From mboxrd@z Thu Jan  1 00:00:00 1970
From: Florian Weimer <fweimer@redhat.com>
Subject: Re: extending wait4(2) or waitid(2) linux syscall
Date: Fri, 16 Nov 2018 11:26:50 +0100
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References: <20170420152051.568f2050.albert.aribaud@3adev.fr>
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	<20181115153008.GC2171@altlinux.org>
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	(Arnd Bergmann's message of "Thu, 15 Nov 2018 23:14:21 -0800")
To: Arnd Bergmann <arnd@arndb.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>, "Dmitry V. Levin" <ldv@altlinux.org>, Albert ARIBAUD <albert.aribaud@3adev.fr>, GNU C Library <libc-alpha@sourceware.org>, Linux API <linux-api@vger.kernel.org>
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* Arnd Bergmann:

> On Thu, Nov 15, 2018 at 7:38 AM <hpa@zytor.com> wrote:
>> On November 15, 2018 7:30:11 AM PST, "Dmitry V. Levin" <ldv@altlinux.org> wrote:
>> >On Thu, Nov 15, 2018 at 06:39:03AM -0800, Arnd Bergmann wrote:
>> >> On Thu, Nov 15, 2018 at 6:05 AM Dmitry V. Levin wrote:
>> >> > On Thu, Apr 20, 2017 at 03:20:51PM +0200, Albert ARIBAUD wrote:
>
>> >2. The time precision provided by struct rusage returned by wait4(2)
>> >and waitid(2) is too low for syscall time counting (strace -c) nowadays,
>> >this can be observing by running in a row a simple command like "strace -c
>> >pwd".
>> >
>> >The fix is to return a more appropriate structure than struct rusage
>> >by the new pwait6(2)/pwaitid(2) syscall mentioned above, where
>> >struct timeval is replaced with struct timespec or even struct
>> >timespec64.
>>
>> Arnd: w.r.t. our previous discussion, this would seem to justify going to timespec(64) for these kind of cases.
>
> Ok, and I assume we want the same layout for getrusage(2) then, right?

Or introduce something that covers FreeBSD's wait6 functionality as well
(resource usage by subprocesses of the subprocess).

Thanks,
Florian