X-Git-Url: http://git.vrable.net/?a=blobdiff_plain;f=bluesky%2Flog.c;h=97b4f304aea1552aa103cd3404c85fde3cb92dae;hb=2f883084c4393dc7b730df2e778b9f2fc14f70e0;hp=c879ccd292df922f7cce7247e1bf5f69b6ade56f;hpb=831077a3e64381afd0297d8ae5c21d5cdede5f4a;p=bluesky.git diff --git a/bluesky/log.c b/bluesky/log.c index c879ccd..97b4f30 100644 --- a/bluesky/log.c +++ b/bluesky/log.c @@ -41,22 +41,6 @@ #define HEADER_MAGIC 0x676f4c0a #define FOOTER_MAGIC 0x2e435243 -struct log_header { - uint32_t magic; // HEADER_MAGIC - uint8_t type; // Object type + '0' - uint32_t offset; // Starting byte offset of the log header - uint32_t size1; // Size of the data item (bytes) - uint32_t size2; // - uint32_t size3; // - uint64_t inum; // Inode which owns this data, if any - BlueSkyCloudID id; // Object identifier -} __attribute__((packed)); - -struct log_footer { - uint32_t magic; // FOOTER_MAGIC - uint32_t crc; // Computed from log_header to log_footer.magic -} __attribute__((packed)); - static void writebuf(int fd, const char *buf, size_t len) { while (len > 0) { @@ -226,10 +210,11 @@ static gpointer log_thread(gpointer d) writebuf(log->fd, (const char *)&footer, sizeof(footer)); item->log_seq = log->seq_num; - item->log_offset = offset + sizeof(header); - item->log_size = item->data->len; + item->log_offset = offset; + item->log_size = size; + item->data_size = item->data->len; - offset += sizeof(header) + sizeof(footer) + item->data->len; + offset += size; g_string_free(data1, TRUE); g_string_free(data2, TRUE); @@ -243,7 +228,7 @@ static gpointer log_thread(gpointer d) item->data = NULL; bluesky_cloudlog_fetch(item); - log->committed = g_slist_prepend(log->committed, item); + log->committed = g_slist_prepend(log->committed, item); g_atomic_int_add(&item->data_lock_count, -1); g_mutex_unlock(item->lock); @@ -300,6 +285,46 @@ void bluesky_log_finish_all(GList *log_items) } } +/* Return a committed cloud log record that can be used as a watermark for how + * much of the journal has been written. */ +BlueSkyCloudLog *bluesky_log_get_commit_point(BlueSkyFS *fs) +{ + BlueSkyCloudLog *marker = bluesky_cloudlog_new(fs, NULL); + marker->type = LOGTYPE_JOURNAL_MARKER; + marker->data = bluesky_string_new(g_strdup(""), 0); + bluesky_cloudlog_sync(marker); + + g_mutex_lock(marker->lock); + while ((marker->pending_write & CLOUDLOG_JOURNAL)) + g_cond_wait(marker->cond, marker->lock); + g_mutex_unlock(marker->lock); + + return marker; +} + +void bluesky_log_write_commit_point(BlueSkyFS *fs, BlueSkyCloudLog *marker) +{ + BlueSkyCloudLog *commit = bluesky_cloudlog_new(fs, NULL); + commit->type = LOGTYPE_JOURNAL_CHECKPOINT; + + uint32_t seq, offset; + seq = GUINT32_TO_LE(marker->log_seq); + offset = GUINT32_TO_LE(marker->log_offset); + GString *loc = g_string_new(""); + g_string_append_len(loc, (const gchar *)&seq, sizeof(seq)); + g_string_append_len(loc, (const gchar *)&offset, sizeof(offset)); + commit->data = bluesky_string_new_from_gstring(loc); + bluesky_cloudlog_sync(commit); + + g_mutex_lock(commit->lock); + while ((commit->pending_write & CLOUDLOG_JOURNAL)) + g_cond_wait(commit->cond, commit->lock); + g_mutex_unlock(commit->lock); + + bluesky_cloudlog_unref(marker); + bluesky_cloudlog_unref(commit); +} + /* Memory-map the given log object into memory (read-only) and return a pointer * to it. */ static int page_size = 0; @@ -647,7 +672,8 @@ static gboolean validate_journal_item(const char *buf, size_t len, off_t offset) /* Scan through a journal segment to extract correctly-written items (those * that pass sanity checks and have a valid checksum). */ -static void bluesky_replay_scan_journal(const char *buf, size_t len) +static void bluesky_replay_scan_journal(const char *buf, size_t len, + uint32_t *seq, uint32_t *start_offset) { const struct log_header *header; off_t offset = 0; @@ -657,6 +683,13 @@ static void bluesky_replay_scan_journal(const char *buf, size_t len) size_t size = GUINT32_FROM_LE(header->size1) + GUINT32_FROM_LE(header->size2) + GUINT32_FROM_LE(header->size3); + + if (header->type - '0' == LOGTYPE_JOURNAL_CHECKPOINT) { + const uint32_t *data = (const uint32_t *)((const char *)header + sizeof(struct log_header)); + *seq = GUINT32_FROM_LE(data[0]); + *start_offset = GUINT32_FROM_LE(data[1]); + } + offset += sizeof(struct log_header) + size + sizeof(struct log_footer); } } @@ -705,11 +738,11 @@ static void reload_item(BlueSkyCloudLog *log_item, } static void bluesky_replay_scan_journal2(BlueSkyFS *fs, GList **objects, - int log_seq, + int log_seq, int start_offset, const char *buf, size_t len) { const struct log_header *header; - off_t offset = 0; + off_t offset = start_offset; while (validate_journal_item(buf, len, offset)) { header = (const struct log_header *)(buf + offset); @@ -718,18 +751,8 @@ static void bluesky_replay_scan_journal2(BlueSkyFS *fs, GList **objects, + GUINT32_FROM_LE(header->size2) + GUINT32_FROM_LE(header->size3); - g_mutex_lock(fs->lock); - BlueSkyCloudLog *log_item; - log_item = g_hash_table_lookup(fs->locations, &header->id); - if (log_item == NULL) { - log_item = bluesky_cloudlog_new(fs, &header->id); - g_hash_table_insert(fs->locations, &log_item->id, log_item); - g_mutex_lock(log_item->lock); - } else { - bluesky_cloudlog_ref(log_item); - g_mutex_lock(log_item->lock); - } - g_mutex_unlock(fs->lock); + BlueSkyCloudLog *log_item = bluesky_cloudlog_get(fs, header->id); + g_mutex_lock(log_item->lock); *objects = g_list_prepend(*objects, log_item); log_item->inum = GUINT64_FROM_LE(header->inum); @@ -790,6 +813,7 @@ void bluesky_replay(BlueSkyFS *fs) /* Scan through log files in reverse order to find the most recent commit * record. */ logfiles = g_list_reverse(logfiles); + uint32_t seq_num = 0, start_offset = 0; while (logfiles != NULL) { char *filename = g_strdup_printf("%s/%s", log->log_directory, (char *)logfiles->data); @@ -799,13 +823,16 @@ void bluesky_replay(BlueSkyFS *fs) g_warning("Mapping logfile %s failed!\n", filename); } else { bluesky_replay_scan_journal(g_mapped_file_get_contents(map), - g_mapped_file_get_length(map)); + g_mapped_file_get_length(map), + &seq_num, &start_offset); g_mapped_file_unref(map); } g_free(filename); g_free(logfiles->data); logfiles = g_list_delete_link(logfiles, logfiles); + if (seq_num != 0 || start_offset != 0) + break; } g_list_foreach(logfiles, (GFunc)g_free, NULL); g_list_free(logfiles); @@ -816,11 +843,10 @@ void bluesky_replay(BlueSkyFS *fs) * references, so that any objects which were not linked into persistent * filesystem data structures are freed. */ GList *objects = NULL; - int seq_num = 0; while (TRUE) { char *filename = g_strdup_printf("%s/journal-%08d", log->log_directory, seq_num); - g_print("Replaying file %s\n", filename); + g_print("Replaying file %s from offset %d\n", filename, start_offset); GMappedFile *map = g_mapped_file_new(filename, FALSE, NULL); g_free(filename); if (map == NULL) { @@ -828,11 +854,12 @@ void bluesky_replay(BlueSkyFS *fs) break; } - bluesky_replay_scan_journal2(fs, &objects, seq_num, + bluesky_replay_scan_journal2(fs, &objects, seq_num, start_offset, g_mapped_file_get_contents(map), g_mapped_file_get_length(map)); g_mapped_file_unref(map); seq_num++; + start_offset = 0; } while (objects != NULL) {