X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lib%2Fvlog.c;h=b1ca15895db5dd033ed72956ef75f34bffd30dcc;hb=0141e875a14cc30fe9c207a83616861055531d4d;hp=2587cdeda01e0356a79bc49c9d4d16b1c33b2fa7;hpb=7106bb5e7be0db6ca67c61a5fcb66fac2735c42c;p=sliver-openvswitch.git diff --git a/lib/vlog.c b/lib/vlog.c index 2587cdeda..b1ca15895 100644 --- a/lib/vlog.c +++ b/lib/vlog.c @@ -28,30 +28,34 @@ #include #include #include +#include "async-append.h" #include "coverage.h" #include "dirs.h" #include "dynamic-string.h" #include "ofpbuf.h" +#include "ovs-thread.h" #include "sat-math.h" #include "svec.h" #include "timeval.h" #include "unixctl.h" #include "util.h" -#include "worker.h" VLOG_DEFINE_THIS_MODULE(vlog); -COVERAGE_DEFINE(vlog_recursive); +/* ovs_assert() logs the assertion message, so using ovs_assert() in this + * source file could cause recursion. */ +#undef ovs_assert +#define ovs_assert use_assert_instead_of_ovs_assert_in_this_module /* Name for each logging level. */ -static const char *level_names[VLL_N_LEVELS] = { +static const char *const level_names[VLL_N_LEVELS] = { #define VLOG_LEVEL(NAME, SYSLOG_LEVEL) #NAME, VLOG_LEVELS #undef VLOG_LEVEL }; /* Syslog value for each logging level. */ -static int syslog_levels[VLL_N_LEVELS] = { +static const int syslog_levels[VLL_N_LEVELS] = { #define VLOG_LEVEL(NAME, SYSLOG_LEVEL) SYSLOG_LEVEL, VLOG_LEVELS #undef VLOG_LEVEL @@ -68,6 +72,7 @@ extern struct vlog_module *__stop_vlog_modules[]; #include "vlog-modules.def" #undef VLOG_MODULE +extern struct vlog_module *vlog_modules[]; struct vlog_module *vlog_modules[] = { #define VLOG_MODULE(NAME) &VLM_##NAME, #include "vlog-modules.def" @@ -76,10 +81,15 @@ struct vlog_module *vlog_modules[] = { #define n_vlog_modules ARRAY_SIZE(vlog_modules) #endif +/* Protects the 'pattern' in all "struct facility"s, so that a race between + * changing and reading the pattern does not cause an access to freed + * memory. */ +static struct ovs_rwlock pattern_rwlock = OVS_RWLOCK_INITIALIZER; + /* Information about each facility. */ struct facility { const char *name; /* Name. */ - char *pattern; /* Current pattern. */ + char *pattern OVS_GUARDED_BY(pattern_rwlock); /* Current pattern. */ bool default_pattern; /* Whether current pattern is the default. */ }; static struct facility facilities[VLF_N_FACILITIES] = { @@ -88,24 +98,28 @@ static struct facility facilities[VLF_N_FACILITIES] = { #undef VLOG_FACILITY }; -/* VLF_FILE configuration. */ -static char *log_file_name; -static int log_fd = -1; +/* Sequence number for the message currently being composed. */ +DEFINE_STATIC_PER_THREAD_DATA(unsigned int, msg_num, 0); -/* vlog initialized? */ -static bool vlog_inited; +/* VLF_FILE configuration. + * + * All of the following is protected by 'log_file_mutex', which nests inside + * pattern_rwlock. */ +static struct ovs_mutex log_file_mutex = OVS_MUTEX_INITIALIZER; +static char *log_file_name OVS_GUARDED_BY(log_file_mutex); +static int log_fd OVS_GUARDED_BY(log_file_mutex) = -1; +static struct async_append *log_writer OVS_GUARDED_BY(log_file_mutex); +static bool log_async OVS_GUARDED_BY(log_file_mutex); static void format_log_message(const struct vlog_module *, enum vlog_level, - enum vlog_facility, unsigned int msg_num, + enum vlog_facility, const char *message, va_list, struct ds *) - PRINTF_FORMAT(5, 0); -static void vlog_write_file(struct ds *); -static void vlog_update_async_log_fd(void); + PRINTF_FORMAT(4, 0) OVS_REQ_RDLOCK(&pattern_rwlock); /* Searches the 'n_names' in 'names'. Returns the index of a match for * 'target', or 'n_names' if no name matches. */ static size_t -search_name_array(const char *target, const char **names, size_t n_names) +search_name_array(const char *target, const char *const *names, size_t n_names) { size_t i; @@ -188,7 +202,7 @@ vlog_get_level(const struct vlog_module *module, enum vlog_facility facility) } static void -update_min_level(struct vlog_module *module) +update_min_level(struct vlog_module *module) OVS_REQUIRES(&log_file_mutex) { enum vlog_facility facility; @@ -210,6 +224,7 @@ set_facility_level(enum vlog_facility facility, struct vlog_module *module, assert(facility >= 0 && facility < VLF_N_FACILITIES); assert(level < VLL_N_LEVELS); + ovs_mutex_lock(&log_file_mutex); if (!module) { struct vlog_module **mp; @@ -221,6 +236,7 @@ set_facility_level(enum vlog_facility facility, struct vlog_module *module, module->levels[facility] = level; update_min_level(module); } + ovs_mutex_unlock(&log_file_mutex); } /* Sets the logging level for the given 'module' and 'facility' to 'level'. A @@ -244,12 +260,15 @@ static void do_set_pattern(enum vlog_facility facility, const char *pattern) { struct facility *f = &facilities[facility]; + + ovs_rwlock_wrlock(&pattern_rwlock); if (!f->default_pattern) { free(f->pattern); } else { f->default_pattern = false; } f->pattern = xstrdup(pattern); + ovs_rwlock_unlock(&pattern_rwlock); } /* Sets the pattern for the given 'facility' to 'pattern'. */ @@ -266,63 +285,79 @@ vlog_set_pattern(enum vlog_facility facility, const char *pattern) } } -/* Returns the name of the log file used by VLF_FILE, or a null pointer if no - * log file has been set. (A non-null return value does not assert that the - * named log file is in use: if vlog_set_log_file() or vlog_reopen_log_file() - * fails, it still sets the log file name.) */ -const char * -vlog_get_log_file(void) -{ - return log_file_name; -} - /* Sets the name of the log file used by VLF_FILE to 'file_name', or to the * default file name if 'file_name' is null. Returns 0 if successful, * otherwise a positive errno value. */ int vlog_set_log_file(const char *file_name) { - char *old_log_file_name; + char *new_log_file_name; struct vlog_module **mp; - int error; + struct stat old_stat; + struct stat new_stat; + int new_log_fd; + bool same_file; + bool log_close; + + /* Open new log file. */ + new_log_file_name = (file_name + ? xstrdup(file_name) + : xasprintf("%s/%s.log", ovs_logdir(), program_name)); + new_log_fd = open(new_log_file_name, O_WRONLY | O_CREAT | O_APPEND, 0666); + if (new_log_fd < 0) { + VLOG_WARN("failed to open %s for logging: %s", + new_log_file_name, ovs_strerror(errno)); + free(new_log_file_name); + return errno; + } + + /* If the new log file is the same one we already have open, bail out. */ + ovs_mutex_lock(&log_file_mutex); + same_file = (log_fd >= 0 + && new_log_fd >= 0 + && !fstat(log_fd, &old_stat) + && !fstat(new_log_fd, &new_stat) + && old_stat.st_dev == new_stat.st_dev + && old_stat.st_ino == new_stat.st_ino); + ovs_mutex_unlock(&log_file_mutex); + if (same_file) { + close(new_log_fd); + free(new_log_file_name); + return 0; + } - /* Close old log file. */ - if (log_fd >= 0) { + /* Log closing old log file (we can't log while holding log_file_mutex). */ + ovs_mutex_lock(&log_file_mutex); + log_close = log_fd >= 0; + ovs_mutex_unlock(&log_file_mutex); + if (log_close) { VLOG_INFO("closing log file"); - close(log_fd); - log_fd = -1; } - /* Update log file name and free old name. The ordering is important - * because 'file_name' might be 'log_file_name' or some suffix of it. */ - old_log_file_name = log_file_name; - log_file_name = (file_name - ? xstrdup(file_name) - : xasprintf("%s/%s.log", ovs_logdir(), program_name)); - free(old_log_file_name); - file_name = NULL; /* Might have been freed. */ - - /* Open new log file and update min_levels[] to reflect whether we actually - * have a log_file. */ - log_fd = open(log_file_name, O_WRONLY | O_CREAT | O_APPEND, 0666); + /* Close old log file, if any, and install new one. */ + ovs_mutex_lock(&log_file_mutex); if (log_fd >= 0) { - vlog_update_async_log_fd(); + free(log_file_name); + close(log_fd); + async_append_destroy(log_writer); + } + + log_file_name = xstrdup(new_log_file_name); + log_fd = new_log_fd; + if (log_async) { + log_writer = async_append_create(new_log_fd); } + for (mp = vlog_modules; mp < &vlog_modules[n_vlog_modules]; mp++) { update_min_level(*mp); } + ovs_mutex_unlock(&log_file_mutex); - /* Log success or failure. */ - if (log_fd < 0) { - VLOG_WARN("failed to open %s for logging: %s", - log_file_name, strerror(errno)); - error = errno; - } else { - VLOG_INFO("opened log file %s", log_file_name); - error = 0; - } + /* Log opening new log file (we can't log while holding log_file_mutex). */ + VLOG_INFO("opened log file %s", new_log_file_name); + free(new_log_file_name); - return error; + return 0; } /* Closes and then attempts to re-open the current log file. (This is useful @@ -331,25 +366,19 @@ vlog_set_log_file(const char *file_name) int vlog_reopen_log_file(void) { - struct stat old, new; + char *fn; - /* Skip re-opening if there's nothing to reopen. */ - if (!log_file_name) { - return 0; - } + ovs_mutex_lock(&log_file_mutex); + fn = log_file_name ? xstrdup(log_file_name) : NULL; + ovs_mutex_unlock(&log_file_mutex); - /* Skip re-opening if it would be a no-op because the old and new files are - * the same. (This avoids writing "closing log file" followed immediately - * by "opened log file".) */ - if (log_fd >= 0 - && !fstat(log_fd, &old) - && !stat(log_file_name, &new) - && old.st_dev == new.st_dev - && old.st_ino == new.st_ino) { + if (fn) { + int error = vlog_set_log_file(fn); + free(fn); + return error; + } else { return 0; } - - return vlog_set_log_file(log_file_name); } /* Set debugging levels. Returns null if successful, otherwise an error @@ -426,6 +455,16 @@ exit: return msg; } +/* Set debugging levels. Abort with an error message if 's' is invalid. */ +void +vlog_set_levels_from_string_assert(const char *s) +{ + char *error = vlog_set_levels_from_string(s); + if (error) { + ovs_fatal(0, "%s", error); + } +} + /* If 'arg' is null, configure maximum verbosity. Otherwise, sets * configuration according to 'arg' (see vlog_set_levels_from_string()). */ void @@ -471,10 +510,16 @@ static void vlog_unixctl_reopen(struct unixctl_conn *conn, int argc OVS_UNUSED, const char *argv[] OVS_UNUSED, void *aux OVS_UNUSED) { - if (log_file_name) { + bool has_log_file; + + ovs_mutex_lock(&log_file_mutex); + has_log_file = log_file_name != NULL; + ovs_mutex_unlock(&log_file_mutex); + + if (has_log_file) { int error = vlog_reopen_log_file(); if (error) { - unixctl_command_reply_error(conn, strerror(errno)); + unixctl_command_reply_error(conn, ovs_strerror(errno)); } else { unixctl_command_reply(conn, NULL); } @@ -532,18 +577,11 @@ vlog_disable_rate_limit(struct unixctl_conn *conn, int argc, set_rate_limits(conn, argc, argv, false); } -/* Initializes the logging subsystem and registers its unixctl server - * commands. */ -void -vlog_init(void) +static void +vlog_init__(void) { static char *program_name_copy; - time_t now; - - if (vlog_inited) { - return; - } - vlog_inited = true; + long long int now; /* openlog() is allowed to keep the pointer passed in, without making a * copy. The daemonize code sometimes frees and replaces 'program_name', @@ -553,14 +591,11 @@ vlog_init(void) program_name_copy = program_name ? xstrdup(program_name) : NULL; openlog(program_name_copy, LOG_NDELAY, LOG_DAEMON); - now = time_wall(); + now = time_wall_msec(); if (now < 0) { - struct tm tm; - char s[128]; - - gmtime_r(&now, &tm); - strftime(s, sizeof s, "%a, %d %b %Y %H:%M:%S", &tm); - VLOG_ERR("current time is negative: %s (%ld)", s, (long int) now); + char *s = xastrftime_msec("%a, %d %b %Y %H:%M:%S", now, true); + VLOG_ERR("current time is negative: %s (%lld)", s, now); + free(s); } unixctl_command_register( @@ -575,14 +610,29 @@ vlog_init(void) vlog_unixctl_reopen, NULL); } -/* Closes the logging subsystem. */ +/* Initializes the logging subsystem and registers its unixctl server + * commands. */ +void +vlog_init(void) +{ + static pthread_once_t once = PTHREAD_ONCE_INIT; + pthread_once(&once, vlog_init__); +} + +/* Enables VLF_FILE log output to be written asynchronously to disk. + * Asynchronous file writes avoid blocking the process in the case of a busy + * disk, but on the other hand they are less robust: there is a chance that the + * write will not make it to the log file if the process crashes soon after the + * log call. */ void -vlog_exit(void) +vlog_enable_async(void) { - if (vlog_inited) { - closelog(); - vlog_inited = false; + ovs_mutex_lock(&log_file_mutex); + log_async = true; + if (log_fd >= 0 && !log_writer) { + log_writer = async_append_create(log_fd); } + ovs_mutex_unlock(&log_file_mutex); } /* Print the current logging level for each module. */ @@ -650,7 +700,7 @@ fetch_braces(const char *p, const char *def, char *out, size_t out_size) static void format_log_message(const struct vlog_module *module, enum vlog_level level, - enum vlog_facility facility, unsigned int msg_num, + enum vlog_facility facility, const char *message, va_list args_, struct ds *s) { char tmp[128]; @@ -659,6 +709,7 @@ format_log_message(const struct vlog_module *module, enum vlog_level level, ds_clear(s); for (p = facilities[facility].pattern; *p != '\0'; ) { + const char *subprogram_name; enum { LEFT, RIGHT } justify = RIGHT; int pad = '0'; size_t length, field, used; @@ -693,12 +744,12 @@ format_log_message(const struct vlog_module *module, enum vlog_level level, ds_put_cstr(s, vlog_get_module_name(module)); break; case 'd': - p = fetch_braces(p, "%Y-%m-%d %H:%M:%S", tmp, sizeof tmp); - ds_put_strftime(s, tmp, false); + p = fetch_braces(p, "%Y-%m-%d %H:%M:%S.###", tmp, sizeof tmp); + ds_put_strftime_msec(s, tmp, time_wall_msec(), false); break; case 'D': - p = fetch_braces(p, "%Y-%m-%d %H:%M:%S", tmp, sizeof tmp); - ds_put_strftime(s, tmp, true); + p = fetch_braces(p, "%Y-%m-%d %H:%M:%S.###", tmp, sizeof tmp); + ds_put_strftime_msec(s, tmp, time_wall_msec(), true); break; case 'm': /* Format user-supplied log message and trim trailing new-lines. */ @@ -711,7 +762,7 @@ format_log_message(const struct vlog_module *module, enum vlog_level level, } break; case 'N': - ds_put_format(s, "%u", msg_num); + ds_put_format(s, "%u", *msg_num_get_unsafe()); break; case 'n': ds_put_char(s, '\n'); @@ -726,9 +777,11 @@ format_log_message(const struct vlog_module *module, enum vlog_level level, ds_put_format(s, "%lld", time_msec() - time_boot_msec()); break; case 't': + subprogram_name = get_subprogram_name(); ds_put_cstr(s, subprogram_name[0] ? subprogram_name : "main"); break; case 'T': + subprogram_name = get_subprogram_name(); if (subprogram_name[0]) { ds_put_format(s, "(%s)", subprogram_name); } @@ -761,21 +814,24 @@ vlog_valist(const struct vlog_module *module, enum vlog_level level, { bool log_to_console = module->levels[VLF_CONSOLE] >= level; bool log_to_syslog = module->levels[VLF_SYSLOG] >= level; - bool log_to_file = module->levels[VLF_FILE] >= level && log_fd >= 0; + bool log_to_file; + + ovs_mutex_lock(&log_file_mutex); + log_to_file = module->levels[VLF_FILE] >= level && log_fd >= 0; + ovs_mutex_unlock(&log_file_mutex); if (log_to_console || log_to_syslog || log_to_file) { int save_errno = errno; - static unsigned int msg_num; struct ds s; vlog_init(); ds_init(&s); ds_reserve(&s, 1024); - msg_num++; + ++*msg_num_get(); + ovs_rwlock_rdlock(&pattern_rwlock); if (log_to_console) { - format_log_message(module, level, VLF_CONSOLE, msg_num, - message, args, &s); + format_log_message(module, level, VLF_CONSOLE, message, args, &s); ds_put_char(&s, '\n'); fputs(ds_cstr(&s), stderr); } @@ -785,8 +841,7 @@ vlog_valist(const struct vlog_module *module, enum vlog_level level, char *save_ptr = NULL; char *line; - format_log_message(module, level, VLF_SYSLOG, msg_num, - message, args, &s); + format_log_message(module, level, VLF_SYSLOG, message, args, &s); for (line = strtok_r(s.string, "\n", &save_ptr); line; line = strtok_r(NULL, "\n", &save_ptr)) { syslog(syslog_level, "%s", line); @@ -794,11 +849,23 @@ vlog_valist(const struct vlog_module *module, enum vlog_level level, } if (log_to_file) { - format_log_message(module, level, VLF_FILE, msg_num, - message, args, &s); + format_log_message(module, level, VLF_FILE, message, args, &s); ds_put_char(&s, '\n'); - vlog_write_file(&s); + + ovs_mutex_lock(&log_file_mutex); + if (log_fd >= 0) { + if (log_writer) { + async_append_write(log_writer, s.string, s.length); + if (level == VLL_EMER) { + async_append_flush(log_writer); + } + } else { + ignore(write(log_fd, s.string, s.length)); + } + } + ovs_mutex_unlock(&log_file_mutex); } + ovs_rwlock_unlock(&pattern_rwlock); ds_destroy(&s); errno = save_errno; @@ -898,6 +965,7 @@ vlog_should_drop(const struct vlog_module *module, enum vlog_level level, return true; } + ovs_mutex_lock(&rl->mutex); if (!token_bucket_withdraw(&rl->token_bucket, VLOG_MSG_TOKENS)) { time_t now = time_now(); if (!rl->n_dropped) { @@ -905,21 +973,26 @@ vlog_should_drop(const struct vlog_module *module, enum vlog_level level, } rl->last_dropped = now; rl->n_dropped++; + ovs_mutex_unlock(&rl->mutex); return true; } - if (rl->n_dropped) { + if (!rl->n_dropped) { + ovs_mutex_unlock(&rl->mutex); + } else { time_t now = time_now(); + unsigned int n_dropped = rl->n_dropped; unsigned int first_dropped_elapsed = now - rl->first_dropped; unsigned int last_dropped_elapsed = now - rl->last_dropped; + rl->n_dropped = 0; + ovs_mutex_unlock(&rl->mutex); vlog(module, level, "Dropped %u log messages in last %u seconds (most recently, " "%u seconds ago) due to excessive rate", - rl->n_dropped, first_dropped_elapsed, last_dropped_elapsed); - - rl->n_dropped = 0; + n_dropped, first_dropped_elapsed, last_dropped_elapsed); } + return false; } @@ -946,59 +1019,3 @@ vlog_usage(void) " (default: %s/%s.log)\n", ovs_logdir(), program_name); } - -static bool vlog_async_inited = false; - -static worker_request_func vlog_async_write_request_cb; - -static void -vlog_write_file(struct ds *s) -{ - if (worker_is_running()) { - static bool in_worker_request = false; - if (!in_worker_request) { - in_worker_request = true; - - worker_request(s->string, s->length, - &log_fd, vlog_async_inited ? 0 : 1, - vlog_async_write_request_cb, NULL, NULL); - vlog_async_inited = true; - - in_worker_request = false; - return; - } else { - /* We've been entered recursively. This can happen if - * worker_request(), or a function that it calls, tries to log - * something. We can't call worker_request() recursively, so fall - * back to writing the log file directly. */ - COVERAGE_INC(vlog_recursive); - } - } - ignore(write(log_fd, s->string, s->length)); -} - -static void -vlog_update_async_log_fd(void) -{ - if (worker_is_running()) { - worker_request(NULL, 0, &log_fd, 1, vlog_async_write_request_cb, - NULL, NULL); - vlog_async_inited = true; - } -} - -static void -vlog_async_write_request_cb(struct ofpbuf *request, - const int *fd, size_t n_fds) -{ - if (n_fds > 0) { - if (log_fd >= 0) { - close(log_fd); - } - log_fd = *fd; - } - - if (request->size > 0) { - ignore(write(log_fd, request->data, request->size)); - } -}