From: Joonsoo Kim Date: Wed, 16 May 2012 15:13:02 +0000 (+0900) Subject: slub: fix a memory leak in get_partial_node() X-Git-Tag: v3.2.20~50 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=dd881278ba354640bec9f3d6c6dfaef38d2c53b9;p=pandora-kernel.git slub: fix a memory leak in get_partial_node() commit 02d7633fa567be7bf55a993b79d2a31b95ce2227 upstream. In the case which is below, 1. acquire slab for cpu partial list 2. free object to it by remote cpu 3. page->freelist = t then memory leak is occurred. Change acquire_slab() not to zap freelist when it works for cpu partial list. I think it is a sufficient solution for fixing a memory leak. Below is output of 'slabinfo -r kmalloc-256' when './perf stat -r 30 hackbench 50 process 4000 > /dev/null' is done. ***Vanilla*** Sizes (bytes) Slabs Debug Memory ------------------------------------------------------------------------ Object : 256 Total : 468 Sanity Checks : Off Total: 3833856 SlabObj: 256 Full : 111 Redzoning : Off Used : 2004992 SlabSiz: 8192 Partial: 302 Poisoning : Off Loss : 1828864 Loss : 0 CpuSlab: 55 Tracking : Off Lalig: 0 Align : 8 Objects: 32 Tracing : Off Lpadd: 0 ***Patched*** Sizes (bytes) Slabs Debug Memory ------------------------------------------------------------------------ Object : 256 Total : 300 Sanity Checks : Off Total: 2457600 SlabObj: 256 Full : 204 Redzoning : Off Used : 2348800 SlabSiz: 8192 Partial: 33 Poisoning : Off Loss : 108800 Loss : 0 CpuSlab: 63 Tracking : Off Lalig: 0 Align : 8 Objects: 32 Tracing : Off Lpadd: 0 Total and loss number is the impact of this patch. Acked-by: Christoph Lameter Signed-off-by: Joonsoo Kim Signed-off-by: Pekka Enberg Signed-off-by: Ben Hutchings --- Reading git-diff-tree failed