From patchwork Mon Jul 1 06:20:08 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11025047 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 23CC214F6 for ; Mon, 1 Jul 2019 06:21:53 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2520928329 for ; Mon, 1 Jul 2019 06:21:53 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 1819D284DA; Mon, 1 Jul 2019 06:21:53 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.7 required=2.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B62AC28329 for ; Mon, 1 Jul 2019 06:21:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727365AbfGAGVs (ORCPT ); Mon, 1 Jul 2019 02:21:48 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:48362 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727615AbfGAGUt (ORCPT ); Mon, 1 Jul 2019 02:20:49 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From :Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=bXqDiAvJQco6LqrLgE2xZQsqez3vWo2ZZ+dsCe1H1Ss=; b=MG3bxxRoYFqyzGKH+nrS8kwcHT y4aRjpQDTsEzCm695PnLVWV4y3Nrb7KXmkZHwkZH2ZSo+YGrZHifwDp5/3N2Q85v6ZTpB83rmHwSW 2ZYA10EnLDTDWXHbqkWUJeCn12MZ76qYKsC8+eAoddv6/nO+8gFJtGrc/IScul0oIOi3hf/6zHlwR rA11CIUIt645tmGyq0jk63+C0aXj84m1y56+nvvBKt4o888CTQnsLXmPb0sMZMQWQabg0JYeoJ6lX YpLjzVCN9DpjKikQ+fmNMiIAg0IoiKxuPWZjAs+0qiOKMAUokvMS59FUFc+SETnlDJlxowjQF7kaz 87AtjB8g==; Received: from [46.140.178.35] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92 #3 (Red Hat Linux)) id 1hhpgC-0002z3-Um; Mon, 01 Jul 2019 06:20:45 +0000 From: Christoph Hellwig To: Dan Williams , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , Jason Gunthorpe , Ben Skeggs Cc: Ira Weiny , linux-mm@kvack.org, nouveau@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-nvdimm@lists.01.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Ralph Campbell , John Hubbard , Philip Yang Subject: [PATCH 10/22] mm/hmm: Remove duplicate condition test before wait_event_timeout Date: Mon, 1 Jul 2019 08:20:08 +0200 Message-Id: <20190701062020.19239-11-hch@lst.de> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190701062020.19239-1-hch@lst.de> References: <20190701062020.19239-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Jason Gunthorpe The wait_event_timeout macro already tests the condition as its first action, so there is no reason to open code another version of this, all that does is skip the might_sleep() debugging in common cases, which is not helpful. Further, based on prior patches, we can now simplify the required condition test: - If range is valid memory then so is range->hmm - If hmm_release() has run then range->valid is set to false at the same time as dead, so no reason to check both. - A valid hmm has a valid hmm->mm. Allowing the return value of wait_event_timeout() (along with its internal barriers) to compute the result of the function. Signed-off-by: Jason Gunthorpe Reviewed-by: Ralph Campbell Reviewed-by: John Hubbard Reviewed-by: Ira Weiny Reviewed-by: Christoph Hellwig Tested-by: Philip Yang --- include/linux/hmm.h | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-) diff --git a/include/linux/hmm.h b/include/linux/hmm.h index 1d97b6d62c5b..26e7c477490c 100644 --- a/include/linux/hmm.h +++ b/include/linux/hmm.h @@ -209,17 +209,8 @@ static inline unsigned long hmm_range_page_size(const struct hmm_range *range) static inline bool hmm_range_wait_until_valid(struct hmm_range *range, unsigned long timeout) { - /* Check if mm is dead ? */ - if (range->hmm == NULL || range->hmm->dead || range->hmm->mm == NULL) { - range->valid = false; - return false; - } - if (range->valid) - return true; - wait_event_timeout(range->hmm->wq, range->valid || range->hmm->dead, - msecs_to_jiffies(timeout)); - /* Return current valid status just in case we get lucky */ - return range->valid; + return wait_event_timeout(range->hmm->wq, range->valid, + msecs_to_jiffies(timeout)) != 0; } /*