Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753327AbbKZJMS (ORCPT ); Thu, 26 Nov 2015 04:12:18 -0500 Received: from mail-wm0-f52.google.com ([74.125.82.52]:34074 "EHLO mail-wm0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752873AbbKZJMG (ORCPT ); Thu, 26 Nov 2015 04:12:06 -0500 Date: Thu, 26 Nov 2015 10:12:01 +0100 From: Ingo Molnar To: Seth Jennings Cc: Thomas Gleixner , Ingo Molnar , Peter Anvin , Daniel J Blueman , Yinghai Lu , x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] x86: mm: clean up probe_memory_block_size() Message-ID: <20151126091201.GB30403@gmail.com> References: <1448396191-27996-1-git-send-email-sjennings@variantweb.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1448396191-27996-1-git-send-email-sjennings@variantweb.net> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1969 Lines: 59 * Seth Jennings wrote: > The cumulative effect of bdee237c and 982792c7 is some pretty convoluted > code. This commit has no (intended) functional change; just seeks to > simplify and make the code more understandable. > > The whole section with the "tail size" doesn't seem to be reachable, > since both the >= 64GB and < 64GB case return, so it was removed. > > This commit also adds code back for the UV case since it seemed to just > go away without reason in bdee237c and might lead to unexpected change > in behavior. > > Signed-off-by: Seth Jennings > --- > arch/x86/mm/init_64.c | 22 ++++++---------------- > 1 file changed, 6 insertions(+), 16 deletions(-) > > diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c > index ec081fe..a83c470 100644 > --- a/arch/x86/mm/init_64.c > +++ b/arch/x86/mm/init_64.c > @@ -52,6 +52,7 @@ > #include > #include > #include > +#include > #include > > #include "mm_internal.h" > @@ -1194,26 +1195,15 @@ int kern_addr_valid(unsigned long addr) > > static unsigned long probe_memory_block_size(void) > { > + unsigned long bz = MIN_MEMORY_BLOCK_SIZE; > > + /* if system is UV or has 64GB of RAM or more, use large blocks */ > + if (is_uv_system() || ((max_pfn << PAGE_SHIFT) >= (64UL << 30))) { > pr_info("Using 2GB memory block size for large-memory system\n"); > + bz = 2UL << 30; /* 2GB */ > } > > + pr_debug("memory block size : %ldMB\n", bz >> 20); > > return bz; > } So why keep 'bz' at all? Just return with the right value and be done with it. 'bz' is just an unnecessary confusion factor. Thanks, Ingo -- 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/