Re: [PATCH] kernel/softirq.c: delete 'while' looping to improve alittle performance and beautify code

From: Chen Gang
Date: Wed Jun 12 2013 - 22:11:26 EST


On 06/10/2013 10:15 PM, Thomas Gleixner wrote:
> On Sun, 9 Jun 2013, Chen Gang wrote:
>> > After finish the internal 'while', need not test TASKLET_STATE_SCHED
>> > again, so looping back to outside 'while' is only for set_bit().
>> >
>> > When use 'if' and set_bit() instead of 'while', it will save at least
>> > one running conditional instruction, and also will be clearer for readers
>> > (although the binary size will be a little bigger).
> And by doing that you break the atomicity of test_and_set_bit. There
> is a good reason why this is an atomic operation and why the code is
> written as is.
>

OK, thanks. it is my fault (and also sorry for replying late).

>> > The related patch is "1da177e Linux-2.6.12-rc2"
> How is that patch related to the problem?

Because the modification since Linux-2.6.12-rc2.


Thanks.
--
Chen Gang

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