On Tue, May 08, 2007 at 06:05:17PM +0400, Oleg Nesterov wrote: > On 05/08, Jarek Poplawski wrote: > > > > On Tue, May 08, 2007 at 04:31:02PM +0400, Oleg Nesterov wrote: > > > > > > I thought about adding such a parameter, and I don't like this. This is > > > a matter of taste, of course, but _imho_ this uglifies the code. > > > > > > In any case, unless we do completely different patch, the sequence should > > > be > > > > > > del_timer() - a pending timer is the most common case > > > > > > test_and_set_bit(WORK_STRUCT_PENDING) - the work is idle > > > > > > try-to-steal-the-queued-work > > > > > > This is what we are doing now. > > > > I simply don't like to call del_timer(), where not needed, but maybe > > it's not so expensive and we can afford it... > > But this is the most common case, that was my point.
And I agree it should start... > > Look, we can add > > if (!get_wq_data(work)) > /* it was never queued */ > return; > > at the very start of cancel_xxx() functions. This will optimize out > del_timer + try_to_grab_pending() _sometimes_. Should we do this? > I don't think so. I think it is better to save a couple of bytes > from i-cache, but not to try to optimize the unlikely case. But the most of our test is already done in test_and_set_bit. I think it's more about taste, so let's forget... > > > So, we should either return 0, or add BUG_ON(!cwq). > > > > ...And you prefer endless loop. Seems brave! > > No, no, the loop won't be endless. Why do you think so? We spin until the > timer > is started, or until the work is queued. Probably you are right - I was afraid about some inactive work with no timer to come. So, I think this all looks fine, and maybe one more needless ack won't do any harm here: Acked-by: Jarek Poplawski <[EMAIL PROTECTED]> - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
