Merge tag 'efi-efivars-removal-for-v5.20' of git://git.kernel.org/pub/scm/linux/kerne...

[linux-2.6-block.git] / kernel / sched / core.c

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 5555e49c4e120cdfab2803393ec0f02879741815..189999007f327c27ceae655c527d8fec08dc92e9 100644 (file)
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -91,7 +91,7 @@
 #include "stats.h"
 
 #include "../workqueue_internal.h"
-#include "../../fs/io-wq.h"
+#include "../../io_uring/io-wq.h"
 #include "../smpboot.h"
 
 /*
@@ -4262,6 +4262,38 @@ int task_call_func(struct task_struct *p, task_call_f func, void *arg)
        return ret;
 }
 
+/**
+ * cpu_curr_snapshot - Return a snapshot of the currently running task
+ * @cpu: The CPU on which to snapshot the task.
+ *
+ * Returns the task_struct pointer of the task "currently" running on
+ * the specified CPU.  If the same task is running on that CPU throughout,
+ * the return value will be a pointer to that task's task_struct structure.
+ * If the CPU did any context switches even vaguely concurrently with the
+ * execution of this function, the return value will be a pointer to the
+ * task_struct structure of a randomly chosen task that was running on
+ * that CPU somewhere around the time that this function was executing.
+ *
+ * If the specified CPU was offline, the return value is whatever it
+ * is, perhaps a pointer to the task_struct structure of that CPU's idle
+ * task, but there is no guarantee.  Callers wishing a useful return
+ * value must take some action to ensure that the specified CPU remains
+ * online throughout.
+ *
+ * This function executes full memory barriers before and after fetching
+ * the pointer, which permits the caller to confine this function's fetch
+ * with respect to the caller's accesses to other shared variables.
+ */
+struct task_struct *cpu_curr_snapshot(int cpu)
+{
+       struct task_struct *t;
+
+       smp_mb(); /* Pairing determined by caller's synchronization design. */
+       t = rcu_dereference(cpu_curr(cpu));
+       smp_mb(); /* Pairing determined by caller's synchronization design. */
+       return t;
+}
+
 /**
  * wake_up_process - Wake up a specific process
  * @p: The process to be woken up.
@@ -6563,7 +6595,7 @@ void __sched schedule_idle(void)
        } while (need_resched());
 }
 
-#if defined(CONFIG_CONTEXT_TRACKING) && !defined(CONFIG_HAVE_CONTEXT_TRACKING_OFFSTACK)
+#if defined(CONFIG_CONTEXT_TRACKING_USER) && !defined(CONFIG_HAVE_CONTEXT_TRACKING_USER_OFFSTACK)
 asmlinkage __visible void __sched schedule_user(void)
 {
        /*