From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists1p.gnu.org (lists1p.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E61B7C55175 for ; Mon, 3 Aug 2026 08:13:25 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1wqnmP-0001cf-AB; Mon, 03 Aug 2026 04:12:13 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wqnmN-0001bn-0L for qemu-devel@nongnu.org; Mon, 03 Aug 2026 04:12:11 -0400 Received: from mail-wm1-x331.google.com ([2a00:1450:4864:20::331]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1wqnmI-0003ev-OU for qemu-devel@nongnu.org; Mon, 03 Aug 2026 04:12:09 -0400 Received: by mail-wm1-x331.google.com with SMTP id 5b1f17b1804b1-4954df200ddso11280185e9.0 for ; Mon, 03 Aug 2026 01:12:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mihalicyn.com; s=mihalicyn; t=1785744725; x=1786349525; darn=nongnu.org; h=content-transfer-encoding:content-type:mime-version:references :in-reply-to:message-id:date:subject:cc:to:from:from:to:cc:subject :date:message-id:reply-to:content-type; bh=+OQnGd/VssRY3c9PIQDh3w6TM7Z+wYhgLftlLZUUP+k=; b=OYOl1sS9rKSU9HCrLzBCJmdzzjYjm0diNZntQlLK29uQkeCKTihk68K8mp3Tb5ZewQ 8RriBHPlwt8VDjLpaE0PVc+/3TbsQWuNFz3ygFx9NlfKRszbi5/oHhyIpCJRagdqrPSj ECTI3Sgkv5ft/0M1BSiazD10cBHUnerorRN84= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1785744725; x=1786349525; h=content-transfer-encoding:content-type:mime-version:references :in-reply-to:message-id:date:subject:cc:to:from:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=+OQnGd/VssRY3c9PIQDh3w6TM7Z+wYhgLftlLZUUP+k=; b=bGwWFQ1xPSZ9LnaPwbBwvJBUghK1TDZSoG3wGtdKPBNGOIc5xD4fehrja8E06qlK2j CVm6CKkERYeAW7e8QDNh9k9DentLrePx1hgM1kzvgpxFBZAjyQYpXQMJBWzJM0bgBobe o8WKMvj8+AvI8D+anNHDNApvtusYEf7B3TQ1NWEFemCL6XVDA0hpjO3z/VK1mP94eIEd AWHJMEAWUq1AtQ1MKcAKk0YCp+UJHqpgSnOhUYeR8OZyaH3ER7kwIyo+rVcPOKwY3rVW ZryX9RjuMJfVSoz44AWJJ0pWB7hMCDJVP1EHHwH8p4ULbgDOGS/RVZi+O8tcyJiQYvq1 oenA== X-Gm-Message-State: AOJu0YzKf8DkJhnmJO6pijcTGBwtl4HctjbQt8k8r9RH0fK2xIGim4He CNPeiJHb3slroPpqyOtGPeYa5xbuAWeArPqpospPB2X6gUtfSTd+XI9uvEhRfd5RDTKkZiRictv MzLGM X-Gm-Gg: AR+sD10+sHYr6tkhGwH+FE948KVaNSo+qaSG7DmpvuVCwpTubf1u8SIXFQJ44VWBZ8S NWrh1OY0fry3t5LAVc0I+eNxT8YyM9FSl5W9p756nyZqQqTp4ocekjl1lH2y6T7vVgbOIgfYOCT q6d1MigI8BACZGyM9falto1jn61MZWItTJMg9NlmCNkK+wOQqfixgHy6AklcEjf464F5kixDZ/z riS/m0mxM8PogieraN4PEg4huFFySrpm4aF03F37OKYJFxoEMW79MqombGe0zEkKvBgJRkFQtD5 cql8UX4yioWqp6duDC8eaxrUSOUYUzWZywyByzjOa3WAUgZDhmjWkOofdzFI49CSP5oQJHKqzhk +IlEVsWwCD9aaJowy6NmgPk5KGB6oqGmziWjkRKZB2rtIH4F8BVNhow/YqCffbgqgouB5HoY/S1 72GFQvAXEUEwdeBJeP8uyxAGL+quwyI58JF6UpzsIUbGX0rs/2GqYtJMldKcorfNLYL9gE2f4AF bud/fkWOAYLbtTO9ZrcUjAqr3aViITddFD0x6tb42sG37nIvCpo30OigQt6 X-Received: by 2002:a05:600c:1992:b0:498:28b:1045 with SMTP id 5b1f17b1804b1-4980c645611mr150808685e9.3.1785744724777; Mon, 03 Aug 2026 01:12:04 -0700 (PDT) Received: from alex-laptop.lan (p200300cf574a7200803110ea947f174a.dip0.t-ipconnect.de. [2003:cf:574a:7200:8031:10ea:947f:174a]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-49807b98284sm209358435e9.12.2026.08.03.01.12.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 03 Aug 2026 01:12:04 -0700 (PDT) From: Alexander Mikhalitsyn To: qemu-devel@nongnu.org Cc: Manos Pitsidianakis , =?UTF-8?q?Volker=20R=C3=BCmelin?= , =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , Gerd Hoffmann , =?UTF-8?q?Daniel=20P=20=2E=20Berrang=C3=A9?= , Alexander Mikhalitsyn , "Michael S. Tsirkin" , =?UTF-8?q?St=C3=A9phane=20Graber?= , Alexander Mikhalitsyn Subject: [PATCH v5 03/10] hw/audio/virtio-sound: remove command and stream mutexes Date: Mon, 3 Aug 2026 10:11:52 +0200 Message-ID: <20260803081159.91981-4-alexander@mihalicyn.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260803081159.91981-1-alexander@mihalicyn.com> References: <20260803081159.91981-1-alexander@mihalicyn.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=2a00:1450:4864:20::331; envelope-from=alexander@mihalicyn.com; helo=mail-wm1-x331.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Volker Rümelin All code in virtio-snd.c runs with the BQL held. Remove the command queue mutex and the stream queue mutexes. The qatomic functions are also not needed. Signed-off-by: Volker Rümelin [AM: there were too many conflicts, I did `git checkout --ours -- <.>` and then reimplemented the patch idea /AM] Signed-off-by: Alexander Mikhalitsyn Reviewed-by: Marc-André Lureau Reviewed-by: Manos Pitsidianakis --- hw/audio/virtio-snd.c | 246 +++++++++++++++------------------- include/hw/audio/virtio-snd.h | 3 - 2 files changed, 110 insertions(+), 139 deletions(-) diff --git a/hw/audio/virtio-snd.c b/hw/audio/virtio-snd.c index 46d81cc9ec4..cbf739f8a7d 100644 --- a/hw/audio/virtio-snd.c +++ b/hw/audio/virtio-snd.c @@ -19,7 +19,6 @@ #include "qemu/iov.h" #include "qemu/log.h" #include "qemu/error-report.h" -#include "qemu/lockable.h" #include "system/runstate.h" #include "trace.h" #include "qapi/error.h" @@ -442,7 +441,6 @@ static uint32_t virtio_snd_pcm_prepare(VirtIOSound *s, uint32_t stream_id) stream->id = stream_id; stream->s = s; stream->latency_bytes = 0; - qemu_mutex_init(&stream->queue_mutex); QSIMPLEQ_INIT(&stream->queue); /* @@ -566,9 +564,7 @@ static void virtio_snd_handle_pcm_start_stop(VirtIOSound *s, stream = virtio_snd_pcm_get_stream(s, stream_id); if (stream) { - WITH_QEMU_LOCK_GUARD(&stream->queue_mutex) { - stream->active = start; - } + stream->active = start; if (stream->info.direction == VIRTIO_SND_D_OUTPUT) { audio_be_set_active_out(s->audio_be, stream->voice.out, start); } else { @@ -592,10 +588,8 @@ static size_t virtio_snd_pcm_get_io_msgs_count(VirtIOSoundPCMStream *stream) VirtIOSoundPCMBuffer *buffer, *next; size_t count = 0; - WITH_QEMU_LOCK_GUARD(&stream->queue_mutex) { - QSIMPLEQ_FOREACH_SAFE(buffer, &stream->queue, entry, next) { - count += 1; - } + QSIMPLEQ_FOREACH_SAFE(buffer, &stream->queue, entry, next) { + count += 1; } return count; } @@ -737,23 +731,15 @@ static void virtio_snd_process_cmdq(VirtIOSound *s) { virtio_snd_ctrl_command *cmd; - if (unlikely(qatomic_read(&s->processing_cmdq))) { - return; - } - - WITH_QEMU_LOCK_GUARD(&s->cmdq_mutex) { - qatomic_set(&s->processing_cmdq, true); - while (!QTAILQ_EMPTY(&s->cmdq)) { - cmd = QTAILQ_FIRST(&s->cmdq); + while (!QTAILQ_EMPTY(&s->cmdq)) { + cmd = QTAILQ_FIRST(&s->cmdq); - /* process command */ - process_cmd(s, cmd); + /* process command */ + process_cmd(s, cmd); - QTAILQ_REMOVE(&s->cmdq, cmd, next); + QTAILQ_REMOVE(&s->cmdq, cmd, next); - virtio_snd_ctrl_cmd_free(cmd); - } - qatomic_set(&s->processing_cmdq, false); + virtio_snd_ctrl_cmd_free(cmd); } } @@ -896,17 +882,16 @@ static void virtio_snd_handle_tx_xfer(VirtIODevice *vdev, VirtQueue *vq) if (!g_size_checked_add(&tmp, sizeof(VirtIOSoundPCMBuffer), size)) { goto tx_err; } - WITH_QEMU_LOCK_GUARD(&stream->queue_mutex) { - buffer = g_malloc0(sizeof(VirtIOSoundPCMBuffer) + size); - buffer->elem = elem; - buffer->populated = false; - buffer->vq = vq; - buffer->size = size; - buffer->offset = 0; - stream->latency_bytes += size; - - QSIMPLEQ_INSERT_TAIL(&stream->queue, buffer, entry); - } + + buffer = g_malloc0(sizeof(VirtIOSoundPCMBuffer) + size); + buffer->elem = elem; + buffer->populated = false; + buffer->vq = vq; + buffer->size = size; + buffer->offset = 0; + stream->latency_bytes += size; + + QSIMPLEQ_INSERT_TAIL(&stream->queue, buffer, entry); continue; tx_err: @@ -983,14 +968,14 @@ static void virtio_snd_handle_rx_xfer(VirtIODevice *vdev, VirtQueue *vq) if (!g_size_checked_add(&tmp, sizeof(VirtIOSoundPCMBuffer), size)) { goto rx_err; } - WITH_QEMU_LOCK_GUARD(&stream->queue_mutex) { - buffer = g_malloc0(sizeof(VirtIOSoundPCMBuffer) + size); - buffer->elem = elem; - buffer->vq = vq; - buffer->size = 0; - buffer->offset = 0; - QSIMPLEQ_INSERT_TAIL(&stream->queue, buffer, entry); - } + + buffer = g_malloc0(sizeof(VirtIOSoundPCMBuffer) + size); + buffer->elem = elem; + buffer->vq = vq; + buffer->size = 0; + buffer->offset = 0; + QSIMPLEQ_INSERT_TAIL(&stream->queue, buffer, entry); + continue; rx_err: @@ -1094,7 +1079,6 @@ static void virtio_snd_realize(DeviceState *dev, Error **errp) virtio_add_queue(vdev, 64, virtio_snd_handle_tx_xfer); vsnd->queues[VIRTIO_SND_VQ_RX] = virtio_add_queue(vdev, 64, virtio_snd_handle_rx_xfer); - qemu_mutex_init(&vsnd->cmdq_mutex); QTAILQ_INIT(&vsnd->cmdq); QSIMPLEQ_INIT(&vsnd->invalid); @@ -1162,52 +1146,50 @@ static void virtio_snd_pcm_out_cb(void *data, int available) VirtIOSoundPCMBuffer *buffer; size_t size; - WITH_QEMU_LOCK_GUARD(&stream->queue_mutex) { - while (!QSIMPLEQ_EMPTY(&stream->queue)) { - buffer = QSIMPLEQ_FIRST(&stream->queue); - if (!virtio_queue_ready(buffer->vq)) { - return; + while (!QSIMPLEQ_EMPTY(&stream->queue)) { + buffer = QSIMPLEQ_FIRST(&stream->queue); + if (!virtio_queue_ready(buffer->vq)) { + return; + } + if (!stream->active) { + /* Stream has stopped, so do not perform audio_be_write. */ + return_tx_buffer(stream, buffer); + continue; + } + if (!buffer->populated) { + iov_to_buf(buffer->elem->out_sg, + buffer->elem->out_num, + sizeof(virtio_snd_pcm_xfer), + buffer->data, + buffer->size); + buffer->populated = true; + } + for (;;) { + size = audio_be_write(stream->s->audio_be, + stream->voice.out, + buffer->data + buffer->offset, + MIN(buffer->size, available)); + assert(size <= MIN(buffer->size, available)); + if (size == 0) { + /* break out of both loops */ + available = 0; + break; } - if (!stream->active) { - /* Stream has stopped, so do not perform audio_be_write. */ + buffer->size -= size; + buffer->offset += size; + available -= size; + update_latency(stream, size); + if (buffer->size < 1) { return_tx_buffer(stream, buffer); - continue; - } - if (!buffer->populated) { - iov_to_buf(buffer->elem->out_sg, - buffer->elem->out_num, - sizeof(virtio_snd_pcm_xfer), - buffer->data, - buffer->size); - buffer->populated = true; - } - for (;;) { - size = audio_be_write(stream->s->audio_be, - stream->voice.out, - buffer->data + buffer->offset, - MIN(buffer->size, available)); - assert(size <= MIN(buffer->size, available)); - if (size == 0) { - /* break out of both loops */ - available = 0; - break; - } - buffer->size -= size; - buffer->offset += size; - available -= size; - update_latency(stream, size); - if (buffer->size < 1) { - return_tx_buffer(stream, buffer); - break; - } - if (!available) { - break; - } + break; } if (!available) { break; } } + if (!available) { + break; + } } } @@ -1258,55 +1240,53 @@ static void virtio_snd_pcm_in_cb(void *data, int available) VirtIOSoundPCMBuffer *buffer; size_t size, max_size, to_read; - WITH_QEMU_LOCK_GUARD(&stream->queue_mutex) { - while (!QSIMPLEQ_EMPTY(&stream->queue)) { - buffer = QSIMPLEQ_FIRST(&stream->queue); - if (!virtio_queue_ready(buffer->vq)) { - return; - } - if (!stream->active) { - /* Stream has stopped, so do not perform audio_be_read. */ - return_rx_buffer(stream, buffer); - continue; - } + while (!QSIMPLEQ_EMPTY(&stream->queue)) { + buffer = QSIMPLEQ_FIRST(&stream->queue); + if (!virtio_queue_ready(buffer->vq)) { + return; + } + if (!stream->active) { + /* Stream has stopped, so do not perform audio_be_read. */ + return_rx_buffer(stream, buffer); + continue; + } - max_size = iov_size(buffer->elem->in_sg, buffer->elem->in_num); - if (max_size <= sizeof(virtio_snd_pcm_status)) { + max_size = iov_size(buffer->elem->in_sg, buffer->elem->in_num); + if (max_size <= sizeof(virtio_snd_pcm_status)) { + return_rx_buffer(stream, buffer); + continue; + } + max_size -= sizeof(virtio_snd_pcm_status); + + for (;;) { + if (buffer->size >= max_size) { return_rx_buffer(stream, buffer); - continue; + break; } - max_size -= sizeof(virtio_snd_pcm_status); - - for (;;) { - if (buffer->size >= max_size) { - return_rx_buffer(stream, buffer); - break; - } - to_read = stream->params.period_bytes - buffer->size; - to_read = MIN(to_read, available); - to_read = MIN(to_read, max_size - buffer->size); - size = audio_be_read(stream->s->audio_be, - stream->voice.in, - buffer->data + buffer->size, - to_read); - if (!size) { - available = 0; - break; - } - buffer->size += size; - available -= size; - if (buffer->size >= stream->params.period_bytes) { - return_rx_buffer(stream, buffer); - break; - } - if (!available) { - break; - } + to_read = stream->params.period_bytes - buffer->size; + to_read = MIN(to_read, available); + to_read = MIN(to_read, max_size - buffer->size); + size = audio_be_read(stream->s->audio_be, + stream->voice.in, + buffer->data + buffer->size, + to_read); + if (!size) { + available = 0; + break; + } + buffer->size += size; + available -= size; + if (buffer->size >= stream->params.period_bytes) { + return_rx_buffer(stream, buffer); + break; } if (!available) { break; } } + if (!available) { + break; + } } } @@ -1323,11 +1303,9 @@ static inline void virtio_snd_pcm_flush(VirtIOSoundPCMStream *stream) (stream->info.direction == VIRTIO_SND_D_OUTPUT) ? return_tx_buffer : return_rx_buffer; - WITH_QEMU_LOCK_GUARD(&stream->queue_mutex) { - while (!QSIMPLEQ_EMPTY(&stream->queue)) { - buffer = QSIMPLEQ_FIRST(&stream->queue); - cb(stream, buffer); - } + while (!QSIMPLEQ_EMPTY(&stream->queue)) { + buffer = QSIMPLEQ_FIRST(&stream->queue); + cb(stream, buffer); } } @@ -1346,14 +1324,12 @@ static void virtio_snd_unrealize(DeviceState *dev) if (stream) { virtio_snd_process_cmdq(stream->s); virtio_snd_pcm_close(stream); - qemu_mutex_destroy(&stream->queue_mutex); g_free(stream); } } g_free(vsnd->pcm.streams); } g_free(vsnd->pcm.pcm_params); - qemu_mutex_destroy(&vsnd->cmdq_mutex); virtio_delete_queue(vsnd->queues[VIRTIO_SND_VQ_CONTROL]); virtio_delete_queue(vsnd->queues[VIRTIO_SND_VQ_EVENT]); virtio_delete_queue(vsnd->queues[VIRTIO_SND_VQ_TX]); @@ -1374,12 +1350,10 @@ static void virtio_snd_reset(VirtIODevice *vdev) */ g_assert(QSIMPLEQ_EMPTY(&vsnd->invalid)); - WITH_QEMU_LOCK_GUARD(&vsnd->cmdq_mutex) { - while (!QTAILQ_EMPTY(&vsnd->cmdq)) { - cmd = QTAILQ_FIRST(&vsnd->cmdq); - QTAILQ_REMOVE(&vsnd->cmdq, cmd, next); - virtio_snd_ctrl_cmd_free(cmd); - } + while (!QTAILQ_EMPTY(&vsnd->cmdq)) { + cmd = QTAILQ_FIRST(&vsnd->cmdq); + QTAILQ_REMOVE(&vsnd->cmdq, cmd, next); + virtio_snd_ctrl_cmd_free(cmd); } } diff --git a/include/hw/audio/virtio-snd.h b/include/hw/audio/virtio-snd.h index b60b098ccd8..884c475ffd9 100644 --- a/include/hw/audio/virtio-snd.h +++ b/include/hw/audio/virtio-snd.h @@ -143,7 +143,6 @@ struct VirtIOSoundPCMStream { SWVoiceIn *in; SWVoiceOut *out; } voice; - QemuMutex queue_mutex; bool active; uint32_t latency_bytes; QSIMPLEQ_HEAD(, VirtIOSoundPCMBuffer) queue; @@ -215,9 +214,7 @@ struct VirtIOSound { AudioBackend *audio_be; VMChangeStateEntry *vmstate; virtio_snd_config snd_conf; - QemuMutex cmdq_mutex; QTAILQ_HEAD(, virtio_snd_ctrl_command) cmdq; - bool processing_cmdq; /* * Convenience queue to keep track of invalid tx/rx queue messages inside * the tx/rx callbacks. -- 2.47.3