linux/arch/s390/include/asm/cputime.h

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/*
* include/asm-s390/cputime.h
*
* (C) Copyright IBM Corp. 2004
*
* Author: Martin Schwidefsky <schwidefsky@de.ibm.com>
*/
#ifndef _S390_CPUTIME_H
#define _S390_CPUTIME_H
#include <linux/types.h>
#include <linux/percpu.h>
#include <linux/spinlock.h>
#include <asm/div64.h>
/* We want to use full resolution of the CPU timer: 2**-12 micro-seconds. */
typedef unsigned long long cputime_t;
typedef unsigned long long cputime64_t;
#ifndef __s390x__
static inline unsigned int
__div(unsigned long long n, unsigned int base)
{
register_pair rp;
rp.pair = n >> 1;
asm ("dr %0,%1" : "+d" (rp) : "d" (base >> 1));
return rp.subreg.odd;
}
#else /* __s390x__ */
static inline unsigned int
__div(unsigned long long n, unsigned int base)
{
return n / base;
}
#endif /* __s390x__ */
#define cputime_zero (0ULL)
#define cputime_one_jiffy jiffies_to_cputime(1)
#define cputime_max ((~0UL >> 1) - 1)
#define cputime_add(__a, __b) ((__a) + (__b))
#define cputime_sub(__a, __b) ((__a) - (__b))
#define cputime_div(__a, __n) ({ \
unsigned long long __div = (__a); \
do_div(__div,__n); \
__div; \
})
#define cputime_halve(__a) ((__a) >> 1)
#define cputime_eq(__a, __b) ((__a) == (__b))
#define cputime_gt(__a, __b) ((__a) > (__b))
#define cputime_ge(__a, __b) ((__a) >= (__b))
#define cputime_lt(__a, __b) ((__a) < (__b))
#define cputime_le(__a, __b) ((__a) <= (__b))
#define cputime_to_jiffies(__ct) (__div((__ct), 4096000000ULL / HZ))
#define cputime_to_scaled(__ct) (__ct)
#define jiffies_to_cputime(__hz) ((cputime_t)(__hz) * (4096000000ULL / HZ))
#define cputime64_zero (0ULL)
#define cputime64_add(__a, __b) ((__a) + (__b))
#define cputime_to_cputime64(__ct) (__ct)
static inline u64
cputime64_to_jiffies64(cputime64_t cputime)
{
do_div(cputime, 4096000000ULL / HZ);
return cputime;
}
/*
* Convert cputime to microseconds and back.
*/
static inline unsigned int
cputime_to_usecs(const cputime_t cputime)
{
return cputime_div(cputime, 4096);
}
static inline cputime_t
usecs_to_cputime(const unsigned int m)
{
return (cputime_t) m * 4096;
}
/*
* Convert cputime to milliseconds and back.
*/
static inline unsigned int
cputime_to_secs(const cputime_t cputime)
{
return __div(cputime, 2048000000) >> 1;
}
static inline cputime_t
secs_to_cputime(const unsigned int s)
{
return (cputime_t) s * 4096000000ULL;
}
/*
* Convert cputime to timespec and back.
*/
static inline cputime_t
timespec_to_cputime(const struct timespec *value)
{
return value->tv_nsec * 4096 / 1000 + (u64) value->tv_sec * 4096000000ULL;
}
static inline void
cputime_to_timespec(const cputime_t cputime, struct timespec *value)
{
#ifndef __s390x__
register_pair rp;
rp.pair = cputime >> 1;
asm ("dr %0,%1" : "+d" (rp) : "d" (2048000000UL));
value->tv_nsec = rp.subreg.even * 1000 / 4096;
value->tv_sec = rp.subreg.odd;
#else
value->tv_nsec = (cputime % 4096000000ULL) * 1000 / 4096;
value->tv_sec = cputime / 4096000000ULL;
#endif
}
/*
* Convert cputime to timeval and back.
* Since cputime and timeval have the same resolution (microseconds)
* this is easy.
*/
static inline cputime_t
timeval_to_cputime(const struct timeval *value)
{
return value->tv_usec * 4096 + (u64) value->tv_sec * 4096000000ULL;
}
static inline void
cputime_to_timeval(const cputime_t cputime, struct timeval *value)
{
#ifndef __s390x__
register_pair rp;
rp.pair = cputime >> 1;
asm ("dr %0,%1" : "+d" (rp) : "d" (2048000000UL));
value->tv_usec = rp.subreg.even / 4096;
value->tv_sec = rp.subreg.odd;
#else
value->tv_usec = (cputime % 4096000000ULL) / 4096;
value->tv_sec = cputime / 4096000000ULL;
#endif
}
/*
* Convert cputime to clock and back.
*/
static inline clock_t
cputime_to_clock_t(cputime_t cputime)
{
[S390] cputime: fix overflow on 31 bit systems The cputime_to_msecs / cputime_to_clock_t and cputime64_to_clock_t cause fixpoint divide exceptions if the cputime is too large. On a machine that collected 49.7 days worth of idle time reading from /proc/stat will generate oopses like this: Kernel BUG at 001b0c92 [verbose debug info unavailable] fixpoint divide exception: 0009 [#13] SMP Modules linked in: ipv6 CPU: 1 Tainted: G D 2.6.27.10 #5 Process cat (pid: 21352, task: 1fb34138, ksp: 1d2a3d98) Krnl PSW : 070c2000 801b0c92 (show_stat+0x2ca/0x68c) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:2 PM:0 Krnl GPRS: 00000001 00001388 00000bb8 0015d2a1 00000000 00000000 000003e8 0001fd91 00000000 00000000 0000129d eecd2ff0 1cc533b9 0036f780 801b0bce 1d2a3cc0 Krnl Code: 801b0c86: f18890abf198 mvo 171(9,%r9),408(9,%r15) 801b0c8c: 98abf170 lm %r10,%r11,368(%r15) 801b0c90: 1da1 dr %r10,%r1 >801b0c92: 90abf170 stm %r10,%r11,368(%r15) 801b0c96: 98abf190 lm %r10,%r11,400(%r15) 801b0c9a: 1da1 dr %r10,%r1 801b0c9c: 90abf190 stm %r10,%r11,400(%r15) 801b0ca0: 18a3 lr %r10,%r3 Call Trace: ([<00000000001b09f4>] show_stat+0x2c/0x68c) [<000000000018dcee>] seq_read+0xb2/0x364 [<00000000001a9980>] proc_reg_read+0x68/0x98 [<00000000001705ee>] vfs_read+0x6e/0xe8 [<0000000000170732>] sys_read+0x36/0x78 [<000000000010f750>] sysc_do_restart+0x12/0x16 [<0000000077f3ad6a>] 0x77f3ad6a <4>---[ end trace 1436ea9559d3de9e ]--- Reported-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-10-29 14:04:12 +00:00
return cputime_div(cputime, 4096000000ULL / USER_HZ);
}
static inline cputime_t
clock_t_to_cputime(unsigned long x)
{
return (cputime_t) x * (4096000000ULL / USER_HZ);
}
/*
* Convert cputime64 to clock.
*/
static inline clock_t
cputime64_to_clock_t(cputime64_t cputime)
{
[S390] cputime: fix overflow on 31 bit systems The cputime_to_msecs / cputime_to_clock_t and cputime64_to_clock_t cause fixpoint divide exceptions if the cputime is too large. On a machine that collected 49.7 days worth of idle time reading from /proc/stat will generate oopses like this: Kernel BUG at 001b0c92 [verbose debug info unavailable] fixpoint divide exception: 0009 [#13] SMP Modules linked in: ipv6 CPU: 1 Tainted: G D 2.6.27.10 #5 Process cat (pid: 21352, task: 1fb34138, ksp: 1d2a3d98) Krnl PSW : 070c2000 801b0c92 (show_stat+0x2ca/0x68c) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:2 PM:0 Krnl GPRS: 00000001 00001388 00000bb8 0015d2a1 00000000 00000000 000003e8 0001fd91 00000000 00000000 0000129d eecd2ff0 1cc533b9 0036f780 801b0bce 1d2a3cc0 Krnl Code: 801b0c86: f18890abf198 mvo 171(9,%r9),408(9,%r15) 801b0c8c: 98abf170 lm %r10,%r11,368(%r15) 801b0c90: 1da1 dr %r10,%r1 >801b0c92: 90abf170 stm %r10,%r11,368(%r15) 801b0c96: 98abf190 lm %r10,%r11,400(%r15) 801b0c9a: 1da1 dr %r10,%r1 801b0c9c: 90abf190 stm %r10,%r11,400(%r15) 801b0ca0: 18a3 lr %r10,%r3 Call Trace: ([<00000000001b09f4>] show_stat+0x2c/0x68c) [<000000000018dcee>] seq_read+0xb2/0x364 [<00000000001a9980>] proc_reg_read+0x68/0x98 [<00000000001705ee>] vfs_read+0x6e/0xe8 [<0000000000170732>] sys_read+0x36/0x78 [<000000000010f750>] sysc_do_restart+0x12/0x16 [<0000000077f3ad6a>] 0x77f3ad6a <4>---[ end trace 1436ea9559d3de9e ]--- Reported-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-10-29 14:04:12 +00:00
return cputime_div(cputime, 4096000000ULL / USER_HZ);
}
struct s390_idle_data {
unsigned int sequence;
unsigned long long idle_count;
unsigned long long idle_enter;
unsigned long long idle_time;
int nohz_delay;
};
DECLARE_PER_CPU(struct s390_idle_data, s390_idle);
void vtime_start_cpu(__u64 int_clock, __u64 enter_timer);
cputime64_t s390_get_idle_time(int cpu);
#define arch_idle_time(cpu) s390_get_idle_time(cpu)
static inline void s390_idle_check(struct pt_regs *regs, __u64 int_clock,
__u64 enter_timer)
{
if (regs->psw.mask & PSW_MASK_WAIT)
vtime_start_cpu(int_clock, enter_timer);
}
static inline int s390_nohz_delay(int cpu)
{
return per_cpu(s390_idle, cpu).nohz_delay != 0;
}
#define arch_needs_cpu(cpu) s390_nohz_delay(cpu)
#endif /* _S390_CPUTIME_H */