Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753739Ab2J2FGy (ORCPT ); Mon, 29 Oct 2012 01:06:54 -0400 Received: from casper.infradead.org ([85.118.1.10]:44095 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752760Ab2J2FGx (ORCPT ); Mon, 29 Oct 2012 01:06:53 -0400 Subject: Re: [PATCH] async_tx: use memchr_inv From: Vinod Koul To: Akinobu Mita Cc: vinod.koul@intel.com, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, Dan Williams In-Reply-To: <1351352973-3719-4-git-send-email-akinobu.mita@gmail.com> References: <1351352973-3719-1-git-send-email-akinobu.mita@gmail.com> <1351352973-3719-4-git-send-email-akinobu.mita@gmail.com> Content-Type: text/plain; charset="UTF-8" Date: Mon, 29 Oct 2012 10:23:43 +0530 Message-ID: <1351486423.7077.31.camel@vkoul-udesk3> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1205 Lines: 38 On Sun, 2012-10-28 at 00:49 +0900, Akinobu Mita wrote: > Use memchr_inv() to check the specified page is filled with zero. > > Signed-off-by: Akinobu Mita > Cc: Vinod Koul > Cc: Dan Williams > --- Looks fine to me, need Dan;s ack before applying > crypto/async_tx/async_xor.c | 4 +--- > 1 file changed, 1 insertion(+), 3 deletions(-) > > diff --git a/crypto/async_tx/async_xor.c b/crypto/async_tx/async_xor.c > index 154cc84..8ade0a0 100644 > --- a/crypto/async_tx/async_xor.c > +++ b/crypto/async_tx/async_xor.c > @@ -230,9 +230,7 @@ EXPORT_SYMBOL_GPL(async_xor); > > static int page_is_zero(struct page *p, unsigned int offset, size_t len) > { > - char *a = page_address(p) + offset; > - return ((*(u32 *) a) == 0 && > - memcmp(a, a + 4, len - 4) == 0); > + return !memchr_inv(page_address(p) + offset, 0, len); > } > > static inline struct dma_chan * -- Vinod Koul Intel Corp. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/