Commit de3083ec authored Sep 27, 2006 by Christoph Lameter Committed by Linus Torvalds Sep 27, 2006

[PATCH] slab: fix kmalloc_node applying memory policies if nodeid == numa_node_id()



kmalloc_node() falls back to ___cache_alloc() under certain conditions and
at that point memory policies may be applied redirecting the allocation
away from the current node.  Therefore kmalloc_node(...,numa_node_id()) or
kmalloc_node(...,-1) may not return memory from the local node.

Fix this by doing the policy check in __cache_alloc() instead of
____cache_alloc().

This version here is a cleanup of Kiran's patch.

- Tested on ia64.
- Extra material removed.
- Consolidate the exit path if alternate_node_alloc() returned an object.

[akpm@osdl.org: warning fix]
Signed-off-by: Alok N Kataria <alok.kataria@calsoftinc.com>
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Shai Fultheim <shai@scalex86.org>
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

parent 0fd0e6b0

mm/slab.c

+9 −10

Original line number	Diff line number	Diff line
		@@ -3028,14 +3028,6 @@ static inline void ____cache_alloc(struct kmem_cache cachep, gfp_t flags)
		void *objp;
		struct array_cache *ac;

		#ifdef CONFIG_NUMA
		if (unlikely(current->flags & (PF_SPREAD_SLAB \| PF_MEMPOLICY))) {
		objp = alternate_node_alloc(cachep, flags);
		if (objp != NULL)
		return objp;
		}
		#endif

		check_irq_off();
		ac = cpu_cache_get(cachep);
		if (likely(ac->avail)) {
		@@ -3053,11 +3045,18 @@ static __always_inline void __cache_alloc(struct kmem_cache cachep,
		gfp_t flags, void *caller)
		{
		unsigned long save_flags;
		void *objp;
		void *objp = NULL;

		cache_alloc_debugcheck_before(cachep, flags);

		local_irq_save(save_flags);

		#ifdef CONFIG_NUMA
		if (unlikely(current->flags & (PF_SPREAD_SLAB \| PF_MEMPOLICY)))
		objp = alternate_node_alloc(cachep, flags);
		#endif

		if (!objp)
		objp = ____cache_alloc(cachep, flags);
		local_irq_restore(save_flags);
		objp = cache_alloc_debugcheck_after(cachep, flags, objp,