Merge pull request torvalds#246 from tavip/no-syscall-threads

Direct host calls - v2

arch/lkl/include/asm/cpu.h

@@ -0,0 +1,14 @@
+#ifndef _ASM_LKL_CPU_H
+#define _ASM_LKL_CPU_H
+
+int lkl_cpu_get(void);
+void lkl_cpu_put(void);
+int lkl_cpu_try_run_irq(int irq);
+int lkl_cpu_init(void);
+void lkl_cpu_shutdown(void);
+void lkl_cpu_wait_shutdown(void);
+void lkl_cpu_wakeup(void);
+void lkl_cpu_change_owner(lkl_thread_t owner);
+void lkl_cpu_set_irqs_pending(void);
+
+#endif /* _ASM_LKL_CPU_H */

arch/lkl/include/asm/irq.h

@@ -2,7 +2,10 @@
 #define _ASM_LKL_IRQ_H
 
 #define IRQ_STATUS_BITS		(sizeof(long) * 8)
-#define NR_IRQS			((int)IRQ_STATUS_BITS * IRQ_STATUS_BITS)
+#define NR_IRQS			((int)(IRQ_STATUS_BITS * IRQ_STATUS_BITS))
+
+void run_irqs(void);
+void set_irq_pending(int irq);
 
 #include <uapi/asm/irq.h>
 

arch/lkl/include/asm/setup.h

@@ -3,8 +3,4 @@
 
 #define COMMAND_LINE_SIZE 4096
 
-#ifndef __ASSEMBLY__
-void wakeup_cpu(void);
-#endif
-
 #endif

arch/lkl/include/asm/syscalls.h

@@ -1,8 +1,8 @@
 #ifndef _ASM_LKL_SYSCALLS_H
 #define _ASM_LKL_SYSCALLS_H
 
-int initial_syscall_thread(void *);
-void free_initial_syscall_thread(void);
+int syscalls_init(void);
+void syscalls_cleanup(void);
 long lkl_syscall(long no, long *params);
 
 #define sys_mmap sys_mmap_pgoff

arch/lkl/include/asm/thread_info.h

@@ -18,6 +18,7 @@ struct thread_info {
 	int preempt_count;
 	mm_segment_t addr_limit;
 	struct lkl_sem *sched_sem;
+	struct lkl_jmp_buf sched_jb;
 	bool dead;
 	lkl_thread_t tid;
 	struct task_struct *prev_sched;
@@ -46,7 +47,7 @@ static inline struct thread_info *current_thread_info(void)
 unsigned long *alloc_thread_stack_node(struct task_struct *, int node);
 void free_thread_stack(unsigned long *);
 
-int threads_init(void);
+void threads_init(void);
 void threads_cleanup(void);
 
 #define TIF_SYSCALL_TRACE		0
@@ -56,6 +57,24 @@ void threads_cleanup(void);
 #define TIF_RESTORE_SIGMASK		4
 #define TIF_MEMDIE			5
 #define TIF_NOHZ			6
+#define TIF_SCHED_JB			7
+#define TIF_SCHED_EXIT			8
+#define TIF_HOST_THREAD			9
+
+static inline void set_ti_thread_flag(struct thread_info *ti, int flag);
+
+static inline int thread_set_sched_jmp(void)
+{
+	set_ti_thread_flag(current_thread_info(), TIF_SCHED_JB);
+	return lkl_ops->jmp_buf_set(&current_thread_info()->sched_jb);
+}
+
+static inline void thread_set_sched_exit(void)
+{
+	set_ti_thread_flag(current_thread_info(), TIF_SCHED_EXIT);
+}
+
+void switch_to_host_task(struct task_struct *);
 
 #define __HAVE_THREAD_FUNCTIONS
 

arch/lkl/include/asm/unistd.h

@@ -1,6 +1,5 @@
 #include <uapi/asm/unistd.h>
 
-__SYSCALL(__NR_create_syscall_thread, sys_create_syscall_thread)
 __SYSCALL(__NR_virtio_mmio_device_add, sys_virtio_mmio_device_add)
 
 #define __SC_ASCII(t, a) #t "," #a

arch/lkl/include/uapi/asm/host_ops.h

@@ -5,6 +5,9 @@
 struct lkl_mutex;
 struct lkl_sem;
 typedef unsigned long lkl_thread_t;
+struct lkl_jmp_buf {
+	unsigned long buf[32];
+};
 
 /**
  * lkl_host_operations - host operations used by the Linux kernel
@@ -25,7 +28,8 @@ typedef unsigned long lkl_thread_t;
  * @sem_up - perform an up operation on the semaphore
  * @sem_down - perform a down operation on the semaphore
  *
- * @mutex_alloc - allocate and initialize a host mutex
+ * @mutex_alloc - allocate and initialize a host mutex; the recursive parameter
+ * determines if the mutex is recursive or not
  * @mutex_free - free a host mutex
  * @mutex_lock - acquire the mutex
  * @mutex_unlock - release the mutex
@@ -77,7 +81,7 @@ struct lkl_host_operations {
 	void (*sem_up)(struct lkl_sem *sem);
 	void (*sem_down)(struct lkl_sem *sem);
 
-	struct lkl_mutex *(*mutex_alloc)(void);
+	struct lkl_mutex *(*mutex_alloc)(int recursive);
 	void (*mutex_free)(struct lkl_mutex *mutex);
 	void (*mutex_lock)(struct lkl_mutex *mutex);
 	void (*mutex_unlock)(struct lkl_mutex *mutex);
@@ -86,6 +90,8 @@ struct lkl_host_operations {
 	void (*thread_detach)(void);
 	void (*thread_exit)(void);
 	int (*thread_join)(lkl_thread_t tid);
+	lkl_thread_t (*thread_self)(void);
+	int (*thread_equal)(lkl_thread_t a, lkl_thread_t b);
 
 	int (*tls_alloc)(unsigned int *key, void (*destructor)(void *));
 	int (*tls_free)(unsigned int key);
@@ -106,6 +112,9 @@ struct lkl_host_operations {
 			    int write);
 
 	long (*gettid)(void);
+
+	int (*jmp_buf_set)(struct lkl_jmp_buf *jmpb);
+	void (*jmp_buf_longjmp)(struct lkl_jmp_buf *jmpb, int val);
 };
 
 /**
@@ -127,4 +136,7 @@ int lkl_start_kernel(struct lkl_host_operations *lkl_ops,
  */
 int lkl_is_running(void);
 
+int lkl_printf(const char *, ...);
+void lkl_bug(const char *, ...);
+
 #endif

arch/lkl/include/uapi/asm/unistd.h

@@ -8,5 +8,4 @@
 
 #include <asm-generic/unistd.h>
 
-#define __NR_create_syscall_thread		(__NR_arch_specific_syscall + 0)
-#define __NR_virtio_mmio_device_add		(__NR_arch_specific_syscall + 1)
+#define __NR_virtio_mmio_device_add		(__NR_arch_specific_syscall + 0)

arch/lkl/kernel/Makefile

@@ -1,3 +1,4 @@
 extra-y := vmlinux.lds
 
-obj-y = setup.o threads.o irq.o time.o syscalls.o misc.o console.o syscalls_32.o
+obj-y = setup.o threads.o irq.o time.o syscalls.o misc.o console.o \
+	syscalls_32.o cpu.o