From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:47244) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fR8Uu-0003vn-6i for qemu-devel@nongnu.org; Thu, 07 Jun 2018 23:55:33 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fR8Ut-0006xa-6e for qemu-devel@nongnu.org; Thu, 07 Jun 2018 23:55:32 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:55844 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fR8Ut-0006xL-0n for qemu-devel@nongnu.org; Thu, 07 Jun 2018 23:55:31 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8438240711D2 for ; Fri, 8 Jun 2018 03:55:30 +0000 (UTC) From: Peter Xu Date: Fri, 8 Jun 2018 11:55:06 +0800 Message-Id: <20180608035511.7439-3-peterx@redhat.com> In-Reply-To: <20180608035511.7439-1-peterx@redhat.com> References: <20180608035511.7439-1-peterx@redhat.com> Subject: [Qemu-devel] [PATCH v10 2/7] monitor: protect mon->fds with mon_lock List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Eric Blake , =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , Markus Armbruster , Stefan Hajnoczi , "Dr . David Alan Gilbert" , peterx@redhat.com mon->fds were protected by BQL. Now protect it by mon_lock so that it can even be used in monitor iothread. Reviewed-by: Stefan Hajnoczi Reviewed-by: Markus Armbruster Signed-off-by: Peter Xu --- monitor.c | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-) diff --git a/monitor.c b/monitor.c index 5bc9b2dcd0..0fba3ccc20 100644 --- a/monitor.c +++ b/monitor.c @@ -212,7 +212,6 @@ struct Monitor { BlockCompletionFunc *password_completion_cb; void *password_opaque; mon_cmd_t *cmd_table; - QLIST_HEAD(,mon_fd_t) fds; QTAILQ_ENTRY(Monitor) entry; /* @@ -224,6 +223,7 @@ struct Monitor { /* * Fields that are protected by the per-monitor lock. */ + QLIST_HEAD(, mon_fd_t) fds; QString *outbuf; guint out_watch; /* Read under either BQL or mon_lock, written with BQL+mon_lock. */ @@ -2187,7 +2187,7 @@ static void hmp_acl_remove(Monitor *mon, const QDict *qdict) void qmp_getfd(const char *fdname, Error **errp) { mon_fd_t *monfd; - int fd; + int fd, tmp_fd; fd = qemu_chr_fe_get_msgfd(&cur_mon->chr); if (fd == -1) { @@ -2202,13 +2202,17 @@ void qmp_getfd(const char *fdname, Error **errp) return; } + qemu_mutex_lock(&cur_mon->mon_lock); QLIST_FOREACH(monfd, &cur_mon->fds, next) { if (strcmp(monfd->name, fdname) != 0) { continue; } - close(monfd->fd); + tmp_fd = monfd->fd; monfd->fd = fd; + qemu_mutex_unlock(&cur_mon->mon_lock); + /* Make sure close() is out of critical section */ + close(tmp_fd); return; } @@ -2217,24 +2221,31 @@ void qmp_getfd(const char *fdname, Error **errp) monfd->fd = fd; QLIST_INSERT_HEAD(&cur_mon->fds, monfd, next); + qemu_mutex_unlock(&cur_mon->mon_lock); } void qmp_closefd(const char *fdname, Error **errp) { mon_fd_t *monfd; + int tmp_fd; + qemu_mutex_lock(&cur_mon->mon_lock); QLIST_FOREACH(monfd, &cur_mon->fds, next) { if (strcmp(monfd->name, fdname) != 0) { continue; } QLIST_REMOVE(monfd, next); - close(monfd->fd); + tmp_fd = monfd->fd; g_free(monfd->name); g_free(monfd); + qemu_mutex_unlock(&cur_mon->mon_lock); + /* Make sure close() is out of critical section */ + close(tmp_fd); return; } + qemu_mutex_unlock(&cur_mon->mon_lock); error_setg(errp, QERR_FD_NOT_FOUND, fdname); } @@ -2242,6 +2253,7 @@ int monitor_get_fd(Monitor *mon, const char *fdname, Error **errp) { mon_fd_t *monfd; + qemu_mutex_lock(&mon->mon_lock); QLIST_FOREACH(monfd, &mon->fds, next) { int fd; @@ -2255,10 +2267,12 @@ int monitor_get_fd(Monitor *mon, const char *fdname, Error **errp) QLIST_REMOVE(monfd, next); g_free(monfd->name); g_free(monfd); + qemu_mutex_unlock(&mon->mon_lock); return fd; } + qemu_mutex_unlock(&mon->mon_lock); error_setg(errp, "File descriptor named '%s' has not been found", fdname); return -1; } -- 2.17.1