X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Freadahead-collect.c;h=3c48a02fc9e49dc9a92c3e43d4715a0dbcbfbbe9;hp=0637c91de30dacd2178524a6d3fc4435550d60d9;hb=7640a5de1b3ffe6547200ad204d14e4f067caf4f;hpb=8260358d5a04912223e8a0062b70a621e2241e96 diff --git a/src/readahead-collect.c b/src/readahead-collect.c index 0637c91de..3c48a02fc 100644 --- a/src/readahead-collect.c +++ b/src/readahead-collect.c @@ -41,6 +41,7 @@ #include #include #include +#include #include "missing.h" #include "util.h" @@ -53,9 +54,9 @@ * * - detect ssd on btrfs/lvm... * - read ahead directories - * - sd_readahead_cancel * - gzip? * - remount rw? + * - handle files where nothing is in mincore * - does ioprio_set work with fadvise()? */ @@ -63,6 +64,12 @@ static unsigned arg_files_max = 16*1024; static off_t arg_file_size_max = READAHEAD_FILE_SIZE_MAX; static usec_t arg_timeout = 2*USEC_PER_MINUTE; +static ReadaheadShared *shared = NULL; + +/* Avoid collisions with the NULL pointer */ +#define SECTOR_TO_PTR(s) ULONG_TO_PTR((s)+1) +#define PTR_TO_SECTOR(p) (PTR_TO_ULONG(p)-1) + static int btrfs_defrag(int fd) { struct btrfs_ioctl_vol_args data; @@ -85,6 +92,13 @@ static int pack_file(FILE *pack, const char *fn, bool on_btrfs) { assert(fn); if ((fd = open(fn, O_RDONLY|O_CLOEXEC|O_NOATIME|O_NOCTTY|O_NOFOLLOW)) < 0) { + + if (errno == ENOENT) + return 0; + + if (errno == EPERM || errno == EACCES) + return 0; + log_warning("open(%s) failed: %m", fn); r = -errno; goto finish; @@ -105,9 +119,10 @@ static int pack_file(FILE *pack, const char *fn, bool on_btrfs) { goto finish; } - pages = l / PAGE_SIZE; + pages = l / page_size(); vec = alloca(pages); + memset(vec, 0, pages); if (mincore(start, l, vec) < 0) { log_warning("mincore(%s) failed: %m", fn); r = -errno; @@ -199,12 +214,13 @@ static int qsort_compare(const void *a, const void *b) { static int collect(const char *root) { enum { - FD_FANOTIFY, + FD_FANOTIFY, /* Get the actual fs events */ FD_SIGNAL, + FD_INOTIFY, /* We get notifications to quit early via this fd */ _FD_MAX }; struct pollfd pollfd[_FD_MAX]; - int fanotify_fd = -1, signal_fd = -1, r = 0; + int fanotify_fd = -1, signal_fd = -1, inotify_fd = -1, r = 0; pid_t my_pid; Hashmap *files = NULL; Iterator i; @@ -251,6 +267,11 @@ static int collect(const char *root) { goto finish; } + if ((inotify_fd = open_inotify()) < 0) { + r = inotify_fd; + goto finish; + } + not_after = now(CLOCK_MONOTONIC) + arg_timeout; my_pid = getpid(); @@ -260,6 +281,8 @@ static int collect(const char *root) { pollfd[FD_FANOTIFY].events = POLLIN; pollfd[FD_SIGNAL].fd = signal_fd; pollfd[FD_SIGNAL].events = POLLIN; + pollfd[FD_INOTIFY].fd = inotify_fd; + pollfd[FD_INOTIFY].events = POLLIN; sd_notify(0, "READY=1\n" @@ -267,6 +290,17 @@ static int collect(const char *root) { log_debug("Collecting..."); + if (access("/run/systemd/readahead/cancel", F_OK) >= 0) { + log_debug("Collection canceled"); + r = -ECANCELED; + goto finish; + } + + if (access("/run/systemd/readahead/done", F_OK) >= 0) { + log_debug("Got termination request"); + goto done; + } + for (;;) { union { struct fanotify_event_metadata metadata; @@ -298,14 +332,52 @@ static int collect(const char *root) { goto finish; } - if (pollfd[FD_SIGNAL].revents != 0) - break; - if (h == 0) { log_debug("Reached maximum collection time, ending collection."); break; } + if (pollfd[FD_SIGNAL].revents) { + log_debug("Got signal."); + break; + } + + if (pollfd[FD_INOTIFY].revents) { + uint8_t inotify_buffer[sizeof(struct inotify_event) + FILENAME_MAX]; + struct inotify_event *e; + + if ((n = read(inotify_fd, &inotify_buffer, sizeof(inotify_buffer))) < 0) { + if (errno == EINTR || errno == EAGAIN) + continue; + + log_error("Failed to read inotify event: %m"); + r = -errno; + goto finish; + } + + e = (struct inotify_event*) inotify_buffer; + while (n > 0) { + size_t step; + + if ((e->mask & IN_CREATE) && streq(e->name, "cancel")) { + log_debug("Collection canceled"); + r = -ECANCELED; + goto finish; + } + + if ((e->mask & IN_CREATE) && streq(e->name, "done")) { + log_debug("Got termination request"); + goto done; + } + + step = sizeof(struct inotify_event) + e->len; + assert(step <= (size_t) n); + + e = (struct inotify_event*) ((uint8_t*) e + step); + n -= step; + } + } + if ((n = read(fanotify_fd, &data, sizeof(data))) < 0) { if (errno == EINTR || errno == EAGAIN) @@ -317,41 +389,50 @@ static int collect(const char *root) { } for (m = &data.metadata; FAN_EVENT_OK(m, n); m = FAN_EVENT_NEXT(m, n)) { + char fn[PATH_MAX]; + int k; - if (m->pid != my_pid && m->fd >= 0) { - char fn[PATH_MAX]; - int k; + if (m->fd < 0) + goto next_iteration; - snprintf(fn, sizeof(fn), "/proc/self/fd/%i", m->fd); - char_array_0(fn); + if (m->pid == my_pid) + goto next_iteration; - if ((k = readlink_malloc(fn, &p)) >= 0) { + __sync_synchronize(); + if (m->pid == shared->replay) + goto next_iteration; - if (startswith(p, "/tmp") || - hashmap_get(files, p)) - /* Not interesting, or - * already read */ - free(p); - else { - unsigned long ul; + snprintf(fn, sizeof(fn), "/proc/self/fd/%i", m->fd); + char_array_0(fn); - ul = fd_first_block(m->fd); + if ((k = readlink_malloc(fn, &p)) >= 0) { + if (startswith(p, "/tmp") || + endswith(p, " (deleted)") || + hashmap_get(files, p)) + /* Not interesting, or + * already read */ + free(p); + else { + unsigned long ul; - if ((k = hashmap_put(files, p, ULONG_TO_PTR(ul))) < 0) { - log_warning("set_put() failed: %s", strerror(-k)); - free(p); - } + ul = fd_first_block(m->fd); + + if ((k = hashmap_put(files, p, SECTOR_TO_PTR(ul))) < 0) { + log_warning("set_put() failed: %s", strerror(-k)); + free(p); } + } - } else - log_warning("readlink(%s) failed: %s", fn, strerror(-k)); - } + } else + log_warning("readlink(%s) failed: %s", fn, strerror(-k)); + next_iteration: if (m->fd) close_nointr_nofail(m->fd); } } +done: if (fanotify_fd >= 0) { close_nointr_nofail(fanotify_fd); fanotify_fd = -1; @@ -359,10 +440,10 @@ static int collect(const char *root) { log_debug("Writing Pack File..."); - on_ssd = fs_on_ssd(root); + on_ssd = fs_on_ssd(root) > 0; log_debug("On SSD: %s", yes_no(on_ssd)); - on_btrfs = statfs(root, &sfs) >= 0 && sfs.f_type == BTRFS_SUPER_MAGIC; + on_btrfs = statfs(root, &sfs) >= 0 && (long) sfs.f_type == (long) BTRFS_SUPER_MAGIC; log_debug("On btrfs: %s", yes_no(on_btrfs)); asprintf(&pack_fn, "%s/.readahead", root); @@ -409,7 +490,7 @@ static int collect(const char *root) { j = ordered; HASHMAP_FOREACH_KEY(q, p, files, i) { j->path = p; - j->block = PTR_TO_ULONG(q); + j->block = PTR_TO_SECTOR(q); j++; } @@ -451,6 +532,9 @@ finish: if (signal_fd >= 0) close_nointr_nofail(signal_fd); + if (inotify_fd >= 0) + close_nointr_nofail(inotify_fd); + if (pack) { fclose(pack); unlink(pack_fn_new); @@ -460,7 +544,7 @@ finish: free(pack_fn); while ((p = hashmap_steal_first_key(files))) - free(q); + free(p); hashmap_free(files); @@ -556,6 +640,7 @@ static int parse_argv(int argc, char *argv[]) { int main(int argc, char *argv[]) { int r; + const char *root; log_set_target(LOG_TARGET_SYSLOG_OR_KMSG); log_parse_environment(); @@ -564,12 +649,30 @@ int main(int argc, char *argv[]) { if ((r = parse_argv(argc, argv)) <= 0) return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS; + root = optind < argc ? argv[optind] : "/"; + + if (fs_on_read_only(root) > 0) { + log_info("Disabling readahead collector due to read-only media."); + return 0; + } + if (!enough_ram()) { log_info("Disabling readahead collector due to low memory."); return 0; } - if (collect(optind < argc ? argv[optind] : "/") < 0) + if (detect_virtualization(NULL) > 0) { + log_info("Disabling readahead collector due to execution in virtualized environment."); + return 0; + } + + if (!(shared = shared_get())) + return 1; + + shared->collect = getpid(); + __sync_synchronize(); + + if (collect(root) < 0) return 1; return 0;