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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Z5JkBkxJqdJKR8HQMe3t/AAjAD8B4TYoBiYemTjyvJI9C/T44Oi/Z9PKOGbc?= =?us-ascii?Q?MGxpmm3xUciRSzPKySLkrdE4PPGt/WOdIcXQKnJRnw+u7mFFVoxJ338nkVAD?= =?us-ascii?Q?Twf6icKyxs98fesTbVOWZ/SLkc77cLD4n8l8J1qa3n+2MXX6Q6U9ZdPDOoc0?= =?us-ascii?Q?oH2wVbfbyVCB+ElOZf1Y71/aD5xSQMpDjDCYhUOPPqPGXQngWRRPMC+JQ5Jn?= =?us-ascii?Q?/X72HyR50x2Gcpswv7IUoRWoc3f3aUOBVDf5eOTK0jEegQiSQghQ6g4bb1Gb?= =?us-ascii?Q?1+t6I41lRibZ02OGj5uzytnzgDEVga3RuJ5hdIPUt3gECuQspWkbnG3x79tx?= =?us-ascii?Q?ZkMlXWIjNwZSYJnp80Kj2LlWcwbagoHwbYt1TNVgInuNtbEbKnKzwh+Lnv8N?= =?us-ascii?Q?BXLN2kbuyHxH6R7v+1U+PDfukymXI5OBB/7vz+rSM4YDJuU6WvcvNtj5w1MJ?= =?us-ascii?Q?OsX+d4Sd2B1hJTnLtqhuLOMyrCmkFj2UuHqnZg99TfZzIimmOUBjav8M8pDo?= =?us-ascii?Q?zCdOrJdRAWjv7oinEp/Wzi6zYzBnahxxS4ejbvTgyVsc94LlVjPsZk5jJ5LX?= =?us-ascii?Q?FV6eRJu2Jw2Y0++s/loxIJJylk8LtD/DDJ36l3zJLfqLL/x3wHB4CAtlb9w6?= =?us-ascii?Q?e8UkTYyfk63rc1KsSUY64aPcUVRb5UX21cuyoXVQWQ9o27Zr/lsSfF2U5z0C?= =?us-ascii?Q?xh4Wi8xLSIuMNVI1YS7hVWT9byAv6Jb3AFGM1HtvWSAxMcMkRC7oqHpD2Ifr?= =?us-ascii?Q?j2sxKQT8LvTqgWJLOCQ4I75qrasUEcP7FfXEA8V5Y/71+3hUXzkf5roB6MCH?= =?us-ascii?Q?uVxwxjfymEbDaiHm0u4RWgYjB0VNNerO88/bY1UIfu2AiMVKMRiSeIkyq24N?= =?us-ascii?Q?Wwb43IserZUnr1ljGSFuyalSh8nHyHFVnYagSJ+yJ8+poNXCTTGUEnnh93TC?= =?us-ascii?Q?jrhowoZSEkdk3SoU7Hy+4OMM+vLY5rDomrkLVDnRO41uO90I39g+ORAiSRmr?= =?us-ascii?Q?/meYjFA5rWXajwh00QZ8kRogu6XgJ40pKXl3QpzTEmLw6VfE3exNqMdmXwV0?= =?us-ascii?Q?ZuuqZY3qnrS2tP1UnfelVY+ovkRN/n6genRsGhMEODpfQ6hND925qdD1hB+9?= =?us-ascii?Q?4hUqSHe1ZKSjOXkoDkNd1pdmDZIKWjXwBTHW+6xhf6HUMzCUZid7L65D+5f+?= =?us-ascii?Q?e5RcL2+gQyAj3OGOC49wS9tsJDAT1BEePwSmEFg1BSGcllKL9VRHFLNIz+v7?= =?us-ascii?Q?cmZiPQRN39uh+TS7yoTIJBNWSXAqzPiuTG64BwxP1yfwBtuzwQrzAOQ33qsO?= =?us-ascii?Q?7HZKwTNhQjB0dFXVUzokYdCBBZ4lDkHA8rFVo39bVbuH67pFMl+FDW6Vc4lT?= =?us-ascii?Q?g8JOOIM6oRYaeQfkivzVSTR8D3TDyj3uyKyxJ+CLiBV4bbW5UBjufedDf9gf?= =?us-ascii?Q?f9egoYyl4DqISOwQ+6wX4XT3BeN2BMZBIZapggJV1MfDwCZf7t2iRX0tq4/9?= =?us-ascii?Q?RSmOJ24IHKbwSr/p8vgs4e1uiL16YIKiZhSv4op0jRnZ270VItqarFM1cT67?= =?us-ascii?Q?/1ZgFIyyYm8eKALIRbU4hy7kb1lwWvcCLOa3HOAJ?= X-MS-Exchange-CrossTenant-Network-Message-Id: 0e500a29-28a1-4a93-357d-08dae954bc23 X-MS-Exchange-CrossTenant-AuthSource: MN0PR11MB6206.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 29 Dec 2022 04:25:37.1773 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: LX/dy8qc8fHBJIO5FhujRCiDg89rrlPicKrc7EK9JgcZQ3WAwCMIb0B6w5KosnBgNphPnv87+k9JIf20hBQhiA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA2PR11MB4939 X-OriginatorOrg: intel.com Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2022-12-28 at 00:14:00 +0800, Tio Zhang wrote: > Knowing who the parent is might be useful for debugging. > For example, we can sometimes resolve kernel hung tasks by stopping > the person who begins those hung tasks. > With the parent's name printed in sched_show_task(), > it might be helpful to let people know which "service" should be operated. > > Signed-off-by: Tio Zhang > --- > kernel/sched/core.c | 9 ++++++--- > 1 file changed, 6 insertions(+), 3 deletions(-) > > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > index cb2aa2b54c7a..6f4aef0fed58 100644 > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -8854,6 +8854,7 @@ void sched_show_task(struct task_struct *p) > { > unsigned long free = 0; > int ppid; > + char pcomm[TASK_COMM_LEN]; > > if (!try_get_task_stack(p)) > return; > @@ -8867,11 +8868,13 @@ void sched_show_task(struct task_struct *p) > #endif > ppid = 0; > rcu_read_lock(); > - if (pid_alive(p)) > + if (pid_alive(p)) { > ppid = task_pid_nr(rcu_dereference(p->real_parent)); > + get_task_comm(pcomm, rcu_dereference(p->real_parent)); Maybe struct task_struct *parent = rcu_dereference(p->real_parent); and use parent directly to get its pid and comm? Maybe off-topic, what if the parent is a kernel thread/worker? It might have extra name information such as kthread->full_name or worker->desc according to proc_task_name(). thanks,