Re: [PATCH 6/4] ipc/mqueue: don't use kmalloc(KMALLOC_MAX_SIZE)
From: Doug Ledford
Date: Wed Oct 26 2011 - 13:30:07 EST
----- Original Message -----
>
> 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 <kosaki.motohiro@xxxxxxxxx>
> Cc: Doug Ledford <dledford@xxxxxxxxxx>
> Cc: Amerigo Wang <amwang@xxxxxxxxxx>
> Cc: Serge E. Hallyn <serue@xxxxxxxxxx>
> Cc: Jiri Slaby <jslaby@xxxxxxx>
> Cc: Joe Korty <joe.korty@xxxxxxxx>
Acked-by: Doug Ledford <dledford@xxxxxxxxxx>
> ---
> ipc/mqueue.c | 4 ++--
> 1 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/ipc/mqueue.c b/ipc/mqueue.c
> index 229a5fb..91ca145 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);
> --
> 1.7.5.2
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe
> linux-kernel" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
>
--
Doug Ledford <dledford@xxxxxxxxxx>
GPG KeyID: 0E572FDD
http://people.redhat.com/dledford
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/