Re: [PATCH] doc: add note on usleep_range range

2017-01-12 Thread Pavel Machek
On Wed 2017-01-11 08:50:07, Nicholas Mc Guire wrote: > On Tue, Jan 10, 2017 at 10:25:29PM +0100, Pavel Machek wrote: > > Hi! > > > > > > "to have zero jitter" at least. I believe it is "does not". > > > > > > > > I don't see how atomic vs. non-atomic context makes difference. There > > > > are so

Re: [PATCH] doc: add note on usleep_range range

2017-01-11 Thread Nicholas Mc Guire
On Tue, Jan 10, 2017 at 10:25:29PM +0100, Pavel Machek wrote: > Hi! > > > > "to have zero jitter" at least. I believe it is "does not". > > > > > > I don't see how atomic vs. non-atomic context makes difference. There > > > are sources of jitter that affect atomic context... > > > > The relevanc

Re: [PATCH] doc: add note on usleep_range range

2017-01-10 Thread Pavel Machek
Hi! > > "to have zero jitter" at least. I believe it is "does not". > > > > I don't see how atomic vs. non-atomic context makes difference. There > > are sources of jitter that affect atomic context... > > The relevance is that while there is jitter in atomic context it can > be quite small (dep

Re: [PATCH] doc: add note on usleep_range range

2017-01-07 Thread Nicholas Mc Guire
On Tue, Dec 27, 2016 at 10:56:26PM +0100, Pavel Machek wrote: > On Tue 2016-12-13 04:58:43, Nicholas Mc Guire wrote: > > useleep_range() with a delta of 0 makes no sense and only prevents the > > timer subsystem from optimizing interrupts. As any user of usleep_range() > > is in non-atomic context

Re: [PATCH] doc: add note on usleep_range range

2016-12-27 Thread Pavel Machek
On Tue 2016-12-13 04:58:43, Nicholas Mc Guire wrote: > useleep_range() with a delta of 0 makes no sense and only prevents the > timer subsystem from optimizing interrupts. As any user of usleep_range() > is in non-atomic context the timer jitter is in the range of 10s of > microseconds anyway. >

Re: [PATCH] doc: add note on usleep_range range

2016-12-13 Thread Joe Perches
On Wed, 2016-12-14 at 00:37 +, Nicholas Mc Guire wrote: > On Tue, Dec 13, 2016 at 04:27:32PM -0800, Joe Perches wrote: > > a, On Tue, 2016-12-13 at 09:19 +, Nicholas Mc Guire wrote: > > > On Tue, Dec 13, 2016 at 11:10:50AM +0200, Jani Nikula wrote: > > > > On Tue, 13 Dec 2016, Nicholas Mc G

Re: [PATCH] doc: add note on usleep_range range

2016-12-13 Thread Nicholas Mc Guire
On Tue, Dec 13, 2016 at 04:27:32PM -0800, Joe Perches wrote: > a, On Tue, 2016-12-13 at 09:19 +, Nicholas Mc Guire wrote: > > On Tue, Dec 13, 2016 at 11:10:50AM +0200, Jani Nikula wrote: > > > On Tue, 13 Dec 2016, Nicholas Mc Guire wrote: > > > > useleep_range() with a delta of 0 makes no sens

Re: [PATCH] doc: add note on usleep_range range

2016-12-13 Thread Joe Perches
a, On Tue, 2016-12-13 at 09:19 +, Nicholas Mc Guire wrote: > On Tue, Dec 13, 2016 at 11:10:50AM +0200, Jani Nikula wrote: > > On Tue, 13 Dec 2016, Nicholas Mc Guire wrote: > > > useleep_range() with a delta of 0 makes no sense and only prevents the > > > timer subsystem from optimizing interru

Re: [PATCH] doc: add note on usleep_range range

2016-12-13 Thread Nicholas Mc Guire
On Tue, Dec 13, 2016 at 01:05:12PM +0100, Julia Lawall wrote: > > > On Tue, 13 Dec 2016, Nicholas Mc Guire wrote: > > > On Tue, Dec 13, 2016 at 11:10:50AM +0200, Jani Nikula wrote: > > > On Tue, 13 Dec 2016, Nicholas Mc Guire wrote: > > > > useleep_range() with a delta of 0 makes no sense and o

Re: [PATCH] doc: add note on usleep_range range

2016-12-13 Thread Julia Lawall
On Tue, 13 Dec 2016, Nicholas Mc Guire wrote: > On Tue, Dec 13, 2016 at 11:10:50AM +0200, Jani Nikula wrote: > > On Tue, 13 Dec 2016, Nicholas Mc Guire wrote: > > > useleep_range() with a delta of 0 makes no sense and only prevents the > > > timer subsystem from optimizing interrupts. As any us

Re: [PATCH] doc: add note on usleep_range range

2016-12-13 Thread Jani Nikula
On Tue, 13 Dec 2016, Nicholas Mc Guire wrote: > I fully agree - without automation it is almost usless > the coccinelle spatch is a seperate patch and it is tested butnot yet > submitted. Good, good! Sorry for the noise. BR, Jani. -- Jani Nikula, Intel Open Source Technology Center -- To unsu

Re: [PATCH] doc: add note on usleep_range range

2016-12-13 Thread Nicholas Mc Guire
On Tue, Dec 13, 2016 at 11:10:50AM +0200, Jani Nikula wrote: > On Tue, 13 Dec 2016, Nicholas Mc Guire wrote: > > useleep_range() with a delta of 0 makes no sense and only prevents the > > timer subsystem from optimizing interrupts. As any user of usleep_range() > > is in non-atomic context the tim

Re: [PATCH] doc: add note on usleep_range range

2016-12-13 Thread Jani Nikula
On Tue, 13 Dec 2016, Nicholas Mc Guire wrote: > useleep_range() with a delta of 0 makes no sense and only prevents the > timer subsystem from optimizing interrupts. As any user of usleep_range() > is in non-atomic context the timer jitter is in the range of 10s of > microseconds anyway. > > This

[PATCH] doc: add note on usleep_range range

2016-12-12 Thread Nicholas Mc Guire
useleep_range() with a delta of 0 makes no sense and only prevents the timer subsystem from optimizing interrupts. As any user of usleep_range() is in non-atomic context the timer jitter is in the range of 10s of microseconds anyway. This adds a note making it clear that a range of 0 is a bad ide