Re: [RFC][PATCH 1/2] sched: Extended scheduler time slice
From: Steven Rostedt
Date: Sun Feb 02 2025 - 17:29:33 EST
On Sun, 2 Feb 2025 07:22:08 +0000
Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote:
> On Sat, Feb 01, 2025 at 10:22:08PM -0500, Steven Rostedt wrote:
> > And before seeing Peter's use of yield(), I was reluctant to use it for
> > the very same reasons you mentioned above. In my test programs, I was
> > simply using getuid(), as that was one of the quickest syscalls.
>
> Is getuid() guaranteed to issue a syscall? It feels like the kind of
> information that a tricksy libc could cache. Traditionally, I think
> we've used getppid() as the canonical "very cheap syscall" as no layer
> can cache that information.
Maybe that was what I used. Can't remember. And I think I even open
coded it using syscall() to not even rely on glibc.
-- Steve