[patch 05/18] mm/swapfile.c: use kvzalloc for swap_info_struct allocation

[patch 05/18] mm/swapfile.c: use kvzalloc for swap_info_struct allocation

[akpm]

From: Vasily Averin <vvs@virtuozzo.com>
Subject: mm/swapfile.c: use kvzalloc for swap_info_struct allocation

a2468cc9bfdf ("swap: choose swap device according to numa node") changed
'avail_lists' field of 'struct swap_info_struct' to an array.  In popular
linux distros it increased size of swap_info_struct up to 40 Kbytes and
now swap_info_struct allocation requires order-4 page.  Switch to
kvzmalloc allows to avoid unexpected allocation failures.

Link: http://lkml.kernel.org/r/fc23172d-3c75-21e2-d551-8b1808cbe593@virtuozzo.com
Fixes: a2468cc9bfdf ("swap: choose swap device according to numa node")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Acked-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Huang Ying <ying.huang@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---


--- a/mm/swapfile.c~mm-use-kvzalloc-for-swap_info_struct-allocation
+++ a/mm/swapfile.c
@@ -2813,7 +2813,7 @@ static struct swap_info_struct *alloc_sw
 	unsigned int type;
 	int i;
 
-	p = kzalloc(sizeof(*p), GFP_KERNEL);
+	p = kvzalloc(sizeof(*p), GFP_KERNEL);
 	if (!p)
 		return ERR_PTR(-ENOMEM);
 
@@ -2824,7 +2824,7 @@ static struct swap_info_struct *alloc_sw
 	}
 	if (type >= MAX_SWAPFILES) {
 		spin_unlock(&swap_lock);
-		kfree(p);
+		kvfree(p);
 		return ERR_PTR(-EPERM);
 	}
 	if (type >= nr_swapfiles) {
@@ -2838,7 +2838,7 @@ static struct swap_info_struct *alloc_sw
 		smp_wmb();
 		nr_swapfiles++;
 	} else {
-		kfree(p);
+		kvfree(p);
 		p = swap_info[type];
 		/*
 		 * Do not memset this entry: a racing procfs swap_next()
_