From: Eric Dumazet <edumazet@google.com>
Date: Wed, 6 Aug 2014 23:06:25 +0000 (-0700)
Subject: mm/vmalloc.c: add a schedule point to vmalloc()
X-Git-Tag: firefly_0821_release~176^2~3462^2~140
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=660654f90e7f8f6d8163276d47fc1573a39c7007;p=firefly-linux-kernel-4.4.55.git

mm/vmalloc.c: add a schedule point to vmalloc()

It is not uncommon on busy servers to get stuck hundred of ms in
vmalloc() calls (like file descriptor expansions).

Add a cond_resched() to __vmalloc_area_node() to be gentle to
other tasks.

[akpm@linux-foundation.org: only do it for __GFP_WAIT, per David]
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Hugh Dickins <hughd@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index fdbb116ee669..a3cad905f560 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -1602,6 +1602,8 @@ static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
 			goto fail;
 		}
 		area->pages[i] = page;
+		if (gfp_mask & __GFP_WAIT)
+			cond_resched();
 	}
 
 	if (map_vm_area(area, prot, &pages))