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linux/arch/s390/include/asm/processor.h
Heiko Carstens f2db2e6cb3 [S390] pfault: cpu hotplug vs missing completion interrupts
On cpu hot remove a PFAULT CANCEL command is sent to the hypervisor
which in turn will cancel all outstanding pfault requests that have
been issued on that cpu (the same happens with a SIGP cpu reset).

The result is that we end up with uninterruptible processes where
the interrupt that would wake up these processes never arrives.

In order to solve this all processes which wait for a pfault
completion interrupt get woken up after a cpu hot remove. The worst
case that could happen is that they fault again and in turn need to
wait again.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-05-23 10:24:29 +02:00

331 lines
8.3 KiB
C

/*
* include/asm-s390/processor.h
*
* S390 version
* Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
* Author(s): Hartmut Penner (hp@de.ibm.com),
* Martin Schwidefsky (schwidefsky@de.ibm.com)
*
* Derived from "include/asm-i386/processor.h"
* Copyright (C) 1994, Linus Torvalds
*/
#ifndef __ASM_S390_PROCESSOR_H
#define __ASM_S390_PROCESSOR_H
#include <linux/linkage.h>
#include <asm/cpu.h>
#include <asm/page.h>
#include <asm/ptrace.h>
#include <asm/setup.h>
#ifdef __KERNEL__
/*
* Default implementation of macro that returns current
* instruction pointer ("program counter").
*/
#define current_text_addr() ({ void *pc; asm("basr %0,0" : "=a" (pc)); pc; })
static inline void get_cpu_id(struct cpuid *ptr)
{
asm volatile("stidp %0" : "=Q" (*ptr));
}
extern void s390_adjust_jiffies(void);
extern int get_cpu_capability(unsigned int *);
/*
* User space process size: 2GB for 31 bit, 4TB or 8PT for 64 bit.
*/
#ifndef __s390x__
#define TASK_SIZE (1UL << 31)
#define TASK_UNMAPPED_BASE (1UL << 30)
#else /* __s390x__ */
#define TASK_SIZE_OF(tsk) ((tsk)->mm->context.asce_limit)
#define TASK_UNMAPPED_BASE (test_thread_flag(TIF_31BIT) ? \
(1UL << 30) : (1UL << 41))
#define TASK_SIZE TASK_SIZE_OF(current)
#endif /* __s390x__ */
#ifdef __KERNEL__
#ifndef __s390x__
#define STACK_TOP (1UL << 31)
#define STACK_TOP_MAX (1UL << 31)
#else /* __s390x__ */
#define STACK_TOP (1UL << (test_thread_flag(TIF_31BIT) ? 31:42))
#define STACK_TOP_MAX (1UL << 42)
#endif /* __s390x__ */
#endif
#define HAVE_ARCH_PICK_MMAP_LAYOUT
typedef struct {
__u32 ar4;
} mm_segment_t;
/*
* Thread structure
*/
struct thread_struct {
s390_fp_regs fp_regs;
unsigned int acrs[NUM_ACRS];
unsigned long ksp; /* kernel stack pointer */
mm_segment_t mm_segment;
unsigned long prot_addr; /* address of protection-excep. */
unsigned int trap_no;
struct per_regs per_user; /* User specified PER registers */
struct per_event per_event; /* Cause of the last PER trap */
/* pfault_wait is used to block the process on a pfault event */
unsigned long pfault_wait;
struct list_head list;
};
typedef struct thread_struct thread_struct;
/*
* Stack layout of a C stack frame.
*/
#ifndef __PACK_STACK
struct stack_frame {
unsigned long back_chain;
unsigned long empty1[5];
unsigned long gprs[10];
unsigned int empty2[8];
};
#else
struct stack_frame {
unsigned long empty1[5];
unsigned int empty2[8];
unsigned long gprs[10];
unsigned long back_chain;
};
#endif
#define ARCH_MIN_TASKALIGN 8
#define INIT_THREAD { \
.ksp = sizeof(init_stack) + (unsigned long) &init_stack, \
}
/*
* Do necessary setup to start up a new thread.
*/
#define start_thread(regs, new_psw, new_stackp) do { \
set_fs(USER_DS); \
regs->psw.mask = psw_user_bits; \
regs->psw.addr = new_psw | PSW_ADDR_AMODE; \
regs->gprs[15] = new_stackp; \
} while (0)
#define start_thread31(regs, new_psw, new_stackp) do { \
set_fs(USER_DS); \
regs->psw.mask = psw_user32_bits; \
regs->psw.addr = new_psw | PSW_ADDR_AMODE; \
regs->gprs[15] = new_stackp; \
crst_table_downgrade(current->mm, 1UL << 31); \
} while (0)
/* Forward declaration, a strange C thing */
struct task_struct;
struct mm_struct;
struct seq_file;
/* Free all resources held by a thread. */
extern void release_thread(struct task_struct *);
extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
/* Prepare to copy thread state - unlazy all lazy status */
#define prepare_to_copy(tsk) do { } while (0)
/*
* Return saved PC of a blocked thread.
*/
extern unsigned long thread_saved_pc(struct task_struct *t);
extern void show_code(struct pt_regs *regs);
unsigned long get_wchan(struct task_struct *p);
#define task_pt_regs(tsk) ((struct pt_regs *) \
(task_stack_page(tsk) + THREAD_SIZE) - 1)
#define KSTK_EIP(tsk) (task_pt_regs(tsk)->psw.addr)
#define KSTK_ESP(tsk) (task_pt_regs(tsk)->gprs[15])
/*
* Give up the time slice of the virtual PU.
*/
static inline void cpu_relax(void)
{
if (MACHINE_HAS_DIAG44)
asm volatile("diag 0,0,68");
barrier();
}
static inline void psw_set_key(unsigned int key)
{
asm volatile("spka 0(%0)" : : "d" (key));
}
/*
* Set PSW to specified value.
*/
static inline void __load_psw(psw_t psw)
{
#ifndef __s390x__
asm volatile("lpsw %0" : : "Q" (psw) : "cc");
#else
asm volatile("lpswe %0" : : "Q" (psw) : "cc");
#endif
}
/*
* Set PSW mask to specified value, while leaving the
* PSW addr pointing to the next instruction.
*/
static inline void __load_psw_mask (unsigned long mask)
{
unsigned long addr;
psw_t psw;
psw.mask = mask;
#ifndef __s390x__
asm volatile(
" basr %0,0\n"
"0: ahi %0,1f-0b\n"
" st %0,%O1+4(%R1)\n"
" lpsw %1\n"
"1:"
: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
#else /* __s390x__ */
asm volatile(
" larl %0,1f\n"
" stg %0,%O1+8(%R1)\n"
" lpswe %1\n"
"1:"
: "=&d" (addr), "=Q" (psw) : "Q" (psw) : "memory", "cc");
#endif /* __s390x__ */
}
/*
* Function to stop a processor until an interruption occurred
*/
static inline void enabled_wait(void)
{
__load_psw_mask(PSW_BASE_BITS | PSW_MASK_IO | PSW_MASK_EXT |
PSW_MASK_MCHECK | PSW_MASK_WAIT | PSW_DEFAULT_KEY);
}
/*
* Function to drop a processor into disabled wait state
*/
static inline void ATTRIB_NORET disabled_wait(unsigned long code)
{
unsigned long ctl_buf;
psw_t dw_psw;
dw_psw.mask = PSW_BASE_BITS | PSW_MASK_WAIT;
dw_psw.addr = code;
/*
* Store status and then load disabled wait psw,
* the processor is dead afterwards
*/
#ifndef __s390x__
asm volatile(
" stctl 0,0,0(%2)\n"
" ni 0(%2),0xef\n" /* switch off protection */
" lctl 0,0,0(%2)\n"
" stpt 0xd8\n" /* store timer */
" stckc 0xe0\n" /* store clock comparator */
" stpx 0x108\n" /* store prefix register */
" stam 0,15,0x120\n" /* store access registers */
" std 0,0x160\n" /* store f0 */
" std 2,0x168\n" /* store f2 */
" std 4,0x170\n" /* store f4 */
" std 6,0x178\n" /* store f6 */
" stm 0,15,0x180\n" /* store general registers */
" stctl 0,15,0x1c0\n" /* store control registers */
" oi 0x1c0,0x10\n" /* fake protection bit */
" lpsw 0(%1)"
: "=m" (ctl_buf)
: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc");
#else /* __s390x__ */
asm volatile(
" stctg 0,0,0(%2)\n"
" ni 4(%2),0xef\n" /* switch off protection */
" lctlg 0,0,0(%2)\n"
" lghi 1,0x1000\n"
" stpt 0x328(1)\n" /* store timer */
" stckc 0x330(1)\n" /* store clock comparator */
" stpx 0x318(1)\n" /* store prefix register */
" stam 0,15,0x340(1)\n"/* store access registers */
" stfpc 0x31c(1)\n" /* store fpu control */
" std 0,0x200(1)\n" /* store f0 */
" std 1,0x208(1)\n" /* store f1 */
" std 2,0x210(1)\n" /* store f2 */
" std 3,0x218(1)\n" /* store f3 */
" std 4,0x220(1)\n" /* store f4 */
" std 5,0x228(1)\n" /* store f5 */
" std 6,0x230(1)\n" /* store f6 */
" std 7,0x238(1)\n" /* store f7 */
" std 8,0x240(1)\n" /* store f8 */
" std 9,0x248(1)\n" /* store f9 */
" std 10,0x250(1)\n" /* store f10 */
" std 11,0x258(1)\n" /* store f11 */
" std 12,0x260(1)\n" /* store f12 */
" std 13,0x268(1)\n" /* store f13 */
" std 14,0x270(1)\n" /* store f14 */
" std 15,0x278(1)\n" /* store f15 */
" stmg 0,15,0x280(1)\n"/* store general registers */
" stctg 0,15,0x380(1)\n"/* store control registers */
" oi 0x384(1),0x10\n"/* fake protection bit */
" lpswe 0(%1)"
: "=m" (ctl_buf)
: "a" (&dw_psw), "a" (&ctl_buf), "m" (dw_psw) : "cc", "0", "1");
#endif /* __s390x__ */
while (1);
}
/*
* Basic Machine Check/Program Check Handler.
*/
extern void s390_base_mcck_handler(void);
extern void s390_base_pgm_handler(void);
extern void s390_base_ext_handler(void);
extern void (*s390_base_mcck_handler_fn)(void);
extern void (*s390_base_pgm_handler_fn)(void);
extern void (*s390_base_ext_handler_fn)(void);
#define ARCH_LOW_ADDRESS_LIMIT 0x7fffffffUL
#endif
/*
* Helper macro for exception table entries
*/
#ifndef __s390x__
#define EX_TABLE(_fault,_target) \
".section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long " #_fault "," #_target "\n" \
".previous\n"
#else
#define EX_TABLE(_fault,_target) \
".section __ex_table,\"a\"\n" \
" .align 8\n" \
" .quad " #_fault "," #_target "\n" \
".previous\n"
#endif
#endif /* __ASM_S390_PROCESSOR_H */