From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.proxmox.com (Postfix) with ESMTPS id 37B72921FA for ; Fri, 6 Oct 2023 12:23:20 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 21CF5325D9 for ; Fri, 6 Oct 2023 12:23:20 +0200 (CEST) Received: from proxmox-new.maurer-it.com (proxmox-new.maurer-it.com [94.136.29.106]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS for ; Fri, 6 Oct 2023 12:23:19 +0200 (CEST) Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id D0AD843572 for ; Fri, 6 Oct 2023 12:23:18 +0200 (CEST) Message-ID: <56d17c5d-f94f-b514-45c7-5fba40e393c2@proxmox.com> Date: Fri, 6 Oct 2023 12:23:14 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.15.1 Content-Language: en-US From: Fiona Ebner To: pve-devel@lists.proxmox.com Reply-To: Proxmox VE development discussion References: <20230928125926.202540-1-f.ebner@proxmox.com> <20230928125926.202540-6-f.ebner@proxmox.com> In-Reply-To: <20230928125926.202540-6-f.ebner@proxmox.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-SPAM-LEVEL: Spam detection results: 0 AWL 2.028 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% DMARC_MISSING 0.1 Missing DMARC policy KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment NICE_REPLY_A -4.219 Looks like a legit reply (A) SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record Subject: Re: [pve-devel] [PATCH qemu 5/7] add patch to disable graph locking X-BeenThere: pve-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE development discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 06 Oct 2023 10:23:20 -0000 Am 28.09.23 um 14:59 schrieb Fiona Ebner: > + void bdrv_graph_wrlock(BlockDriverState *bs) > + { > + AioContext *ctx = NULL; > + > + GLOBAL_STATE_CODE(); > ++ /* > ++ * TODO Some callers hold an AioContext lock when this is called, which > ++ * causes deadlocks. Reenable once the AioContext locking is cleaned up (or > ++ * AioContext locks are gone). > ++ */ > ++#if 0 > + assert(!qatomic_read(&has_writer)); > ++#endif > + > + /* > + * Release only non-mainloop AioContext. The mainloop often relies on the > +@@ -126,6 +137,7 @@ void bdrv_graph_wrlock(BlockDriverState *bs) > + } > + } > + > ++#if 0 > + /* Make sure that constantly arriving new I/O doesn't cause starvation */ > + bdrv_drain_all_begin_nopoll(); > + > +@@ -154,6 +166,7 @@ void bdrv_graph_wrlock(BlockDriverState *bs) > + } while (reader_count() >= 1); > + > + bdrv_drain_all_end(); > ++#endif > + > + if (ctx) { > + aio_context_acquire(bdrv_get_aio_context(bs)); I missed that there was another commit in between, so the #ifdeffery doesn't get rid of the part releasing+acquiring the AioContext lock. Should not be a real issue, but who knows. I'll send a v2 to make it proper (and also want to pick another stable fix).