Messages in this thread | | | Date | Thu, 11 Dec 2008 13:31:53 +0100 | From | Pavel Machek <> | Subject | Re: [PATCH] kernel/freezer.c : Removing extra checking. |
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On Sat 2008-12-06 17:52:57, Rafael J. Wysocki wrote: > On Saturday, 6 of December 2008, Rakib Mullick wrote: > > On 12/6/08, Rafael J. Wysocki <rjw@sisk.pl> wrote: > > > On Saturday, 6 of December 2008, Rakib Mullick wrote: > > > > Impact: Reduces an extra checking. > > > > > > > > Following patch removes an extra checking. We can remove it since, the > > > > current task is frozen. If the current task is not frozen, then it > > > > will return from __else__ condition of freezing(current) check. So, > > > > the check becames unnecessary. It also reduces 32 bytes of text space > > > > on my x86 (32 bit) system. > > > > > > > > > What will happen with this patch applied when a task is woken up for some > > > reason other than thawing? > > thawing is usually used for woken up a frozzen process. Would you > > please tell me what are the other ways to woken up a frozzen process? > > Am I missing anything ? > > Well, in theory the process can be woken up for another reason.
...like pending signal...
> I don't have any particular examples in mind, but in this case the burden is > yours to show that it won't happen and to say why exactly you think so in the > changelog, because this is the very reason why the code has been written this > way in the first place. > > Thanks, > Rafael > > > > > > Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com> > > > > > > > > --- linux-2.6-orig/kernel/freezer.c 2008-12-05 19:53:45.000000000 +0600 > > > > +++ linux-2.6/kernel/freezer.c 2008-12-05 19:55:40.000000000 +0600 > > > > @@ -46,8 +46,6 @@ void refrigerator(void) > > > > > > > > for (;;) { > > > > set_current_state(TASK_UNINTERRUPTIBLE); > > > > - if (!frozen(current)) > > > > - break; > > > > schedule(); > > > > } > > > > pr_debug("%s left refrigerator\n", current->comm); > > >
Plus this looks like infinite loop after your change. Have you tested it?
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