From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38147) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XlGBw-0006dA-W4 for qemu-devel@nongnu.org; Mon, 03 Nov 2014 06:53:07 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XlGBq-0000tF-SF for qemu-devel@nongnu.org; Mon, 03 Nov 2014 06:53:00 -0500 Received: from mx1.redhat.com ([209.132.183.28]:44751) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XlGBq-0000t6-LG for qemu-devel@nongnu.org; Mon, 03 Nov 2014 06:52:54 -0500 From: Stefan Hajnoczi Date: Mon, 3 Nov 2014 11:50:49 +0000 Message-Id: <1415015456-25086-47-git-send-email-stefanha@redhat.com> In-Reply-To: <1415015456-25086-1-git-send-email-stefanha@redhat.com> References: <1415015456-25086-1-git-send-email-stefanha@redhat.com> Subject: [Qemu-devel] [PULL 46/53] blockdev: add note that block_job_cb() must be thread-safe List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Peter Maydell , Stefan Hajnoczi This function is correct but we should document the constraint that everything must be thread-safe. Emitting QMP events and scheduling BHs are both thread-safe so nothing needs to be done here. Signed-off-by: Stefan Hajnoczi Reviewed-by: Max Reitz Message-id: 1413889440-32577-5-git-send-email-stefanha@redhat.com --- blockdev.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/blockdev.c b/blockdev.c index 741df98..774051b 100644 --- a/blockdev.c +++ b/blockdev.c @@ -1929,6 +1929,11 @@ out: static void block_job_cb(void *opaque, int ret) { + /* Note that this function may be executed from another AioContext besides + * the QEMU main loop. If you need to access anything that assumes the + * QEMU global mutex, use a BH or introduce a mutex. + */ + BlockDriverState *bs = opaque; const char *msg = NULL; -- 1.9.3