Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753997AbXLFDvl (ORCPT ); Wed, 5 Dec 2007 22:51:41 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752017AbXLFDve (ORCPT ); Wed, 5 Dec 2007 22:51:34 -0500 Received: from wr-out-0506.google.com ([64.233.184.232]:57657 "EHLO wr-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751974AbXLFDvd (ORCPT ); Wed, 5 Dec 2007 22:51:33 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references:x-google-sender-auth; b=GQc3o6bUmavWz+H8rC7bTY9NBHilg3QM0ne2mUoX8a1cx9Yjtvh6GBiRI6N8EMiUZmgh6MbvYYr4sboWZDHW7bArpAhU5nNeRTfed4BvrmjrCcpNMN38qpv5GkWT+WEUEIsTeac0qqwWVsjXfeLrYI2JzUcKWTEupsZoQ/2UM+s= Message-ID: <9c9fda240712051951w28aae15dle08279f8cc329e95@mail.gmail.com> Date: Thu, 6 Dec 2007 12:51:31 +0900 From: "Kyungmin Park" To: "Jared Hulbert" Subject: Re: solid state drive access and context switching Cc: "Alan Cox" , "Chris Friesen" , linux-kernel@vger.kernel.org In-Reply-To: <6934efce0712051401x2b137420hb04f971e1ca2cbf6@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <47548BF4.3010907@nortel.com> <20071203230629.725f4c7a@the-village.bc.nu> <6934efce0712040954v74cf0b4bk19b49988bc828233@mail.gmail.com> <20071204203536.2bf6d025@the-village.bc.nu> <6934efce0712041354n47c11d6ckbc7f4aa1e7c85f@mail.gmail.com> <20071204232449.6148e152@the-village.bc.nu> <6934efce0712041608w2e25587n6b2d738fa0265d9d@mail.gmail.com> <20071205002454.52ea755c@the-village.bc.nu> <6934efce0712051401x2b137420hb04f971e1ca2cbf6@mail.gmail.com> X-Google-Sender-Auth: 471eca0eb49e0b6d Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1355 Lines: 40 Hi, On Dec 6, 2007 7:01 AM, Jared Hulbert wrote: > > Probably about 1000 clocks but its always going to depend upon the > > workload and whether any other work can be done usefully. > > Yeah. Sounds right, in the microsecond range. Be interesting to see data. > > Anybody have ideas on what kind of experiments could confirm this > estimate is right? Is it the right place to write synchronously? Now only concern the SATA. Thank you, Kyungmin Park diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c index 3b927be..cce0618 100644 --- a/block/ll_rw_blk.c +++ b/block/ll_rw_blk.c @@ -3221,6 +3221,13 @@ static inline void __generic_make_request(struct bio *bio if (bio_check_eod(bio, nr_sectors)) goto end_io; +#if 1 + /* FIXME simple hack */ + if (MAJOR(bio->bi_bdev->bd_dev) == 8 && bio_data_dir(bio) == WRITE) { + /* WRITE_SYNC */ + bio->bi_rw |= (1 << BIO_RW_SYNC); + } +#endif /* * Resolve the mapping until finished. (drivers are * still free to implement/resolve their own stacking -- 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/