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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 111F8C77B7A for ; Thu, 1 Jun 2023 13:28:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233975AbjFAN2m (ORCPT ); Thu, 1 Jun 2023 09:28:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37262 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233971AbjFAN2W (ORCPT ); Thu, 1 Jun 2023 09:28:22 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DC5E3E6A for ; Thu, 1 Jun 2023 06:28:06 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id AE119644E0 for ; Thu, 1 Jun 2023 13:28:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C7CF1C4339B; Thu, 1 Jun 2023 13:28:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1685626086; bh=Av6Qp9Uh8t3sKnlxPA/NEwE1ChSJ4ZUeAMOBvYH+PfM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kKQuOKi4FlxkTKtIJ5oQgSKaFcPsotWuYB7D9gYTm2AXFIqVFnTX2ATMJ/BqEg/zu qgYCB3i4hlZx/dLwLNocbqGR1fzWE+OzdrHA8jvGWuMY8hEYIcOeE1Ith4hENLvlMU 2ZZcVeb29igoi8Gm0NLTHHVNC+jDscoiSxBRRjd4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yunsheng Lin , Jesper Dangaard Brouer , Ilias Apalodimas , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.1 25/42] page_pool: fix inconsistency for page_pool_ring_[un]lock() Date: Thu, 1 Jun 2023 14:21:34 +0100 Message-Id: <20230601131940.143968395@linuxfoundation.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230601131939.051934720@linuxfoundation.org> References: <20230601131939.051934720@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Yunsheng Lin [ Upstream commit 368d3cb406cdd074d1df2ad9ec06d1bfcb664882 ] page_pool_ring_[un]lock() use in_softirq() to decide which spin lock variant to use, and when they are called in the context with in_softirq() being false, spin_lock_bh() is called in page_pool_ring_lock() while spin_unlock() is called in page_pool_ring_unlock(), because spin_lock_bh() has disabled the softirq in page_pool_ring_lock(), which causes inconsistency for spin lock pair calling. This patch fixes it by returning in_softirq state from page_pool_producer_lock(), and use it to decide which spin lock variant to use in page_pool_producer_unlock(). As pool->ring has both producer and consumer lock, so rename it to page_pool_producer_[un]lock() to reflect the actual usage. Also move them to page_pool.c as they are only used there, and remove the 'inline' as the compiler may have better idea to do inlining or not. Fixes: 7886244736a4 ("net: page_pool: Add bulk support for ptr_ring") Signed-off-by: Yunsheng Lin Acked-by: Jesper Dangaard Brouer Acked-by: Ilias Apalodimas Link: https://lore.kernel.org/r/20230522031714.5089-1-linyunsheng@huawei.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- include/net/page_pool.h | 18 ------------------ net/core/page_pool.c | 28 ++++++++++++++++++++++++++-- 2 files changed, 26 insertions(+), 20 deletions(-) diff --git a/include/net/page_pool.h b/include/net/page_pool.h index 34bf531ffc8d6..ad0bafc877d48 100644 --- a/include/net/page_pool.h +++ b/include/net/page_pool.h @@ -383,22 +383,4 @@ static inline void page_pool_nid_changed(struct page_pool *pool, int new_nid) page_pool_update_nid(pool, new_nid); } -static inline void page_pool_ring_lock(struct page_pool *pool) - __acquires(&pool->ring.producer_lock) -{ - if (in_softirq()) - spin_lock(&pool->ring.producer_lock); - else - spin_lock_bh(&pool->ring.producer_lock); -} - -static inline void page_pool_ring_unlock(struct page_pool *pool) - __releases(&pool->ring.producer_lock) -{ - if (in_softirq()) - spin_unlock(&pool->ring.producer_lock); - else - spin_unlock_bh(&pool->ring.producer_lock); -} - #endif /* _NET_PAGE_POOL_H */ diff --git a/net/core/page_pool.c b/net/core/page_pool.c index 193c187998650..2396c99bedeaa 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -133,6 +133,29 @@ EXPORT_SYMBOL(page_pool_ethtool_stats_get); #define recycle_stat_add(pool, __stat, val) #endif +static bool page_pool_producer_lock(struct page_pool *pool) + __acquires(&pool->ring.producer_lock) +{ + bool in_softirq = in_softirq(); + + if (in_softirq) + spin_lock(&pool->ring.producer_lock); + else + spin_lock_bh(&pool->ring.producer_lock); + + return in_softirq; +} + +static void page_pool_producer_unlock(struct page_pool *pool, + bool in_softirq) + __releases(&pool->ring.producer_lock) +{ + if (in_softirq) + spin_unlock(&pool->ring.producer_lock); + else + spin_unlock_bh(&pool->ring.producer_lock); +} + static int page_pool_init(struct page_pool *pool, const struct page_pool_params *params) { @@ -615,6 +638,7 @@ void page_pool_put_page_bulk(struct page_pool *pool, void **data, int count) { int i, bulk_len = 0; + bool in_softirq; for (i = 0; i < count; i++) { struct page *page = virt_to_head_page(data[i]); @@ -633,7 +657,7 @@ void page_pool_put_page_bulk(struct page_pool *pool, void **data, return; /* Bulk producer into ptr_ring page_pool cache */ - page_pool_ring_lock(pool); + in_softirq = page_pool_producer_lock(pool); for (i = 0; i < bulk_len; i++) { if (__ptr_ring_produce(&pool->ring, data[i])) { /* ring full */ @@ -642,7 +666,7 @@ void page_pool_put_page_bulk(struct page_pool *pool, void **data, } } recycle_stat_add(pool, ring, i); - page_pool_ring_unlock(pool); + page_pool_producer_unlock(pool, in_softirq); /* Hopefully all pages was return into ptr_ring */ if (likely(i == bulk_len)) -- 2.39.2