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[213.220.210.175]) by smtp.gmail.com with ESMTPSA id g3sm199165wrb.46.2020.06.17.09.48.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 17 Jun 2020 09:48:07 -0700 (PDT) From: "Andrea Parri (Microsoft)" To: "K . Y . Srinivasan" , Haiyang Zhang , Stephen Hemminger , Wei Liu , Michael Kelley Cc: linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, "Andrea Parri (Microsoft)" Subject: [PATCH 8/8] Drivers: hv: vmbus: Remove the lock field from the vmbus_channel struct Date: Wed, 17 Jun 2020 18:46:42 +0200 Message-Id: <20200617164642.37393-9-parri.andrea@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200617164642.37393-1-parri.andrea@gmail.com> References: <20200617164642.37393-1-parri.andrea@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-hyperv-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hyperv@vger.kernel.org The spinlock is (now) *not used to protect test-and-set accesses to attributes of the structure or sc_list operations. There is, AFAICT, a distinct lack of {WRITE,READ}_ONCE()s in the handling of channel->state, but the changes below do not seem to make things "worse". ;-) Signed-off-by: Andrea Parri (Microsoft) --- drivers/hv/channel.c | 6 +----- drivers/hv/channel_mgmt.c | 1 - include/linux/hyperv.h | 6 ------ 3 files changed, 1 insertion(+), 12 deletions(-) diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c index 8848d1548b3f2..3ebda7707e46a 100644 --- a/drivers/hv/channel.c +++ b/drivers/hv/channel.c @@ -129,12 +129,8 @@ static int __vmbus_open(struct vmbus_channel *newchannel, send_pages = newchannel->ringbuffer_send_offset; recv_pages = newchannel->ringbuffer_pagecount - send_pages; - spin_lock_irqsave(&newchannel->lock, flags); - if (newchannel->state != CHANNEL_OPEN_STATE) { - spin_unlock_irqrestore(&newchannel->lock, flags); + if (newchannel->state != CHANNEL_OPEN_STATE) return -EINVAL; - } - spin_unlock_irqrestore(&newchannel->lock, flags); newchannel->state = CHANNEL_OPENING_STATE; newchannel->onchannel_callback = onchannelcallback; diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c index 92f8bb2077a94..591106cf58fc0 100644 --- a/drivers/hv/channel_mgmt.c +++ b/drivers/hv/channel_mgmt.c @@ -317,7 +317,6 @@ static struct vmbus_channel *alloc_channel(void) return NULL; spin_lock_init(&channel->sched_lock); - spin_lock_init(&channel->lock); init_completion(&channel->rescind_event); INIT_LIST_HEAD(&channel->sc_list); diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h index 690394b79d727..38100e80360ac 100644 --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -840,12 +840,6 @@ struct vmbus_channel { */ void (*chn_rescind_callback)(struct vmbus_channel *channel); - /* - * The spinlock to protect the structure. It is being used to protect - * test-and-set access to various attributes of the structure as well - * as all sc_list operations. - */ - spinlock_t lock; /* * All Sub-channels of a primary channel are linked here. */ -- 2.25.1