perf probe: Dynamically allocate params memory

Avoid 14,432 bytes in .bss by dynamically allocating params.
Signed-off-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20230526183401.2326121-12-irogers@google.com
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ross Zwisler <zwisler@chromium.org>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-perf-users@vger.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-probe.c

@@ -47,29 +47,29 @@ static struct {
 	char *target;
 	struct strfilter *filter;
 	struct nsinfo *nsi;
-} params;
+} *params;
 
 /* Parse an event definition. Note that any error must die. */
 static int parse_probe_event(const char *str)
 {
-	struct perf_probe_event *pev = &params.events[params.nevents];
+	struct perf_probe_event *pev = &params->events[params->nevents];
 	int ret;
 
-	pr_debug("probe-definition(%d): %s\n", params.nevents, str);
-	if (++params.nevents == MAX_PROBES) {
+	pr_debug("probe-definition(%d): %s\n", params->nevents, str);
+	if (++params->nevents == MAX_PROBES) {
 		pr_err("Too many probes (> %d) were specified.", MAX_PROBES);
 		return -1;
 	}
 
-	pev->uprobes = params.uprobes;
-	if (params.target) {
-		pev->target = strdup(params.target);
+	pev->uprobes = params->uprobes;
+	if (params->target) {
+		pev->target = strdup(params->target);
 		if (!pev->target)
 			return -ENOMEM;
-		params.target_used = true;
+		params->target_used = true;
 	}
 
-	pev->nsi = nsinfo__get(params.nsi);
+	pev->nsi = nsinfo__get(params->nsi);
 
 	/* Parse a perf-probe command into event */
 	ret = parse_perf_probe_command(str, pev);
@@ -84,12 +84,12 @@ static int params_add_filter(const char *str)
 	int ret = 0;
 
 	pr_debug2("Add filter: %s\n", str);
-	if (!params.filter) {
-		params.filter = strfilter__new(str, &err);
-		if (!params.filter)
+	if (!params->filter) {
+		params->filter = strfilter__new(str, &err);
+		if (!params->filter)
 			ret = err ? -EINVAL : -ENOMEM;
 	} else
-		ret = strfilter__or(params.filter, str, &err);
+		ret = strfilter__or(params->filter, str, &err);
 
 	if (ret == -EINVAL) {
 		pr_err("Filter parse error at %td.\n", err - str + 1);
@@ -112,17 +112,17 @@ static int set_target(const char *ptr)
 	 * TODO: Support relative path, and $PATH, $LD_LIBRARY_PATH,
 	 * short module name.
 	 */
-	if (!params.target && ptr && *ptr == '/') {
-		params.target = strdup(ptr);
-		if (!params.target)
+	if (!params->target && ptr && *ptr == '/') {
+		params->target = strdup(ptr);
+		if (!params->target)
 			return -ENOMEM;
-		params.target_used = false;
+		params->target_used = false;
 
 		found = 1;
 		buf = ptr + (strlen(ptr) - 3);
 
 		if (strcmp(buf, ".ko"))
-			params.uprobes = true;
+			params->uprobes = true;
 
 	}
 
@@ -172,15 +172,15 @@ static int opt_set_target(const struct option *opt, const char *str,
 
 	if  (str) {
 		if (!strcmp(opt->long_name, "exec"))
-			params.uprobes = true;
+			params->uprobes = true;
 		else if (!strcmp(opt->long_name, "module"))
-			params.uprobes = false;
+			params->uprobes = false;
 		else
 			return ret;
 
 		/* Expand given path to absolute path, except for modulename */
-		if (params.uprobes || strchr(str, '/')) {
-			tmp = nsinfo__realpath(str, params.nsi);
+		if (params->uprobes || strchr(str, '/')) {
+			tmp = nsinfo__realpath(str, params->nsi);
 			if (!tmp) {
 				pr_warning("Failed to get the absolute path of %s: %m\n", str);
 				return ret;
@@ -190,9 +190,9 @@ static int opt_set_target(const struct option *opt, const char *str,
 			if (!tmp)
 				return -ENOMEM;
 		}
-		free(params.target);
-		params.target = tmp;
-		params.target_used = false;
+		free(params->target);
+		params->target = tmp;
+		params->target_used = false;
 		ret = 0;
 	}
 
@@ -217,7 +217,7 @@ static int opt_set_target_ns(const struct option *opt __maybe_unused,
 		}
 		nsip = nsinfo__new(ns_pid);
 		if (nsip && nsinfo__need_setns(nsip))
-			params.nsi = nsinfo__get(nsip);
+			params->nsi = nsinfo__get(nsip);
 		nsinfo__put(nsip);
 
 		ret = 0;
@@ -238,14 +238,14 @@ static int opt_show_lines(const struct option *opt,
 	if (!str)
 		return 0;
 
-	if (params.command == 'L') {
+	if (params->command == 'L') {
 		pr_warning("Warning: more than one --line options are"
 			   " detected. Only the first one is valid.\n");
 		return 0;
 	}
 
-	params.command = opt->short_name;
-	ret = parse_line_range_desc(str, &params.line_range);
+	params->command = opt->short_name;
+	ret = parse_line_range_desc(str, &params->line_range);
 
 	return ret;
 }
@@ -253,7 +253,7 @@ static int opt_show_lines(const struct option *opt,
 static int opt_show_vars(const struct option *opt,
 			 const char *str, int unset __maybe_unused)
 {
-	struct perf_probe_event *pev = &params.events[params.nevents];
+	struct perf_probe_event *pev = &params->events[params->nevents];
 	int ret;
 
 	if (!str)
@@ -264,7 +264,7 @@ static int opt_show_vars(const struct option *opt,
 		pr_err("  Error: '--vars' doesn't accept arguments.\n");
 		return -EINVAL;
 	}
-	params.command = opt->short_name;
+	params->command = opt->short_name;
 
 	return ret;
 }
@@ -276,7 +276,7 @@ static int opt_add_probe_event(const struct option *opt,
 			      const char *str, int unset __maybe_unused)
 {
 	if (str) {
-		params.command = opt->short_name;
+		params->command = opt->short_name;
 		return parse_probe_event(str);
 	}
 
@@ -287,7 +287,7 @@ static int opt_set_filter_with_command(const struct option *opt,
 				       const char *str, int unset)
 {
 	if (!unset)
-		params.command = opt->short_name;
+		params->command = opt->short_name;
 
 	if (str)
 		return params_add_filter(str);
@@ -306,20 +306,29 @@ static int opt_set_filter(const struct option *opt __maybe_unused,
 
 static int init_params(void)
 {
-	return line_range__init(&params.line_range);
+	int ret;
+
+	params = calloc(1, sizeof(*params));
+	if (!params)
+		return -ENOMEM;
+
+	ret = line_range__init(&params->line_range);
+	if (ret)
+		zfree(&params);
+	return ret;
 }
 
 static void cleanup_params(void)
 {
 	int i;
 
-	for (i = 0; i < params.nevents; i++)
-		clear_perf_probe_event(params.events + i);
-	line_range__clear(&params.line_range);
-	free(params.target);
-	strfilter__delete(params.filter);
-	nsinfo__put(params.nsi);
-	memset(&params, 0, sizeof(params));
+	for (i = 0; i < params->nevents; i++)
+		clear_perf_probe_event(params->events + i);
+	line_range__clear(&params->line_range);
+	free(params->target);
+	strfilter__delete(params->filter);
+	nsinfo__put(params->nsi);
+	zfree(&params);
 }
 
 static void pr_err_with_code(const char *msg, int err)
@@ -346,7 +355,7 @@ static int perf_add_probe_events(struct perf_probe_event *pevs, int npevs)
 	if (ret < 0)
 		goto out_cleanup;
 
-	if (params.command == 'D') {	/* it shows definition */
+	if (params->command == 'D') {	/* it shows definition */
 		if (probe_conf.bootconfig)
 			ret = show_bootconfig_events(pevs, npevs);
 		else
@@ -635,7 +644,7 @@ __cmd_probe(int argc, const char **argv)
 			usage_with_options_msg(probe_usage, options,
 				"'-' is not supported.\n");
 		}
-		if (params.command && params.command != 'a') {
+		if (params->command && params->command != 'a') {
 			usage_with_options_msg(probe_usage, options,
 				"another command except --add is set.\n");
 		}
@@ -644,7 +653,7 @@ __cmd_probe(int argc, const char **argv)
 			pr_err_with_code("  Error: Command Parse Error.", ret);
 			return ret;
 		}
-		params.command = 'a';
+		params->command = 'a';
 	}
 
 	ret = symbol__validate_sym_arguments();
@@ -664,54 +673,54 @@ __cmd_probe(int argc, const char **argv)
 	 * nor change running kernel. So if user gives offline vmlinux,
 	 * ignore its buildid.
 	 */
-	if (!strchr("lda", params.command) && symbol_conf.vmlinux_name)
+	if (!strchr("lda", params->command) && symbol_conf.vmlinux_name)
 		symbol_conf.ignore_vmlinux_buildid = true;
 
-	switch (params.command) {
+	switch (params->command) {
 	case 'l':
-		if (params.uprobes) {
+		if (params->uprobes) {
 			pr_err("  Error: Don't use --list with --exec.\n");
 			parse_options_usage(probe_usage, options, "l", true);
 			parse_options_usage(NULL, options, "x", true);
 			return -EINVAL;
 		}
-		ret = show_perf_probe_events(params.filter);
+		ret = show_perf_probe_events(params->filter);
 		if (ret < 0)
 			pr_err_with_code("  Error: Failed to show event list.", ret);
 		return ret;
 	case 'F':
-		ret = show_available_funcs(params.target, params.nsi,
-					   params.filter, params.uprobes);
+		ret = show_available_funcs(params->target, params->nsi,
+					   params->filter, params->uprobes);
 		if (ret < 0)
 			pr_err_with_code("  Error: Failed to show functions.", ret);
 		return ret;
 #ifdef HAVE_DWARF_SUPPORT
 	case 'L':
-		ret = show_line_range(&params.line_range, params.target,
-				      params.nsi, params.uprobes);
+		ret = show_line_range(&params->line_range, params->target,
+				      params->nsi, params->uprobes);
 		if (ret < 0)
 			pr_err_with_code("  Error: Failed to show lines.", ret);
 		return ret;
 	case 'V':
-		if (!params.filter)
-			params.filter = strfilter__new(DEFAULT_VAR_FILTER,
+		if (!params->filter)
+			params->filter = strfilter__new(DEFAULT_VAR_FILTER,
 						       NULL);
 
-		ret = show_available_vars(params.events, params.nevents,
-					  params.filter);
+		ret = show_available_vars(params->events, params->nevents,
+					  params->filter);
 		if (ret < 0)
 			pr_err_with_code("  Error: Failed to show vars.", ret);
 		return ret;
 #endif
 	case 'd':
-		ret = perf_del_probe_events(params.filter);
+		ret = perf_del_probe_events(params->filter);
 		if (ret < 0) {
 			pr_err_with_code("  Error: Failed to delete events.", ret);
 			return ret;
 		}
 		break;
 	case 'D':
-		if (probe_conf.bootconfig && params.uprobes) {
+		if (probe_conf.bootconfig && params->uprobes) {
 			pr_err("  Error: --bootconfig doesn't support uprobes.\n");
 			return -EINVAL;
 		}
@@ -719,25 +728,25 @@ __cmd_probe(int argc, const char **argv)
 	case 'a':
 
 		/* Ensure the last given target is used */
-		if (params.target && !params.target_used) {
+		if (params->target && !params->target_used) {
 			pr_err("  Error: -x/-m must follow the probe definitions.\n");
 			parse_options_usage(probe_usage, options, "m", true);
 			parse_options_usage(NULL, options, "x", true);
 			return -EINVAL;
 		}
 
-		ret = perf_add_probe_events(params.events, params.nevents);
+		ret = perf_add_probe_events(params->events, params->nevents);
 		if (ret < 0) {
 
 			/*
 			 * When perf_add_probe_events() fails it calls
 			 * cleanup_perf_probe_events(pevs, npevs), i.e.
-			 * cleanup_perf_probe_events(params.events, params.nevents), which
+			 * cleanup_perf_probe_events(params->events, params->nevents), which
 			 * will call clear_perf_probe_event(), so set nevents to zero
 			 * to avoid cleanup_params() to call clear_perf_probe_event() again
 			 * on the same pevs.
 			 */
-			params.nevents = 0;
+			params->nevents = 0;
 			pr_err_with_code("  Error: Failed to add events.", ret);
 			return ret;
 		}