From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sagi Grimberg Subject: Re: [PATCH] scsi: use sector_div instead of do_div Date: Tue, 24 Nov 2015 14:50:36 +0200 Message-ID: <56545D1C.6070509@dev.mellanox.co.il> References: <24882658.08y4bWL6tn@wuerfel> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <24882658.08y4bWL6tn@wuerfel> Sender: linux-kernel-owner@vger.kernel.org To: Arnd Bergmann , linux-scsi@vger.kernel.org Cc: jbottomley@odin.com, martin.petersen@oracle.com, nico@fluxnic.net, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org List-Id: linux-scsi@vger.kernel.org On 20/11/2015 18:38, Arnd Bergmann wrote: > do_div is the wrong way to divide a sector_t, as it is less > efficient when sector_t is 32-bit wide. With the upcoming > do_div optimizations, the kernel starts warning about this: > > drivers/scsi/scsi_debug.c: In function 'dif_store': > include/asm-generic/div64.h:207:28: warning: comparison of distinct pointer types lacks a cast > > This changes the code to use sector_div instead, which always > produces optimal code. > > Signed-off-by: Arnd Bergmann Reviewed-by: Sagi Grimberg From mboxrd@z Thu Jan 1 00:00:00 1970 From: sagig@dev.mellanox.co.il (Sagi Grimberg) Date: Tue, 24 Nov 2015 14:50:36 +0200 Subject: [PATCH] scsi: use sector_div instead of do_div In-Reply-To: <24882658.08y4bWL6tn@wuerfel> References: <24882658.08y4bWL6tn@wuerfel> Message-ID: <56545D1C.6070509@dev.mellanox.co.il> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 20/11/2015 18:38, Arnd Bergmann wrote: > do_div is the wrong way to divide a sector_t, as it is less > efficient when sector_t is 32-bit wide. With the upcoming > do_div optimizations, the kernel starts warning about this: > > drivers/scsi/scsi_debug.c: In function 'dif_store': > include/asm-generic/div64.h:207:28: warning: comparison of distinct pointer types lacks a cast > > This changes the code to use sector_div instead, which always > produces optimal code. > > Signed-off-by: Arnd Bergmann Reviewed-by: Sagi Grimberg