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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?g7kyQ7Q8MU8BDySZWEzr9EvY05E+PIw78sGSWAJaWVvl8i/mJXL6tvezf5rq?= =?us-ascii?Q?ZIMZ2Ettx7IXIl/8trvC5Y4q2rz5+/VaDC9FCkGPxpKsqcim9OeO5PNzyUsl?= =?us-ascii?Q?nutZRwuyQWH34GMLPtGfP7pWHgo2LqlKqfjGoiKSbNJlwTs5U6piFnLX4quk?= =?us-ascii?Q?zc7XdJEqpJo08ys2lWpoVl6jHZmhNnf6BI7/1q+XXf8UKvHBFf9Y3iofjXu6?= =?us-ascii?Q?6jammOnQYDDH4mx5FhVPg0+RXCKZAkLrvzmyTk87+lVkdKIkTagqxUtHUkSo?= =?us-ascii?Q?/SYqx8i5qHnXXME1Jv0gMlY0eaE7LGPJVtl/utoCJdHWPkDxuPZZPOHUAy5Q?= =?us-ascii?Q?mYYRVf0Jro5OLCu2TK6lHwXwh9yWWrgdE7qztiC7utdGgVtWMgmmpf4PtU6k?= =?us-ascii?Q?qBkKWNYEWsUrHpxugcvnww4TUyLPDKGgXFNgEhc/rAC+IpQHpRNzRzePJlGO?= =?us-ascii?Q?PAqxcM3oJXQ10jiPhdy0tT4r6vqEIycM8wKsT22qLU6SCPLIqzg1UdqkBePn?= =?us-ascii?Q?Vlnzu9KzVvEzRqHZRtH64/ZqLNERE1/yD4y4bAxWNHduLXvBfZFODqJSAENP?= =?us-ascii?Q?+TZOlCF88LeD0I8zWYfCejhAdScVaUYj2lEZxV2gi7GX829GllHaPnXDSBG2?= =?us-ascii?Q?9wPNMdRaBhCOcik0g22Txf3vHLjwfAX3NJE62WMgrRrN2kZHR0RBIj8ST/uO?= =?us-ascii?Q?lRfkYilyKpe9LbfL7eA4rDZkgGAhiF+/WVoOm8vjk4hbnQfwQ9QK2lHTtI3+?= =?us-ascii?Q?kMubW6J5aVCO3U+Wlm5Gqk75gfrS0keX9SqjgPR52yX7oOVrlrbxHG9C1HId?= =?us-ascii?Q?kJMBpLKYLkYRVBrepnxdIDqZOxBCvDuyMv0CRZ0jgyor470XwpkQ/3UZHsTq?= =?us-ascii?Q?pGMoj4f+hORt3Wk6MUdamwxW9Q3hT3l9LxdC7WGxhx/Zekv2TiMRW3ZvAegm?= =?us-ascii?Q?nZtEUDUb2Upvg4jpigv9nVdfR3AOnqz4yh2tWpXkLT276YoDrXVQCeIhL3N0?= =?us-ascii?Q?yPOE5Mtj7GoX7cE1/LlT0+ZoikTiEkvmC5JPKMnKUU6U0pHlLpCjxj6GCCJt?= =?us-ascii?Q?JgkDce4DTlQlEgfAAe5KcrauwH7/nMs6HzaNFXsMflRPP1qL0CFo3/m8iWEP?= =?us-ascii?Q?Y73m8UZG1abY3j0Z7fu5cQSifze0bhcpXUphyzqTnMJ5i0ocNlIn8mvkVB1K?= =?us-ascii?Q?vxye1ke53AMfC5b0xUJBo9vjgTEWwes9e6meF83B2y/JAA9e6JNqE+3JXta1?= =?us-ascii?Q?poRFo+3x2+jyFhT+jA2LrQabi3HsU76KI5QFKr6ncxJHyTCDCfF/qvMcFPOw?= =?us-ascii?Q?WXW2bZmDm7qJWGI4sQPLjAxlH6co9Gr6o3MuRfbvk3FYcxW121W3GdE4E4L/?= =?us-ascii?Q?x12o7JcPUDz4hSHyWbh//TVXKoBuNy0bamkNGkLvx25y9CnMgwcNeSVbxTI9?= =?us-ascii?Q?1Fb1UCujujMgt0rHPfPY5YnIGCTfdVCTMjo/3KG/e73SINbfu2AoEMv5AJ74?= =?us-ascii?Q?0w6//UmPV9hRUbtkjPYy/7GBg/Ys2GybTe9DEH/tkHKdWtKpO9Q+LUfJR2eR?= =?us-ascii?Q?w/kTNDFIPsOkBHyrcTxe4te6JOKRKIXFtNBhoRip0ahAHc/H/NW5fD0KB/dw?= =?us-ascii?Q?/azXgrtW0mJKBLQJIRlCbu0=3D?= X-OriginatorOrg: os.amperecomputing.com X-MS-Exchange-CrossTenant-Network-Message-Id: 93ef8539-d417-43c2-888a-08db6337a70a X-MS-Exchange-CrossTenant-AuthSource: DM5PR0102MB3590.prod.exchangelabs.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 Jun 2023 07:04:48.1202 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3bc2b170-fd94-476d-b0ce-4229bdc904a7 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: fY53U4+BAZDOgitZLoAkIYXXGAY+O/qHIh//7rBki+lzKFOLGv0TAEvpQidvGfWmlMoaqoNxdCHReVnr0cSGyJfCq5/qTBg9h3NeetV5UwWEwOOjhexJTBXmZqMOMupM X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR01MB7581 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Robin, On Thu, 1 Jun 2023, Robin Murphy wrote: > On 2023-06-01 04:01, Ilkka Koskinen wrote: >> Some of the PMUs may share the interrupt. Support them by >> setting IRQF_SHARED > > This has the usual problem of allowing any PMU instance to move the IRQ > affinity to a different CPU without also migrating all the other PMU > contexts, and thus breaking perf core's assumptions of mutual exclusion. I see, I wasn't aware of such an assumption. Sounds like there isn't necessarily an easy and clean solution for the shared interrupt case. I drop the patch and get back on the issue if we come up with something reasonable later. Cheers, Ilkka > > Thanks, > Robin. > >> Signed-off-by: Ilkka Koskinen >> --- >> drivers/perf/arm_cspmu/arm_cspmu.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/perf/arm_cspmu/arm_cspmu.c >> b/drivers/perf/arm_cspmu/arm_cspmu.c >> index 88547a2b73e6..cc5204d1b5fb 100644 >> --- a/drivers/perf/arm_cspmu/arm_cspmu.c >> +++ b/drivers/perf/arm_cspmu/arm_cspmu.c >> @@ -1067,8 +1067,8 @@ static int arm_cspmu_request_irq(struct arm_cspmu >> *cspmu) >> return irq; >> ret = devm_request_irq(dev, irq, arm_cspmu_handle_irq, >> - IRQF_NOBALANCING | IRQF_NO_THREAD, >> dev_name(dev), >> - cspmu); >> + IRQF_NOBALANCING | IRQF_NO_THREAD | >> IRQF_SHARED, >> + dev_name(dev), cspmu); >> if (ret) { >> dev_err(dev, "Could not request IRQ %d\n", irq); >> return ret; >