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From: Linh Dang <linhd@nortelnetworks.com>
Date: Wed, 25 Aug 2004 08:46:32 -0400
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Subject: Re: Bottom halves being disabled
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David Woodhouse <dwmw2@infradead.org> wrote:

> On Wed, 2004-08-25 at 06:48 -0400, Linh Dang wrote:
>> reduce latency with preemptable kernel. I've tried that. In my test
>> I hammered jffs2 pretty hard (for typical flash usage, no kernel
>> compilation here) and everything still seemed ok.
>
> Show numbers.

On my card (AMD Am29LV640 NOR flash), preemption was often disabled
for 450usecs in cfi_cmdset_002.c's do_read_onechip().

using semaphore instead of spin_lock, preemption would NOT be disabled
at all!

Btw, JFFS2 is great!

-- 
Linh Dang