From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37242) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bw9Uv-0000t0-5C for qemu-devel@nongnu.org; Mon, 17 Oct 2016 11:06:46 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bw9Ur-0005Ot-VR for qemu-devel@nongnu.org; Mon, 17 Oct 2016 11:06:41 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:56518) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1bw9Ur-0005OV-Lx for qemu-devel@nongnu.org; Mon, 17 Oct 2016 11:06:37 -0400 Received: from pps.filterd (m0098399.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id u9HF54eD118689 for ; Mon, 17 Oct 2016 11:06:36 -0400 Received: from e06smtp12.uk.ibm.com (e06smtp12.uk.ibm.com [195.75.94.108]) by mx0a-001b2d01.pphosted.com with ESMTP id 264wef42p8-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Mon, 17 Oct 2016 11:06:36 -0400 Received: from localhost by e06smtp12.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 17 Oct 2016 16:06:33 +0100 Received: from b06cxnps4075.portsmouth.uk.ibm.com (d06relay12.portsmouth.uk.ibm.com [9.149.109.197]) by d06dlp01.portsmouth.uk.ibm.com (Postfix) with ESMTP id 6DA6617D8066 for ; Mon, 17 Oct 2016 16:08:41 +0100 (BST) Received: from d06av07.portsmouth.uk.ibm.com (d06av07.portsmouth.uk.ibm.com [9.149.37.248]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id u9HF6Utn55312564 for ; Mon, 17 Oct 2016 15:06:30 GMT Received: from d06av07.portsmouth.uk.ibm.com (localhost [127.0.0.1]) by d06av07.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id u9HF6Ug1028715 for ; Mon, 17 Oct 2016 11:06:30 -0400 From: Greg Kurz Date: Mon, 17 Oct 2016 17:05:49 +0200 In-Reply-To: <1476716754-26686-1-git-send-email-groug@kaod.org> References: <1476716754-26686-1-git-send-email-groug@kaod.org> Message-Id: <1476716754-26686-8-git-send-email-groug@kaod.org> Subject: [Qemu-devel] [PULL 07/12] 9pfs: only free completed request if not flushed List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Peter Maydell , "Aneesh Kumar K.V" , Greg Kurz If a PDU has a flush request pending, the current code calls pdu_free() twice: 1) pdu_complete()->pdu_free() with pdu->cancelled set, which does nothing 2) v9fs_flush()->pdu_free() with pdu->cancelled cleared, which moves the PDU back to the free list. This works but it complexifies the logic of pdu_free(). With this patch, pdu_complete() only calls pdu_free() if no flush request is pending, i.e. qemu_co_queue_next() returns false. Since pdu_free() is now supposed to be called with pdu->cancelled cleared, the check in pdu_free() is dropped and replaced by an assertion. Signed-off-by: Greg Kurz --- hw/9pfs/9p.c | 18 +++++++----------- 1 file changed, 7 insertions(+), 11 deletions(-) diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c index df8aa726c9a1..f0dc2ce589cd 100644 --- a/hw/9pfs/9p.c +++ b/hw/9pfs/9p.c @@ -627,14 +627,10 @@ V9fsPDU *pdu_alloc(V9fsState *s) void pdu_free(V9fsPDU *pdu) { V9fsState *s = pdu->s; - /* - * Cancelled pdu are added back to the freelist - * by flush request . - */ - if (!pdu->cancelled) { - QLIST_REMOVE(pdu, next); - QLIST_INSERT_HEAD(&s->free_list, pdu, next); - } + + g_assert(!pdu->cancelled); + QLIST_REMOVE(pdu, next); + QLIST_INSERT_HEAD(&s->free_list, pdu, next); } /* @@ -679,9 +675,9 @@ static void coroutine_fn pdu_complete(V9fsPDU *pdu, ssize_t len) pdu_push_and_notify(pdu); /* Now wakeup anybody waiting in flush for this request */ - qemu_co_queue_next(&pdu->complete); - - pdu_free(pdu); + if (!qemu_co_queue_next(&pdu->complete)) { + pdu_free(pdu); + } } static mode_t v9mode_to_mode(uint32_t mode, V9fsString *extension) -- 2.5.5