alistair23-linux/include/asm-powerpc/thread_info.h
Benjamin Herrenschmidt 3c726f8dee [PATCH] ppc64: support 64k pages
Adds a new CONFIG_PPC_64K_PAGES which, when enabled, changes the kernel
base page size to 64K.  The resulting kernel still boots on any
hardware.  On current machines with 4K pages support only, the kernel
will maintain 16 "subpages" for each 64K page transparently.

Note that while real 64K capable HW has been tested, the current patch
will not enable it yet as such hardware is not released yet, and I'm
still verifying with the firmware architects the proper to get the
information from the newer hypervisors.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-06 16:56:47 -08:00

147 lines
4.2 KiB
C

/* thread_info.h: PowerPC low-level thread information
* adapted from the i386 version by Paul Mackerras
*
* Copyright (C) 2002 David Howells (dhowells@redhat.com)
* - Incorporating suggestions made by Linus Torvalds and Dave Miller
*/
#ifndef _ASM_POWERPC_THREAD_INFO_H
#define _ASM_POWERPC_THREAD_INFO_H
#ifdef __KERNEL__
/* We have 8k stacks on ppc32 and 16k on ppc64 */
#ifdef CONFIG_PPC64
#define THREAD_SHIFT 14
#else
#define THREAD_SHIFT 13
#endif
#define THREAD_SIZE (1 << THREAD_SHIFT)
#ifndef __ASSEMBLY__
#include <linux/config.h>
#include <linux/cache.h>
#include <asm/processor.h>
#include <asm/page.h>
#include <linux/stringify.h>
/*
* low level task data.
*/
struct thread_info {
struct task_struct *task; /* main task structure */
struct exec_domain *exec_domain; /* execution domain */
int cpu; /* cpu we're on */
int preempt_count; /* 0 => preemptable,
<0 => BUG */
struct restart_block restart_block;
/* set by force_successful_syscall_return */
unsigned char syscall_noerror;
/* low level flags - has atomic operations done on it */
unsigned long flags ____cacheline_aligned_in_smp;
};
/*
* macros/functions for gaining access to the thread information structure
*
* preempt_count needs to be 1 initially, until the scheduler is functional.
*/
#define INIT_THREAD_INFO(tsk) \
{ \
.task = &tsk, \
.exec_domain = &default_exec_domain, \
.cpu = 0, \
.preempt_count = 1, \
.restart_block = { \
.fn = do_no_restart_syscall, \
}, \
.flags = 0, \
}
#define init_thread_info (init_thread_union.thread_info)
#define init_stack (init_thread_union.stack)
/* thread information allocation */
#if THREAD_SHIFT >= PAGE_SHIFT
#define THREAD_ORDER (THREAD_SHIFT - PAGE_SHIFT)
#ifdef CONFIG_DEBUG_STACK_USAGE
#define alloc_thread_info(tsk) \
((struct thread_info *)__get_free_pages(GFP_KERNEL | \
__GFP_ZERO, THREAD_ORDER))
#else
#define alloc_thread_info(tsk) \
((struct thread_info *)__get_free_pages(GFP_KERNEL, THREAD_ORDER))
#endif
#define free_thread_info(ti) free_pages((unsigned long)ti, THREAD_ORDER)
#else /* THREAD_SHIFT < PAGE_SHIFT */
#ifdef CONFIG_DEBUG_STACK_USAGE
#define alloc_thread_info(tsk) kzalloc(THREAD_SIZE, GFP_KERNEL)
#else
#define alloc_thread_info(tsk) kmalloc(THREAD_SIZE, GFP_KERNEL)
#endif
#define free_thread_info(ti) kfree(ti)
#endif /* THREAD_SHIFT < PAGE_SHIFT */
#define get_thread_info(ti) get_task_struct((ti)->task)
#define put_thread_info(ti) put_task_struct((ti)->task)
/* how to get the thread information struct from C */
static inline struct thread_info *current_thread_info(void)
{
register unsigned long sp asm("r1");
/* gcc4, at least, is smart enough to turn this into a single
* rlwinm for ppc32 and clrrdi for ppc64 */
return (struct thread_info *)(sp & ~(THREAD_SIZE-1));
}
#endif /* __ASSEMBLY__ */
#define PREEMPT_ACTIVE 0x10000000
/*
* thread information flag bit numbers
*/
#define TIF_SYSCALL_TRACE 0 /* syscall trace active */
#define TIF_NOTIFY_RESUME 1 /* resumption notification requested */
#define TIF_SIGPENDING 2 /* signal pending */
#define TIF_NEED_RESCHED 3 /* rescheduling necessary */
#define TIF_POLLING_NRFLAG 4 /* true if poll_idle() is polling
TIF_NEED_RESCHED */
#define TIF_32BIT 5 /* 32 bit binary */
/* #define SPARE 6 */
#define TIF_ABI_PENDING 7 /* 32/64 bit switch needed */
#define TIF_SYSCALL_AUDIT 8 /* syscall auditing active */
#define TIF_SINGLESTEP 9 /* singlestepping active */
#define TIF_MEMDIE 10
#define TIF_SECCOMP 11 /* secure computing */
/* as above, but as bit values */
#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
#define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
#define _TIF_SIGPENDING (1<<TIF_SIGPENDING)
#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
#define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
#define _TIF_32BIT (1<<TIF_32BIT)
/* #define _SPARE (1<<SPARE) */
#define _TIF_ABI_PENDING (1<<TIF_ABI_PENDING)
#define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT)
#define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP)
#define _TIF_SECCOMP (1<<TIF_SECCOMP)
#define _TIF_SYSCALL_T_OR_A (_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SECCOMP)
#define _TIF_USER_WORK_MASK (_TIF_NOTIFY_RESUME | _TIF_SIGPENDING | \
_TIF_NEED_RESCHED)
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_THREAD_INFO_H */