On 03/02/2016 03:22 PM, Joonsoo Kim wrote: > 2016-03-02 23:09 GMT+09:00 Vlastimil Babka <vbabka@xxxxxxx>: >> 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); I'm more inclined to fold it in that case. > Thanks. > >>> Result of patch 4 >>> and patch 5 would be same. >> >> >> It's certainly possible to fold patch 5 into 4. I posted them separately >> mainly to make review more feasible. But the differences in results are >> already quite small. >> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>