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Date: Wed, 29 Jan 2025 18:23:03 +0100
From: Frederic Weisbecker <frederic@kernel.org>
To: Rik van Riel <riel@surriel.com>
Cc: "Paul E. McKenney" <paulmck@kernel.org>,
	Matthew Wilcox <willy@infradead.org>,
	Qi Zheng <zhengqi.arch@bytedance.com>,
	Peter Zijlstra <peterz@infradead.org>,
	David Hildenbrand <david@redhat.com>,
	kernel test robot <oliver.sang@intel.com>, oe-lkp@lists.linux.dev,
	lkp@intel.com, linux-kernel@vger.kernel.org,
	Andrew Morton <akpm@linux-foundation.org>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	Andy Lutomirski <luto@kernel.org>,
	Catalin Marinas <catalin.marinas@arm.com>,
	David Rientjes <rientjes@google.com>,
	Hugh Dickins <hughd@google.com>, Jann Horn <jannh@google.com>,
	Lorenzo Stoakes <lorenzo.stoakes@oracle.com>,
	Mel Gorman <mgorman@suse.de>, Muchun Song <muchun.song@linux.dev>,
	Peter Xu <peterx@redhat.com>, Will Deacon <will@kernel.org>,
	Zach O'Keefe <zokeefe@google.com>,
	Dan Carpenter <dan.carpenter@linaro.org>,
	Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
Subject: Re: [linus:master] [x86] 4817f70c25: stress-ng.mmapaddr.ops_per_sec
 63.0% regression
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In-Reply-To: <13f95d28b0110a87b492d46e9810af51b33a23c8.camel@surriel.com>

Le Wed, Jan 29, 2025 at 11:57:19AM -0500, Rik van Riel a écrit :
> On Wed, 2025-01-29 at 17:53 +0100, Frederic Weisbecker wrote:
> > Le Wed, Jan 29, 2025 at 08:36:12AM -0800, Paul E. McKenney a écrit :
> > > 
> > > So it won't prevent RCU callbacks from being invoked.
> > > 
> > > It *will* ensure that only a finite number of RCU callbacks get
> > > invoked.
> > > For some perhaps rather large value of "finite".
> > > 
> > > Does that help, or is more required?
> > 
> > I don't fully understand the issue either but would spin_lock_bh()
> > help?
> 
> Was that a jinx, or an ack to that latest patch? ;)

Probably both :-)

> 
> -- 
> All Rights Reversed.