linux/arch/score/include/asm/processor.h

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#ifndef _ASM_SCORE_PROCESSOR_H
#define _ASM_SCORE_PROCESSOR_H
#include <linux/cpumask.h>
#include <linux/threads.h>
#include <asm/segment.h>
struct task_struct;
/*
* System setup and hardware flags..
*/
extern void (*cpu_wait)(void);
extern unsigned long thread_saved_pc(struct task_struct *tsk);
extern void start_thread(struct pt_regs *regs,
unsigned long pc, unsigned long sp);
extern unsigned long get_wchan(struct task_struct *p);
/*
* Return current * instruction pointer ("program counter").
*/
#define current_text_addr() ({ __label__ _l; _l: &&_l; })
#define cpu_relax() barrier()
locking/core: Introduce cpu_relax_yield() For spinning loops people do often use barrier() or cpu_relax(). For most architectures cpu_relax and barrier are the same, but on some architectures cpu_relax can add some latency. For example on power,sparc64 and arc, cpu_relax can shift the CPU towards other hardware threads in an SMT environment. On s390 cpu_relax does even more, it uses an hypercall to the hypervisor to give up the timeslice. In contrast to the SMT yielding this can result in larger latencies. In some places this latency is unwanted, so another variant "cpu_relax_lowlatency" was introduced. Before this is used in more and more places, lets revert the logic and provide a cpu_relax_yield that can be called in places where yielding is more important than latency. By default this is the same as cpu_relax on all architectures. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.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: Peter Zijlstra <peterz@infradead.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linuxppc-dev@lists.ozlabs.org Cc: virtualization@lists.linux-foundation.org Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1477386195-32736-2-git-send-email-borntraeger@de.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-25 09:03:11 +00:00
#define cpu_relax_yield() cpu_relax()
#define release_thread(thread) do {} while (0)
/*
* User space process size: 2GB. This is hardcoded into a few places,
* so don't change it unless you know what you are doing.
*/
#define TASK_SIZE 0x7fff8000UL
/*
* This decides where the kernel will search for a free chunk of vm
* space during mmap's.
*/
#define TASK_UNMAPPED_BASE ((TASK_SIZE / 3) & ~(PAGE_SIZE))
#ifdef __KERNEL__
#define STACK_TOP TASK_SIZE
#define STACK_TOP_MAX TASK_SIZE
#endif
/*
* If you change thread_struct remember to change the #defines below too!
*/
struct thread_struct {
unsigned long reg0, reg2, reg3;
unsigned long reg12, reg13, reg14, reg15, reg16;
unsigned long reg17, reg18, reg19, reg20, reg21;
unsigned long cp0_psr;
unsigned long cp0_ema; /* Last user fault */
unsigned long cp0_badvaddr; /* Last user fault */
unsigned long cp0_baduaddr; /* Last kernel fault accessing USEG */
unsigned long error_code;
unsigned long trap_no;
unsigned long mflags;
unsigned long reg29;
unsigned long single_step;
unsigned long ss_nextcnt;
unsigned long insn1_type;
unsigned long addr1;
unsigned long insn1;
unsigned long insn2_type;
unsigned long addr2;
unsigned long insn2;
mm_segment_t current_ds;
};
#define INIT_THREAD { \
.reg0 = 0, \
.reg2 = 0, \
.reg3 = 0, \
.reg12 = 0, \
.reg13 = 0, \
.reg14 = 0, \
.reg15 = 0, \
.reg16 = 0, \
.reg17 = 0, \
.reg18 = 0, \
.reg19 = 0, \
.reg20 = 0, \
.reg21 = 0, \
.cp0_psr = 0, \
.error_code = 0, \
.trap_no = 0, \
}
#define kstk_tos(tsk) \
((unsigned long)task_stack_page(tsk) + THREAD_SIZE - 32)
#define task_pt_regs(tsk) ((struct pt_regs *)kstk_tos(tsk) - 1)
#define KSTK_EIP(tsk) (task_pt_regs(tsk)->cp0_epc)
#define KSTK_ESP(tsk) (task_pt_regs(tsk)->regs[29])
#endif /* _ASM_SCORE_PROCESSOR_H */