On Mon, Mar 01, 2010 at 05:02:08PM -0500, Vivek Goyal wrote: > > @@ -686,10 +699,14 @@ void throttle_vm_writeout(gfp_t gfp_mask) > > */ > > dirty_thresh += dirty_thresh / 10; /* wheeee... */ > > > > - if (global_page_state(NR_UNSTABLE_NFS) + > > - global_page_state(NR_WRITEBACK) <= dirty_thresh) > > - break; > > - congestion_wait(BLK_RW_ASYNC, HZ/10); > > + > > + dirty = mem_cgroup_page_stat(MEMCG_NR_DIRTY_WRITEBACK_PAGES); > > + if (dirty < 0) > > + dirty = global_page_state(NR_UNSTABLE_NFS) + > > + global_page_state(NR_WRITEBACK); > > dirty is unsigned long. As mentioned last time, above will never be true? > In general these patches look ok to me. I will do some testing with these. Re-introduced the same bug. My bad. :( The value returned from mem_cgroup_page_stat() can be negative, i.e. when memory cgroup is disabled. We could simply use a long for dirty, the unit is in # of pages so s64 should be enough. Or cast dirty to long only for the check (see below). Thanks! -Andrea Signed-off-by: Andrea Righi <arighi@xxxxxxxxxxx> --- mm/page-writeback.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/mm/page-writeback.c b/mm/page-writeback.c index d83f41c..dbee976 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -701,7 +701,7 @@ void throttle_vm_writeout(gfp_t gfp_mask) dirty = mem_cgroup_page_stat(MEMCG_NR_DIRTY_WRITEBACK_PAGES); - if (dirty < 0) + if ((long)dirty < 0) dirty = global_page_state(NR_UNSTABLE_NFS) + global_page_state(NR_WRITEBACK); if (dirty <= dirty_thresh) -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>