From: Steffen Klassert Subject: Re: [PATCH] padata: make the sequence counter an atomic_t Date: Tue, 8 Oct 2013 14:08:24 +0200 Message-ID: <20131008120824.GN7660@secunet.com> References: <1380721245-5215-1-git-send-email-mathias.krause@secunet.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-crypto@vger.kernel.org To: Mathias Krause , Herbert Xu Return-path: Received: from a.mx.secunet.com ([195.81.216.161]:60660 "EHLO a.mx.secunet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752569Ab3JHMI0 (ORCPT ); Tue, 8 Oct 2013 08:08:26 -0400 Content-Disposition: inline In-Reply-To: <1380721245-5215-1-git-send-email-mathias.krause@secunet.com> Sender: linux-crypto-owner@vger.kernel.org List-ID: On Wed, Oct 02, 2013 at 03:40:45PM +0200, Mathias Krause wrote: > Using a spinlock to atomically increase a counter sounds wrong -- we've > atomic_t for this! > > Also move 'seq_nr' to a different cache line than 'lock' to reduce cache > line trashing. This has the nice side effect of decreasing the size of > struct parallel_data from 192 to 128 bytes for a x86-64 build, e.g. > occupying only two instead of three cache lines. > > Those changes results in a 5% performance increase on an IPsec test run > using pcrypt. > > Btw. the seq_lock spinlock was never explicitly initialized -- one more > reason to get rid of it. > > Signed-off-by: Mathias Krause Acked-by: Steffen Klassert Herbert can you take this one?