> > > > > In general, writepage is supposed to do work without blocking on > > > > > expensive locks that will get pdflush and dirty reclaim stuck in this > > > > > fashion. You'll probably have to take the same approach reiserfs does > > > > > in data=journal mode, which is leaving the page dirty if > > > > > fuse_get_req_wp > > > > > is going to block without making progress. > > > > > > > > Pdflush, and dirty reclaim set wbc->nonblocking to true. > > > > balance_dirty_pages and fsync don't. The problem here is that > > > > Andrew's patch is wrong to let balance_dirty_pages() try to write back > > > > pages from a different queue. > > > > > > async or sync, writepage is supposed to either make progress or bail. > > > loopback aside, if the fuse call is blocking long term, you're going to > > > run into problems. > > > > Hmm, like what? > > Something a little different from what you're seeing. Basically if the > PF_MEMALLOC paths end up waiting on a filesystem transaction, and that > transaction is waiting for more ram, the system will eventually grind to > a halt. data=journal is the easiest way to hit it, since writepage > always logs at least 4k. > > WB_SYNC_NONE and wbc->nonblocking aren't a great test, in reiser I > resorted to testing PF_MEMALLOC.
I'm not pretending to understand how journaling filesystems work, but this shouldn't be an issue with fuse. Can you show me a call path, where PF_MEMALLOC is set and .nonblocking is not? Thanks, Miklos - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/