percpu active_thread using gs segment

TESTED: As per previous commit
Message-Id: <20230924052824.449219-4-damien@zamaudio.com>

7 files changed, 8 insertions, 10 deletions

diff --git a/kern/ipc_sched.c b/kern/ipc_sched.c
index be82971b..4519c654 100644
--- a/kern/ipc_sched.c
+++ b/kern/ipc_sched.c
@@ -233,7 +233,7 @@ thread_handoff(
 	/*
 	 *	stack_handoff is machine-dependent.  It does the
 	 *	machine-dependent components of a context-switch, like
-	 *	changing address spaces.  It updates active_threads.
+	 *	changing address spaces.  It updates active_thread.
 	 */
 
 	stack_handoff(old, new);
diff --git a/kern/machine.c b/kern/machine.c
index 0aa0f3c6..87fbc4d1 100644
--- a/kern/machine.c
+++ b/kern/machine.c
@@ -635,7 +635,7 @@ void processor_doshutdown(processor_t processor)
 	 */
 	PMAP_DEACTIVATE_KERNEL(cpu);
 #ifndef MIGRATING_THREADS
-	active_threads[cpu] = THREAD_NULL;
+	percpu_array[cpu].active_thread = THREAD_NULL;
 #endif
 	cpu_down(cpu);
 	thread_wakeup((event_t)processor);
diff --git a/kern/sched_prim.c b/kern/sched_prim.c
index 6617db7c..5ee0521a 100644
--- a/kern/sched_prim.c
+++ b/kern/sched_prim.c
@@ -806,7 +806,7 @@ boolean_t thread_invoke(
 	/*
 	 *	switch_context is machine-dependent.  It does the
 	 *	machine-dependent components of a context-switch, like
-	 *	changing address spaces.  It updates active_threads.
+	 *	changing address spaces.  It updates active_thread.
 	 *	It returns only if a continuation is not supplied.
 	 */
 	counter(c_thread_invoke_csw++);
diff --git a/kern/startup.c b/kern/startup.c
index 88608c7d..13acb850 100644
--- a/kern/startup.c
+++ b/kern/startup.c
@@ -300,7 +300,7 @@ void cpu_launch_first_thread(thread_t th)
 
 	PMAP_ACTIVATE_KERNEL(mycpu);
 
-	active_threads[mycpu] = th;
+	percpu_assign(active_thread, th);
 	active_stacks[mycpu] = th->kernel_stack;
 	thread_lock(th);
 	th->state &= ~TH_UNINT;
diff --git a/kern/thread.c b/kern/thread.c
index 9bbe8342..c397de84 100644
--- a/kern/thread.c
+++ b/kern/thread.c
@@ -69,7 +69,6 @@
 #include <machine/pcb.h>
 #include <machine/thread.h>		/* for MACHINE_STACK */
 
-thread_t active_threads[NCPUS];
 vm_offset_t active_stacks[NCPUS];
 
 struct kmem_cache thread_cache;
@@ -2572,7 +2571,7 @@ kern_return_t processor_set_stack_usage(
 			stack = thread->kernel_stack;
 
 			for (cpu = 0; cpu < smp_get_numcpus(); cpu++)
-				if (active_threads[cpu] == thread) {
+				if (percpu_array[cpu].active_thread == thread) {
 					stack = active_stacks[cpu];
 					break;
 				}
diff --git a/kern/thread.h b/kern/thread.h
index bf07828a..144160d5 100644
--- a/kern/thread.h
+++ b/kern/thread.h
@@ -269,7 +269,6 @@ typedef	mach_port_t *thread_array_t;
 #endif	/* _KERN_KERN_TYPES_H_ */
 
 
-extern thread_t		active_threads[NCPUS];	/* active threads */
 extern vm_offset_t	active_stacks[NCPUS];	/* active kernel stacks */
 
 #ifdef KERNEL
@@ -415,7 +414,7 @@ extern void		thread_unfreeze(
  *	designate this by defining CURRENT_THREAD.
  */
 #ifndef	CURRENT_THREAD
-#define current_thread()	(active_threads[cpu_number()])
+#define current_thread()	(percpu_get(thread_t, active_thread))
 #endif	/* CURRENT_THREAD */
 
 #define	current_stack()		(active_stacks[cpu_number()])
diff --git a/kern/timer.c b/kern/timer.c
index 7d029b7c..13dfc207 100644
--- a/kern/timer.c
+++ b/kern/timer.c
@@ -132,7 +132,7 @@ time_trap_uentry(unsigned ts)
 	/*
 	 *	Record new timer.
 	 */
-	mytimer = &(active_threads[mycpu]->system_timer);
+	mytimer = &(current_thread()->system_timer);
 	current_timer[mycpu] = mytimer;
 	mytimer->tstamp = ts;
 }
@@ -170,7 +170,7 @@ time_trap_uexit(int ts)
 		timer_normalize(mytimer);	/* SYSTEMMODE */
 	}
 
-	mytimer = &(active_threads[mycpu]->user_timer);
+	mytimer = &(current_thread()->user_timer);
 
 	/*
 	 *	Record new timer.