mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 19:00:25 +00:00
![David Howells](/assets/img/avatar_default.png)
Construct the init thread stack in the linker script rather than doing it by means of a union so that ia64's init_task.c can be got rid of. The following symbols are then made available from INIT_TASK_DATA() linker script macro: init_thread_union init_stack INIT_TASK_DATA() also expands the region to THREAD_SIZE to accommodate the size of the init stack. init_thread_union is given its own section so that it can be placed into the stack space in the right order. I'm assuming that the ia64 ordering is correct and that the task_struct is first and the thread_info second. Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Tony Luck <tony.luck@intel.com> Tested-by: Will Deacon <will.deacon@arm.com> (arm64) Tested-by: Palmer Dabbelt <palmer@sifive.com> Acked-by: Thomas Gleixner <tglx@linutronix.de>
141 lines
4.1 KiB
C
141 lines
4.1 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/* thread_info.h: Meta low-level thread information
|
|
*
|
|
* Copyright (C) 2002 David Howells (dhowells@redhat.com)
|
|
* - Incorporating suggestions made by Linus Torvalds and Dave Miller
|
|
*
|
|
* Meta port by Imagination Technologies
|
|
*/
|
|
|
|
#ifndef _ASM_THREAD_INFO_H
|
|
#define _ASM_THREAD_INFO_H
|
|
|
|
#include <linux/compiler.h>
|
|
#include <asm/page.h>
|
|
|
|
#ifndef __ASSEMBLY__
|
|
#include <asm/processor.h>
|
|
#endif
|
|
|
|
/*
|
|
* low level task data that entry.S needs immediate access to
|
|
* - this struct should fit entirely inside of one cache line
|
|
* - this struct shares the supervisor stack pages
|
|
* - if the contents of this structure are changed, the assembly constants must
|
|
* also be changed
|
|
*/
|
|
#ifndef __ASSEMBLY__
|
|
|
|
/* This must be 8 byte aligned so we can ensure stack alignment. */
|
|
struct thread_info {
|
|
struct task_struct *task; /* main task structure */
|
|
unsigned long flags; /* low level flags */
|
|
unsigned long status; /* thread-synchronous flags */
|
|
u32 cpu; /* current CPU */
|
|
int preempt_count; /* 0 => preemptable, <0 => BUG */
|
|
|
|
mm_segment_t addr_limit; /* thread address space */
|
|
|
|
u8 supervisor_stack[0] __aligned(8);
|
|
};
|
|
|
|
#else /* !__ASSEMBLY__ */
|
|
|
|
#include <generated/asm-offsets.h>
|
|
|
|
#endif
|
|
|
|
#ifdef CONFIG_4KSTACKS
|
|
#define THREAD_SHIFT 12
|
|
#else
|
|
#define THREAD_SHIFT 13
|
|
#endif
|
|
|
|
#if THREAD_SHIFT >= PAGE_SHIFT
|
|
#define THREAD_SIZE_ORDER (THREAD_SHIFT - PAGE_SHIFT)
|
|
#else
|
|
#define THREAD_SIZE_ORDER 0
|
|
#endif
|
|
|
|
#define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
|
|
|
|
#define STACK_WARN (THREAD_SIZE/8)
|
|
/*
|
|
* macros/functions for gaining access to the thread information structure
|
|
*/
|
|
#ifndef __ASSEMBLY__
|
|
|
|
#define INIT_THREAD_INFO(tsk) \
|
|
{ \
|
|
.task = &tsk, \
|
|
.flags = 0, \
|
|
.cpu = 0, \
|
|
.preempt_count = INIT_PREEMPT_COUNT, \
|
|
.addr_limit = KERNEL_DS, \
|
|
}
|
|
|
|
/* how to get the current stack pointer from C */
|
|
register unsigned long current_stack_pointer asm("A0StP") __used;
|
|
|
|
/* how to get the thread information struct from C */
|
|
static inline struct thread_info *current_thread_info(void)
|
|
{
|
|
return (struct thread_info *)(current_stack_pointer &
|
|
~(THREAD_SIZE - 1));
|
|
}
|
|
|
|
#define __HAVE_ARCH_KSTACK_END
|
|
static inline int kstack_end(void *addr)
|
|
{
|
|
return addr == (void *) (((unsigned long) addr & ~(THREAD_SIZE - 1))
|
|
+ sizeof(struct thread_info));
|
|
}
|
|
|
|
#endif
|
|
|
|
/*
|
|
* thread information flags
|
|
* - these are process state flags that various assembly files may need to
|
|
* access
|
|
* - pending work-to-be-done flags are in LSW
|
|
* - other flags in MSW
|
|
*/
|
|
#define TIF_SYSCALL_TRACE 0 /* syscall trace active */
|
|
#define TIF_SIGPENDING 1 /* signal pending */
|
|
#define TIF_NEED_RESCHED 2 /* rescheduling necessary */
|
|
#define TIF_SINGLESTEP 3 /* restore singlestep on return to user
|
|
mode */
|
|
#define TIF_SYSCALL_AUDIT 4 /* syscall auditing active */
|
|
#define TIF_SECCOMP 5 /* secure computing */
|
|
#define TIF_RESTORE_SIGMASK 6 /* restore signal mask in do_signal() */
|
|
#define TIF_NOTIFY_RESUME 7 /* callback before returning to user */
|
|
#define TIF_MEMDIE 8 /* is terminating due to OOM killer */
|
|
#define TIF_SYSCALL_TRACEPOINT 9 /* syscall tracepoint instrumentation */
|
|
|
|
|
|
#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
|
|
#define _TIF_SIGPENDING (1<<TIF_SIGPENDING)
|
|
#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
|
|
#define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP)
|
|
#define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT)
|
|
#define _TIF_SECCOMP (1<<TIF_SECCOMP)
|
|
#define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
|
|
#define _TIF_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK)
|
|
#define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT)
|
|
|
|
/* work to do in syscall trace */
|
|
#define _TIF_WORK_SYSCALL_MASK (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP | \
|
|
_TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \
|
|
_TIF_SYSCALL_TRACEPOINT)
|
|
|
|
/* work to do on any return to u-space */
|
|
#define _TIF_ALLWORK_MASK (_TIF_SYSCALL_TRACE | _TIF_SIGPENDING | \
|
|
_TIF_NEED_RESCHED | _TIF_SYSCALL_AUDIT | \
|
|
_TIF_SINGLESTEP | _TIF_RESTORE_SIGMASK | \
|
|
_TIF_NOTIFY_RESUME)
|
|
|
|
/* work to do on interrupt/exception return */
|
|
#define _TIF_WORK_MASK (_TIF_ALLWORK_MASK & ~(_TIF_SYSCALL_TRACE | \
|
|
_TIF_SYSCALL_AUDIT | _TIF_SINGLESTEP))
|
|
|
|
#endif /* _ASM_THREAD_INFO_H */
|