locking/core: Provide common cpu_relax_yield() definition

No need to duplicate the same define everywhere. Since
the only user is stop-machine and the only provider is
s390, we can use a default implementation of cpu_relax_yield()
in sched.h.

Suggested-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: kvm@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-s390 <linux-s390@vger.kernel.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: sparclinux@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1479298985-191589-1-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/alpha/include/asm/processor.h

@@ -58,7 +58,6 @@ unsigned long get_wchan(struct task_struct *p);
   ((tsk) == current ? rdusp() : task_thread_info(tsk)->pcb.usp)
 
 #define cpu_relax()	barrier()
-#define cpu_relax_yield() cpu_relax()
 
 #define ARCH_HAS_PREFETCH
 #define ARCH_HAS_PREFETCHW

arch/arc/include/asm/processor.h

@@ -60,15 +60,12 @@ struct task_struct;
 #ifndef CONFIG_EZNPS_MTM_EXT
 
 #define cpu_relax()		barrier()
-#define cpu_relax_yield()	cpu_relax()
 
 #else
 
 #define cpu_relax()     \
 	__asm__ __volatile__ (".word %0" : : "i"(CTOP_INST_SCHD_RW) : "memory")
 
-#define cpu_relax_yield()	cpu_relax()
-
 #endif
 
 #define copy_segments(tsk, mm)      do { } while (0)

arch/arm/include/asm/processor.h

@@ -82,8 +82,6 @@ unsigned long get_wchan(struct task_struct *p);
 #define cpu_relax()			barrier()
 #endif
 
-#define cpu_relax_yield()  	              cpu_relax()
-
 #define task_pt_regs(p) \
 	((struct pt_regs *)(THREAD_START_SP + task_stack_page(p)) - 1)
 

arch/arm64/include/asm/processor.h

@@ -149,8 +149,6 @@ static inline void cpu_relax(void)
 	asm volatile("yield" ::: "memory");
 }
 
-#define cpu_relax_yield()                     cpu_relax()
-
 /* Thread switching */
 extern struct task_struct *cpu_switch_to(struct task_struct *prev,
 					 struct task_struct *next);

arch/avr32/include/asm/processor.h

@@ -92,7 +92,6 @@ extern struct avr32_cpuinfo boot_cpu_data;
 #define TASK_UNMAPPED_BASE	(PAGE_ALIGN(TASK_SIZE / 3))
 
 #define cpu_relax()		barrier()
-#define cpu_relax_yield()	cpu_relax()
 #define cpu_sync_pipeline()	asm volatile("sub pc, -2" : : : "memory")
 
 struct cpu_context {

arch/blackfin/include/asm/processor.h

@@ -92,7 +92,6 @@ unsigned long get_wchan(struct task_struct *p);
 #define	KSTK_ESP(tsk)	((tsk) == current ? rdusp() : (tsk)->thread.usp)
 
 #define cpu_relax()    	smp_mb()
-#define cpu_relax_yield()      cpu_relax()
 
 /* Get the Silicon Revision of the chip */
 static inline uint32_t __pure bfin_revid(void)

arch/c6x/include/asm/processor.h

@@ -121,7 +121,6 @@ extern unsigned long get_wchan(struct task_struct *p);
 #define KSTK_ESP(task)	(task_pt_regs(task)->sp)
 
 #define cpu_relax()		do { } while (0)
-#define cpu_relax_yield()             cpu_relax()
 
 extern const struct seq_operations cpuinfo_op;
 

arch/cris/include/asm/processor.h

@@ -63,7 +63,6 @@ static inline void release_thread(struct task_struct *dead_task)
 #define init_stack      (init_thread_union.stack)
 
 #define cpu_relax()     barrier()
-#define cpu_relax_yield() cpu_relax()
 
 void default_idle(void);
 

arch/frv/include/asm/processor.h

@@ -107,7 +107,6 @@ unsigned long get_wchan(struct task_struct *p);
 #define	KSTK_ESP(tsk)	((tsk)->thread.frame0->sp)
 
 #define cpu_relax() barrier()
-#define cpu_relax_yield() cpu_relax()
 
 /* data cache prefetch */
 #define ARCH_HAS_PREFETCH

arch/h8300/include/asm/processor.h

@@ -127,7 +127,6 @@ unsigned long get_wchan(struct task_struct *p);
 #define	KSTK_ESP(tsk)	((tsk) == current ? rdusp() : (tsk)->thread.usp)
 
 #define cpu_relax()    barrier()
-#define cpu_relax_yield() cpu_relax()
 
 #define HARD_RESET_NOW() ({		\
 	local_irq_disable();		\

arch/hexagon/include/asm/processor.h

@@ -56,7 +56,6 @@ struct thread_struct {
 }
 
 #define cpu_relax() __vmyield()
-#define cpu_relax_yield() cpu_relax()
 
 /*
  * Decides where the kernel will search for a free chunk of vm space during

arch/ia64/include/asm/processor.h

@@ -547,7 +547,6 @@ ia64_eoi (void)
 }
 
 #define cpu_relax()	ia64_hint(ia64_hint_pause)
-#define cpu_relax_yield() cpu_relax()
 
 static inline int
 ia64_get_irr(unsigned int vector)

arch/m32r/include/asm/processor.h

@@ -133,6 +133,5 @@ unsigned long get_wchan(struct task_struct *p);
 #define KSTK_ESP(tsk)  ((tsk)->thread.sp)
 
 #define cpu_relax()	barrier()
-#define cpu_relax_yield() cpu_relax()
 
 #endif /* _ASM_M32R_PROCESSOR_H */

arch/m68k/include/asm/processor.h

@@ -156,6 +156,5 @@ unsigned long get_wchan(struct task_struct *p);
 #define task_pt_regs(tsk)	((struct pt_regs *) ((tsk)->thread.esp0))
 
 #define cpu_relax()	barrier()
-#define cpu_relax_yield() cpu_relax()
 
 #endif

arch/metag/include/asm/processor.h

@@ -152,7 +152,6 @@ unsigned long get_wchan(struct task_struct *p);
 #define user_stack_pointer(regs)        ((regs)->ctx.AX[0].U0)
 
 #define cpu_relax()     barrier()
-#define cpu_relax_yield() cpu_relax()
 
 extern void setup_priv(void);
 

arch/microblaze/include/asm/processor.h

@@ -22,7 +22,6 @@
 extern const struct seq_operations cpuinfo_op;
 
 # define cpu_relax()		barrier()
-# define cpu_relax_yield() cpu_relax()
 
 #define task_pt_regs(tsk) \
 		(((struct pt_regs *)(THREAD_SIZE + task_stack_page(tsk))) - 1)

arch/mips/include/asm/processor.h

@@ -389,7 +389,6 @@ unsigned long get_wchan(struct task_struct *p);
 #define KSTK_STATUS(tsk) (task_pt_regs(tsk)->cp0_status)
 
 #define cpu_relax()	barrier()
-#define cpu_relax_yield() cpu_relax()
 
 /*
  * Return_address is a replacement for __builtin_return_address(count)

arch/mn10300/include/asm/processor.h

@@ -69,7 +69,6 @@ extern void print_cpu_info(struct mn10300_cpuinfo *);
 extern void dodgy_tsc(void);
 
 #define cpu_relax() barrier()
-#define cpu_relax_yield() cpu_relax()
 
 /*
  * User space process size: 1.75GB (default).

arch/nios2/include/asm/processor.h

@@ -88,7 +88,6 @@ extern unsigned long get_wchan(struct task_struct *p);
 #define KSTK_ESP(tsk)	((tsk)->thread.kregs->sp)
 
 #define cpu_relax()	barrier()
-#define cpu_relax_yield() cpu_relax()
 
 #endif /* __ASSEMBLY__ */
 

arch/openrisc/include/asm/processor.h

@@ -92,7 +92,6 @@ extern unsigned long thread_saved_pc(struct task_struct *t);
 #define init_stack      (init_thread_union.stack)
 
 #define cpu_relax()     barrier()
-#define cpu_relax_yield() cpu_relax()
 
 #endif /* __ASSEMBLY__ */
 #endif /* __ASM_OPENRISC_PROCESSOR_H */

arch/parisc/include/asm/processor.h

@@ -309,7 +309,6 @@ extern unsigned long get_wchan(struct task_struct *p);
 #define KSTK_ESP(tsk)	((tsk)->thread.regs.gr[30])
 
 #define cpu_relax()	barrier()
-#define cpu_relax_yield() cpu_relax()
 
 /*
  * parisc_requires_coherency() is used to identify the combined VIPT/PIPT

arch/powerpc/include/asm/processor.h

@@ -404,8 +404,6 @@ static inline unsigned long __pack_fe01(unsigned int fpmode)
 #define cpu_relax()	barrier()
 #endif
 
-#define cpu_relax_yield() cpu_relax()
-
 /* Check that a certain kernel stack pointer is valid in task_struct p */
 int validate_sp(unsigned long sp, struct task_struct *p,
                        unsigned long nbytes);

arch/s390/include/asm/processor.h

@@ -234,6 +234,7 @@ static inline unsigned short stap(void)
 /*
  * Give up the time slice of the virtual PU.
  */
+#define cpu_relax_yield cpu_relax_yield
 void cpu_relax_yield(void);
 
 #define cpu_relax() barrier()

arch/score/include/asm/processor.h

@@ -24,7 +24,6 @@ extern unsigned long get_wchan(struct task_struct *p);
 #define current_text_addr() ({ __label__ _l; _l: &&_l; })
 
 #define cpu_relax()		barrier()
-#define cpu_relax_yield()	cpu_relax()
 #define release_thread(thread)	do {} while (0)
 
 /*

arch/sh/include/asm/processor.h

@@ -97,7 +97,6 @@ extern struct sh_cpuinfo cpu_data[];
 
 #define cpu_sleep()	__asm__ __volatile__ ("sleep" : : : "memory")
 #define cpu_relax()	barrier()
-#define cpu_relax_yield() cpu_relax()
 
 void default_idle(void);
 void stop_this_cpu(void *);

arch/sparc/include/asm/processor_32.h

@@ -119,7 +119,6 @@ extern struct task_struct *last_task_used_math;
 int do_mathemu(struct pt_regs *regs, struct task_struct *fpt);
 
 #define cpu_relax()	barrier()
-#define cpu_relax_yield() cpu_relax()
 
 extern void (*sparc_idle)(void);
 

arch/sparc/include/asm/processor_64.h

@@ -216,7 +216,6 @@ unsigned long get_wchan(struct task_struct *task);
 				     "nop\n\t"				\
 				     ".previous"			\
 				     ::: "memory")
-#define cpu_relax_yield() cpu_relax()
 
 /* Prefetch support.  This is tuned for UltraSPARC-III and later.
  * UltraSPARC-I will treat these as nops, and UltraSPARC-II has

arch/tile/include/asm/processor.h

@@ -264,8 +264,6 @@ static inline void cpu_relax(void)
 	barrier();
 }
 
-#define cpu_relax_yield() cpu_relax()
-
 /* Info on this processor (see fs/proc/cpuinfo.c) */
 struct seq_operations;
 extern const struct seq_operations cpuinfo_op;

arch/unicore32/include/asm/processor.h

@@ -71,7 +71,6 @@ extern void release_thread(struct task_struct *);
 unsigned long get_wchan(struct task_struct *p);
 
 #define cpu_relax()			barrier()
-#define cpu_relax_yield()		cpu_relax()
 
 #define task_pt_regs(p) \
 	((struct pt_regs *)(THREAD_START_SP + task_stack_page(p)) - 1)

arch/x86/include/asm/processor.h

@@ -588,8 +588,6 @@ static __always_inline void cpu_relax(void)
 	rep_nop();
 }
 
-#define cpu_relax_yield() cpu_relax()
-
 /* Stop speculative execution and prefetching of modified code. */
 static inline void sync_core(void)
 {

arch/x86/um/asm/processor.h

@@ -26,7 +26,6 @@ static inline void rep_nop(void)
 }
 
 #define cpu_relax()		rep_nop()
-#define cpu_relax_yield()	cpu_relax()
 
 #define task_pt_regs(t) (&(t)->thread.regs)
 

arch/xtensa/include/asm/processor.h

@@ -206,7 +206,6 @@ extern unsigned long get_wchan(struct task_struct *p);
 #define KSTK_ESP(tsk)		(task_pt_regs(tsk)->areg[1])
 
 #define cpu_relax()  barrier()
-#define cpu_relax_yield() cpu_relax()
 
 /* Special register access. */
 

include/linux/sched.h

@@ -2444,6 +2444,10 @@ static inline void calc_load_enter_idle(void) { }
 static inline void calc_load_exit_idle(void) { }
 #endif /* CONFIG_NO_HZ_COMMON */
 
+#ifndef cpu_relax_yield
+#define cpu_relax_yield() cpu_relax()
+#endif
+
 /*
  * Do not use outside of architecture code which knows its limitations.
  *