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From: Peter Zijlstra <peterz@infradead.org>
To: tim <xiejingfeng@linux.alibaba.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>,
	Ingo Molnar <mingo@redhat.com>,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] psi:fix divide by zero in psi_update_stats
Date: Fri, 8 Nov 2019 10:31:36 +0100	[thread overview]
Message-ID: <20191108093136.GI4114@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <C377A5F1-F86F-4A27-966F-0285EC6EA934@linux.alibaba.com>

On Fri, Nov 08, 2019 at 03:33:24PM +0800, tim wrote:
> In psi_update_stats, it is possible that period has value like
> 0xXXXXXXXX00000000 where the lower 32 bit is 0, then it calls div_u64 which

How can this happen? Is that a valid case or should we be avoiding that?


  reply	other threads:[~2019-11-08  9:31 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-11-08  7:33 [PATCH] psi:fix divide by zero in psi_update_stats tim
2019-11-08  9:31 ` Peter Zijlstra [this message]
2019-11-08  9:49   ` Jingfeng Xie
2019-11-08 10:05     ` Peter Zijlstra
2019-11-12 15:41 ` Johannes Weiner
2019-11-12 15:48   ` Johannes Weiner
2019-11-12 16:08     ` Johannes Weiner
2019-11-12 17:27       ` Suren Baghdasaryan
2019-11-29  6:37       ` Jingfeng Xie
2019-11-30  1:41         ` Suren Baghdasaryan
2019-11-12 18:33   ` Suren Baghdasaryan

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