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Tsirkin" , Peter Maydell , qemu-block@nongnu.org, Stefan Hajnoczi , Kevin Wolf References: <20250610123709.835102-1-berrange@redhat.com> <20250610123709.835102-25-berrange@redhat.com> Content-Language: en-US From: Harsh Prateek Bora In-Reply-To: <20250610123709.835102-25-berrange@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Authority-Analysis: v=2.4 cv=Pfr/hjhd c=1 sm=1 tr=0 ts=684947be cx=c_pps a=aDMHemPKRhS1OARIsFnwRA==:117 a=aDMHemPKRhS1OARIsFnwRA==:17 a=IkcTkHD0fZMA:10 a=6IFa9wvqVegA:10 a=f7IdgyKtn90A:10 a=20KFwNOVAAAA:8 a=VnNF1IyMAAAA:8 a=yBPMMN9q8ypsF3GSx8wA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 X-Proofpoint-GUID: WMNgCahv88rqYApPUIT87_guPOSn00DD X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwNjExMDA3NiBTYWx0ZWRfX0gD4oh/Vkx62 JP1WROr2vBAUVa0ZxEgZGz/M20H0VmGouLpHDmuMx1/1NGjl7w4pOyejMnOuBdEO08WXdlQh7zj cHpwwH+P7Umavu5ubOyRk1t5JdHaCYnKxmyknZnVGufw+VGx2LpVAOpQpYOEKml3Dp6LdTgfhMT gDqSKpdDHJM23BdR9GN2vksU+6izYOWP/vLXipFW8D26wBNJOb1/VJZjGjAfv/ek8QTVZmKed/q dnMpYYFcxNd4VPuMgQPV8XJn0Fa9NBHqRRFpvUOl+KzMg32W0QqAWXKGHcZJx4s1tIYtsemZGio CJzonyOaUeVdhb4VZ3EU7gas8/KhFrkI2CK2LdbUg8/2YFg8w2tmZoEqTbfoWenrpKezOF0N/Fu YU5Ty5DABDmM/14eq+Aw1YMfA/Dx9gA+Vct+CD76RK/pIP6y7H17MALHgFw2P2M5X/WZdhgI X-Proofpoint-ORIG-GUID: WMNgCahv88rqYApPUIT87_guPOSn00DD X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1099,Hydra:6.0.736,FMLib:17.12.80.40 definitions=2025-06-11_03,2025-06-10_01,2025-03-28_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 priorityscore=1501 impostorscore=0 suspectscore=0 adultscore=0 clxscore=1011 phishscore=0 bulkscore=0 malwarescore=0 mlxlogscore=821 mlxscore=0 lowpriorityscore=0 classifier=spam authscore=0 authtc=n/a authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2505280000 definitions=main-2506110076 Received-SPF: pass client-ip=148.163.158.5; envelope-from=harshpb@linux.ibm.com; helo=mx0b-001b2d01.pphosted.com X-Spam_score_int: -26 X-Spam_score: -2.7 X-Spam_bar: -- X-Spam_report: (-2.7 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, 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: 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 On 6/10/25 18:07, Daniel P. Berrangé wrote: > The 'occ_model_tick' method has a 12k struct used for copying > data between guest and host. Skip the automatic zero-init of this > struct to eliminate the performance overhead in the I/O hot path. > > The 'dynamic_data' buffer will be fully initialized when reading > data from the guest. > > Signed-off-by: Daniel P. Berrangé > --- > hw/ppc/pnv_occ.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/hw/ppc/pnv_occ.c b/hw/ppc/pnv_occ.c > index fa6f31cb8d..24b789c191 100644 > --- a/hw/ppc/pnv_occ.c > +++ b/hw/ppc/pnv_occ.c > @@ -789,7 +789,7 @@ static bool occ_opal_process_command(PnvOCC *occ, > > static bool occ_model_tick(PnvOCC *occ) > { > - struct occ_dynamic_data dynamic_data; > + QEMU_UNINITIALIZED struct occ_dynamic_data dynamic_data; Reviewed-by: Harsh Prateek Bora > > if (!occ_read_dynamic_data(occ, &dynamic_data, NULL)) { > /* Can't move OCC state field to safe because we can't map it! */