[resend][PATCH 2/3] mqueue: don't use kmalloc with KMALLOC_MAX_SIZE

From: kosaki . motohiro
Date: Fri Dec 09 2011 - 17:36:43 EST


From: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>

KMALLOC_MAX_SIZE is no good threshold. It is extream high and
problematic. Unfortunately, some silly drivers depend on and
we can't change it. but any new code don't use such extream
ugly high order allocations. It bring us awful fragmentation
issue and system slowdown.

Signed-off-by: KOSAKI Motohiro <mkosaki@xxxxxxxxxxxxxx>
Acked-by: Doug Ledford <dledford@xxxxxxxxxx>
Acked-by: Joe Korty <joe.korty@xxxxxxxx>
Cc: Amerigo Wang <amwang@xxxxxxxxxx>
Cc: Serge E. Hallyn <serue@xxxxxxxxxx>
Cc: Jiri Slaby <jslaby@xxxxxxx>
---
ipc/mqueue.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index c246c83..315f84f 100644
--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -151,7 +151,7 @@ static struct inode *mqueue_get_inode(struct super_block *sb,
info->attr.mq_msgsize = attr->mq_msgsize;
}
mq_msg_tblsz = info->attr.mq_maxmsg * sizeof(struct msg_msg *);
- if (mq_msg_tblsz > KMALLOC_MAX_SIZE)
+ if (mq_msg_tblsz > PAGE_SIZE)
info->messages = vmalloc(mq_msg_tblsz);
else
info->messages = kmalloc(mq_msg_tblsz, GFP_KERNEL);
@@ -275,7 +275,7 @@ static void mqueue_evict_inode(struct inode *inode)
spin_lock(&info->lock);
for (i = 0; i < info->attr.mq_curmsgs; i++)
free_msg(info->messages[i]);
- if (info->attr.mq_maxmsg * sizeof(struct msg_msg *) > KMALLOC_MAX_SIZE)
+ if (is_vmalloc_addr(info->messages))
vfree(info->messages);
else
kfree(info->messages);
--
1.7.1

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