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

[Eric Dumazet <eric.dumazet@gmail.com>]

From: Eric Dumazet <edumazet@google.com>

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.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: David Rientjes <rientjes@google.com>
---
 mm/vmalloc.c |    1 +
 1 file changed, 1 insertion(+)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index f64632b67196..05a145ed1332 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -1602,6 +1602,7 @@ static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
 			goto fail;
 		}
 		area->pages[i] = page;
+		cond_resched();
 	}
 
 	if (map_vm_area(area, prot, &pages))