[PATCH mmotm] mm, sl[au]b: print gfp_flags as strings in slab_out_of_memory()

From: Vlastimil Babka
Date: Tue Mar 01 2016 - 14:09:34 EST


We can now print gfp_flags more human-readable. Make use of this in
slab_out_of_memory() for SLUB and SLAB. Also convert the SLAB variant it to
pr_warn() along the way.

Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: Pekka Enberg <penberg@xxxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
---
This could go after e.g. mm-oom-print-symbolic-gfp_flags-in-oom-warning.patch
Quick grep suggests there are no other places to convert.

mm/slab.c | 10 ++++------
mm/slub.c | 4 ++--
2 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/mm/slab.c b/mm/slab.c
index b9ee77554008..c87088ae2351 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -1347,10 +1347,9 @@ slab_out_of_memory(struct kmem_cache *cachep, gfp_t gfpflags, int nodeid)
if ((gfpflags & __GFP_NOWARN) || !__ratelimit(&slab_oom_rs))
return;

- printk(KERN_WARNING
- "SLAB: Unable to allocate memory on node %d (gfp=0x%x)\n",
- nodeid, gfpflags);
- printk(KERN_WARNING " cache: %s, object size: %d, order: %d\n",
+ pr_warn("SLAB: Unable to allocate memory on node %d, gfp=%#x(%pGg)\n",
+ nodeid, gfpflags, &gfpflags);
+ pr_warn(" cache: %s, object size: %d, order: %d\n",
cachep->name, cachep->size, cachep->gfporder);

for_each_kmem_cache_node(cachep, node, n) {
@@ -1374,8 +1373,7 @@ slab_out_of_memory(struct kmem_cache *cachep, gfp_t gfpflags, int nodeid)

num_slabs += active_slabs;
num_objs = num_slabs * cachep->num;
- printk(KERN_WARNING
- " node %d: slabs: %ld/%ld, objs: %ld/%ld, free: %ld\n",
+ pr_warn(" node %d: slabs: %ld/%ld, objs: %ld/%ld, free: %ld\n",
node, active_slabs, num_slabs, active_objs, num_objs,
free_objects);
}
diff --git a/mm/slub.c b/mm/slub.c
index d86720d93cda..8caaf2903241 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2248,8 +2248,8 @@ slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid)
if ((gfpflags & __GFP_NOWARN) || !__ratelimit(&slub_oom_rs))
return;

- pr_warn("SLUB: Unable to allocate memory on node %d (gfp=0x%x)\n",
- nid, gfpflags);
+ pr_warn("SLUB: Unable to allocate memory on node %d, gfp=%#x(%pGg)\n",
+ nid, gfpflags, &gfpflags);
pr_warn(" cache: %s, object size: %d, buffer size: %d, default order: %d, min order: %d\n",
s->name, s->object_size, s->size, oo_order(s->oo),
oo_order(s->min));
--
2.7.2