From patchwork Wed Nov 3 21:16:53 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Christophe JAILLET X-Patchwork-Id: 1550553 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by bilbo.ozlabs.org (Postfix) with ESMTP id 4Hl02f74f3z9sPf for ; Thu, 4 Nov 2021 08:16:58 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230172AbhKCVTd (ORCPT ); Wed, 3 Nov 2021 17:19:33 -0400 Received: from smtp02.smtpout.orange.fr ([80.12.242.124]:64526 "EHLO smtp.smtpout.orange.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230070AbhKCVTd (ORCPT ); Wed, 3 Nov 2021 17:19:33 -0400 Received: from pop-os.home ([86.243.171.122]) by smtp.orange.fr with ESMTPA id iNcsmLYXlBazoiNcsmwyh5; Wed, 03 Nov 2021 22:16:55 +0100 X-ME-Helo: pop-os.home X-ME-Auth: YWZlNiIxYWMyZDliZWIzOTcwYTEyYzlhMmU3ZiQ1M2U2MzfzZDfyZTMxZTBkMTYyNDBjNDJlZmQ3ZQ== X-ME-Date: Wed, 03 Nov 2021 22:16:55 +0100 X-ME-IP: 86.243.171.122 From: Christophe JAILLET To: bhelgaas@google.com Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org, Christophe JAILLET Subject: [PATCH] PCI/P2PDMA: Save a few cycles in 'pci_alloc_p2pmem()' Date: Wed, 3 Nov 2021 22:16:53 +0100 Message-Id: X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Use 'percpu_ref_tryget_live_rcu()' instead of 'percpu_ref_tryget_live()' to save a few cycles when it is known that the rcu lock is already taken/released. Signed-off-by: Christophe JAILLET Reviewed-by: Krzysztof Wilczyński Reviewed-by: Logan Gunthorpe Acked-by: Logan Gunthorpe --- drivers/pci/p2pdma.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c index 8d47cb7218d1..081c391690d4 100644 --- a/drivers/pci/p2pdma.c +++ b/drivers/pci/p2pdma.c @@ -710,7 +710,7 @@ void *pci_alloc_p2pmem(struct pci_dev *pdev, size_t size) if (!ret) goto out; - if (unlikely(!percpu_ref_tryget_live(ref))) { + if (unlikely(!percpu_ref_tryget_live_rcu(ref))) { gen_pool_free(p2pdma->pool, (unsigned long) ret, size); ret = NULL; goto out;