linux/include/asm-ia64/thread_info.h
Cliff Wickman 1df57c0c21 [IA64] enable dumps to capture second page of kernel stack
In SLES10 (2.6.16) crash dumping (in my experience, LKCD) is unable to
capture the second page of the 2-page task/stack allocation.
This is particularly troublesome for dump analysis, as the stack traceback
cannot be done.
  (A similar convention is probably needed throughout the kernel to make
   kernel multi-page allocations detectable for dumping)

Multi-page kernel allocations are represented by the single page structure
associated with the first page of the allocation.  The page structures
associated with the other pages are unintialized.

If the dumper is selecting only kernel pages it has no way to identify
any but the first page of the allocation.

The fix is to make the task/stack allocation a compound page.

Signed-off-by: Cliff Wickman <cpw@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-04-27 14:31:16 -07:00

106 lines
4 KiB
C

/*
* Copyright (C) 2002-2003 Hewlett-Packard Co
* David Mosberger-Tang <davidm@hpl.hp.com>
*/
#ifndef _ASM_IA64_THREAD_INFO_H
#define _ASM_IA64_THREAD_INFO_H
#ifndef ASM_OFFSETS_C
#include <asm/asm-offsets.h>
#endif
#include <asm/processor.h>
#include <asm/ptrace.h>
#define PREEMPT_ACTIVE_BIT 30
#define PREEMPT_ACTIVE (1 << PREEMPT_ACTIVE_BIT)
#ifndef __ASSEMBLY__
/*
* On IA-64, we want to keep the task structure and kernel stack together, so they can be
* mapped by a single TLB entry and so they can be addressed by the "current" pointer
* without having to do pointer masking.
*/
struct thread_info {
struct task_struct *task; /* XXX not really needed, except for dup_task_struct() */
struct exec_domain *exec_domain;/* execution domain */
__u32 flags; /* thread_info flags (see TIF_*) */
__u32 cpu; /* current CPU */
__u32 last_cpu; /* Last CPU thread ran on */
mm_segment_t addr_limit; /* user-level address space limit */
int preempt_count; /* 0=premptable, <0=BUG; will also serve as bh-counter */
struct restart_block restart_block;
};
#define THREAD_SIZE KERNEL_STACK_SIZE
#define INIT_THREAD_INFO(tsk) \
{ \
.task = &tsk, \
.exec_domain = &default_exec_domain, \
.flags = 0, \
.cpu = 0, \
.addr_limit = KERNEL_DS, \
.preempt_count = 0, \
.restart_block = { \
.fn = do_no_restart_syscall, \
}, \
}
#ifndef ASM_OFFSETS_C
/* how to get the thread information struct from C */
#define current_thread_info() ((struct thread_info *) ((char *) current + IA64_TASK_SIZE))
#define alloc_thread_info(tsk) ((struct thread_info *) ((char *) (tsk) + IA64_TASK_SIZE))
#define task_thread_info(tsk) ((struct thread_info *) ((char *) (tsk) + IA64_TASK_SIZE))
#else
#define current_thread_info() ((struct thread_info *) 0)
#define alloc_thread_info(tsk) ((struct thread_info *) 0)
#define task_thread_info(tsk) ((struct thread_info *) 0)
#endif
#define free_thread_info(ti) /* nothing */
#define task_stack_page(tsk) ((void *)(tsk))
#define __HAVE_THREAD_FUNCTIONS
#define setup_thread_stack(p, org) \
*task_thread_info(p) = *task_thread_info(org); \
task_thread_info(p)->task = (p);
#define end_of_stack(p) (unsigned long *)((void *)(p) + IA64_RBS_OFFSET)
#define __HAVE_ARCH_TASK_STRUCT_ALLOCATOR
#define alloc_task_struct() ((task_t *)__get_free_pages(GFP_KERNEL | __GFP_COMP, KERNEL_STACK_SIZE_ORDER))
#define free_task_struct(tsk) free_pages((unsigned long) (tsk), KERNEL_STACK_SIZE_ORDER)
#endif /* !__ASSEMBLY */
/*
* thread information flags
* - these are process state flags that various assembly files may need to access
* - pending work-to-be-done flags are in least-significant 16 bits, other flags
* in top 16 bits
*/
#define TIF_NOTIFY_RESUME 0 /* resumption notification requested */
#define TIF_SIGPENDING 1 /* signal pending */
#define TIF_NEED_RESCHED 2 /* rescheduling necessary */
#define TIF_SYSCALL_TRACE 3 /* syscall trace active */
#define TIF_SYSCALL_AUDIT 4 /* syscall auditing active */
#define TIF_POLLING_NRFLAG 16 /* true if poll_idle() is polling TIF_NEED_RESCHED */
#define TIF_MEMDIE 17
#define TIF_MCA_INIT 18 /* this task is processing MCA or INIT */
#define TIF_DB_DISABLED 19 /* debug trap disabled for fsyscall */
#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
#define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT)
#define _TIF_SYSCALL_TRACEAUDIT (_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
#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_MCA_INIT (1 << TIF_MCA_INIT)
#define _TIF_DB_DISABLED (1 << TIF_DB_DISABLED)
/* "work to do on user-return" bits */
#define TIF_ALLWORK_MASK (_TIF_NOTIFY_RESUME|_TIF_SIGPENDING|_TIF_NEED_RESCHED|_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
/* like TIF_ALLWORK_BITS but sans TIF_SYSCALL_TRACE or TIF_SYSCALL_AUDIT */
#define TIF_WORK_MASK (TIF_ALLWORK_MASK&~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT))
#endif /* _ASM_IA64_THREAD_INFO_H */