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Wed, 12 Mar 2025 00:56:32 -0700 (PDT) Received: by grain.localdomain (Postfix, from userid 1000) id 0AB565A0044; Wed, 12 Mar 2025 10:56:32 +0300 (MSK) Date: Wed, 12 Mar 2025 10:56:31 +0300 From: Cyrill Gorcunov To: Frederic Weisbecker Cc: Thomas Gleixner , LKML , Anna-Maria Behnsen , Benjamin Segall , Eric Dumazet , Andrey Vagin , Pavel Tikhomirov , Peter Zijlstra Subject: Re: [patch V3a 17/18] posix-timers: Provide a mechanism to allocate a given timer ID Message-ID: References: <20250308155501.391430556@linutronix.de> <20250308155624.526740902@linutronix.de> <87msdrz0i9.ffs@tglx> <87jz8vz0en.ffs@tglx> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/2.2.14 (2025-02-20) On Tue, Mar 11, 2025 at 11:32:58PM +0100, Frederic Weisbecker wrote: ... > > > > Recreating two timers with IDs 1000000 and 2000000 takes 1.5 seconds with > > the create/delete method. With the prctl() it takes 3 microseconds. > > > > Signed-off-by: Thomas Gleixner > > Reviewed-by: Frederic Weisbecker One thing which just popped up in my head -- this interface may be used not only by criu but any application which wants to create timer with specified id (hell know why, but whatever). As far as I understand we don't provide an interface to _read_ this property, don't we? Thus criu will restore such application which already has this bit set incorrectly. Cyrill