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Re: Race unlocking-locking mutex
- From: "Carlos O'Donell" <carlos at redhat dot com>
- To: Godmar Back <godmar at gmail dot com>, Rich Felker <dalias at aerifal dot cx>
- Cc: "Carlos O'Donell" <carlos at systemhalted dot org>, David Ahern <dsahern at gmail dot com>, "libc-help at sourceware dot org" <libc-help at sourceware dot org>
- Date: Fri, 13 Sep 2013 15:19:48 -0400
- Subject: Re: Race unlocking-locking mutex
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On 09/13/2013 01:33 PM, Godmar Back wrote:
> The standard says:
> "The need to hold spin lock overhead to an absolute minimum also
> makes it impossible to provide guarantees against starvation similar
> to those provided for mutexes or read-write locks."
> What starvation guarantees are they talking about? I thought it meant
> that an implementation is required to use a FIFO policy if multiple
> SCHED_RR/SCHED_FIFO threads of *equal* priority are queued on a
> contended lock.
> But I also haven't been able to find it explicitly saying so.
I've never seen any guarantees against starvation.
Including you here to pick your brain. Has POSIX ever guaranteed
that mutexes or read-write locks are free of starvation?
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