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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Bobby Eshleman CC: , , , , , , From: Arseniy Krasnov Subject: [RFC PATCH v5 2/2] virtio/vsock: check argument to avoid no effect call X-Originating-IP: [172.16.1.6] X-ClientProxiedBy: S-MS-EXCH01.sberdevices.ru (172.16.1.4) To S-MS-EXCH01.sberdevices.ru (172.16.1.4) X-KSMG-Rule-ID: 4 X-KSMG-Message-Action: clean X-KSMG-AntiSpam-Status: not scanned, disabled by settings X-KSMG-AntiSpam-Interceptor-Info: not scanned X-KSMG-AntiPhishing: not scanned, disabled by settings X-KSMG-AntiVirus: Kaspersky Secure Mail Gateway, version 1.1.2.30, bases: 2023/03/22 14:20:00 #20991698 X-KSMG-AntiVirus-Status: Clean, skipped X-Spam-Status: No, score=-0.2 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,DKIM_VALID_EF,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1761095413754409900?= X-GMAIL-MSGID: =?utf-8?q?1761095413754409900?= Both of these functions have no effect when input argument is 0, so to avoid useless spinlock access, check argument before it. Signed-off-by: Arseniy Krasnov Reviewed-by: Stefano Garzarella --- net/vmw_vsock/virtio_transport_common.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c index 9e87c7d4d7cf..312658c176bd 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -302,6 +302,9 @@ u32 virtio_transport_get_credit(struct virtio_vsock_sock *vvs, u32 credit) { u32 ret; + if (!credit) + return 0; + spin_lock_bh(&vvs->tx_lock); ret = vvs->peer_buf_alloc - (vvs->tx_cnt - vvs->peer_fwd_cnt); if (ret > credit) @@ -315,6 +318,9 @@ EXPORT_SYMBOL_GPL(virtio_transport_get_credit); void virtio_transport_put_credit(struct virtio_vsock_sock *vvs, u32 credit) { + if (!credit) + return; + spin_lock_bh(&vvs->tx_lock); vvs->tx_cnt -= credit; spin_unlock_bh(&vvs->tx_lock);