Re: [PATCH] slab: minor cleanup to kmem_cache_alloc_node

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Pekka J Enberg a écrit :
This patch gets rid of one if-else statement by moving current node allocation
check at the beginning of kmem_cache_alloc_node().


Are you sure this is valid ?
What about preemption ?
The "if (nodeid == numa_node_id())" check was done with IRQ off, and you want do do it with IRQ on.

Signed-off-by: Pekka Enberg <[email protected]>
---

 slab.c |    7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/mm/slab.c b/mm/slab.c
index 7f80ec3..a05bbfe 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -2881,7 +2881,7 @@ void *kmem_cache_alloc_node(kmem_cache_t
 	unsigned long save_flags;
 	void *ptr;
- if (nodeid == -1)
+	if (nodeid == -1 || nodeid == numa_node_id())

<Imagine preemption here, and thread migrated to another NUMA node.>

 		return __cache_alloc(cachep, flags);
if (unlikely(!cachep->nodelists[nodeid])) {
@@ -2892,10 +2892,7 @@ void *kmem_cache_alloc_node(kmem_cache_t
cache_alloc_debugcheck_before(cachep, flags);
 	local_irq_save(save_flags);
-	if (nodeid == numa_node_id())
-		ptr = ____cache_alloc(cachep, flags);
-	else
-		ptr = __cache_alloc_node(cachep, flags, nodeid);
+	ptr = __cache_alloc_node(cachep, flags, nodeid);
 	local_irq_restore(save_flags);
 	ptr = cache_alloc_debugcheck_after(cachep, flags, ptr, __builtin_return_address(0));

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux