linux-kernel - Re: [PATCH] xen-blkback: allocate list of pending reqs in small chunks

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 26 Apr 2013 15:47:40 +0100
From:	David Vrabel <david.vrabel@...rix.com>
To:	Roger Pau Monne <roger.pau@...rix.com>
CC:	"xen-devel@...ts.xen.org" <xen-devel@...ts.xen.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>
Subject: Re: [PATCH] xen-blkback: allocate list of pending reqs in small chunks

On 26/04/13 14:45, Roger Pau Monne wrote:
> Allocate pending requests in smaller chunks instead of allocating them
> all at the same time.
> 
> This change also removes the global array of pending_reqs, it is no
> longer necessay.
> 
> Variables related to the grant mapping have been grouped into a struct
> called "grant_page", this allows to allocate them in smaller chunks,
> and also improves memory locality.
> 
[...]
> diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c
> index afab208..2841c0f 100644
> --- a/drivers/block/xen-blkback/xenbus.c
> +++ b/drivers/block/xen-blkback/xenbus.c
> @@ -127,22 +128,53 @@ static struct xen_blkif *xen_blkif_alloc(domid_t domid)
>         blkif->free_pages_num = 0;
>         atomic_set(&blkif->persistent_gnt_in_use, 0);
> 
> -       blkif->pending_reqs = kcalloc(XEN_BLKIF_REQS,
> -                                     sizeof(blkif->pending_reqs[0]),
> -                                     GFP_KERNEL);
> -       if (!blkif->pending_reqs) {
> -               kmem_cache_free(xen_blkif_cachep, blkif);
> -               return ERR_PTR(-ENOMEM);
> -       }
>         INIT_LIST_HEAD(&blkif->pending_free);
> +
> +       pr_alert("sizeof req: %lu\n", sizeof(*req));

Stray pr_alert() here.

Looks good otherwise.

Reviewed-by: David Vrabel <david.vrabel@...rix.com>

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