On Thu 05-11-15 18:50:29, Andrew Morton wrote: > From: Michal Hocko <[email protected]> > Subject: memcg: fix thresholds for 32b architectures. > > 424cdc141380 ("memcg: convert threshold to bytes") has fixed a regression > introduced by 3e32cb2e0a12 ("mm: memcontrol: lockless page counters") > where thresholds were silently converted to use page units rather than > bytes when interpreting the user input. > > The fix is not complete, though, as properly pointed out by Ben Hutchings > during stable backport review. The page count is converted to bytes but > unsigned long is used to hold the value which would be obviously not > sufficient for 32b systems with more than 4G thresholds. The same applies > to usage as taken from mem_cgroup_usage which might overflow. > > Let's remove this bytes vs. pages internal tracking differences and > handle thresholds in page units internally. Chage mem_cgroup_usage() to > return the value in page units and revert 424cdc141380 because this should > be sufficient for the consistent handling. mem_cgroup_read_u64 as the > only users of mem_cgroup_usage outside of the threshold handling code is > converted to give the proper in bytes result. It is doing that already > for page_counter output so this is more consistent as well. > > The value presented to the userspace is still in bytes units. > > Fixes: 424cdc141380 ("memcg: convert threshold to bytes") > Fixes: 3e32cb2e0a12 ("mm: memcontrol: lockless page counters") > Signed-off-by: Michal Hocko <[email protected]> > Reported-by: Ben Hutchings <[email protected]> > Reviewed-by: Vladimir Davydov <[email protected]> > Acked-by: Johannes Weiner <[email protected]> > Cc: <[email protected]>
----- > From: Michal Hocko <[email protected]> > Subject: memcg-fix-thresholds-for-32b-architectures-fix > > Cc: Ben Hutchings <[email protected]> > Cc: Vladimir Davydov <[email protected]> > Cc: Johannes Weiner <[email protected]> > From: Andrew Morton <[email protected]> > Subject: memcg-fix-thresholds-for-32b-architectures-fix-fix > > don't attempt to inline mem_cgroup_usage() > > The compiler ignores the inline anwyay. And __always_inlining it adds 600 > bytes of goop to the .o file. > > Cc: Ben Hutchings <[email protected]> > Cc: Johannes Weiner <[email protected]> > Cc: Michal Hocko <[email protected]> > Cc: Vladimir Davydov <[email protected]> > Signed-off-by: Andrew Morton <[email protected]> This doesn't belong to the changelog. The patch is OK otherwise. -- Michal Hocko SUSE Labs -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
