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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?b+LyqAOk9BDztNDd4KJt8WEUSRmaCgE8eIZIvAm/1RBnuM3iv+G3Xl5yDgZS?= =?us-ascii?Q?c5cAFjxLuKN2qr68S00r6cmqz7jM45UdH/3oaSVMeimz5kbGXB8h3rnSp89G?= =?us-ascii?Q?nUbBDBVCMJf8STy7gxSi0GUbDYgdNbR21tPdSb4BIKLcdoL/c8WaH5FD5XiR?= =?us-ascii?Q?zW9kjmkem/Ls9hGWBehR5acVAlAUpD/K/dV9oEZ37wfNP5eQ+sDe18tp8xMl?= =?us-ascii?Q?HDEgHOJHnEh+bY3GpqyLg/hYNmXcQtMw3CPAFhqdbMdqC64jbLbvcgv6zr9j?= =?us-ascii?Q?m6C18uZEnGNkBk4bJUnorgPiyYk6sTOaOQpWoi75tsHq2nyyKDGO90o6yuzb?= =?us-ascii?Q?NHwj1LT2ldpCRgTgQAA6kRzm2ovFdfT9SCwr3Y+TEb4QqWkC0y83O6Qw7LLB?= =?us-ascii?Q?NKGbggibVjWt6WijBjOIYtzaUxIbchk14ylheA69N59Or4yrXfJ5m1bqNC3G?= =?us-ascii?Q?ZQnAXG3snj11AXxxZgp3rly/ASttexsvxD8bYwtTkeWtSLqFrVy4SCy+kSFx?= =?us-ascii?Q?vaDABtmxtkXQufW21nrYHvpTGSbkztwdAWMzLAB7nd0DOdJOyiz3BIWk7Ag1?= =?us-ascii?Q?+B4Zd8VoxYo89LRPL/cy3qaJ58fGUPSODkN6NtY/NVILRmsKqKxq7RZfSBvj?= =?us-ascii?Q?YxvgHQDQxarCT1O8B2iYbJU3L/z2M/hYYFw8gwNatsOvJ7MAUJVfRNbkbFhz?= =?us-ascii?Q?JK/IOFZxBkeT+J2YXD7TlBuM8cTQboT+i/nLFz/MVHS0PZUwFWvaIxr3FtnL?= =?us-ascii?Q?Iile+Fm60ZIsmJEj87SJSGpQBB5ud/x87QUKr6vF3LJR9OP1+4Gv3cUPM1kg?= =?us-ascii?Q?ayCWMTPZpo4ZNsjpCOvJ1zjKpZ+KqFiyADyIu8wuN12ixeB6WzJXEl9Qn6XP?= =?us-ascii?Q?gdJLGZexCfZCxVqShgqnxeJS4Rg9haqeqHwIKoa5duTnHQWh6TKq4Zr5Mw2v?= =?us-ascii?Q?9Fh2EAEslDiRSjn0F+TesfEMc9jhHAz2F5t7rZF7O/H6krrBUOrrC34R/Ypz?= =?us-ascii?Q?jBOLH3dkgt70Zz/9+f/R1FYD5xc8p7LNtBcsBAEoQ0laG460ceyNHVnmXA6X?= =?us-ascii?Q?fdit/fDnpKErsEe5L0eqt4NUQ43WPXxInxDwP4NE9lT2qVzKblDXqWR8eDJg?= =?us-ascii?Q?z2FEla1Lk8mNN0mzcsOEMVNzwNKXwNZ1QLV0RfP9gckzpnO4rr9WiSQmaLSM?= =?us-ascii?Q?jYpuWW0+VcID5lLbjtBv5JpE9AuycHwcpqKzs1S8VpgY26nLg1H5uLyozzUr?= =?us-ascii?Q?B+27ygPdmiWUQgX7Ym89ooXi3NY/ovlWbsznBtTX3+Zd/0rIaSSuNdijFD2x?= =?us-ascii?Q?LheXU5wxRgnQBgy+oC0w6Islk7B2cWPaeqwYe4eqZxl8dnf3Aw61QMt6n2Hl?= =?us-ascii?Q?B4a6Yk8TCzHr1zHLwIiBOspSw2ydvKDjuXc/To/9yEHvKYPClHhATc/2b3A0?= =?us-ascii?Q?ZkMMExilUbRkZHknlg+ueIlCdc9PFoln1arcBhvPdiKDfwr2JqCLmCIEVZXf?= =?us-ascii?Q?iaRVIdwzlMa5B6jkCDdRaQ9coN+D+z+sirg/woY7PbuamTVRZrOOvH7e7Mx2?= =?us-ascii?Q?8vlc4USVYr+wHaQAnD4g4q7mkERZOZhsnQWjIam3KfrKYDdEa706pQNMRm4p?= =?us-ascii?Q?QzdPCOp3i72XITKU7e4eFBGB5nQTtfLCIGRgelkl8z41RjAxu80i9iR+jCyV?= =?us-ascii?Q?YBJ5p3zOGhNAAtot5vX9uVMqYLjI2G9UNkL6VCFuQfckEWbE/QtndMEq5dAp?= =?us-ascii?Q?oNigvqATMg=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 897eb2d0-75c5-4989-511e-08df07660295 X-MS-Exchange-CrossTenant-AuthSource: DM6PR12MB4827.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 31 Aug 2026 13:44:42.2934 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: bRMO56eqj9Jw3nYGp9f02+JbiaS1Hcj/hIei4iDPdrcBJkxMlmCPydAhjsXqznHkbjLn4dVwXZfjHRRpE6E+bg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW4PR12MB6755 Proxy execution splits the scheduling context (the donor) from the execution context (the lock owner). sched_ext needs to observe that split at three points in __schedule(): - whether a blocked EXT task can be retained on the runqueue as a donor, - when a donor's scheduling context starts driving a lock owner, - once proxy resolution has settled for the current pick. Introduce scx_allow_proxy_exec(), scx_proxy_donor_start() and scx_proxy_resolved(), and add their call sites in __schedule(). The implementations are empty here and are filled in by the sched_ext changes that follow, so that all the sched core changes needed by proxy execution stay together in the preparatory patches. SCHED_PROXY_EXEC still depends on !SCHED_CLASS_EXT, so the new hooks are inert: they are compiled out with CONFIG_SCHED_CLASS_EXT=n and unreachable otherwise. This is a preparatory change to support proxy execution with sched_ext. No functional change. Signed-off-by: Andrea Righi --- kernel/sched/core.c | 12 +++++++----- kernel/sched/ext/ext.c | 13 +++++++++++++ kernel/sched/ext/ext.h | 6 ++++++ 3 files changed, 26 insertions(+), 5 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index bb79fcfa21cd2..d578dd635f2eb 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -7217,13 +7217,12 @@ static void __sched notrace __schedule(int sched_mode) } } else if (!preempt && prev_state) { /* - * We pass task_is_blocked() as the should_block arg - * in order to keep mutex-blocked tasks on the runqueue - * for slection with proxy-exec (without proxy-exec - * task_is_blocked() will always be false). + * Keep mutex-blocked tasks on the runqueue for proxy execution + * only when their scheduling class allows it. Without proxy + * execution, task_is_blocked() always returns false. */ try_to_block_task(rq, prev, &prev_state, - !task_is_blocked(prev)); + !task_is_blocked(prev) || !scx_allow_proxy_exec(prev)); switch_count = &prev->nvcsw; } @@ -7244,6 +7243,7 @@ static void __sched notrace __schedule(int sched_mode) } if (next == rq->idle) { zap_balance_callbacks(rq); + scx_proxy_resolved(rq); goto keep_resched; } } @@ -7264,6 +7264,8 @@ static void __sched notrace __schedule(int sched_mode) donor->sched_class->put_prev_task(rq, donor, donor); donor->sched_class->set_next_task(rq, donor, true); } + scx_proxy_donor_start(rq); + scx_proxy_resolved(rq); } else { rq_set_donor(rq, next); } diff --git a/kernel/sched/ext/ext.c b/kernel/sched/ext/ext.c index 00c368e2fc82d..f3e59f4fad4ac 100644 --- a/kernel/sched/ext/ext.c +++ b/kernel/sched/ext/ext.c @@ -24,6 +24,11 @@ DEFINE_RAW_SPINLOCK(scx_sched_lock); +bool scx_allow_proxy_exec(const struct task_struct *p) +{ + return true; +} + /* * NOTE: sched_ext is in the process of growing multiple scheduler support and * scx_root usage is in a transitional state. Naked dereferences are safe if the @@ -1079,6 +1084,10 @@ static void schedule_deferred_locked(struct rq *rq) schedule_deferred(rq); } +void scx_proxy_resolved(struct rq *rq) +{ +} + void schedule_dsq_reenq(struct scx_sched *sch, struct scx_dispatch_q *dsq, u64 reenq_flags, struct rq *locked_rq) { @@ -3062,6 +3071,10 @@ static void set_next_task_scx(struct rq *rq, struct task_struct *p, bool first) } } +void scx_proxy_donor_start(struct rq *rq) +{ +} + static enum scx_cpu_preempt_reason preempt_reason_from_class(const struct sched_class *class) { diff --git a/kernel/sched/ext/ext.h b/kernel/sched/ext/ext.h index 0b7fc46aee08c..859b9261a8a6b 100644 --- a/kernel/sched/ext/ext.h +++ b/kernel/sched/ext/ext.h @@ -20,6 +20,9 @@ void scx_rq_deactivate(struct rq *rq); int scx_check_setscheduler(struct task_struct *p, int policy); bool task_should_scx(int policy); bool scx_allow_ttwu_queue(const struct task_struct *p); +bool scx_allow_proxy_exec(const struct task_struct *p); +void scx_proxy_donor_start(struct rq *rq); +void scx_proxy_resolved(struct rq *rq); void init_sched_ext_class(void); static inline u32 scx_cpuperf_target(s32 cpu) @@ -54,6 +57,9 @@ static inline void scx_rq_deactivate(struct rq *rq) {} static inline int scx_check_setscheduler(struct task_struct *p, int policy) { return 0; } static inline bool task_on_scx(const struct task_struct *p) { return false; } static inline bool scx_allow_ttwu_queue(const struct task_struct *p) { return true; } +static inline bool scx_allow_proxy_exec(const struct task_struct *p) { return true; } +static inline void scx_proxy_donor_start(struct rq *rq) {} +static inline void scx_proxy_resolved(struct rq *rq) {} static inline void init_sched_ext_class(void) {} #endif /* CONFIG_SCHED_CLASS_EXT */ -- 2.55.0