From: Philippe Gerum <rpm@xenomai.org>
To: Giulio Moro <giulio@bela.io>
Cc: Xenomai <xenomai@lists.linux.dev>
Subject: Re: evl. event and mutex
Date: Wed, 18 Feb 2026 09:50:16 +0100 [thread overview]
Message-ID: <87v7fuxwon.fsf@xenomai.org> (raw)
In-Reply-To: <facf1a8f-697a-453d-758c-acaa2c92c804@bela.io> (Giulio Moro's message of "Tue, 17 Feb 2026 15:28:21 -0500")
Giulio Moro <giulio@bela.io> writes:
> Hi everyone,
> I am trying to use evl_event and evl_mutex so that two threads can signal each other when either needs work from the other, so they each need to call evl_signal_event() and evl_wait_event(). The first thread to call evl_wait_event() seems to correctly drop the mutex, thus unlocking the second thread. When the second thread signals the condition variable (while holding the mutex) and then calls evl_wait_event(), thus implicitly dropping the mutex, the first thread is, unexpectedly, not restarted. I noticed that if a third thread acquires and then releases the lock (without touching the condition variable), then the first thread is restarted. This sounds like a bug?
>
It is, please pick this commit (on v6.18.y, backported to v6.1.y-cip and v6.12.y):
https://gitlab.com/Xenomai/xenomai4/linux-evl/-/commit/c02e718dda07cfa1db079450d352f62b32702c55
--
Philippe.
next prev parent reply other threads:[~2026-02-18 8:50 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-02-17 20:28 evl. event and mutex Giulio Moro
2026-02-18 8:50 ` Philippe Gerum [this message]
2026-02-19 13:28 ` Giulio Moro
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