Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752770Ab1FMUgp (ORCPT ); Mon, 13 Jun 2011 16:36:45 -0400 Received: from mail-fx0-f52.google.com ([209.85.161.52]:53419 "EHLO mail-fx0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752193Ab1FMUgn (ORCPT ); Mon, 13 Jun 2011 16:36:43 -0400 X-Greylist: delayed 498 seconds by postgrey-1.27 at vger.kernel.org; Mon, 13 Jun 2011 16:36:43 EDT DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=subject:x-duff:mime-version:content-type:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to:x-mailer; b=I5fKO0FHGK+kqElrvPTxubFJAfcZfa+pTxdPe8XDkFMUP0aXKe2+0vVcwNaNnhuf5f 7/wqmOmiSI04NJaUZba41DNvfP3xiBtelKu5KemcUOa2YLOPMJL+TdKiJR9pL/AkyyDH gjUAdMvBnOAmDOuBZtCahvVnm9a1q8QZUn5JE= Subject: Re: [PATCH] sparc, exec: remove redundant addr_limit assignment X-Duff: Duff Lite, Duff Dry, Duff Dark, Lady Duff, Raspberry Duff, Duff Zero Mime-Version: 1.0 (Apple Message framework v1084) Content-Type: text/plain; charset=us-ascii From: Mathias Krause In-Reply-To: <20110611.160842.2135350880385482648.davem@davemloft.net> Date: Mon, 13 Jun 2011 22:28:20 +0200 Cc: akpm@linux-foundation.org, torvalds@linux-foundation.org, sparclinux@vger.kernel.org, linux-kernel@vger.kernel.org Content-Transfer-Encoding: 7bit Message-Id: <09961391-F83F-4499-A0A3-00AA5C2028CE@googlemail.com> References: <1307642718-22257-1-git-send-email-minipli@googlemail.com> <20110609155630.0f734351.akpm@linux-foundation.org> <1307711453-17412-1-git-send-email-minipli@googlemail.com> <20110611.160842.2135350880385482648.davem@davemloft.net> To: David Miller X-Mailer: Apple Mail (2.1084) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1153 Lines: 32 On 12.06.2011, at 01:08 David Miller wrote: > From: Mathias Krause > Date: Fri, 10 Jun 2011 15:10:53 +0200 > >> The address limit is already set in flush_old_exec() so this >> assignment of USER_DS is redundant. >> >> Signed-off-by: Mathias Krause > ... >> @@ -368,9 +368,6 @@ void flush_thread(void) >> >> /* Clear FPU register state. */ >> t->fpsaved[0] = 0; >> - >> - if (get_thread_current_ds() != ASI_AIUS) >> - set_fs(USER_DS); >> } > > Yeah but now you're doing it unconditionally, the guard is here > because the %asi register write which set_fs() does is extremely > expensive on sparc64 and %99.99999 of the time we can avoid it. As Linus already pointed out, that set_fs() was never called because we already had (and still have) an unconditional set_fs() in the arch independent code. So this patch just removes some dead code. Mathias -- 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/