dcd497f99a
The preempt_count member of struct thread_info is currently either defined as int, unsigned int or __s32 depending on arch. This patch makes the type of preempt_count an int on all archs. Having preempt_count be an unsigned type prevents the catching of preempt_count < 0 bugs, and using int on some archs and __s32 on others is not exactely "neat" - much nicer when it's just int all over. A previous version of this patch was already ACK'ed by Robert Love, and the only change in this version of the patch compared to the one he ACK'ed is that this one also makes sure the preempt_count member is consistently commented. Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
137 lines
4 KiB
C
137 lines
4 KiB
C
/* thread_info.h: MIPS low-level thread information
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*
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* Copyright (C) 2002 David Howells (dhowells@redhat.com)
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* - Incorporating suggestions made by Linus Torvalds and Dave Miller
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*/
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#ifndef _ASM_THREAD_INFO_H
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#define _ASM_THREAD_INFO_H
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#ifdef __KERNEL__
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#include <linux/config.h>
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#ifndef __ASSEMBLY__
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#include <asm/processor.h>
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/*
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* low level task data that entry.S needs immediate access to
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* - this struct should fit entirely inside of one cache line
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* - this struct shares the supervisor stack pages
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* - if the contents of this structure are changed, the assembly constants
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* must also be changed
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*/
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struct thread_info {
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struct task_struct *task; /* main task structure */
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struct exec_domain *exec_domain; /* execution domain */
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unsigned long flags; /* low level flags */
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__u32 cpu; /* current CPU */
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int preempt_count; /* 0 => preemptable, <0 => BUG */
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mm_segment_t addr_limit; /* thread address space:
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0-0xBFFFFFFF for user-thead
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0-0xFFFFFFFF for kernel-thread
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*/
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struct restart_block restart_block;
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};
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/*
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* macros/functions for gaining access to the thread information structure
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*
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* preempt_count needs to be 1 initially, until the scheduler is functional.
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*/
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#define INIT_THREAD_INFO(tsk) \
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{ \
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.task = &tsk, \
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.exec_domain = &default_exec_domain, \
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.flags = 0, \
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.cpu = 0, \
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.preempt_count = 1, \
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.addr_limit = KERNEL_DS, \
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.restart_block = { \
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.fn = do_no_restart_syscall, \
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}, \
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}
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#define init_thread_info (init_thread_union.thread_info)
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#define init_stack (init_thread_union.stack)
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/* How to get the thread information struct from C. */
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register struct thread_info *__current_thread_info __asm__("$28");
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#define current_thread_info() __current_thread_info
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/* thread information allocation */
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#if defined(CONFIG_PAGE_SIZE_4KB) && defined(CONFIG_MIPS32)
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#define THREAD_SIZE_ORDER (1)
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#endif
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#if defined(CONFIG_PAGE_SIZE_4KB) && defined(CONFIG_MIPS64)
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#define THREAD_SIZE_ORDER (2)
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#endif
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#ifdef CONFIG_PAGE_SIZE_8KB
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#define THREAD_SIZE_ORDER (1)
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#endif
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#ifdef CONFIG_PAGE_SIZE_16KB
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#define THREAD_SIZE_ORDER (0)
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#endif
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#ifdef CONFIG_PAGE_SIZE_64KB
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#define THREAD_SIZE_ORDER (0)
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#endif
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#define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
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#define THREAD_MASK (THREAD_SIZE - 1UL)
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#ifdef CONFIG_DEBUG_STACK_USAGE
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#define alloc_thread_info(tsk) \
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({ \
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struct thread_info *ret; \
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\
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ret = kmalloc(THREAD_SIZE, GFP_KERNEL); \
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if (ret) \
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memset(ret, 0, THREAD_SIZE); \
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ret; \
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})
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#else
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#define alloc_thread_info(tsk) kmalloc(THREAD_SIZE, GFP_KERNEL)
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#endif
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#define free_thread_info(info) kfree(info)
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#define get_thread_info(ti) get_task_struct((ti)->task)
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#define put_thread_info(ti) put_task_struct((ti)->task)
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#endif /* !__ASSEMBLY__ */
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#define PREEMPT_ACTIVE 0x10000000
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/*
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* thread information flags
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* - these are process state flags that various assembly files may need to
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* access
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* - pending work-to-be-done flags are in LSW
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* - other flags in MSW
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*/
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#define TIF_NOTIFY_RESUME 1 /* resumption notification requested */
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#define TIF_SIGPENDING 2 /* signal pending */
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#define TIF_NEED_RESCHED 3 /* rescheduling necessary */
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#define TIF_SYSCALL_AUDIT 4 /* syscall auditing active */
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#define TIF_USEDFPU 16 /* FPU was used by this task this quantum (SMP) */
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#define TIF_POLLING_NRFLAG 17 /* true if poll_idle() is polling TIF_NEED_RESCHED */
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#define TIF_MEMDIE 18
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#define TIF_SYSCALL_TRACE 31 /* syscall trace active */
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#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
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#define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
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#define _TIF_SIGPENDING (1<<TIF_SIGPENDING)
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#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
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#define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT)
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#define _TIF_USEDFPU (1<<TIF_USEDFPU)
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#define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
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#define _TIF_WORK_MASK 0x0000ffef /* work to do on
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interrupt/exception return */
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#define _TIF_ALLWORK_MASK 0x8000ffff /* work to do on any return to
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u-space */
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#endif /* __KERNEL__ */
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#endif /* _ASM_THREAD_INFO_H */
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