On Wed, 08 Jun 2011 05:32:37 +0800 Wu Fengguang <fengguang.wu@xxxxxxxxx> wrote: > sync(2) is performed in two stages: the WB_SYNC_NONE sync and the > WB_SYNC_ALL sync. Identify the first stage with .tagged_writepages and > do livelock prevention for it, too. > > Note that writeback_inodes_sb() is called by not only sync(), they are > treated the same because the other callers also need livelock prevention. > > Impact: It changes the order in which pages/inodes are synced to disk. > Now in the WB_SYNC_NONE stage, it won't proceed to write the next inode > until finished with the current inode. What problem is this patch actually fixing? It sounds like there's some livelock scenario in the WB_SYNC_NONE phase. otoh the final paragraph implies that the WB_SYNC_NONE phase is failing to write some pages under some situations. Suggest that the changelog be fleshed out to cover all of this. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
