3.0 patches

diff --git a/queue-3.0/memcg-fix-vmscan-count-in-small-memcgs.patch b/queue-3.0/memcg-fix-vmscan-count-in-small-memcgs.patch
new file mode 100644 (file)
index 0000000..e4a8fed
--- /dev/null
+++ b/queue-3.0/memcg-fix-vmscan-count-in-small-memcgs.patch
@@ -0,0 +1,116 @@
+From 4508378b9523e22a2a0175d8bf64d932fb10a67d Mon Sep 17 00:00:00 2001
+From: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
+Date: Tue, 26 Jul 2011 16:08:24 -0700
+Subject: memcg: fix vmscan count in small memcgs
+
+From: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
+
+commit 4508378b9523e22a2a0175d8bf64d932fb10a67d upstream.
+
+Commit 246e87a93934 ("memcg: fix get_scan_count() for small targets")
+fixes the memcg/kswapd behavior against small targets and prevent vmscan
+priority too high.
+
+But the implementation is too naive and adds another problem to small
+memcg.  It always force scan to 32 pages of file/anon and doesn't handle
+swappiness and other rotate_info.  It makes vmscan to scan anon LRU
+regardless of swappiness and make reclaim bad.  This patch fixes it by
+adjusting scanning count with regard to swappiness at el.
+
+At a test "cat 1G file under 300M limit." (swappiness=20)
+ before patch
+        scanned_pages_by_limit 360919
+        scanned_anon_pages_by_limit 180469
+        scanned_file_pages_by_limit 180450
+        rotated_pages_by_limit 31
+        rotated_anon_pages_by_limit 25
+        rotated_file_pages_by_limit 6
+        freed_pages_by_limit 180458
+        freed_anon_pages_by_limit 19
+        freed_file_pages_by_limit 180439
+        elapsed_ns_by_limit 429758872
+ after patch
+        scanned_pages_by_limit 180674
+        scanned_anon_pages_by_limit 24
+        scanned_file_pages_by_limit 180650
+        rotated_pages_by_limit 35
+        rotated_anon_pages_by_limit 24
+        rotated_file_pages_by_limit 11
+        freed_pages_by_limit 180634
+        freed_anon_pages_by_limit 0
+        freed_file_pages_by_limit 180634
+        elapsed_ns_by_limit 367119089
+        scanned_pages_by_system 0
+
+the numbers of scanning anon are decreased(as expected), and elapsed time
+reduced. By this patch, small memcgs will work better.
+(*) Because the amount of file-cache is much bigger than anon,
+    recalaim_stat's rotate-scan counter make scanning files more.
+
+Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
+Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
+Cc: Michal Hocko <mhocko@suse.cz>
+Cc: Ying Han <yinghan@google.com>
+Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
+
+---
+ mm/vmscan.c |   18 ++++++++++++------
+ 1 file changed, 12 insertions(+), 6 deletions(-)
+
+--- a/mm/vmscan.c
++++ b/mm/vmscan.c
+@@ -1748,6 +1748,7 @@ static void get_scan_count(struct zone *
+       enum lru_list l;
+       int noswap = 0;
+       int force_scan = 0;
++      unsigned long nr_force_scan[2];
+ 
+ 
+       anon  = zone_nr_lru_pages(zone, sc, LRU_ACTIVE_ANON) +
+@@ -1770,6 +1771,8 @@ static void get_scan_count(struct zone *
+               fraction[0] = 0;
+               fraction[1] = 1;
+               denominator = 1;
++              nr_force_scan[0] = 0;
++              nr_force_scan[1] = SWAP_CLUSTER_MAX;
+               goto out;
+       }
+ 
+@@ -1781,6 +1784,8 @@ static void get_scan_count(struct zone *
+                       fraction[0] = 1;
+                       fraction[1] = 0;
+                       denominator = 1;
++                      nr_force_scan[0] = SWAP_CLUSTER_MAX;
++                      nr_force_scan[1] = 0;
+                       goto out;
+               }
+       }
+@@ -1829,6 +1834,11 @@ static void get_scan_count(struct zone *
+       fraction[0] = ap;
+       fraction[1] = fp;
+       denominator = ap + fp + 1;
++      if (force_scan) {
++              unsigned long scan = SWAP_CLUSTER_MAX;
++              nr_force_scan[0] = div64_u64(scan * ap, denominator);
++              nr_force_scan[1] = div64_u64(scan * fp, denominator);
++      }
+ out:
+       for_each_evictable_lru(l) {
+               int file = is_file_lru(l);
+@@ -1849,12 +1859,8 @@ out:
+                * memcg, priority drop can cause big latency. So, it's better
+                * to scan small amount. See may_noscan above.
+                */
+-              if (!scan && force_scan) {
+-                      if (file)
+-                              scan = SWAP_CLUSTER_MAX;
+-                      else if (!noswap)
+-                              scan = SWAP_CLUSTER_MAX;
+-              }
++              if (!scan && force_scan)
++                      scan = nr_force_scan[file];
+               nr[l] = scan;
+       }
+ }

diff --git a/queue-3.0/series b/queue-3.0/series
index 21713ef525bca580d501b9dc9659f61fcd53d05b..d7e3cde1d42971cf9a7e0bf27a713fa3cc828440 100644 (file)
--- a/queue-3.0/series
+++ b/queue-3.0/series
@@ -227,3 +227,4 @@ asoc-ssm2602-re-enable-oscillator-after-suspend.patch
 alsa-hda-realtek-avoid-bogus-hp-pin-assignment.patch
 alsa-hda-no-power-nids-on-92hd93.patch
 alsa-usb-audio-check-for-possible-chip-null-pointer-before-clearing-probing-flag.patch
+memcg-fix-vmscan-count-in-small-memcgs.patch