perf session: Return error code for perf_session__new() function on failure

This patch is to return error code of perf_new_session function on
failure instead of NULL.

Test Results:

Before Fix:

$ perf c2c report -input
failed to open nput: No such file or directory

$ echo $?
0
$

After Fix:

$ perf c2c report -input
failed to open nput: No such file or directory

$ echo $?
254
$

Committer notes:

Fix 'perf tests topology' case, where we use that TEST_ASSERT_VAL(...,
session), i.e. we need to pass zero in case of failure, which was the
case before when NULL was returned by perf_session__new() for failure,
but now we need to negate the result of IS_ERR(session) to respect that
TEST_ASSERT_VAL) expectation of zero meaning failure.

Reported-by: Nageswara R Sastry <[e-mail]>
Signed-off-by: Mamatha Inamdar <[e-mail]>
Tested-by: Arnaldo Carvalho de Melo <[e-mail]>
Tested-by: Nageswara R Sastry <[e-mail]>
Acked-by: Ravi Bangoria <[e-mail]>
Reviewed-by: Jiri Olsa <[e-mail]>
Reviewed-by: Mukesh Ojha <[e-mail]>
Cc: Adrian Hunter <[e-mail]>
Cc: Alexander Shishkin <[e-mail]>
Cc: Alexey Budankov <[e-mail]>
Cc: Greg Kroah-Hartman <[e-mail]>
Cc: Jeremie Galarneau <[e-mail]>
Cc: Kate Stewart <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Shawn Landden <[e-mail]>
Cc: Song Liu <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Cc: Tzvetomir Stoyanov <[e-mail]>
Link: http://lore.kernel.org/lkml/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/builtin-annotate.c

···
 #include <dlfcn.h>
 #include <errno.h>
 #include <linux/bitmap.h>
+#include <linux/err.h>
 
 struct perf_annotate {
 	struct perf_tool tool;
···
 	data.path = input_name;
 
 	annotate.session = perf_session__new(&data, false, &annotate.tool);
-	if (annotate.session == NULL)
-		return -1;
+	if (IS_ERR(annotate.session))
+		return PTR_ERR(annotate.session);
 
 	annotate.has_br_stack = perf_header__has_feat(&annotate.session->header,
 						      HEADER_BRANCH_STACK);

tools/perf/builtin-buildid-cache.c

···
 #include "util/util.h"
 #include "util/probe-file.h"
 #include <linux/string.h>
+#include <linux/err.h>
 
 static int build_id_cache__kcore_buildid(const char *proc_dir, char *sbuildid)
 {
···
 		data.force = force;
 
 		session = perf_session__new(&data, false, NULL);
-		if (session == NULL)
-			return -1;
+		if (IS_ERR(session))
+			return PTR_ERR(session);
 	}
 
 	if (symbol__init(session ? &session->header.env : NULL) < 0)

tools/perf/builtin-buildid-list.c

···
 #include "util/symbol.h"
 #include "util/data.h"
 #include <errno.h>
+#include <linux/err.h>
 
 static int sysfs__fprintf_build_id(FILE *fp)
 {
···
 		goto out;
 
 	session = perf_session__new(&data, false, &build_id__mark_dso_hit_ops);
-	if (session == NULL)
-		return -1;
+	if (IS_ERR(session))
+		return PTR_ERR(session);
 
 	/*
 	 * We take all buildids when the file contains AUX area tracing data

tools/perf/builtin-c2c.c

···
 #include <errno.h>
 #include <inttypes.h>
 #include <linux/compiler.h>
+#include <linux/err.h>
 #include <linux/kernel.h>
 #include <linux/stringify.h>
 #include <linux/zalloc.h>
···
 	}
 
 	session = perf_session__new(&data, 0, &c2c.tool);
-	if (session == NULL) {
-		pr_debug("No memory for session\n");
+	if (IS_ERR(session)) {
+		err = PTR_ERR(session);
+		pr_debug("Error creating perf session\n");
 		goto out;
 	}
 

tools/perf/builtin-diff.c

···
 #include "util/time-utils.h"
 #include "util/annotate.h"
 #include "util/map.h"
+#include <linux/err.h>
 #include <linux/zalloc.h>
 #include <subcmd/pager.h>
 #include <subcmd/parse-options.h>
···
 
 	data__for_each_file(i, d) {
 		d->session = perf_session__new(&d->data, false, &pdiff.tool);
-		if (!d->session) {
+		if (IS_ERR(d->session)) {
 			pr_err("Failed to open %s\n", d->data.path);
-			return -1;
+			return PTR_ERR(d->session);
 		}
 
 		has_br_stack = perf_header__has_feat(&d->session->header,
···
 
 	data__for_each_file(i, d) {
 		d->session = perf_session__new(&d->data, false, &pdiff.tool);
-		if (!d->session) {
+		if (IS_ERR(d->session)) {
+			ret = PTR_ERR(d->session);
 			pr_err("Failed to open %s\n", d->data.path);
-			ret = -1;
 			goto out_delete;
 		}
 

tools/perf/builtin-evlist.c

···
 #include "util/session.h"
 #include "util/data.h"
 #include "util/debug.h"
+#include <linux/err.h>
 
 static int __cmd_evlist(const char *file_name, struct perf_attr_details *details)
 {
···
 	bool has_tracepoint = false;
 
 	session = perf_session__new(&data, 0, NULL);
-	if (session == NULL)
-		return -1;
+	if (IS_ERR(session))
+		return PTR_ERR(session);
 
 	evlist__for_each_entry(session->evlist, pos) {
 		perf_evsel__fprintf(pos, details, stdout);

tools/perf/builtin-inject.c

···
 #include "util/symbol.h"
 #include "util/synthetic-events.h"
 #include "util/thread.h"
+#include <linux/err.h>
 
 #include <subcmd/parse-options.h>
 
···
 
 	data.path = inject.input_name;
 	inject.session = perf_session__new(&data, true, &inject.tool);
-	if (inject.session == NULL)
-		return -1;
+	if (IS_ERR(inject.session))
+		return PTR_ERR(inject.session);
 
 	if (zstd_init(&(inject.session->zstd_data), 0) < 0)
 		pr_warning("Decompression initialization failed.\n");

tools/perf/builtin-kmem.c

···
 #include "util/tool.h"
 #include "util/callchain.h"
 #include "util/time-utils.h"
+#include <linux/err.h>
 
 #include <subcmd/pager.h>
 #include <subcmd/parse-options.h>
···
 	data.path = input_name;
 
 	kmem_session = session = perf_session__new(&data, false, &perf_kmem);
-	if (session == NULL)
-		return -1;
+	if (IS_ERR(session))
+		return PTR_ERR(session);
 
 	ret = -1;
 

tools/perf/builtin-kvm.c

···
 #include <sys/stat.h>
 #include <fcntl.h>
 
+#include <linux/err.h>
 #include <linux/kernel.h>
 #include <linux/string.h>
 #include <linux/time64.h>
···
 
 	kvm->tool = eops;
 	kvm->session = perf_session__new(&file, false, &kvm->tool);
-	if (!kvm->session) {
+	if (IS_ERR(kvm->session)) {
 		pr_err("Initializing perf session failed\n");
-		return -1;
+		return PTR_ERR(kvm->session);
 	}
 
 	symbol__init(&kvm->session->header.env);
···
 	 * perf session
 	 */
 	kvm->session = perf_session__new(&data, false, &kvm->tool);
-	if (kvm->session == NULL) {
-		err = -1;
+	if (IS_ERR(kvm->session)) {
+		err = PTR_ERR(kvm->session);
 		goto out;
 	}
 	kvm->session->evlist = kvm->evlist;

tools/perf/builtin-lock.c

···
 #include <linux/hash.h>
 #include <linux/kernel.h>
 #include <linux/zalloc.h>
+#include <linux/err.h>
 
 static struct perf_session *session;
 
···
 	};
 
 	session = perf_session__new(&data, false, &eops);
-	if (!session) {
+	if (IS_ERR(session)) {
 		pr_err("Initializing perf session failed\n");
-		return -1;
+		return PTR_ERR(session);
 	}
 
 	symbol__init(&session->header.env);

tools/perf/builtin-mem.c

···
 #include "util/dso.h"
 #include "util/map.h"
 #include "util/symbol.h"
+#include <linux/err.h>
 
 #define MEM_OPERATION_LOAD	0x1
 #define MEM_OPERATION_STORE	0x2
···
 	struct perf_session *session = perf_session__new(&data, false,
 							 &mem->tool);
 
-	if (session == NULL)
-		return -1;
+	if (IS_ERR(session))
+		return PTR_ERR(session);
 
 	if (mem->cpu_list) {
 		ret = perf_session__cpu_bitmap(session, mem->cpu_list,

tools/perf/builtin-record.c

···
 #include <signal.h>
 #include <sys/mman.h>
 #include <sys/wait.h>
+#include <linux/err.h>
 #include <linux/string.h>
 #include <linux/time64.h>
 #include <linux/zalloc.h>
···
 	}
 
 	session = perf_session__new(data, false, tool);
-	if (session == NULL) {
+	if (IS_ERR(session)) {
 		pr_err("Perf session creation failed.\n");
-		return -1;
+		return PTR_ERR(session);
 	}
 
 	fd = perf_data__fd(data);

tools/perf/builtin-report.c

···
 
 repeat:
 	session = perf_session__new(&data, false, &report.tool);
-	if (session == NULL)
-		return -1;
+	if (IS_ERR(session))
+		return PTR_ERR(session);
 
 	ret = evswitch__init(&report.evswitch, session->evlist, stderr);
 	if (ret)

tools/perf/builtin-sched.c

···
 #include <api/fs/fs.h>
 #include <perf/cpumap.h>
 #include <linux/time64.h>
+#include <linux/err.h>
 
 #include <linux/ctype.h>
 
···
 	int rc = -1;
 
 	session = perf_session__new(&data, false, &sched->tool);
-	if (session == NULL) {
-		pr_debug("No Memory for session\n");
-		return -1;
+	if (IS_ERR(session)) {
+		pr_debug("Error creating perf session");
+		return PTR_ERR(session);
 	}
 
 	symbol__init(&session->header.env);
···
 	symbol_conf.use_callchain = sched->show_callchain;
 
 	session = perf_session__new(&data, false, &sched->tool);
-	if (session == NULL)
-		return -ENOMEM;
+	if (IS_ERR(session))
+		return PTR_ERR(session);
 
 	evlist = session->evlist;
 

tools/perf/builtin-script.c

···
 #include <unistd.h>
 #include <subcmd/pager.h>
 #include <perf/evlist.h>
+#include <linux/err.h>
 #include "util/record.h"
 #include "util/util.h"
 #include "perf.h"
···
 	int i = 0;
 
 	session = perf_session__new(&data, false, NULL);
-	if (!session)
-		return -1;
+	if (IS_ERR(session))
+		return PTR_ERR(session);
 
 	snprintf(scripts_path, MAXPATHLEN, "%s/scripts", get_argv_exec_path());
 
···
 	}
 
 	session = perf_session__new(&data, false, &script.tool);
-	if (session == NULL)
-		return -1;
+	if (IS_ERR(session))
+		return PTR_ERR(session);
 
 	if (header || header_only) {
 		script.tool.show_feat_hdr = SHOW_FEAT_HEADER;

tools/perf/builtin-stat.c

···
 #include <unistd.h>
 #include <sys/time.h>
 #include <sys/resource.h>
+#include <linux/err.h>
 
 #include <linux/ctype.h>
 #include <perf/evlist.h>
···
 	}
 
 	session = perf_session__new(data, false, NULL);
-	if (session == NULL) {
-		pr_err("Perf session creation failed.\n");
-		return -1;
+	if (IS_ERR(session)) {
+		pr_err("Perf session creation failed\n");
+		return PTR_ERR(session);
 	}
 
 	init_features(session);
···
 	perf_stat.data.mode = PERF_DATA_MODE_READ;
 
 	session = perf_session__new(&perf_stat.data, false, &perf_stat.tool);
-	if (session == NULL)
-		return -1;
+	if (IS_ERR(session))
+		return PTR_ERR(session);
 
 	perf_stat.session  = session;
 	stat_config.output = stderr;

tools/perf/builtin-timechart.c

···
 #include "util/tool.h"
 #include "util/data.h"
 #include "util/debug.h"
+#include <linux/err.h>
 
 #ifdef LACKS_OPEN_MEMSTREAM_PROTOTYPE
 FILE *open_memstream(char **ptr, size_t *sizeloc);
···
 							 &tchart->tool);
 	int ret = -EINVAL;
 
-	if (session == NULL)
-		return -1;
+	if (IS_ERR(session))
+		return PTR_ERR(session);
 
 	symbol__init(&session->header.env);
 

tools/perf/builtin-top.c

···
 #include <linux/stringify.h>
 #include <linux/time64.h>
 #include <linux/types.h>
+#include <linux/err.h>
 
 #include <linux/ctype.h>
 
···
 	}
 
 	top.session = perf_session__new(NULL, false, NULL);
-	if (top.session == NULL) {
-		status = -1;
+	if (IS_ERR(top.session)) {
+		status = PTR_ERR(top.session);
 		goto out_delete_evlist;
 	}
 

tools/perf/builtin-trace.c

···
 	trace->multiple_threads = true;
 
 	session = perf_session__new(&data, false, &trace->tool);
-	if (session == NULL)
-		return -1;
+	if (IS_ERR(session))
+		return PTR_ERR(session);
 
 	if (trace->opts.target.pid)
 		symbol_conf.pid_list_str = strdup(trace->opts.target.pid);

tools/perf/tests/topology.c

···
 #include "session.h"
 #include "evlist.h"
 #include "debug.h"
+#include <linux/err.h>
 
 #define TEMPL "/tmp/perf-test-XXXXXX"
 #define DATA_SIZE	10
···
 	};
 
 	session = perf_session__new(&data, false, NULL);
-	TEST_ASSERT_VAL("can't get session", session);
+	TEST_ASSERT_VAL("can't get session", !IS_ERR(session));
 
 	session->evlist = perf_evlist__new_default();
 	TEST_ASSERT_VAL("can't get evlist", session->evlist);
···
 	int i;
 
 	session = perf_session__new(&data, false, NULL);
-	TEST_ASSERT_VAL("can't get session", session);
+	TEST_ASSERT_VAL("can't get session", !IS_ERR(session));
 
 	/* On platforms with large numbers of CPUs process_cpu_topology()
 	 * might issue an error while reading the perf.data file section

tools/perf/util/data-convert-bt.c

···
 #include "machine.h"
 #include "config.h"
 #include <linux/ctype.h>
+#include <linux/err.h>
 
 #define pr_N(n, fmt, ...) \
 	eprintf(n, debug_data_convert, fmt, ##__VA_ARGS__)
···
 	err = -1;
 	/* perf.data session */
 	session = perf_session__new(&data, 0, &c.tool);
-	if (!session)
+	if (IS_ERR(session)) {
+		err = PTR_ERR(session);
 		goto free_writer;
+	}
 
 	if (c.queue_size) {
 		ordered_events__set_alloc_size(&session->ordered_events,

tools/perf/util/session.c

···
 #include "../perf.h"
 #include "arch/common.h"
 #include <internal/lib.h>
+#include <linux/err.h>
 
 #ifdef HAVE_ZSTD_SUPPORT
 static int perf_session__process_compressed_event(struct perf_session *session,
···
 struct perf_session *perf_session__new(struct perf_data *data,
 				       bool repipe, struct perf_tool *tool)
 {
+	int ret = -ENOMEM;
 	struct perf_session *session = zalloc(sizeof(*session));
 
 	if (!session)
···
 
 	perf_env__init(&session->header.env);
 	if (data) {
-		if (perf_data__open(data))
+		ret = perf_data__open(data);
+		if (ret < 0)
 			goto out_delete;
 
 		session->data = data;
 
 		if (perf_data__is_read(data)) {
-			if (perf_session__open(session) < 0)
+			ret = perf_session__open(session);
+			if (ret < 0)
 				goto out_delete;
 
 			/*
···
 			perf_evlist__init_trace_event_sample_raw(session->evlist);
 
 			/* Open the directory data. */
-			if (data->is_dir && perf_data__open_dir(data))
+			if (data->is_dir) {
+				ret = perf_data__open_dir(data);
+			if (ret)
 				goto out_delete;
+			}
 		}
 	} else  {
 		session->machines.host.env = &perf_env;
···
  out_delete:
 	perf_session__delete(session);
  out:
-	return NULL;
+	return ERR_PTR(ret);
 }
 
 static void perf_session__delete_threads(struct perf_session *session)