arch/sh/include/asm/thread_info.h

Source file repositories/reference/linux-study-clean/arch/sh/include/asm/thread_info.h

File Facts

System
Linux kernel
Corpus path
arch/sh/include/asm/thread_info.h
Extension
.h
Size
5077 bytes
Lines
169
Domain
Architecture Layer
Bucket
arch/sh
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

struct thread_info {
	struct task_struct	*task;		/* main task structure */
	unsigned long		flags;		/* low level flags */
	__u32			status;		/* thread synchronous flags */
	__u32			cpu;
	int			preempt_count; /* 0 => preemptable, <0 => BUG */
	unsigned long		previous_sp;	/* sp of previous stack in case
						   of nested IRQ stacks */
	__u8			supervisor_stack[];
};

#endif

#if defined(CONFIG_4KSTACKS)
#define THREAD_SHIFT	12
#else
#define THREAD_SHIFT	13
#endif

#define THREAD_SIZE	(1 << THREAD_SHIFT)
#define STACK_WARN	(THREAD_SIZE >> 3)

/*
 * macros/functions for gaining access to the thread information structure
 */
#ifndef __ASSEMBLER__
#define INIT_THREAD_INFO(tsk)			\
{						\
	.task		= &tsk,			\
	.flags		= 0,			\
	.status		= 0,			\
	.cpu		= 0,			\
	.preempt_count	= INIT_PREEMPT_COUNT,	\
}

/* how to get the current stack pointer from C */
register unsigned long current_stack_pointer asm("r15") __used;

/* how to get the thread information struct from C */
static inline struct thread_info *current_thread_info(void)
{
	struct thread_info *ti;
#if defined(CONFIG_CPU_HAS_SR_RB)
	__asm__ __volatile__ ("stc	r7_bank, %0" : "=r" (ti));
#else
	unsigned long __dummy;

	__asm__ __volatile__ (
		"mov	r15, %0\n\t"
		"and	%1, %0\n\t"
		: "=&r" (ti), "=r" (__dummy)
		: "1" (~(THREAD_SIZE - 1))
		: "memory");
#endif

	return ti;
}

#define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)

extern void init_thread_xstate(void);

#endif /* __ASSEMBLER__ */

/*
 * Thread information flags
 *
 * - Limited to 24 bits, upper byte used for fault code encoding.
 *
 * - _TIF_ALLWORK_MASK and _TIF_WORK_MASK need to fit within 2 bytes, or
 *   we blow the tst immediate size constraints and need to fix up
 *   arch/sh/kernel/entry-common.S.
 */
#define TIF_SYSCALL_TRACE	0	/* syscall trace active */
#define TIF_SIGPENDING		1	/* signal pending */
#define TIF_NEED_RESCHED	2	/* rescheduling necessary */
#define TIF_NOTIFY_SIGNAL	3	/* signal notifications exist */
#define TIF_SINGLESTEP		4	/* singlestepping active */
#define TIF_SYSCALL_AUDIT	5	/* syscall auditing active */
#define TIF_SECCOMP		6	/* secure computing */
#define TIF_NOTIFY_RESUME	7	/* callback before returning to user */
#define TIF_SYSCALL_TRACEPOINT	8	/* for ftrace syscall instrumentation */
#define TIF_POLLING_NRFLAG	17	/* true if poll_idle() is polling TIF_NEED_RESCHED */
#define TIF_MEMDIE		18	/* is terminating due to OOM killer */

#define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
#define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
#define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
#define _TIF_NOTIFY_SIGNAL	(1 << TIF_NOTIFY_SIGNAL)
#define _TIF_SINGLESTEP		(1 << TIF_SINGLESTEP)

Annotation

Implementation Notes