From 26f80681a09b95fd64bcf33d02e258e78a30842b Mon Sep 17 00:00:00 2001 From: Gabriele Monaco Date: Wed, 5 Mar 2025 15:03:54 +0100 Subject: sched: Add sched tracepoints for RV task model Add the following tracepoints: * sched_entry(bool preempt, ip) Called while entering __schedule * sched_exit(bool is_switch, ip) Called while exiting __schedule * sched_set_state(task, curr_state, state) Called when a task changes its state (to and from running) These tracepoints are useful to describe the Linux task model and are adapted from the patches by Daniel Bristot de Oliveira (https://bristot.me/linux-task-model/). Cc: Ingo Molnar Cc: Masami Hiramatsu Cc: Juri Lelli Link: https://lore.kernel.org/20250305140406.350227-2-gmonaco@redhat.com Signed-off-by: Gabriele Monaco Acked-by: Peter Zijlstra (Intel) Signed-off-by: Steven Rostedt (Google) --- include/linux/rv.h | 2 +- include/linux/sched.h | 16 ++++++++++++++++ 2 files changed, 17 insertions(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/rv.h b/include/linux/rv.h index 8883b41d88ec..55d458be53a4 100644 --- a/include/linux/rv.h +++ b/include/linux/rv.h @@ -7,7 +7,7 @@ #ifndef _LINUX_RV_H #define _LINUX_RV_H -#define MAX_DA_NAME_LEN 24 +#define MAX_DA_NAME_LEN 32 #ifdef CONFIG_RV /* diff --git a/include/linux/sched.h b/include/linux/sched.h index 9632e3318e0d..45a61a0b9790 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -46,6 +46,7 @@ #include #include #include +#include #include /* task_struct member predeclarations (sorted alphabetically): */ @@ -186,6 +187,12 @@ struct user_event_mm; # define debug_rtlock_wait_restore_state() do { } while (0) #endif +#define trace_set_current_state(state_value) \ + do { \ + if (tracepoint_enabled(sched_set_state_tp)) \ + __trace_set_current_state(state_value); \ + } while (0) + /* * set_current_state() includes a barrier so that the write of current->__state * is correctly serialised wrt the caller's subsequent test of whether to @@ -226,12 +233,14 @@ struct user_event_mm; #define __set_current_state(state_value) \ do { \ debug_normal_state_change((state_value)); \ + trace_set_current_state(state_value); \ WRITE_ONCE(current->__state, (state_value)); \ } while (0) #define set_current_state(state_value) \ do { \ debug_normal_state_change((state_value)); \ + trace_set_current_state(state_value); \ smp_store_mb(current->__state, (state_value)); \ } while (0) @@ -247,6 +256,7 @@ struct user_event_mm; \ raw_spin_lock_irqsave(¤t->pi_lock, flags); \ debug_special_state_change((state_value)); \ + trace_set_current_state(state_value); \ WRITE_ONCE(current->__state, (state_value)); \ raw_spin_unlock_irqrestore(¤t->pi_lock, flags); \ } while (0) @@ -282,6 +292,7 @@ struct user_event_mm; raw_spin_lock(¤t->pi_lock); \ current->saved_state = current->__state; \ debug_rtlock_wait_set_state(); \ + trace_set_current_state(TASK_RTLOCK_WAIT); \ WRITE_ONCE(current->__state, TASK_RTLOCK_WAIT); \ raw_spin_unlock(¤t->pi_lock); \ } while (0); @@ -291,6 +302,7 @@ struct user_event_mm; lockdep_assert_irqs_disabled(); \ raw_spin_lock(¤t->pi_lock); \ debug_rtlock_wait_restore_state(); \ + trace_set_current_state(current->saved_state); \ WRITE_ONCE(current->__state, current->saved_state); \ current->saved_state = TASK_RUNNING; \ raw_spin_unlock(¤t->pi_lock); \ @@ -327,6 +339,10 @@ extern void io_schedule_finish(int token); extern long io_schedule_timeout(long timeout); extern void io_schedule(void); +/* wrapper function to trace from this header file */ +DECLARE_TRACEPOINT(sched_set_state_tp); +extern void __trace_set_current_state(int state_value); + /** * struct prev_cputime - snapshot of system and user cputime * @utime: time spent in user mode -- cgit v1.2.3