nsi)) == -1)
 		return rv;
 
 	if (stat(oldns, &old_stat) < 0)
@@ -129,7 +129,7 @@ int nsinfo__init(struct nsinfo *nsi)
 	/* If we're dealing with a process that is in a different PID namespace,
 	 * attempt to work out the innermost tgid for the process.
 	 */
-	if (snprintf(spath, PATH_MAX, "/proc/%d/status", nsi->pid) >= PATH_MAX)
+	if (snprintf(spath, PATH_MAX, "/proc/%d/status", nsinfo__pid(nsi)) >= PATH_MAX)
 		goto out;
 
 	rv = nsinfo__get_nspid(nsi, spath);
@@ -166,7 +166,7 @@ struct nsinfo *nsinfo__new(pid_t pid)
 	return nsi;
 }
 
-struct nsinfo *nsinfo__copy(struct nsinfo *nsi)
+struct nsinfo *nsinfo__copy(const struct nsinfo *nsi)
 {
 	struct nsinfo *nnsi;
 
@@ -175,11 +175,11 @@ struct nsinfo *nsinfo__copy(struct nsinfo *nsi)
 
 	nnsi = calloc(1, sizeof(*nnsi));
 	if (nnsi != NULL) {
-		nnsi->pid = nsi->pid;
-		nnsi->tgid = nsi->tgid;
-		nnsi->nstgid = nsi->nstgid;
-		nnsi->need_setns = nsi->need_setns;
-		nnsi->in_pidns = nsi->in_pidns;
+		nnsi->pid = nsinfo__pid(nsi);
+		nnsi->tgid = nsinfo__tgid(nsi);
+		nnsi->nstgid = nsinfo__nstgid(nsi);
+		nnsi->need_setns = nsinfo__need_setns(nsi);
+		nnsi->in_pidns = nsinfo__in_pidns(nsi);
 		if (nsi->mntns_path) {
 			nnsi->mntns_path = strdup(nsi->mntns_path);
 			if (!nnsi->mntns_path) {
@@ -193,7 +193,7 @@ struct nsinfo *nsinfo__copy(struct nsinfo *nsi)
 	return nnsi;
 }
 
-void nsinfo__delete(struct nsinfo *nsi)
+static void nsinfo__delete(struct nsinfo *nsi)
 {
 	zfree(&nsi->mntns_path);
 	free(nsi);
@@ -212,6 +212,36 @@ void nsinfo__put(struct nsinfo *nsi)
 		nsinfo__delete(nsi);
 }
 
+bool nsinfo__need_setns(const struct nsinfo *nsi)
+{
+        return nsi->need_setns;
+}
+
+void nsinfo__clear_need_setns(struct nsinfo *nsi)
+{
+        nsi->need_setns = false;
+}
+
+pid_t nsinfo__tgid(const struct nsinfo  *nsi)
+{
+        return nsi->tgid;
+}
+
+pid_t nsinfo__nstgid(const struct nsinfo  *nsi)
+{
+        return nsi->nstgid;
+}
+
+pid_t nsinfo__pid(const struct nsinfo  *nsi)
+{
+        return nsi->pid;
+}
+
+pid_t nsinfo__in_pidns(const struct nsinfo  *nsi)
+{
+        return nsi->in_pidns;
+}
+
 void nsinfo__mountns_enter(struct nsinfo *nsi,
 				  struct nscookie *nc)
 {

tools/perf/util/namespaces.h

@@ -47,12 +47,18 @@ struct nscookie {
 
 int nsinfo__init(struct nsinfo *nsi);
 struct nsinfo *nsinfo__new(pid_t pid);
-struct nsinfo *nsinfo__copy(struct nsinfo *nsi);
-void nsinfo__delete(struct nsinfo *nsi);
+struct nsinfo *nsinfo__copy(const struct nsinfo *nsi);
 
 struct nsinfo *nsinfo__get(struct nsinfo *nsi);
 void nsinfo__put(struct nsinfo *nsi);
 
+bool nsinfo__need_setns(const struct nsinfo *nsi);
+void nsinfo__clear_need_setns(struct nsinfo *nsi);
+pid_t nsinfo__tgid(const struct nsinfo  *nsi);
+pid_t nsinfo__nstgid(const struct nsinfo  *nsi);
+pid_t nsinfo__pid(const struct nsinfo  *nsi);
+pid_t nsinfo__in_pidns(const struct nsinfo  *nsi);
+
 void nsinfo__mountns_enter(struct nsinfo *nsi, struct nscookie *nc);
 void nsinfo__mountns_exit(struct nscookie *nc);
 

tools/perf/util/symbol.c

@@ -1735,8 +1735,8 @@ static int dso__find_perf_map(char *filebuf, size_t bufsz,
 
 	nsi = *nsip;
 
-	if (nsi->need_setns) {
-		snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsi->nstgid);
+	if (nsinfo__need_setns(nsi)) {
+		snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsinfo__nstgid(nsi));
 		nsinfo__mountns_enter(nsi, &nsc);
 		rc = access(filebuf, R_OK);
 		nsinfo__mountns_exit(&nsc);
@@ -1748,8 +1748,8 @@ static int dso__find_perf_map(char *filebuf, size_t bufsz,
 	if (nnsi) {
 		nsinfo__put(nsi);
 
-		nnsi->need_setns = false;
-		snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nnsi->tgid);
+		nsinfo__clear_need_setns(nnsi);
+		snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsinfo__tgid(nnsi));
 		*nsip = nnsi;
 		rc = 0;
 	}