From: Philip Balister <philip@balister.org>
To: "linux-omap@vger.kernel.org" <linux-omap@vger.kernel.org>
Subject: Change in mmap driver performance from 2..6.38 to 2.6.39
Date: Mon, 11 Jul 2011 10:21:49 -0400 [thread overview]
Message-ID: <4E1B06FD.5090107@balister.org> (raw)
I have a device drier that uses a mmap'd section of memory to expose dma
buffers to user space.
(https://github.com/balister/linux-omap-philip/blob/e100-2.6.38/drivers/misc/usrp_e.c).
I have it running on the 2.6.38 and 2.6.39 kernel, but it looks like
read performance is much slower in the .39 version than the .28 version.
Does anyone know what changed between these two kernel versions and how
it might fix it?
Thanks,
Philip
next reply other threads:[~2011-07-11 14:28 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-07-11 14:21 Philip Balister [this message]
2011-07-11 14:42 ` Change in mmap driver performance from 2..6.38 to 2.6.39 Tony Lindgren
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