2016-03-02 23:40 GMT+09:00 Vlastimil Babka <[email protected]>: > On 03/02/2016 03:22 PM, Joonsoo Kim wrote: >> 2016-03-02 23:09 GMT+09:00 Vlastimil Babka <[email protected]>: >>> On 03/02/2016 02:57 PM, Joonsoo Kim wrote: >>>> >>>> >>>> Yes, I know. >>>> What I'd like to say here is that you need to care current_is_kswapd() in >>>> this patch. This patch unintentionally change the back ground compaction >>>> thread >>>> behaviour to restart compaction by every 64 trials because calling >>>> curret_is_kswapd() >>> >>>> by kcompactd would return false and is treated as direct reclaim. >>> >>> Oh, you mean this path to reset the skip bits. I see. But if skip bits are >>> already reset by kswapd when waking kcompactd, then effect of another (rare) >>> reset in kcompactd itself will be minimal? >> >> If you care current_is_kswapd() in this patch properly (properly means change >> like "current_is_kcompactd()), reset in kswapd would not >> happen because, compact_blockskip_flush would not be set by kcompactd. >> >> In this case, patch 5 would have it's own meaning so cannot be folded. > > So I understand that patch 5 would be just about this? > > - if (compaction_restarting(zone, cc->order) && !current_is_kcompactd()) > + if (compaction_restarting(zone, cc->order)) > __reset_isolation_suitable(zone);
Yeah, you understand correctly. :) > I'm more inclined to fold it in that case. Patch would be just simple, but, I guess it would cause some difference in test result. But, I'm okay for folding. Thanks.
