[PATCH] m68k: convert thread flags to use bit fields

Remove task_work structure, use the standard thread flags functions and use
shifts in entry.S to test the thread flags.  Add a few local labels to entry.S
to allow gas to generate short jumps.

Finally it changes a number of inline functions in thread_info.h to macros to
delay the current_thread_info() usage, which requires on m68k a structure
(task_struct) not yet defined at this point.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

3 files changed, 22 insertions, 118 deletions

diff --git a/include/asm-m68k/processor.h b/include/asm-m68k/processor.h
index 84b4b26..7982285 100644
--- a/include/asm-m68k/processor.h
+++ b/include/asm-m68k/processor.h
@@ -56,17 +56,6 @@ static inline void wrusp(unsigned long usp)
 #endif
 #define TASK_UNMAPPED_ALIGN(addr, off)	PAGE_ALIGN(addr)
 
-struct task_work {
-	unsigned char sigpending;
-	unsigned char notify_resume;	/* request for notification on
-					   userspace execution resumption */
-	char          need_resched;
-	unsigned char delayed_trace;	/* single step a syscall */
-	unsigned char syscall_trace;	/* count of syscall interceptors */
-	unsigned char memdie;		/* task was selected to be killed */
-	unsigned char pad[2];
-};
-
 struct thread_struct {
 	unsigned long  ksp;		/* kernel stack pointer */
 	unsigned long  usp;		/* user stack pointer */
@@ -79,7 +68,6 @@ struct thread_struct {
 	unsigned long  fp[8*3];
 	unsigned long  fpcntl[3];	/* fp control regs */
 	unsigned char  fpstate[FPSTATESIZE];  /* floating point state */
-	struct task_work work;
 	struct thread_info info;
 };
 
diff --git a/include/asm-m68k/thread_info.h b/include/asm-m68k/thread_info.h
index 4fdbf55..9532ca3 100644
--- a/include/asm-m68k/thread_info.h
+++ b/include/asm-m68k/thread_info.h
@@ -6,12 +6,11 @@
 
 struct thread_info {
 	struct task_struct	*task;		/* main task structure */
+	unsigned long		flags;
 	struct exec_domain	*exec_domain;	/* execution domain */
 	int			preempt_count;	/* 0 => preemptable, <0 => BUG */
 	__u32 cpu; /* should always be 0 on m68k */
 	struct restart_block    restart_block;
-
-	__u8			supervisor_stack[0];
 };
 
 #define PREEMPT_ACTIVE		0x4000000
@@ -49,76 +48,14 @@ struct thread_info {
 
 #define end_of_stack(p) ((unsigned long *)(p)->thread_info + 1)
 
-#define TIF_SYSCALL_TRACE	0	/* syscall trace active */
-#define TIF_DELAYED_TRACE	1	/* single step a syscall */
-#define TIF_NOTIFY_RESUME	2	/* resumption notification requested */
-#define TIF_SIGPENDING		3	/* signal pending */
-#define TIF_NEED_RESCHED	4	/* rescheduling necessary */
-#define TIF_MEMDIE		5
-
-extern int thread_flag_fixme(void);
-
-/*
- * flag set/clear/test wrappers
- * - pass TIF_xxxx constants to these functions
+/* entry.S relies on these definitions!
+ * bits 0-7 are tested at every exception exit
+ * bits 8-15 are also tested at syscall exit
  */
-
-#define __set_tsk_thread_flag(tsk, flag, val) ({	\
-	switch (flag) {					\
-	case TIF_SIGPENDING:				\
-		tsk->thread.work.sigpending = val;	\
-		break;					\
-	case TIF_NEED_RESCHED:				\
-		tsk->thread.work.need_resched = val;	\
-		break;					\
-	case TIF_SYSCALL_TRACE:				\
-		tsk->thread.work.syscall_trace = val;	\
-		break;					\
-	case TIF_MEMDIE:				\
-		tsk->thread.work.memdie = val;		\
-		break;					\
-	default:					\
-		thread_flag_fixme();			\
-	}						\
-})
-
-#define __get_tsk_thread_flag(tsk, flag) ({		\
-	int ___res;					\
-	switch (flag) {					\
-	case TIF_SIGPENDING:				\
-		___res = tsk->thread.work.sigpending;	\
-		break;					\
-	case TIF_NEED_RESCHED:				\
-		___res = tsk->thread.work.need_resched;	\
-		break;					\
-	case TIF_SYSCALL_TRACE:				\
-		___res = tsk->thread.work.syscall_trace;\
-		break;					\
-	case TIF_MEMDIE:				\
-		___res = tsk->thread.work.memdie;\
-		break;					\
-	default:					\
-		___res = thread_flag_fixme();		\
-	}						\
-	___res;						\
-})
-
-#define __get_set_tsk_thread_flag(tsk, flag, val) ({	\
-	int __res = __get_tsk_thread_flag(tsk, flag);	\
-	__set_tsk_thread_flag(tsk, flag, val);		\
-	__res;						\
-})
-
-#define set_tsk_thread_flag(tsk, flag) __set_tsk_thread_flag(tsk, flag, ~0)
-#define clear_tsk_thread_flag(tsk, flag) __set_tsk_thread_flag(tsk, flag, 0)
-#define test_and_set_tsk_thread_flag(tsk, flag) __get_set_tsk_thread_flag(tsk, flag, ~0)
-#define test_tsk_thread_flag(tsk, flag) __get_tsk_thread_flag(tsk, flag)
-
-#define set_thread_flag(flag) set_tsk_thread_flag(current, flag)
-#define clear_thread_flag(flag) clear_tsk_thread_flag(current, flag)
-#define test_thread_flag(flag) test_tsk_thread_flag(current, flag)
-
-#define set_need_resched() set_thread_flag(TIF_NEED_RESCHED)
-#define clear_need_resched() clear_thread_flag(TIF_NEED_RESCHED)
+#define TIF_SIGPENDING		6	/* signal pending */
+#define TIF_NEED_RESCHED	7	/* rescheduling necessary */
+#define TIF_DELAYED_TRACE	14	/* single step a syscall */
+#define TIF_SYSCALL_TRACE	15	/* syscall trace active */
+#define TIF_MEMDIE		16
 
 #endif	/* _ASM_M68K_THREAD_INFO_H */
diff --git a/include/linux/thread_info.h b/include/linux/thread_info.h
index d252f45..1c4eb41 100644
--- a/include/linux/thread_info.h
+++ b/include/linux/thread_info.h
@@ -27,31 +27,6 @@ extern long do_no_restart_syscall(struct restart_block *parm);
  * - pass TIF_xxxx constants to these functions
  */
 
-static inline void set_thread_flag(int flag)
-{
-	set_bit(flag,&current_thread_info()->flags);
-}
-
-static inline void clear_thread_flag(int flag)
-{
-	clear_bit(flag,&current_thread_info()->flags);
-}
-
-static inline int test_and_set_thread_flag(int flag)
-{
-	return test_and_set_bit(flag,&current_thread_info()->flags);
-}
-
-static inline int test_and_clear_thread_flag(int flag)
-{
-	return test_and_clear_bit(flag,&current_thread_info()->flags);
-}
-
-static inline int test_thread_flag(int flag)
-{
-	return test_bit(flag,&current_thread_info()->flags);
-}
-
 static inline void set_ti_thread_flag(struct thread_info *ti, int flag)
 {
 	set_bit(flag,&ti->flags);
@@ -77,15 +52,19 @@ static inline int test_ti_thread_flag(struct thread_info *ti, int flag)
 	return test_bit(flag,&ti->flags);
 }
 
-static inline void set_need_resched(void)
-{
-	set_thread_flag(TIF_NEED_RESCHED);
-}
-
-static inline void clear_need_resched(void)
-{
-	clear_thread_flag(TIF_NEED_RESCHED);
-}
+#define set_thread_flag(flag) \
+	set_ti_thread_flag(current_thread_info(), flag)
+#define clear_thread_flag(flag) \
+	clear_ti_thread_flag(current_thread_info(), flag)
+#define test_and_set_thread_flag(flag) \
+	test_and_set_ti_thread_flag(current_thread_info(), flag)
+#define test_and_clear_thread_flag(flag) \
+	test_and_clear_ti_thread_flag(current_thread_info(), flag)
+#define test_thread_flag(flag) \
+	test_ti_thread_flag(current_thread_info(), flag)
+
+#define set_need_resched()	set_thread_flag(TIF_NEED_RESCHED)
+#define clear_need_resched()	clear_thread_flag(TIF_NEED_RESCHED)
 
 #endif