From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 596DDC433EF for ; Fri, 5 Nov 2021 15:15:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3CFC5611CE for ; Fri, 5 Nov 2021 15:15:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233497AbhKEPSQ (ORCPT ); Fri, 5 Nov 2021 11:18:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37634 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233378AbhKEPSP (ORCPT ); Fri, 5 Nov 2021 11:18:15 -0400 Received: from metanate.com (unknown [IPv6:2001:8b0:1628:5005::111]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8DF41C061714; Fri, 5 Nov 2021 08:15:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=metanate.com; s=stronger; h=In-Reply-To:Content-Type:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description; bh=vj1Y8Yv+t+83fnDU9eN1bFfDvaknUqC+W0ZNrx23L/U=; b=m9Pra IbzxNsNJ113UP1/JZWfzDx+yYKJVoAh7ltJ2/bgX2A2gAgCzg0r6hciQFnn6672sHIdl+3ZPPI0V/ SrF5yj/FnTte56oYpbmQ5w2CA/1LprZAoJ/7JIVUwgcSJegSNpJEh2jXWM7dUn+1cTx3Zzm5o38di r8IihhsWigOsJzuPWQT6jg0hSSGOwvsbZ8fp6Fp7cOlVY5t5RK86xK5sl6qAcp/rlct+vaSTIcbpM jR+9oxi5D6VamP+9jReAR9bVWVPxanM6OTNcUTRPxHtfCwyefv9+0l64Tyxtv9j/rSabjjcCx8rGR s3YDT9pafAyxrCof1MaYXZbqouh5w==; Received: from [81.174.171.191] (helo=donbot) by email.metanate.com with esmtpsa (TLS1.3) tls TLS_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1mj0wC-0004zX-Kg; Fri, 05 Nov 2021 15:15:28 +0000 Date: Fri, 5 Nov 2021 15:15:27 +0000 From: John Keeping To: Nathan Chancellor Cc: Minas Harutyunyan , Greg Kroah-Hartman , Nick Desaulniers , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev Subject: Re: [PATCH v2] usb: dwc2: hcd_queue: Fix use of floating point literal Message-ID: References: <20211105145802.2520658-1-nathan@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211105145802.2520658-1-nathan@kernel.org> X-Authenticated: YES Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On Fri, Nov 05, 2021 at 07:58:03AM -0700, Nathan Chancellor wrote: > A new commit in LLVM causes an error on the use of 'long double' when > '-mno-x87' is used, which the kernel does through an alias, > '-mno-80387' (see the LLVM commit below for more details around why it > does this). > > drivers/usb/dwc2/hcd_queue.c:1744:25: error: expression requires 'long double' type support, but target 'x86_64-unknown-linux-gnu' does not support it > delay = ktime_set(0, DWC2_RETRY_WAIT_DELAY); > ^ > drivers/usb/dwc2/hcd_queue.c:62:34: note: expanded from macro 'DWC2_RETRY_WAIT_DELAY' > #define DWC2_RETRY_WAIT_DELAY (1 * 1E6L) > ^ > 1 error generated. > > This happens due to the use of a 'long double' literal. The 'E6' part of > '1E6L' causes the literal to be a 'double' then the 'L' suffix promotes > it to 'long double'. > > There is no visible reason for a floating point value in this driver, as > the value is only used as a parameter to a function that expects an > integer type. Use NSEC_PER_MSEC, which is the same integer value as > '1E6L', to avoid changing functionality but fix the error. > > Fixes: 6ed30a7d8ec2 ("usb: dwc2: host: use hrtimer for NAK retries") > Link: https://github.com/ClangBuiltLinux/linux/issues/1497 > Link: https://github.com/llvm/llvm-project/commit/a8083d42b1c346e21623a1d36d1f0cadd7801d83 > Signed-off-by: Nathan Chancellor > Reviewed-by: Nick Desaulniers Reviewed-by: John Keeping > --- > > v1 -> v2: https://lore.kernel.org/r/20211104215923.719785-1-nathan@kernel.org/ > > * Use NSEC_PER_MSEC instead of USEC_PER_SEC, as the units of the second > parameter of ktime_set is nanoseconds. Thanks to John Keeping for > pointing this out. > > * Pick up Nick's review tag. > > drivers/usb/dwc2/hcd_queue.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/usb/dwc2/hcd_queue.c b/drivers/usb/dwc2/hcd_queue.c > index 89a788326c56..24beff610cf2 100644 > --- a/drivers/usb/dwc2/hcd_queue.c > +++ b/drivers/usb/dwc2/hcd_queue.c > @@ -59,7 +59,7 @@ > #define DWC2_UNRESERVE_DELAY (msecs_to_jiffies(5)) > > /* If we get a NAK, wait this long before retrying */ > -#define DWC2_RETRY_WAIT_DELAY (1 * 1E6L) > +#define DWC2_RETRY_WAIT_DELAY (1 * NSEC_PER_MSEC) > > /** > * dwc2_periodic_channel_available() - Checks that a channel is available for a > > base-commit: d4439a1189f93d0ac1eaf0197db8e6b3e197d5c7 > -- > 2.34.0.rc0 >