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charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: microsoft.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: BYAPR21MB1270.namprd21.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: a2f0aa3a-1c7e-471e-8db6-08da32118cc1 X-MS-Exchange-CrossTenant-originalarrivaltime: 09 May 2022 23:13:38.3024 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 72f988bf-86f1-41af-91ab-2d7cd011db47 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: 1g+Rj5cd74MyaJwJJH3VyHQcebjgpzTUwh3jgzKBMLAQ0eUXZH9xJN+FK10KkdTbCjB3QaHG5deYoT0S5QAn6g== X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN2PR21MB1200 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > From: Jeffrey Hugo > Sent: Monday, May 9, 2022 2:48 PM > Subject: [PATCH 1/2] PCI: hv: Reuse existing ITRE allocation in s/ITRE/IRTE. I suppose Wei can help fix this without a v2 :-) > compose_msi_msg() > ... > Currently if compose_msi_msg() is called multiple times, it will free any > previous ITRE allocation, and generate a new allocation. While nothing > prevents this from occurring, it is extranious when Linux could just reus= e s/extranious/extraneous > the existing allocation and avoid a bunch of overhead. >=20 > However, when future ITRE allocations operate on blocks of MSIs instead o= f s/ITRE/IRTE > a single line, freeing the allocation will impact all of the lines. This > could cause an issue where an allocation of N MSIs occurs, then some of > the lines are retargeted, and finally the allocation is freed/reallocated= . > The freeing of the allocation removes all of the configuration for the > entire block, which requires all the lines to be retargeted, which might > not happen since some lines might already be unmasked/active. >=20 > Signed-off-by: Jeffrey Hugo Reviewed-by: Dexuan Cui Tested-by: Dexuan Cui