From owner-dev-commits-src-main@freebsd.org Fri Sep 10 21:27:58 2021 Return-Path: Delivered-To: dev-commits-src-main@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 7CAB0664DDC; Fri, 10 Sep 2021 21:27:58 +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 4H5prG2s2gz4k4X; Fri, 10 Sep 2021 21:27:58 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (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 did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 3AEC614783; Fri, 10 Sep 2021 21:27:58 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 18ALRwOH020666; Fri, 10 Sep 2021 21:27:58 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 18ALRwOV020665; Fri, 10 Sep 2021 21:27:58 GMT (envelope-from git) Date: Fri, 10 Sep 2021 21:27:58 GMT Message-Id: <202109102127.18ALRwOV020665@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Mark Johnston Subject: git: 74a68313b503 - main - socket: Add macros to lock socket buffers using socket references MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: markj X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 74a68313b503940158a2e8e8f02626d7cdbdaff9 Auto-Submitted: auto-generated X-BeenThere: dev-commits-src-main@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Commit messages for the main branch of the src repository List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 10 Sep 2021 21:27:58 -0000 The branch main has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=74a68313b503940158a2e8e8f02626d7cdbdaff9 commit 74a68313b503940158a2e8e8f02626d7cdbdaff9 Author: Mark Johnston AuthorDate: 2021-09-10 21:20:39 +0000 Commit: Mark Johnston CommitDate: 2021-09-10 21:20:39 +0000 socket: Add macros to lock socket buffers using socket references Since commit c67f3b8b78e50c6df7c057d6cf108e4d6b4312d0 the sockbuf mutexes belong to the containing socket. Sockbufs contain a pointer to a mutex, which by default is initialized to the corresponding mutexes in the socket. The SOCKBUF_LOCK() etc. macros operate on this pointer. However, the pointer is clobbered by listen(2) so it's not safe to use them unless one is sure that the socket is not a listening socket. This change introduces a new set of macros which lock socket buffers through the socket. This is a bit cheaper since it removes the pointer indirection, and allows one to safely lock socket buffers and then check for a listening socket. For MFC, these macros should be reimplemented in terms of the existing socket buffer layout. Reviewed by: tuexen, gallatin, jhb Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D31900 --- sys/sys/sockbuf.h | 7 +++++-- sys/sys/socketvar.h | 30 ++++++++++++++++++++++++++++-- 2 files changed, 33 insertions(+), 4 deletions(-) diff --git a/sys/sys/sockbuf.h b/sys/sys/sockbuf.h index 3b345870bd5f..3fc9b10cd240 100644 --- a/sys/sys/sockbuf.h +++ b/sys/sys/sockbuf.h @@ -118,8 +118,11 @@ struct sockbuf { #ifdef _KERNEL /* - * Per-socket buffer mutex used to protect most fields in the socket - * buffer. + * Per-socket buffer mutex used to protect most fields in the socket buffer. + * These make use of the mutex pointer embedded in struct sockbuf, which + * currently just references mutexes in the containing socket. The + * SOCK_SENDBUF_LOCK() etc. macros can be used instead of or in combination with + * these locking macros. */ #define SOCKBUF_MTX(_sb) ((_sb)->sb_mtx) #define SOCKBUF_LOCK_INIT(_sb, _name) \ diff --git a/sys/sys/socketvar.h b/sys/sys/socketvar.h index 69dd1706e366..57913f7bbd65 100644 --- a/sys/sys/socketvar.h +++ b/sys/sys/socketvar.h @@ -77,8 +77,8 @@ enum socket_qstate { * Locking key to struct socket: * (a) constant after allocation, no locking required. * (b) locked by SOCK_LOCK(so). - * (cr) locked by SOCKBUF_LOCK(&so->so_rcv). - * (cs) locked by SOCKBUF_LOCK(&so->so_snd). + * (cr) locked by SOCK_RECVBUF_LOCK(so)/SOCKBUF_LOCK(&so->so_rcv). + * (cs) locked by SOCK_SENDBUF_LOCK(so)/SOCKBUF_LOCK(&so->so_snd). * (e) locked by SOLISTEN_LOCK() of corresponding listening socket. * (f) not locked since integer reads/writes are atomic. * (g) used only as a sleep/wakeup address, no value. @@ -255,6 +255,32 @@ struct socket { ("%s: %p not listening", __func__, (sol))); \ } while (0) +/* + * Socket buffer locks. These manipulate the same mutexes as SOCKBUF_LOCK() + * and related macros. + */ +#define SOCK_RECVBUF_MTX(so) \ + (&(so)->so_rcv_mtx) +#define SOCK_RECVBUF_LOCK(so) \ + mtx_lock(SOCK_RECVBUF_MTX(so)) +#define SOCK_RECVBUF_UNLOCK(so) \ + mtx_unlock(SOCK_RECVBUF_MTX(so)) +#define SOCK_RECVBUF_LOCK_ASSERT(so) \ + mtx_assert(SOCK_RECVBUF_MTX(so), MA_OWNED) +#define SOCK_RECVBUF_UNLOCK_ASSERT(so) \ + mtx_assert(SOCK_RECVBUF_MTX(so), MA_NOTOWNED) + +#define SOCK_SENDBUF_MTX(so) \ + (&(so)->so_snd_mtx) +#define SOCK_SENDBUF_LOCK(so) \ + mtx_lock(SOCK_SENDBUF_MTX(so)) +#define SOCK_SENDBUF_UNLOCK(so) \ + mtx_unlock(SOCK_SENDBUF_MTX(so)) +#define SOCK_SENDBUF_LOCK_ASSERT(so) \ + mtx_assert(SOCK_SENDBUF_MTX(so), MA_OWNED) +#define SOCK_SENDBUF_UNLOCK_ASSERT(so) \ + mtx_assert(SOCK_SENDBUF_MTX(so), MA_NOTOWNED) + /* * Macros for sockets and socket buffering. */