lkml.org 
[lkml]   [2001]   [Apr]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: softirq buggy [Re: Serial port latency]
Date
Hello!

> But with a huge overhead. I'd prefer to call it directly from within the
> idle functions, the overhead of schedule is IMHO too high.


+ if (current->need_resched) {
+ return 0;
^^^^^^^^
+ }
+ if (softirq_active(smp_processor_id()) & softirq_mask(smp_processor_id())) {
+ do_softirq();
+ return 0;
^^^^^^^^^
You return one value in both casesand I decided it means "schedule". 8)
Apparently you meaned return 1 in the first case. 8)

But in this case it becomes wrong. do_softirq() can raise need_reshed
and moreover irqs arrive during it. Order of check should be different.


BTW what's about overhead... I suspect it is _lower_ in the case
of schedule(). In the case of networking at least, when softirq
most likely wakes some socket.

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

\
 
 \ /
  Last update: 2005-03-22 13:24    [W:0.055 / U:40.412 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site