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: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-Id: <20100915093253.798d5cdf.rdunlap@xenotime.net>
Date:	Wed, 15 Sep 2010 09:32:53 -0700
From:	Randy Dunlap <rdunlap@...otime.net>
To:	Namhyung Kim <namhyung@...il.com>
Cc:	Jiri Kosina <trivial@...nel.org>, linux-kernel@...r.kernel.org
Subject: Re: [PATCH UPDATED 1/2] ida: document IDA_BITMAP_LONGS calculation

On Thu, 16 Sep 2010 01:30:19 +0900 Namhyung Kim wrote:

> IDA_BITMAP_LONGS value is calculated take into account struct ida_bitmap
> not to waste memory space. Comment it.
> 
> Signed-off-by: Namhyung Kim <namhyung@...il.com>
> Acked-by: Tejun Heo <tj@...nel.org>

Acked-by: Randy Dunlap <rdunlap@...otime.net>

Thanks.


> ---
>  include/linux/idr.h |    5 ++++-
>  1 files changed, 4 insertions(+), 1 deletions(-)
> 
> diff --git a/include/linux/idr.h b/include/linux/idr.h
> index e968db7..3f4b718 100644
> --- a/include/linux/idr.h
> +++ b/include/linux/idr.h
> @@ -117,10 +117,13 @@ void idr_init(struct idr *idp);
>  /*
>   * IDA - IDR based id allocator, use when translation from id to
>   * pointer isn't necessary.
> + *
> + * IDA_BITMAP_LONGS is calculated to be one less to accommodate
> + * ida_bitmap->nr_busy so that the whole struct fits in 128 bytes.
>   */
>  #define IDA_CHUNK_SIZE		128	/* 128 bytes per chunk */
> -#define IDA_BITMAP_LONGS	(128 / sizeof(long) - 1)
> -#define IDA_BITMAP_BITS		(IDA_BITMAP_LONGS * sizeof(long) * 8)
> +#define IDA_BITMAP_LONGS	(IDA_CHUNK_SIZE / sizeof(long) - 1)
> +#define IDA_BITMAP_BITS 	(IDA_BITMAP_LONGS * sizeof(long) * 8)
>  
>  struct ida_bitmap {
>  	long			nr_busy;
> -- 


---
~Randy
*** Remember to use Documentation/SubmitChecklist when testing your code ***
--
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/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ