Re: [Xenomai] EINTR in notifier.c (mercury)

[Philippe Gerum <rpm@xenomai.org>]

On 03/31/2014 12:34 PM, Matthias Schneider wrote:
> Hi all,
>
>
> still working on thread suspension in mercury, I noticed that some
>
> threadobj_suspend() and threadobj_resume() calls seemed not to have the desired
>
> effect. Analyzing the issue, I found out that sometimes the read operations on
> the pipe in notifier_wait() seem to return with EINTR, especially in
> heavily loaded systems. Restarting the read system call in that case made
> thread suspension a lot more reliable in my case.
>
> I have attached a patch adding loops to deal with the EINTR situation in all
>
> read and write operations of notifier.c.
>

Agreed, we are reading from a deemed slow device. However, the patch is 
wrong in testing the first loop condition (notifier_sighandler). In 
addition, we don't need two nested loops, a single one would suffice 
with a proper test condition.

Nitpicking: please move all variable declarators to the outer local 
declaration block, and avoid compound braces for single-statement blocks.

-- 
Philippe.