On Tue, 20 May 2014 10:44:49 +1000 Dave Chinner <da...@fromorbit.com> wrote:
> @@ -258,14 +258,23 @@ xfs_bmapi_allocate_worker( > struct xfs_bmalloca *args = container_of(work, > struct xfs_bmalloca, work); > unsigned long pflags; > + unsigned long new_pflags = PF_FSTRANS; > > - /* we are in a transaction context here */ > - current_set_flags_nested(&pflags, PF_FSTRANS); > + /* > + * we are in a transaction context here, but may also be doing work > + * in kswapd context, and hence we may need to inherit that state > + * temporarily to ensure that we don't block waiting for memory reclaim > + * in any way. > + */ > + if (args->kswapd) > + new_pflags |= PF_MEMALLOC | PF_SWAPWRITE | PF_KSWAPD; So current_is_kswapd() returns true for a thread which is not kswapd. That's a bit smelly. Should this thread really be incrementing KSWAPD_INODESTEAL instead of PGINODESTEAL, for example? current_is_kswapd() does a range of things, only one(?) of which you actually want. It would be cleaner to create a new PF_ flag to select just that behavior. That's a better model than telling the world "I am magic and special". But we're awfully close to running out of PF_ space and I don't know if this ugly justifies consuming a flag. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
