[coreboot-gerrit] Change in coreboot[master]: arch/x86,cpu/x86,lib/thread: Remove usage of cpu_info from lib/thread

[Raul Rangel (Code Review)]

Raul Rangel has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/58199 )

Change subject: arch/x86,cpu/x86,lib/thread: Remove usage of cpu_info from lib/thread
......................................................................

arch/x86,cpu/x86,lib/thread: Remove usage of cpu_info from lib/thread

We only ever start and execute threads on the BSP. By explicitly
checking to see if the CPU is the BSP we can remove the dependency on
cpu_info. With this change we can in theory enable threads in bootblock
and romstage.

BUG=b:194391185, b:179699789
TEST=Boot guybrush to OS and verify coop multithreading still works

Suggested-by: Julius Werner 
Signed-off-by: Raul E Rangel 
Change-Id: Iea4622d52c36d529e100b7ea55f32c334acfdf3e
---
M src/arch/x86/include/arch/cpu.h
M src/cpu/x86/cpu_info.S.inc
M src/cpu/x86/lapic/lapic_cpu_init.c
M src/cpu/x86/mp_init.c
M src/include/thread.h
M src/lib/thread.c
6 files changed, 14 insertions(+), 24 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/99/58199/1

diff --git a/src/arch/x86/include/arch/cpu.h b/src/arch/x86/include/arch/cpu.h
index 8e96fae..9a3b63d 100644
--- a/src/arch/x86/include/arch/cpu.h
+++ b/src/arch/x86/include/arch/cpu.h
@@ -231,9 +231,6 @@
 struct cpu_info {
    struct device *cpu;
    size_t index;
-#if CONFIG(COOP_MULTITASKING)
-	struct thread *thread;
-#endif
 };

/*
diff --git a/src/cpu/x86/cpu_info.S.inc b/src/cpu/x86/cpu_info.S.inc
index dffd1bc..fc3e26d 100644
--- a/src/cpu/x86/cpu_info.S.inc
+++ b/src/cpu/x86/cpu_info.S.inc
@@ -2,9 +2,6 @@

/* Push struct cpu_info */
 .macro push_cpu_info index=$0
-#if CONFIG(COOP_MULTITASKING)
-	push	$0	/* *thread */
-#endif
    push	\index	/* index */
    push	$0	/* *cpu */
 .endm
diff --git a/src/cpu/x86/lapic/lapic_cpu_init.c b/src/cpu/x86/lapic/lapic_cpu_init.c
index e141ad8..d463c69 100644
--- a/src/cpu/x86/lapic/lapic_cpu_init.c
+++ b/src/cpu/x86/lapic/lapic_cpu_init.c
@@ -253,7 +253,6 @@
    info->index = index;
    info->cpu   = cpu;
    cpu_add_map_entry(info->index);
-	thread_init_cpu_info_non_bsp(info);

/* Advertise the new stack and index to start_cpu */
    secondary_stack = stack_top;
diff --git a/src/cpu/x86/mp_init.c b/src/cpu/x86/mp_init.c
index 123b2b5..497ed3c 100644
--- a/src/cpu/x86/mp_init.c
+++ b/src/cpu/x86/mp_init.c
@@ -193,7 +193,6 @@
    info->cpu = cpus_dev[cpu];

cpu_add_map_entry(info->index);
-	thread_init_cpu_info_non_bsp(info);

/* Fix up APIC id with reality. */
    info->cpu->path.apic.apic_id = lapicid();
diff --git a/src/include/thread.h b/src/include/thread.h
index cb085b5..62c6283 100644
--- a/src/include/thread.h
+++ b/src/include/thread.h
@@ -73,11 +73,6 @@
 void thread_mutex_lock(struct thread_mutex *mutex);
 void thread_mutex_unlock(struct thread_mutex *mutex);

-static inline void thread_init_cpu_info_non_bsp(struct cpu_info *ci)
-{
-	ci->thread = NULL;
-}
-
 /* Architecture specific thread functions. */
 asmlinkage void switch_to_thread(uintptr_t new_stack, uintptr_t *saved_stack);
 /* Set up the stack frame for a new thread so that a switch_to_thread() call
@@ -96,8 +91,6 @@
 }
 static inline void thread_coop_enable(void) {}
 static inline void thread_coop_disable(void) {}
-struct cpu_info;
-static inline void thread_init_cpu_info_non_bsp(struct cpu_info *ci) { }

static inline void thread_mutex_lock(struct thread_mutex *mutex) {}

diff --git a/src/lib/thread.c b/src/lib/thread.c
index 9008147e..8cc2637 100644
--- a/src/lib/thread.c
+++ b/src/lib/thread.c
@@ -4,10 +4,10 @@
 #include <stddef.h>
 #include <stdint.h>
 #include <stdlib.h>
-#include <arch/cpu.h>
 #include <bootstate.h>
 #include <commonlib/bsd/compiler.h>
 #include <console/console.h>
+#include <smp/node.h>
 #include <thread.h>
 #include <timer.h>

@@ -27,17 +27,24 @@
 static struct thread *runnable_threads;
 static struct thread *free_threads;

+static struct thread *active_thread;
+
 static inline int thread_can_yield(const struct thread *t)
 {
    return (t != NULL && t->can_yield > 0);
 }

+static inline void set_current_thread(struct thread *t)
+{
+	active_thread = t;
+}
+
 static inline struct thread *current_thread(void)
 {
-	if (!initialized)
+	if (!initialized || !boot_cpu())
    	return NULL;

-	return cpu_info()->thread;
+	return active_thread;
 }

static inline int thread_list_empty(struct thread **list)
@@ -108,7 +115,6 @@
 static void schedule(struct thread *t)
 {
    struct thread *current = current_thread();
-	struct cpu_info *ci = cpu_info();

/* If t is NULL need to find new runnable thread. */
    if (t == NULL) {
@@ -123,7 +129,7 @@
    if (t->handle)
    	t->handle->state = THREAD_STARTED;

-	ci->thread = t;
+	set_current_thread(t);

switch_to_thread(t->stack_current, &current->stack_current);
 }
@@ -239,18 +245,17 @@
    int i;
    struct thread *t;
    u8 *stack_top;
-	struct cpu_info *ci;

-	if (initialized)
+	if (initialized || !boot_cpu())
    	return;

t = &all_threads[0];
-	ci = cpu_info();
-	ci->thread = t;
    t->stack_orig = (uintptr_t)NULL; /* We never free the main thread */
    t->id = 0;
    t->can_yield = 1;

+	set_current_thread(t);
+
    stack_top = &thread_stacks[CONFIG_STACK_SIZE];
    for (i = 1; i < TOTAL_NUM_THREADS; i++) {
    	t = &all_threads[i];