perf tools: Allow specifying proc-map-timeout in config file

The default timeout of 500ms for parsing /proc/<pid>/maps files is too
short for profiling many of our services.

This can be overridden by passing --proc-map-timeout to the relevant
command but it'd be nice to globally increase our default value.

This patch permits setting a different default with the
core.proc-map-timeout config file parameter.

Signed-off-by: Mark Drayton <[e-mail]>
Acked-by: Song Liu <[e-mail]>
Acked-by: Namhyung Kim <[e-mail]>
Cc: Alexander Shishkin <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/Documentation/perf-config.txt

···
 		Colors for headers in the output of a sub-commands (top, report).
 		Default values are 'white', 'blue'.
 
+core.*::
+	core.proc-map-timeout::
+		Sets a timeout (in milliseconds) for parsing /proc/<pid>/maps files.
+		Can be overridden by the --proc-map-timeout option on supported
+		subcommands. The default timeout is 500ms.
+
 tui.*, gtk.*::
 	Subcommands that can be configured here are 'top', 'report' and 'annotate'.
 	These values are booleans, for example:

tools/perf/builtin-kvm.c

···
 			"show events other than"
 			" HLT (x86 only) or Wait state (s390 only)"
 			" that take longer than duration usecs"),
-		OPT_UINTEGER(0, "proc-map-timeout", &kvm->opts.proc_map_timeout,
+		OPT_UINTEGER(0, "proc-map-timeout", &proc_map_timeout,
 				"per thread proc mmap processing timeout in ms"),
 		OPT_END()
 	};
···
 	kvm->opts.target.uses_mmap = false;
 	kvm->opts.target.uid_str = NULL;
 	kvm->opts.target.uid = UINT_MAX;
-	kvm->opts.proc_map_timeout = 500;
 
 	symbol__init(NULL);
 	disable_buildid_cache();
···
 	perf_session__set_id_hdr_size(kvm->session);
 	ordered_events__set_copy_on_queue(&kvm->session->ordered_events, true);
 	machine__synthesize_threads(&kvm->session->machines.host, &kvm->opts.target,
-				    kvm->evlist->threads, false,
-				    kvm->opts.proc_map_timeout, 1);
+				    kvm->evlist->threads, false, 1);
 	err = kvm_live_open_events(kvm);
 	if (err)
 		goto out;

tools/perf/builtin-record.c

···
 	err = perf_event__synthesize_thread_map(&rec->tool, thread_map,
 						 process_synthesized_event,
 						 &rec->session->machines.host,
-						 rec->opts.sample_address,
-						 rec->opts.proc_map_timeout);
+						 rec->opts.sample_address);
 	thread_map__put(thread_map);
 	return err;
 }
···
 
 	err = __machine__synthesize_threads(machine, tool, &opts->target, rec->evlist->threads,
 					    process_synthesized_event, opts->sample_address,
-					    opts->proc_map_timeout, 1);
+					    1);
 out:
 	return err;
 }
···
 			.uses_mmap   = true,
 			.default_per_cpu = true,
 		},
-		.proc_map_timeout     = 500,
 	},
 	.tool = {
 		.sample		= process_sample_event,
···
 	parse_clockid),
 	OPT_STRING_OPTARG('S', "snapshot", &record.opts.auxtrace_snapshot_opts,
 			  "opts", "AUX area tracing Snapshot Mode", ""),
-	OPT_UINTEGER(0, "proc-map-timeout", &record.opts.proc_map_timeout,
+	OPT_UINTEGER(0, "proc-map-timeout", &proc_map_timeout,
 			"per thread proc mmap processing timeout in ms"),
 	OPT_BOOLEAN(0, "namespaces", &record.opts.record_namespaces,
 		    "Record namespaces events"),

tools/perf/builtin-top.c

···
 
 	machine__synthesize_threads(&top->session->machines.host, &opts->target,
 				    top->evlist->threads, false,
-				    opts->proc_map_timeout,
 				    top->nr_threads_synthesize);
 
 	if (top->nr_threads_synthesize > 1)
···
 			.target		= {
 				.uses_mmap   = true,
 			},
-			.proc_map_timeout    = 500,
 			/*
 			 * FIXME: This will lose PERF_RECORD_MMAP and other metadata
 			 * when we pause, fix that and reenable. Probably using a
···
 	OPT_STRING('w', "column-widths", &symbol_conf.col_width_list_str,
 		   "width[,width...]",
 		   "don't try to adjust column width, use these fixed values"),
-	OPT_UINTEGER(0, "proc-map-timeout", &opts->proc_map_timeout,
+	OPT_UINTEGER(0, "proc-map-timeout", &proc_map_timeout,
 			"per thread proc mmap processing timeout in ms"),
 	OPT_CALLBACK_NOOPT('b', "branch-any", &opts->branch_stack,
 		     "branch any", "sample any taken branches",

tools/perf/builtin-trace.c

···
 
 	err = __machine__synthesize_threads(trace->host, &trace->tool, &trace->opts.target,
 					    evlist->threads, trace__tool_process, false,
-					    trace->opts.proc_map_timeout, 1);
+					    1);
 out:
 	if (err)
 		symbol__exit();
···
 			.user_interval = ULLONG_MAX,
 			.no_buffering  = true,
 			.mmap_pages    = UINT_MAX,
-			.proc_map_timeout  = 500,
 		},
 		.output = stderr,
 		.show_comm = true,
···
 		     "Default: kernel.perf_event_max_stack or " __stringify(PERF_MAX_STACK_DEPTH)),
 	OPT_BOOLEAN(0, "print-sample", &trace.print_sample,
 			"print the PERF_RECORD_SAMPLE PERF_SAMPLE_ info, for debugging"),
-	OPT_UINTEGER(0, "proc-map-timeout", &trace.opts.proc_map_timeout,
+	OPT_UINTEGER(0, "proc-map-timeout", &proc_map_timeout,
 			"per thread proc mmap processing timeout in ms"),
 	OPT_CALLBACK('G', "cgroup", &trace, "name", "monitor event in cgroup name only",
 		     trace__parse_cgroups),

tools/perf/perf.h

···
 	bool         use_clockid;
 	clockid_t    clockid;
 	u64          clockid_res_ns;
-	unsigned int proc_map_timeout;
 	int	     nr_cblocks;
 };
 

tools/perf/tests/code-reading.c

···
 	}
 
 	ret = perf_event__synthesize_thread_map(NULL, threads,
-						perf_event__process, machine, false, 500);
+						perf_event__process, machine, false);
 	if (ret < 0) {
 		pr_debug("perf_event__synthesize_thread_map failed\n");
 		goto out_err;

tools/perf/tests/dwarf-unwind.c

···
 	pid_t pid = getpid();
 
 	return perf_event__synthesize_mmap_events(NULL, &event, pid, pid,
-						  mmap_handler, machine, true, 500);
+						  mmap_handler, machine, true);
 }
 
 /*

tools/perf/tests/mmap-thread-lookup.c

···
 {
 	return perf_event__synthesize_threads(NULL,
 					      perf_event__process,
-					      machine, 0, 500, 1);
+					      machine, 0, 1);
 }
 
 static int synth_process(struct machine *machine)
···
 
 	err = perf_event__synthesize_thread_map(NULL, map,
 						perf_event__process,
-						machine, 0, 500);
+						machine, 0);
 
 	thread_map__put(map);
 	return err;

tools/perf/util/config.c

···
 #include "util.h"
 #include "cache.h"
 #include <subcmd/exec-cmd.h>
+#include "util/event.h"  /* proc_map_timeout */
 #include "util/hist.h"  /* perf_hist_config */
 #include "util/llvm-utils.h"   /* perf_llvm_config */
 #include "config.h"
···
 static int perf_default_core_config(const char *var __maybe_unused,
 				    const char *value __maybe_unused)
 {
+	if (!strcmp(var, "core.proc-map-timeout"))
+		proc_map_timeout = strtoul(value, NULL, 10);
+
 	/* Add other config variables here. */
 	return 0;
 }

tools/perf/util/event.c

···
 #include "asm/bug.h"
 #include "stat.h"
 
+#define DEFAULT_PROC_MAP_PARSE_TIMEOUT 500
+
 static const char *perf_event__names[] = {
 	[0]					= "TOTAL",
 	[PERF_RECORD_MMAP]			= "MMAP",
···
 	[MNT_NS_INDEX]		= "mnt",
 	[CGROUP_NS_INDEX]	= "cgroup",
 };
+
+unsigned int proc_map_timeout = DEFAULT_PROC_MAP_PARSE_TIMEOUT;
 
 const char *perf_event__name(unsigned int id)
 {
···
 				       pid_t pid, pid_t tgid,
 				       perf_event__handler_t process,
 				       struct machine *machine,
-				       bool mmap_data,
-				       unsigned int proc_map_timeout)
+				       bool mmap_data)
 {
 	char filename[PATH_MAX];
 	FILE *fp;
···
 				      perf_event__handler_t process,
 				      struct perf_tool *tool,
 				      struct machine *machine,
-				      bool mmap_data,
-				      unsigned int proc_map_timeout)
+				      bool mmap_data)
 {
 	char filename[PATH_MAX];
 	DIR *tasks;
···
 		 */
 		if (pid == tgid &&
 		    perf_event__synthesize_mmap_events(tool, mmap_event, pid, tgid,
-						       process, machine, mmap_data,
-						       proc_map_timeout))
+						       process, machine, mmap_data))
 			return -1;
 
 		return 0;
···
 		if (_pid == pid) {
 			/* process the parent's maps too */
 			rc = perf_event__synthesize_mmap_events(tool, mmap_event, pid, tgid,
-						process, machine, mmap_data, proc_map_timeout);
+						process, machine, mmap_data);
 			if (rc)
 				break;
 		}
···
 				      struct thread_map *threads,
 				      perf_event__handler_t process,
 				      struct machine *machine,
-				      bool mmap_data,
-				      unsigned int proc_map_timeout)
+				      bool mmap_data)
 {
 	union perf_event *comm_event, *mmap_event, *fork_event;
 	union perf_event *namespaces_event;
···
 					       fork_event, namespaces_event,
 					       thread_map__pid(threads, thread), 0,
 					       process, tool, machine,
-					       mmap_data, proc_map_timeout)) {
+					       mmap_data)) {
 			err = -1;
 			break;
 		}
···
 						       fork_event, namespaces_event,
 						       comm_event->comm.pid, 0,
 						       process, tool, machine,
-						       mmap_data, proc_map_timeout)) {
+						       mmap_data)) {
 				err = -1;
 				break;
 			}
···
 					    perf_event__handler_t process,
 					    struct machine *machine,
 					    bool mmap_data,
-					    unsigned int proc_map_timeout,
 					    struct dirent **dirent,
 					    int start,
 					    int num)
···
 		 */
 		__event__synthesize_thread(comm_event, mmap_event, fork_event,
 					   namespaces_event, pid, 1, process,
-					   tool, machine, mmap_data,
-					   proc_map_timeout);
+					   tool, machine, mmap_data);
 	}
 	err = 0;
 
···
 	perf_event__handler_t process;
 	struct machine *machine;
 	bool mmap_data;
-	unsigned int proc_map_timeout;
 	struct dirent **dirent;
 	int num;
 	int start;
···
 
 	__perf_event__synthesize_threads(args->tool, args->process,
 					 args->machine, args->mmap_data,
-					 args->proc_map_timeout, args->dirent,
+					 args->dirent,
 					 args->start, args->num);
 	return NULL;
 }
···
 				   perf_event__handler_t process,
 				   struct machine *machine,
 				   bool mmap_data,
-				   unsigned int proc_map_timeout,
 				   unsigned int nr_threads_synthesize)
 {
 	struct synthesize_threads_arg *args = NULL;
···
 	if (thread_nr <= 1) {
 		err = __perf_event__synthesize_threads(tool, process,
 						       machine, mmap_data,
-						       proc_map_timeout,
 						       dirent, base, n);
 		goto free_dirent;
 	}
···
 		args[i].process = process;
 		args[i].machine = machine;
 		args[i].mmap_data = mmap_data;
-		args[i].proc_map_timeout = proc_map_timeout;
 		args[i].dirent = dirent;
 	}
 	for (i = 0; i < m; i++) {

tools/perf/util/event.h

···
 int perf_event__synthesize_thread_map(struct perf_tool *tool,
 				      struct thread_map *threads,
 				      perf_event__handler_t process,
-				      struct machine *machine, bool mmap_data,
-				      unsigned int proc_map_timeout);
+				      struct machine *machine, bool mmap_data);
 int perf_event__synthesize_thread_map2(struct perf_tool *tool,
 				      struct thread_map *threads,
 				      perf_event__handler_t process,
···
 int perf_event__synthesize_threads(struct perf_tool *tool,
 				   perf_event__handler_t process,
 				   struct machine *machine, bool mmap_data,
-				   unsigned int proc_map_timeout,
 				   unsigned int nr_threads_synthesize);
 int perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
 				       perf_event__handler_t process,
···
 				       pid_t pid, pid_t tgid,
 				       perf_event__handler_t process,
 				       struct machine *machine,
-				       bool mmap_data,
-				       unsigned int proc_map_timeout);
+				       bool mmap_data);
 
 int perf_event__synthesize_extra_kmaps(struct perf_tool *tool,
 				       perf_event__handler_t process,
···
 
 extern int sysctl_perf_event_max_stack;
 extern int sysctl_perf_event_max_contexts_per_stack;
+extern unsigned int proc_map_timeout;
 
 #endif /* __PERF_RECORD_H */

tools/perf/util/machine.c

···
 int __machine__synthesize_threads(struct machine *machine, struct perf_tool *tool,
 				  struct target *target, struct thread_map *threads,
 				  perf_event__handler_t process, bool data_mmap,
-				  unsigned int proc_map_timeout,
 				  unsigned int nr_threads_synthesize)
 {
 	if (target__has_task(target))
-		return perf_event__synthesize_thread_map(tool, threads, process, machine, data_mmap, proc_map_timeout);
+		return perf_event__synthesize_thread_map(tool, threads, process, machine, data_mmap);
 	else if (target__has_cpu(target))
 		return perf_event__synthesize_threads(tool, process,
 						      machine, data_mmap,
-						      proc_map_timeout,
 						      nr_threads_synthesize);
 	/* command specified */
 	return 0;

tools/perf/util/machine.h

···
 int __machine__synthesize_threads(struct machine *machine, struct perf_tool *tool,
 				  struct target *target, struct thread_map *threads,
 				  perf_event__handler_t process, bool data_mmap,
-				  unsigned int proc_map_timeout,
 				  unsigned int nr_threads_synthesize);
 static inline
 int machine__synthesize_threads(struct machine *machine, struct target *target,
 				struct thread_map *threads, bool data_mmap,
-				unsigned int proc_map_timeout,
 				unsigned int nr_threads_synthesize)
 {
 	return __machine__synthesize_threads(machine, NULL, target, threads,
 					     perf_event__process, data_mmap,
-					     proc_map_timeout,
 					     nr_threads_synthesize);
 }