Re: [PATCH 6/6] ipc/sem.c: make semctl(,,{GETNCNT,GETZCNT}) standard compliant

Andrew Morton
2014-05-19T22:46:42Z

On Sun, 18 May 2014 09:58:37 +0200 Manfred Spraul <manfred@colorfullife.com> wrote:

> SUSv4 clearly defines how semncnt and semzcnt must be calculated:
> A task waits on exactly one semaphore:
> The semaphore from the first operation in the sop array that cannot proceed.
>
> The Linux implementation never followed the standard, it tried to count all
> semaphores that might be the reason why a task sleeps.
>
> This patch fixes that.

What are the back-compatibility implications of this change?