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Date:   Wed, 10 Apr 2019 17:10:18 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Waiman Long <longman@redhat.com>
Cc:     Ingo Molnar <mingo@redhat.com>, Will Deacon <will.deacon@arm.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-kernel@vger.kernel.org, x86@kernel.org,
        Davidlohr Bueso <dave@stgolabs.net>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Tim Chen <tim.c.chen@linux.intel.com>
Subject: Re: [PATCH-tip v2 02/12] locking/rwsem: Implement lock handoff to
 prevent lock starvation
Message-ID: <20190410151018.GL7905@worktop.programming.kicks-ass.net>
References: <20190405192115.17416-1-longman@redhat.com>
 <20190405192115.17416-3-longman@redhat.com>
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On Fri, Apr 05, 2019 at 03:21:05PM -0400, Waiman Long wrote:
> +#define RWSEM_WAIT_TIMEOUT	((HZ - 1)/200 + 1)

Given the choices in HZ, the above seems fairly 'optimistic'.