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Date:   Tue, 10 Aug 2021 15:14:28 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc:     Clark Williams <williams@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Dmitry Vyukov <dvyukov@google.com>,
        Andrey Konovalov <andreyknvl@gmail.com>,
        kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH PREEMPT_RT] kcov:  fix locking splat from
 kcov_remote_start()
Message-ID: <20210810151428.3e02d386@oasis.local.home>
In-Reply-To: <20210810095032.epdhivjifjlmbhp5@linutronix.de>
References: <20210809155909.333073de@theseus.lan>
        <20210810095032.epdhivjifjlmbhp5@linutronix.de>
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On Tue, 10 Aug 2021 11:50:32 +0200
Sebastian Andrzej Siewior <bigeasy@linutronix.de> wrote:

> - With lock kcov_remote_lock acquired there is a possible
>   hash_for_each_safe() and list_for_each() iteration. I don't know what
>   the limits are here but with a raw_spinlock_t it will contribute to
>   the maximal latency. 

Note, anyone having a kernel with KCOV compiled in, probably doesn't
care about latency ;-) It's like worrying about latency when lockdep is
complied in.

-- Steve