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From: zhangxiao <xiao.zhang@windriver.com>
To: neilb@suse.de
Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: The DM_BUFIO_HASH_BITS is defined as 20, any plan to make it flexible?
Date: Tue, 2 Dec 2014 16:32:14 +0800	[thread overview]
Message-ID: <547D790E.3070803@windriver.com> (raw)

Hi NeilBrown,

See drivers/md/dm-bufio.c as below:
   50 /*
   51  * Buffer hash
   52  */
   53 #define DM_BUFIO_HASH_BITS      20
   54 #define DM_BUFIO_HASH(block) \
   55         ((((block) >> DM_BUFIO_HASH_BITS) ^ (block)) & \
   56          ((1 << DM_BUFIO_HASH_BITS) - 1))
"drivers/md/dm-bufio.c" 1854L, 45375C 


DM_BUFIO_HASH_BITS was defined as 20 and it maybe not fit for some
use case with limited resources. Do we have any plan to make it more
flexible? Like module parameter or something else?

Thanks
Xiao

             reply	other threads:[~2014-12-02  8:32 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-12-02  8:32 zhangxiao [this message]
2014-12-02  8:36 ` The DM_BUFIO_HASH_BITS is defined as 20, any plan to make it flexible? NeilBrown
2014-12-02  8:40   ` zhangxiao
  -- strict thread matches above, loose matches on Subject: below --
2014-12-02  8:43 zhangxiao
2014-12-02 14:00 ` Mike Snitzer
2014-12-03 14:19   ` [dm-devel] " Joe Thornber
2014-12-03 16:17     ` Mike Snitzer

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