From nobody Mon Feb 07 19:07:50 2022 X-Original-To: dev-commits-src-main@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id B0E1119BE342; Mon, 7 Feb 2022 19:07:50 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4JswdL4TJFz3GNQ; Mon, 7 Feb 2022 19:07:50 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1644260870; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; 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Mon, 7 Feb 2022 19:07:50 GMT (envelope-from git) Date: Mon, 7 Feb 2022 19:07:50 GMT Message-Id: <202202071907.217J7oNg003285@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Robert Wing Subject: git: c9e023541aef - main - pbuf_ctor(): lock the buffer with LK_NOWAIT List-Id: Commit messages for the main branch of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-main List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-dev-commits-src-main@freebsd.org X-BeenThere: dev-commits-src-main@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: rew X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: c9e023541aefdabf0b602e1fd62f5e21a6f8ffa2 Auto-Submitted: auto-generated ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1644260870; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; 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Instead of blessing ufs and pbufwait, use LK_NOWAIT to prevent recording the lock order. LK_NOWAIT will be a nop here as the lock is dropped in pbuf_dtor(). The takes the same approach as 5875b94c7493 ("buf_alloc(): lock the buffer with LK_NOWAIT"). Reviewed by: kib Differential Revision: https://reviews.freebsd.org/D34183 --- sys/vm/vm_pager.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sys/vm/vm_pager.c b/sys/vm/vm_pager.c index 7dba1c45143d..9b66964b8d8f 100644 --- a/sys/vm/vm_pager.c +++ b/sys/vm/vm_pager.c @@ -467,7 +467,7 @@ pbuf_ctor(void *mem, int size, void *arg, int flags) bp->b_ioflags = 0; bp->b_iodone = NULL; bp->b_error = 0; - BUF_LOCK(bp, LK_EXCLUSIVE, NULL); + BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT, NULL); return (0); }