Are workqueues cumulative?

greplinux · 04-08-2008, 10:31 PM

Hi All,

I have a question regarding workqueues. I read that tasklets can be eliminated by workqueues. And I would like to know whether they are cumulative or not. In other words what happens when a workqueue which is scheduled already is rescheduled before it get a chance to run for the first schedule.

Thanks,
Grep

sundialsvcs · 04-09-2008, 11:11 PM

The essential idea behind a workqueue is that in most cases you don't need a bunch of individual tasklets lying around just to handle "delayed work." What is done instead is to add them to a queue that is serviced by a kernel thread which exists for this purpose.

This accomplishes the essential purpose ("delayed work") in a very simple way.

In the case that you describe, there won't be any problem or conflict. When work is scheduled on a queue (no matter how many redundant times), it will be serviced "real soon now, somewhere."

greplinux · 04-10-2008, 11:17 PM

Hi Sun,

Thanks for your reply. Sorry that i still have some doubts after your reply. Let me make things clear.

For tasklets, if a tasklet is scheduled again ,before it gets a chance to run for the first schedule ultimately they will run only once not twice for two schedule.

Is that the same for workqueues ? What i interpret from your response is, this is not same for workqueues. Is that right buddy?

Sorry again, for not able to get what i need from your answer.

Thanks,
Greplinux

greplinux · 04-15-2008, 08:27 PM

Hi,

I have an update regarding this one. It is not possible to queue the same work more than once in a queue (ie) If a work is queued and it is not possible to queue the same work another time before it gets a chance to run . I hope this will bring an end to my dilemma,since here no cumulative kinda of thing is involved.

Any more information will be appreciated.

Thanks,
Grep.