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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Thorsten Winkler , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Sven Schnelle , Sebastian Ott , Ursula Braun , netdev@vger.kernel.org, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, Aliaksei Makarau , Mahanta Jambigi References: <20250720211110.1962169-1-pasic@linux.ibm.com> <6b09d374-528a-4a6d-a6c6-2be840e8a52b-agordeev@linux.ibm.com> Content-Language: en-US From: Alexandra Winter In-Reply-To: <6b09d374-528a-4a6d-a6c6-2be840e8a52b-agordeev@linux.ibm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwNzIxMDA3MCBTYWx0ZWRfX+kuysjCkc8TG hlNBHlxFXDAuDK+SfkI5wlIJMTfa5jIaC0BW6P/yZY0ZzF+eAcnZXlMC8yEXbL379Vk2/sl8IQW ZNp+ezIPSg/XMpBY1gRUmrFegA45M/93rXjuxfzRDkltNX2zYqt1mkp6XGq0UoXjBk+GZ0EhV1d Jcsm01Xl7azHh1JK2xwS08TeKCt6W9AVE844NV5ama8Ds+/7bQ+FQ74iedpQinHJn66d2xTAQeU AGcR7tMCK/i2BcAvG0vNUYNt4JDWaCFnzS58EkTGETeAG3k6tg5Cpat9Rajo59mH8B2H5VrTWET x2mNlX5fd+CL93f8H6NHDSXqIumvFKw8LWW12ZapIo8/it+1tFQGOhJxjQrFXMo4to4hyflptJK gnnHVegopkEB6wNNS2Sj3lgzXrAto6v3RyOdLHCw1m94Q+Uo8a+XE6BlmM8mDh1kQJgVbZWE X-Proofpoint-GUID: Fr7qEZE_Y6tNPL_DsKWroJAaamlfoA4n X-Proofpoint-ORIG-GUID: IbThzE3dxjrHS0PyoWR5wMWtAnF-ownJ X-Authority-Analysis: v=2.4 cv=X9RSKHTe c=1 sm=1 tr=0 ts=687df7a4 cx=c_pps a=AfN7/Ok6k8XGzOShvHwTGQ==:117 a=AfN7/Ok6k8XGzOShvHwTGQ==:17 a=IkcTkHD0fZMA:10 a=Wb1JkmetP80A:10 a=n0eagUHsWyY7jrG6XxkA:9 a=QEXdDO2ut3YA:10 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1099,Hydra:6.1.9,FMLib:17.12.80.40 definitions=2025-07-21_02,2025-07-21_01,2025-03-28_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 impostorscore=0 priorityscore=1501 adultscore=0 lowpriorityscore=0 phishscore=0 malwarescore=0 clxscore=1011 mlxscore=0 spamscore=0 suspectscore=0 mlxlogscore=658 bulkscore=0 classifier=spam authscore=0 authtc=n/a authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2505280000 definitions=main-2507210070 On 21.07.25 09:30, Alexander Gordeev wrote: > On Sun, Jul 20, 2025 at 11:11:09PM +0200, Halil Pasic wrote: > > Hi Halil, > > ... >> @@ -129,7 +129,9 @@ static int ism_cmd(struct ism_dev *ism, void *cmd) >> { >> struct ism_req_hdr *req = cmd; >> struct ism_resp_hdr *resp = cmd; >> + unsigned long flags; >> >> + spin_lock_irqsave(&ism->cmd_lock, flags); > > I only found smcd_handle_irq() scheduling a tasklet, but no commands issued. > Do we really need disable interrupts? You are right in current code, the interrupt and event handlers of ism and smcd never issue a control command that calls ism_cmd(). OTOH, future ism clients could do that. The control commands are not part of the data path, but of connection establish. So I don't really expect a performance impact. I have it on my ToDo list, to change this to threaded interrupts in the future. So no strong opinion on my side. Simple spin_lock is fine with me. > >> __ism_write_cmd(ism, req + 1, sizeof(*req), req->len - sizeof(*req)); >> __ism_write_cmd(ism, req, 0, sizeof(*req)); >> >> @@ -143,6 +145,7 @@ static int ism_cmd(struct ism_dev *ism, void *cmd) >> } >> __ism_read_cmd(ism, resp + 1, sizeof(*resp), resp->len - sizeof(*resp)); >> out: >> + spin_unlock_irqrestore(&ism->cmd_lock, flags); >> return resp->ret; >> } >> > ... > > Thanks! >