linux/include/asm-xtensa/thread_info.h
Matt Helsley 83224b0837 container freezer: add TIF_FREEZE flag to all architectures
This patch series introduces a cgroup subsystem that utilizes the swsusp
freezer to freeze a group of tasks.  It's immediately useful for batch job
management scripts.  It should also be useful in the future for
implementing container checkpoint/restart.

The freezer subsystem in the container filesystem defines a cgroup file
named freezer.state.  Reading freezer.state will return the current state
of the cgroup.  Writing "FROZEN" to the state file will freeze all tasks
in the cgroup.  Subsequently writing "RUNNING" will unfreeze the tasks in
the cgroup.

* Examples of usage :

   # mkdir /containers/freezer
   # mount -t cgroup -ofreezer freezer  /containers
   # mkdir /containers/0
   # echo $some_pid > /containers/0/tasks

to get status of the freezer subsystem :

   # cat /containers/0/freezer.state
   RUNNING

to freeze all tasks in the container :

   # echo FROZEN > /containers/0/freezer.state
   # cat /containers/0/freezer.state
   FREEZING
   # cat /containers/0/freezer.state
   FROZEN

to unfreeze all tasks in the container :

   # echo RUNNING > /containers/0/freezer.state
   # cat /containers/0/freezer.state
   RUNNING

This patch:

The first step in making the refrigerator() available to all
architectures, even for those without power management.

The purpose of such a change is to be able to use the refrigerator() in a
new control group subsystem which will implement a control group freezer.

[akpm@linux-foundation.org: fix sparc]
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Matt Helsley <matthltc@us.ibm.com>
Acked-by: Pavel Machek <pavel@suse.cz>
Acked-by: Serge E. Hallyn <serue@us.ibm.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Nigel Cunningham <nigel@tuxonice.net>
Tested-by: Matt Helsley <matthltc@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 08:52:33 -07:00

165 lines
4.4 KiB
C

/*
* include/asm-xtensa/thread_info.h
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2001 - 2005 Tensilica Inc.
*/
#ifndef _XTENSA_THREAD_INFO_H
#define _XTENSA_THREAD_INFO_H
#ifdef __KERNEL__
#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__
#if XTENSA_HAVE_COPROCESSORS
typedef struct xtregs_coprocessor {
xtregs_cp0_t cp0;
xtregs_cp1_t cp1;
xtregs_cp2_t cp2;
xtregs_cp3_t cp3;
xtregs_cp4_t cp4;
xtregs_cp5_t cp5;
xtregs_cp6_t cp6;
xtregs_cp7_t cp7;
} xtregs_coprocessor_t;
#endif
struct thread_info {
struct task_struct *task; /* main task structure */
struct exec_domain *exec_domain; /* execution domain */
unsigned long flags; /* low level flags */
unsigned long status; /* thread-synchronous flags */
__u32 cpu; /* current CPU */
__s32 preempt_count; /* 0 => preemptable,< 0 => BUG*/
mm_segment_t addr_limit; /* thread address space */
struct restart_block restart_block;
unsigned long cpenable;
/* Allocate storage for extra user states and coprocessor states. */
#if XTENSA_HAVE_COPROCESSORS
xtregs_coprocessor_t xtregs_cp;
#endif
xtregs_user_t xtregs_user;
};
#else /* !__ASSEMBLY__ */
/* offsets into the thread_info struct for assembly code access */
#define TI_TASK 0x00000000
#define TI_EXEC_DOMAIN 0x00000004
#define TI_FLAGS 0x00000008
#define TI_STATUS 0x0000000C
#define TI_CPU 0x00000010
#define TI_PRE_COUNT 0x00000014
#define TI_ADDR_LIMIT 0x00000018
#define TI_RESTART_BLOCK 0x000001C
#endif
#define PREEMPT_ACTIVE 0x10000000
/*
* macros/functions for gaining access to the thread information structure
*
* preempt_count needs to be 1 initially, until the scheduler is functional.
*/
#ifndef __ASSEMBLY__
#define INIT_THREAD_INFO(tsk) \
{ \
.task = &tsk, \
.exec_domain = &default_exec_domain, \
.flags = 0, \
.cpu = 0, \
.preempt_count = 1, \
.addr_limit = KERNEL_DS, \
.restart_block = { \
.fn = do_no_restart_syscall, \
}, \
}
#define init_thread_info (init_thread_union.thread_info)
#define init_stack (init_thread_union.stack)
/* how to get the thread information struct from C */
static inline struct thread_info *current_thread_info(void)
{
struct thread_info *ti;
__asm__("extui %0,a1,0,13\n\t"
"xor %0, a1, %0" : "=&r" (ti) : );
return ti;
}
#else /* !__ASSEMBLY__ */
/* how to get the thread information struct from ASM */
#define GET_THREAD_INFO(reg,sp) \
extui reg, sp, 0, 13; \
xor reg, sp, reg
#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_IRET 4 /* return with iret */
#define TIF_MEMDIE 5
#define TIF_RESTORE_SIGMASK 6 /* restore signal mask in do_signal() */
#define TIF_POLLING_NRFLAG 16 /* true if poll_idle() is polling TIF_NEED_RESCHED */
#define TIF_FREEZE 17 /* is freezing for suspend */
#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_IRET (1<<TIF_IRET)
#define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
#define _TIF_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK)
#define _TIF_FREEZE (1<<TIF_FREEZE)
#define _TIF_WORK_MASK 0x0000FFFE /* work to do on interrupt/exception return */
#define _TIF_ALLWORK_MASK 0x0000FFFF /* work to do on any return to u-space */
/*
* Thread-synchronous status.
*
* This is different from the flags in that nobody else
* ever touches our thread-synchronous status, so we don't
* have to worry about atomic accesses.
*/
#define TS_USEDFPU 0x0001 /* FPU was used by this task this quantum (SMP) */
#define THREAD_SIZE 8192 //(2*PAGE_SIZE)
#define THREAD_SIZE_ORDER 1
#endif /* __KERNEL__ */
#endif /* _XTENSA_THREAD_INFO */