X-Git-Url: http://git.vrable.net/?a=blobdiff_plain;f=bluesky%2Fcache.c;h=58b7cd6f1ac79c6b67af07fc4ece5979f872312d;hb=e49fed25d000a51b316b480c1bfb1b00c1f5d345;hp=6a91873c3750002e9956782a802d886ecf7e11f2;hpb=60b4792d65ba4b2a45733894f6a57e6581ddc487;p=bluesky.git diff --git a/bluesky/cache.c b/bluesky/cache.c index 6a91873..58b7cd6 100644 --- a/bluesky/cache.c +++ b/bluesky/cache.c @@ -15,8 +15,14 @@ #define WRITEBACK_DELAY (20 * 1000000) -/* Filesystem caching and cache coherency. */ +/* Filesystem caching and cache coherency. There are actually a couple of + * different tasks that are performed here: + * - Forcing data to the log if needed to reclaim memory or simply if the + * data has been dirty in memory long enough. + * - Writing batches of data to the cloud. + */ +#if 0 static void writeback_complete(gpointer a, gpointer i) { BlueSkyInode *inode = (BlueSkyInode *)i; @@ -41,85 +47,6 @@ static void writeback_complete(gpointer a, gpointer i) g_mutex_unlock(inode->lock); } - -#if 0 -static void flushd_inode(gpointer value, gpointer user_data) -{ - BlueSkyFS *fs = (BlueSkyFS *)user_data; - - BlueSkyInode *inode = (BlueSkyInode *)value; - - g_mutex_lock(inode->lock); - - if (inode->change_count == inode->change_commit) { - uint64_t delay = bluesky_get_current_time() - inode->access_time; - if (delay >= CACHE_CLEAN_DELAY) { - drop_caches(inode); - - /* If the only references are the one we hold and the one in the - * filesystem inum->inode hash table... First check the refcount - * without the lock for speed, but if the check looks good verify - * it after taking the filesystem lock. */ - if (inode->refcount == 2) { - g_mutex_lock(fs->lock); - if (inode->refcount == 2) { - g_log("bluesky/flushd", G_LOG_LEVEL_DEBUG, - "Trying to drop inode %"PRIu64" from cache", - inode->inum); - if (g_hash_table_remove(fs->inodes, &inode->inum)) - bluesky_inode_unref(inode); - } - bluesky_list_unlink(&inode->fs->accessed_list, - inode->accessed_list); - inode->accessed_list = NULL; - bluesky_list_unlink(&inode->fs->dirty_list, - inode->dirty_list); - inode->dirty_list = NULL; - g_mutex_unlock(fs->lock); - } - } - - g_mutex_unlock(inode->lock); - bluesky_inode_unref(inode); - return; - } - - if (inode->change_pending) { - /* Waiting for an earlier writeback to finish, so don't start a new - * writeback yet. */ - g_mutex_unlock(inode->lock); - bluesky_inode_unref(inode); - return; - } - - uint64_t elapsed = bluesky_get_current_time() - inode->change_time; - if (elapsed < WRITEBACK_DELAY) { - /* Give a bit more time before starting writeback. */ - g_mutex_unlock(inode->lock); - bluesky_inode_unref(inode); - return; - } - - inode->change_pending = inode->change_count; - - g_log("bluesky/flushd", G_LOG_LEVEL_DEBUG, - "Starting flush of inode %"PRIu64, inode->inum); - - /* Create a store barrier. All operations part of the writeback will be - * added to this barrier, so when the barrier completes we know that the - * writeback is finished. */ - BlueSkyStoreAsync *barrier = bluesky_store_async_new(fs->store); - barrier->op = STORE_OP_BARRIER; - - bluesky_inode_start_sync(inode, barrier); - - bluesky_store_async_add_notifier(barrier, writeback_complete, inode); - bluesky_store_async_submit(barrier); - bluesky_store_async_unref(barrier); - - g_mutex_unlock(inode->lock); - bluesky_inode_unref(inode); -} #endif static void flushd_dirty_inode(BlueSkyInode *inode) @@ -135,35 +62,12 @@ static void flushd_dirty_inode(BlueSkyInode *inode) if (inode->change_count == inode->change_commit) return; - /* Inode writeback is in progress; put back on the dirty list. */ - if (inode->change_pending) { - /* Waiting for an earlier writeback to finish, so don't start a new - * writeback yet. */ - g_mutex_lock(fs->lock); - inode->change_time = bluesky_get_current_time(); - bluesky_list_unlink(&fs->dirty_list, inode->dirty_list); - inode->dirty_list = bluesky_list_prepend(&fs->dirty_list, inode); - g_mutex_unlock(fs->lock); - return; - } - if (bluesky_verbose) { g_log("bluesky/flushd", G_LOG_LEVEL_DEBUG, "Starting flush of inode %"PRIu64, inode->inum); } - inode->change_pending = inode->change_count; - - /* Create a store barrier. All operations part of the writeback will be - * added to this barrier, so when the barrier completes we know that the - * writeback is finished. */ - BlueSkyStoreAsync *barrier = bluesky_store_async_new(fs->store); - barrier->op = STORE_OP_BARRIER; - bluesky_inode_start_sync(inode, barrier); - - bluesky_store_async_add_notifier(barrier, writeback_complete, inode); - bluesky_store_async_submit(barrier); - bluesky_store_async_unref(barrier); + bluesky_inode_start_sync(inode); } /* Try to flush dirty data to disk, either due to memory pressure or due to @@ -216,7 +120,7 @@ static void drop_caches(BlueSkyInode *inode) bluesky_file_drop_cached(inode); } -/* Drop clean data fromt the cache if needed due to memory pressure. */ +/* Drop clean data from the cache if needed due to memory pressure. */ static void flushd_clean(BlueSkyFS *fs) { g_mutex_lock(fs->lock); @@ -226,8 +130,10 @@ static void flushd_clean(BlueSkyFS *fs) inode_count = 1; while (inode_count-- > 0) { +#if 0 if (g_atomic_int_get(&fs->cache_total) < bluesky_watermark_medium_total) break; +#endif BlueSkyInode *inode; if (fs->accessed_list.prev == NULL) @@ -269,8 +175,8 @@ static gpointer flushd_task(BlueSkyFS *fs) if (!g_mutex_trylock(fs->flushd_lock)) return NULL; flushd_dirty(fs); - flushd_clean(fs); bluesky_cloudlog_write_log(fs); + flushd_clean(fs); g_mutex_unlock(fs->flushd_lock); return NULL;