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  1. 15 6月, 2014 1 次提交
    • A
      fix __swap_writepage() compile failure on old gcc versions · 05064084
      由 Al Viro 提交于 
      Tetsuo Handa wrote:
 "Commit 62a8067a ("bio_vec-backed iov_iter") introduced an unnamed
  union inside a struct which gcc-4.4.7 cannot handle.  Name the unnamed
   union as u in order to fix build failure"

Let's do this instead: there is only one place in the entire tree that
steps into this breakage.  Anon structs and unions work in older gcc
versions; as the matter of fact, we have those in the tree - see e.g.
struct ieee80211_tx_info in include/net/mac80211.h

What doesn't work is handling their initializers:

struct {
	int a;
	union {
		int b;
		char c;
	};
} x[2] = {{.a = 1, .c = 'a'}, {.a = 0, .b = 1}};

is the obvious syntax for initializer, perfectly fine for C11 and
handled correctly by gcc-4.7 or later.

Earlier versions, though, break on it - declaration is fine and so's
access to fields (i.e.  x[0].c = 'a'; would produce the right code), but
members of the anon structs and unions are not inserted into the right
namespace.  Tellingly, those older versions will not barf on struct {int
a; struct {int a;};}; - looks like they just have it hacked up somewhere
around the handling of .  and -> instead of doing the right thing.

The easiest way to deal with that crap is to turn initialization of
those fields (in the only place where we have such initializer of
iov_iter) into plain assignment.
Reported-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      05064084
  3. 12 6月, 2014 1 次提交
  5. 09 6月, 2014 1 次提交
    • L
      Don't trigger congestion wait on dirty-but-not-writeout pages · b738d764
      由 Linus Torvalds 提交于 
      shrink_inactive_list() used to wait 0.1s to avoid congestion when all
the pages that were isolated from the inactive list were dirty but not
under active writeback.  That makes no real sense, and apparently causes
major interactivity issues under some loads since 3.11.

The ostensible reason for it was to wait for kswapd to start writing
pages, but that seems questionable as well, since the congestion wait
code seems to trigger for kswapd itself as well.  Also, the logic behind
delaying anything when we haven't actually started writeback is not
clear - it only delays actually starting that writeback.

We'll still trigger the congestion waiting if

 (a) the process is kswapd, and we hit pages flagged for immediate
     reclaim

 (b) the process is not kswapd, and the zone backing dev writeback is
     actually congested.

This probably needs to be revisited, but as it is this fixes a reported
regression.
Reported-by: NFelipe Contreras <felipe.contreras@gmail.com>
Pinpointed-by: NHillf Danton <dhillf@gmail.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      b738d764
  7. 07 6月, 2014 14 次提交
  9. 06 6月, 2014 1 次提交
  11. 05 6月, 2014 22 次提交