diff options
| -rw-r--r-- | tools/perf/Documentation/perf-config.txt | 14 | ||||
| -rw-r--r-- | tools/perf/Documentation/perf-daemon.txt | 30 | ||||
| -rw-r--r-- | tools/perf/builtin-daemon.c | 351 |
3 files changed, 393 insertions, 2 deletions
diff --git a/tools/perf/Documentation/perf-config.txt b/tools/perf/Documentation/perf-config.txt index c3ce48f1b379..153bde14bbe0 100644 --- a/tools/perf/Documentation/perf-config.txt +++ b/tools/perf/Documentation/perf-config.txt @@ -703,6 +703,20 @@ auxtrace.*:: If the directory does not exist or has the wrong file type, the current directory is used. +daemon.*:: + + daemon.base:: + Base path for daemon data. All sessions data are stored under + this path. + +session-<NAME>.*:: + + session-<NAME>.run:: + + Defines new record session for daemon. The value is record's + command line without the 'record' keyword. + + SEE ALSO -------- linkperf:perf[1] diff --git a/tools/perf/Documentation/perf-daemon.txt b/tools/perf/Documentation/perf-daemon.txt index 1a4158cd973e..173b3f9f3a41 100644 --- a/tools/perf/Documentation/perf-daemon.txt +++ b/tools/perf/Documentation/perf-daemon.txt @@ -20,6 +20,20 @@ DESCRIPTION This command allows to run simple daemon process that starts and monitors configured record sessions. +You can imagine 'perf daemon' of background process with several +'perf record' child tasks, like: + + # ps axjf + ... + 1 916507 ... perf daemon start + 916507 916508 ... \_ perf record --control=fifo:control,ack -m 10M -e cycles --overwrite --switch-output -a + 916507 916509 ... \_ perf record --control=fifo:control,ack -m 20M -e sched:* --overwrite --switch-output -a + +Not every 'perf record' session is suitable for running under daemon. +User need perf session that either produces data on query, like the +flight recorder sessions in above example or session that is configured +to produce data periodically, like with --switch-output configuration +for time and size. OPTIONS ------- @@ -43,6 +57,22 @@ START COMMAND The start command creates the daemon process. +CONFIG FILE +----------- +The daemon is configured within standard perf config file by +following new variables: + +daemon.base: + Base path for daemon data. All sessions data are + stored under this path. + +session-<NAME>.run: + Defines new record session. The value is record's command + line without the 'record' keyword. + +Each perf record session is run in daemon.base/<NAME> directory. + + SEE ALSO -------- linkperf:perf-record[1], linkperf:perf-config[1] diff --git a/tools/perf/builtin-daemon.c b/tools/perf/builtin-daemon.c index 0a282c4e23a9..46f394f83361 100644 --- a/tools/perf/builtin-daemon.c +++ b/tools/perf/builtin-daemon.c @@ -2,6 +2,8 @@ #include <internal/lib.h> #include <subcmd/parse-options.h> #include <api/fd/array.h> +#include <linux/zalloc.h> +#include <linux/string.h> #include <linux/limits.h> #include <linux/string.h> #include <string.h> @@ -15,22 +17,74 @@ #include <sys/un.h> #include <sys/stat.h> #include <poll.h> +#include <sys/stat.h> #include "builtin.h" #include "perf.h" #include "debug.h" #include "config.h" #include "util.h" +#define SESSION_OUTPUT "output" + +/* + * Session states: + * + * OK - session is up and running + * RECONFIG - session is pending for reconfiguration, + * new values are already loaded in session object + * KILL - session is pending to be killed + * + * Session object life and its state is maintained by + * following functions: + * + * setup_server_config + * - reads config file and setup session objects + * with following states: + * + * OK - no change needed + * RECONFIG - session needs to be changed + * (run variable changed) + * KILL - session needs to be killed + * (session is no longer in config file) + * + * daemon__reconfig + * - scans session objects and does following actions + * for states: + * + * OK - skip + * RECONFIG - session is killed and re-run with new config + * KILL - session is killed + * + * - all sessions have OK state on the function exit + */ +enum daemon_session_state { + OK, + RECONFIG, + KILL, +}; + +struct daemon_session { + char *base; + char *name; + char *run; + int pid; + struct list_head list; + enum daemon_session_state state; +}; + struct daemon { const char *config; char *config_real; const char *base_user; char *base; + struct list_head sessions; FILE *out; char perf[PATH_MAX]; }; -static struct daemon __daemon = { }; +static struct daemon __daemon = { + .sessions = LIST_HEAD_INIT(__daemon.sessions), +}; static const char * const daemon_usage[] = { "perf daemon start [<options>]", @@ -45,6 +99,125 @@ static void sig_handler(int sig __maybe_unused) done = true; } +static struct daemon_session *daemon__add_session(struct daemon *config, char *name) +{ + struct daemon_session *session = zalloc(sizeof(*session)); + + if (!session) + return NULL; + + session->name = strdup(name); + if (!session->name) { + free(session); + return NULL; + } + + session->pid = -1; + list_add_tail(&session->list, &config->sessions); + return session; +} + +static struct daemon_session *daemon__find_session(struct daemon *daemon, char *name) +{ + struct daemon_session *session; + + list_for_each_entry(session, &daemon->sessions, list) { + if (!strcmp(session->name, name)) + return session; + } + + return NULL; +} + +static int get_session_name(const char *var, char *session, int len) +{ + const char *p = var + sizeof("session-") - 1; + + while (*p != '.' && *p != 0x0 && len--) + *session++ = *p++; + + *session = 0; + return *p == '.' ? 0 : -EINVAL; +} + +static int session_config(struct daemon *daemon, const char *var, const char *value) +{ + struct daemon_session *session; + char name[100]; + + if (get_session_name(var, name, sizeof(name))) + return -EINVAL; + + var = strchr(var, '.'); + if (!var) + return -EINVAL; + + var++; + + session = daemon__find_session(daemon, name); + + if (!session) { + /* New session is defined. */ + session = daemon__add_session(daemon, name); + if (!session) + return -ENOMEM; + + pr_debug("reconfig: found new session %s\n", name); + + /* Trigger reconfig to start it. */ + session->state = RECONFIG; + } else if (session->state == KILL) { + /* Current session is defined, no action needed. */ + pr_debug("reconfig: found current session %s\n", name); + session->state = OK; + } + + if (!strcmp(var, "run")) { + bool same = false; + + if (session->run) + same = !strcmp(session->run, value); + + if (!same) { + if (session->run) { + free(session->run); + pr_debug("reconfig: session %s is changed\n", name); + } + + session->run = strdup(value); + if (!session->run) + return -ENOMEM; + + /* + * Either new or changed run value is defined, + * trigger reconfig for the session. + */ + session->state = RECONFIG; + } + } + + return 0; +} + +static int server_config(const char *var, const char *value, void *cb) +{ + struct daemon *daemon = cb; + + if (strstarts(var, "session-")) { + return session_config(daemon, var, value); + } else if (!strcmp(var, "daemon.base") && !daemon->base_user) { + if (daemon->base && strcmp(daemon->base, value)) { + pr_err("failed: can't redefine base, bailing out\n"); + return -EINVAL; + } + daemon->base = strdup(value); + if (!daemon->base) + return -ENOMEM; + } + + return 0; +} + static int client_config(const char *var, const char *value, void *cb) { struct daemon *daemon = cb; @@ -106,6 +279,92 @@ static int setup_client_config(struct daemon *daemon) return err ?: check_base(daemon); } +static int setup_server_config(struct daemon *daemon) +{ + struct perf_config_set *set; + struct daemon_session *session; + int err = -ENOMEM; + + pr_debug("reconfig: started\n"); + + /* + * Mark all sessions for kill, the server config + * will set following states, see explanation at + * enum daemon_session_state declaration. + */ + list_for_each_entry(session, &daemon->sessions, list) + session->state = KILL; + + set = perf_config_set__load_file(daemon->config_real); + if (set) { + err = perf_config_set(set, server_config, daemon); + perf_config_set__delete(set); + } + + return err ?: check_base(daemon); +} + +static int daemon_session__run(struct daemon_session *session, + struct daemon *daemon) +{ + char buf[PATH_MAX]; + char **argv; + int argc, fd; + + if (asprintf(&session->base, "%s/session-%s", + daemon->base, session->name) < 0) { + perror("failed: asprintf"); + return -1; + } + + if (mkdir(session->base, 0755) && errno != EEXIST) { + perror("failed: mkdir"); + return -1; + } + + session->pid = fork(); + if (session->pid < 0) + return -1; + if (session->pid > 0) { + pr_info("reconfig: ruining session [%s:%d]: %s\n", + session->name, session->pid, session->run); + return 0; + } + + if (chdir(session->base)) { + perror("failed: chdir"); + return -1; + } + + fd = open("/dev/null", O_RDONLY); + if (fd < 0) { + perror("failed: open /dev/null"); + return -1; + } + + dup2(fd, 0); + close(fd); + + fd = open(SESSION_OUTPUT, O_RDWR|O_CREAT|O_TRUNC, 0644); + if (fd < 0) { + perror("failed: open session output"); + return -1; + } + + dup2(fd, 1); + dup2(fd, 2); + close(fd); + + scnprintf(buf, sizeof(buf), "%s record %s", daemon->perf, session->run); + + argv = argv_split(buf, &argc); + if (!argv) + exit(-1); + + exit(execve(daemon->perf, argv, NULL)); + return -1; +} + static int setup_server_socket(struct daemon *daemon) { struct sockaddr_un addr; @@ -224,12 +483,89 @@ static int setup_client_socket(struct daemon *daemon) return fd; } +static int daemon_session__signal(struct daemon_session *session, int sig) +{ + if (session->pid < 0) + return -1; + return kill(session->pid, sig); +} + +static void daemon_session__kill(struct daemon_session *session) +{ + daemon_session__signal(session, SIGTERM); +} + +static void daemon__signal(struct daemon *daemon, int sig) +{ + struct daemon_session *session; + + list_for_each_entry(session, &daemon->sessions, list) + daemon_session__signal(session, sig); +} + +static void daemon_session__delete(struct daemon_session *session) +{ + free(session->base); + free(session->name); + free(session->run); + free(session); +} + +static void daemon_session__remove(struct daemon_session *session) +{ + list_del(&session->list); + daemon_session__delete(session); +} + +static void daemon__kill(struct daemon *daemon) +{ + daemon__signal(daemon, SIGTERM); +} + static void daemon__exit(struct daemon *daemon) { + struct daemon_session *session, *h; + + list_for_each_entry_safe(session, h, &daemon->sessions, list) + daemon_session__remove(session); + free(daemon->config_real); free(daemon->base); } +static int daemon__reconfig(struct daemon *daemon) +{ + struct daemon_session *session, *n; + + list_for_each_entry_safe(session, n, &daemon->sessions, list) { + /* No change. */ + if (session->state == OK) + continue; + + /* Remove session. */ + if (session->state == KILL) { + if (session->pid > 0) { + daemon_session__kill(session); + pr_info("reconfig: session '%s' killed\n", session->name); + } + daemon_session__remove(session); + continue; + } + + /* Reconfig session. */ + if (session->pid > 0) { + daemon_session__kill(session); + pr_info("reconfig: session '%s' killed\n", session->name); + } + if (daemon_session__run(session, daemon)) + return -1; + + session->state = OK; + } + + return 0; +} + static int setup_config(struct daemon *daemon) { if (daemon->base_user) { @@ -278,6 +614,9 @@ static int __cmd_start(struct daemon *daemon, struct option parent_options[], return -1; } + if (setup_server_config(daemon)) + return -1; + debug_set_file(daemon->out); debug_set_display_time(true); @@ -297,15 +636,23 @@ static int __cmd_start(struct daemon *daemon, struct option parent_options[], signal(SIGTERM, sig_handler); while (!done && !err) { - if (fdarray__poll(&fda, -1)) { + err = daemon__reconfig(daemon); + + if (!err && fdarray__poll(&fda, -1)) { + bool reconfig = false; + if (fda.entries[sock_pos].revents & POLLIN) err = handle_server_socket(daemon, sock_fd); + + if (reconfig) + err = setup_server_config(daemon); } } out: fdarray__exit(&fda); + daemon__kill(daemon); daemon__exit(daemon); if (sock_fd != -1) |