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>
107 lines
2.9 KiB
C
107 lines
2.9 KiB
C
/* thread_info.h: m68knommu low-level thread information
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* adapted from the i386 and PPC versions by Greg Ungerer (gerg@snapgear.com)
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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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#include <asm/page.h>
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#ifdef __KERNEL__
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#ifndef __ASSEMBLY__
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/*
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* Size of kernel stack for each process. This must be a power of 2...
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*/
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#ifdef CONFIG_4KSTACKS
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#define THREAD_SIZE_ORDER (0)
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#else
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#define THREAD_SIZE_ORDER (1)
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#endif
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/*
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* for asm files, THREAD_SIZE is now generated by asm-offsets.c
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*/
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#define THREAD_SIZE (PAGE_SIZE<<THREAD_SIZE_ORDER)
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/*
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* low level task data.
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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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int cpu; /* cpu we're on */
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int preempt_count; /* 0 => preemptable, <0 => BUG */
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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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#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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.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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static inline struct thread_info *current_thread_info(void)
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{
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struct thread_info *ti;
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__asm__(
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"move.l %%sp, %0 \n\t"
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"and.l %1, %0"
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: "=&d"(ti)
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: "di" (~(THREAD_SIZE-1))
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);
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return ti;
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}
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/* thread information allocation */
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#define alloc_thread_info(tsk) ((struct thread_info *) \
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__get_free_pages(GFP_KERNEL, THREAD_SIZE_ORDER))
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#define free_thread_info(ti) free_pages((unsigned long) (ti), THREAD_SIZE_ORDER)
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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 0x4000000
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/*
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* thread information flag bit numbers
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*/
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#define TIF_SYSCALL_TRACE 0 /* syscall trace active */
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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_POLLING_NRFLAG 4 /* true if poll_idle() is polling
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TIF_NEED_RESCHED */
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#define TIF_MEMDIE 5
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/* as above, but as bit values */
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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_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
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#define _TIF_WORK_MASK 0x0000FFFE /* work to do on interrupt/exception return */
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#endif /* __KERNEL__ */
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#endif /* _ASM_THREAD_INFO_H */
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