From b7394a5f4ce9542666cc68422c3594ea854adc2c Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Thu, 5 Jan 2017 18:11:49 +0100 Subject: sched/cputime, s390: Implement delayed accounting of system time The account_system_time() function is called with a cputime that occurred while running in the kernel. The function detects which context the CPU is currently running in and accounts the time to the correct bucket. This forces the arch code to account the cputime for hardirq and softirq immediately. Such accounting function can be costly and perform unwelcome divisions and multiplications, among others. The arch code can delay the accounting for system time. For s390 the accounting is done once per timer tick and for each task switch. Signed-off-by: Martin Schwidefsky Signed-off-by: Frederic Weisbecker [ Rebase against latest linus tree and move account_system_index_scaled(). ] Acked-by: Thomas Gleixner Cc: Benjamin Herrenschmidt Cc: Christian Borntraeger Cc: Fenghua Yu Cc: Heiko Carstens Cc: Linus Torvalds Cc: Michael Ellerman Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Rik van Riel Cc: Stanislaw Gruszka Cc: Tony Luck Cc: Wanpeng Li Link: http://lkml.kernel.org/r/1483636310-6557-10-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar --- arch/s390/include/asm/lowcore.h | 65 ++++++++++++++++++++------------------- arch/s390/include/asm/processor.h | 3 ++ 2 files changed, 37 insertions(+), 31 deletions(-) (limited to 'arch/s390/include') diff --git a/arch/s390/include/asm/lowcore.h b/arch/s390/include/asm/lowcore.h index 9bfad2ad6312..61261e0e95c0 100644 --- a/arch/s390/include/asm/lowcore.h +++ b/arch/s390/include/asm/lowcore.h @@ -85,53 +85,56 @@ struct lowcore { __u64 mcck_enter_timer; /* 0x02c0 */ __u64 exit_timer; /* 0x02c8 */ __u64 user_timer; /* 0x02d0 */ - __u64 system_timer; /* 0x02d8 */ - __u64 steal_timer; /* 0x02e0 */ - __u64 last_update_timer; /* 0x02e8 */ - __u64 last_update_clock; /* 0x02f0 */ - __u64 int_clock; /* 0x02f8 */ - __u64 mcck_clock; /* 0x0300 */ - __u64 clock_comparator; /* 0x0308 */ + __u64 guest_timer; /* 0x02d8 */ + __u64 system_timer; /* 0x02e0 */ + __u64 hardirq_timer; /* 0x02e8 */ + __u64 softirq_timer; /* 0x02f0 */ + __u64 steal_timer; /* 0x02f8 */ + __u64 last_update_timer; /* 0x0300 */ + __u64 last_update_clock; /* 0x0308 */ + __u64 int_clock; /* 0x0310 */ + __u64 mcck_clock; /* 0x0318 */ + __u64 clock_comparator; /* 0x0320 */ /* Current process. */ - __u64 current_task; /* 0x0310 */ - __u8 pad_0x318[0x320-0x318]; /* 0x0318 */ - __u64 kernel_stack; /* 0x0320 */ + __u64 current_task; /* 0x0328 */ + __u8 pad_0x318[0x320-0x318]; /* 0x0330 */ + __u64 kernel_stack; /* 0x0338 */ /* Interrupt, panic and restart stack. */ - __u64 async_stack; /* 0x0328 */ - __u64 panic_stack; /* 0x0330 */ - __u64 restart_stack; /* 0x0338 */ + __u64 async_stack; /* 0x0340 */ + __u64 panic_stack; /* 0x0348 */ + __u64 restart_stack; /* 0x0350 */ /* Restart function and parameter. */ - __u64 restart_fn; /* 0x0340 */ - __u64 restart_data; /* 0x0348 */ - __u64 restart_source; /* 0x0350 */ + __u64 restart_fn; /* 0x0358 */ + __u64 restart_data; /* 0x0360 */ + __u64 restart_source; /* 0x0368 */ /* Address space pointer. */ - __u64 kernel_asce; /* 0x0358 */ - __u64 user_asce; /* 0x0360 */ + __u64 kernel_asce; /* 0x0370 */ + __u64 user_asce; /* 0x0378 */ /* * The lpp and current_pid fields form a * 64-bit value that is set as program * parameter with the LPP instruction. */ - __u32 lpp; /* 0x0368 */ - __u32 current_pid; /* 0x036c */ + __u32 lpp; /* 0x0380 */ + __u32 current_pid; /* 0x0384 */ /* SMP info area */ - __u32 cpu_nr; /* 0x0370 */ - __u32 softirq_pending; /* 0x0374 */ - __u64 percpu_offset; /* 0x0378 */ - __u64 vdso_per_cpu_data; /* 0x0380 */ - __u64 machine_flags; /* 0x0388 */ - __u32 preempt_count; /* 0x0390 */ - __u8 pad_0x0394[0x0398-0x0394]; /* 0x0394 */ - __u64 gmap; /* 0x0398 */ - __u32 spinlock_lockval; /* 0x03a0 */ - __u32 fpu_flags; /* 0x03a4 */ - __u8 pad_0x03a8[0x0400-0x03a8]; /* 0x03a8 */ + __u32 cpu_nr; /* 0x0388 */ + __u32 softirq_pending; /* 0x038c */ + __u64 percpu_offset; /* 0x0390 */ + __u64 vdso_per_cpu_data; /* 0x0398 */ + __u64 machine_flags; /* 0x03a0 */ + __u32 preempt_count; /* 0x03a8 */ + __u8 pad_0x03ac[0x03b0-0x03ac]; /* 0x03ac */ + __u64 gmap; /* 0x03b0 */ + __u32 spinlock_lockval; /* 0x03b8 */ + __u32 fpu_flags; /* 0x03bc */ + __u8 pad_0x03c0[0x0400-0x03c0]; /* 0x03c0 */ /* Per cpu primary space access list */ __u32 paste[16]; /* 0x0400 */ diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h index 6bca916a5ba0..977a5b6501b8 100644 --- a/arch/s390/include/asm/processor.h +++ b/arch/s390/include/asm/processor.h @@ -111,7 +111,10 @@ struct thread_struct { unsigned int acrs[NUM_ACRS]; unsigned long ksp; /* kernel stack pointer */ unsigned long user_timer; /* task cputime in user space */ + unsigned long guest_timer; /* task cputime in kvm guest */ unsigned long system_timer; /* task cputime in kernel space */ + unsigned long hardirq_timer; /* task cputime in hardirq context */ + unsigned long softirq_timer; /* task cputime in softirq context */ unsigned long sys_call_table; /* system call table address */ mm_segment_t mm_segment; unsigned long gmap_addr; /* address of last gmap fault. */ -- cgit v1.2.3 From 42b425b3360a20ed08e0d735623f389bdf5e4500 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Tue, 31 Jan 2017 04:09:47 +0100 Subject: s390, sched/cputime: Make arch_cpu_idle_time() to return nsecs This way we don't need to deal with cputime_t details from the core code. Signed-off-by: Frederic Weisbecker Cc: Benjamin Herrenschmidt Cc: Fenghua Yu Cc: Heiko Carstens Cc: Linus Torvalds Cc: Martin Schwidefsky Cc: Michael Ellerman Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Rik van Riel Cc: Stanislaw Gruszka Cc: Thomas Gleixner Cc: Tony Luck Cc: Wanpeng Li Link: http://lkml.kernel.org/r/1485832191-26889-32-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar --- arch/s390/include/asm/cputime.h | 2 +- arch/s390/kernel/idle.c | 5 +++-- fs/proc/stat.c | 4 ++-- 3 files changed, 6 insertions(+), 5 deletions(-) (limited to 'arch/s390/include') diff --git a/arch/s390/include/asm/cputime.h b/arch/s390/include/asm/cputime.h index 221b454c734a..9a944815e913 100644 --- a/arch/s390/include/asm/cputime.h +++ b/arch/s390/include/asm/cputime.h @@ -141,7 +141,7 @@ static inline clock_t cputime64_to_clock_t(cputime64_t cputime) return clock; } -cputime64_t arch_cpu_idle_time(int cpu); +u64 arch_cpu_idle_time(int cpu); #define arch_idle_time(cpu) arch_cpu_idle_time(cpu) diff --git a/arch/s390/kernel/idle.c b/arch/s390/kernel/idle.c index 5c0e08e761c3..d3bf69ef42cf 100644 --- a/arch/s390/kernel/idle.c +++ b/arch/s390/kernel/idle.c @@ -84,7 +84,7 @@ static ssize_t show_idle_time(struct device *dev, } DEVICE_ATTR(idle_time_us, 0444, show_idle_time, NULL); -cputime64_t arch_cpu_idle_time(int cpu) +u64 arch_cpu_idle_time(int cpu) { struct s390_idle_data *idle = &per_cpu(s390_idle, cpu); unsigned long long now, idle_enter, idle_exit; @@ -96,7 +96,8 @@ cputime64_t arch_cpu_idle_time(int cpu) idle_enter = ACCESS_ONCE(idle->clock_idle_enter); idle_exit = ACCESS_ONCE(idle->clock_idle_exit); } while (read_seqcount_retry(&idle->seqcount, seq)); - return idle_enter ? ((idle_exit ?: now) - idle_enter) : 0; + + return cputime_to_nsecs(idle_enter ? ((idle_exit ?: now) - idle_enter) : 0); } void arch_cpu_idle_enter(void) diff --git a/fs/proc/stat.c b/fs/proc/stat.c index 44475a44cbf1..e47c3e8c4dfe 100644 --- a/fs/proc/stat.c +++ b/fs/proc/stat.c @@ -27,7 +27,7 @@ static u64 get_idle_time(int cpu) idle = kcpustat_cpu(cpu).cpustat[CPUTIME_IDLE]; if (cpu_online(cpu) && !nr_iowait_cpu(cpu)) - idle += cputime_to_nsecs(arch_idle_time(cpu)); + idle += arch_idle_time(cpu); return idle; } @@ -37,7 +37,7 @@ static u64 get_iowait_time(int cpu) iowait = kcpustat_cpu(cpu).cpustat[CPUTIME_IOWAIT]; if (cpu_online(cpu) && nr_iowait_cpu(cpu)) - iowait += cputime_to_nsecs(arch_idle_time(cpu)); + iowait += arch_idle_time(cpu); return iowait; } -- cgit v1.2.3 From ea3a96d0b4d223fc5e70e06281356762613487bc Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Tue, 31 Jan 2017 04:09:49 +0100 Subject: s390, sched/cputime: Remove unused cputime definitions Since the core doesn't deal with cputime_t anymore, most of these APIs have been left unused. Lets remove these. Signed-off-by: Frederic Weisbecker Cc: Benjamin Herrenschmidt Cc: Fenghua Yu Cc: Heiko Carstens Cc: Linus Torvalds Cc: Martin Schwidefsky Cc: Michael Ellerman Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Rik van Riel Cc: Stanislaw Gruszka Cc: Thomas Gleixner Cc: Tony Luck Cc: Wanpeng Li Link: http://lkml.kernel.org/r/1485832191-26889-34-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar --- arch/s390/include/asm/cputime.h | 107 ---------------------------------------- 1 file changed, 107 deletions(-) (limited to 'arch/s390/include') diff --git a/arch/s390/include/asm/cputime.h b/arch/s390/include/asm/cputime.h index 9a944815e913..d1c407ddf703 100644 --- a/arch/s390/include/asm/cputime.h +++ b/arch/s390/include/asm/cputime.h @@ -25,33 +25,6 @@ static inline unsigned long __div(unsigned long long n, unsigned long base) return n / base; } -#define cputime_one_jiffy jiffies_to_cputime(1) - -/* - * Convert cputime to jiffies and back. - */ -static inline unsigned long cputime_to_jiffies(const cputime_t cputime) -{ - return __div((__force unsigned long long) cputime, CPUTIME_PER_SEC / HZ); -} - -static inline cputime_t jiffies_to_cputime(const unsigned int jif) -{ - return (__force cputime_t)(jif * (CPUTIME_PER_SEC / HZ)); -} - -static inline u64 cputime64_to_jiffies64(cputime64_t cputime) -{ - unsigned long long jif = (__force unsigned long long) cputime; - do_div(jif, CPUTIME_PER_SEC / HZ); - return jif; -} - -static inline cputime64_t jiffies64_to_cputime64(const u64 jif) -{ - return (__force cputime64_t)(jif * (CPUTIME_PER_SEC / HZ)); -} - /* * Convert cputime to microseconds and back. */ @@ -60,86 +33,6 @@ static inline unsigned int cputime_to_usecs(const cputime_t cputime) return (__force unsigned long long) cputime >> 12; } -static inline cputime_t usecs_to_cputime(const unsigned int m) -{ - return (__force cputime_t)(m * CPUTIME_PER_USEC); -} - -#define usecs_to_cputime64(m) usecs_to_cputime(m) - -/* - * Convert cputime to milliseconds and back. - */ -static inline unsigned int cputime_to_secs(const cputime_t cputime) -{ - return __div((__force unsigned long long) cputime, CPUTIME_PER_SEC / 2) >> 1; -} - -static inline cputime_t secs_to_cputime(const unsigned int s) -{ - return (__force cputime_t)(s * CPUTIME_PER_SEC); -} - -/* - * Convert cputime to timespec and back. - */ -static inline cputime_t timespec_to_cputime(const struct timespec *value) -{ - unsigned long long ret = value->tv_sec * CPUTIME_PER_SEC; - return (__force cputime_t)(ret + __div(value->tv_nsec * CPUTIME_PER_USEC, NSEC_PER_USEC)); -} - -static inline void cputime_to_timespec(const cputime_t cputime, - struct timespec *value) -{ - unsigned long long __cputime = (__force unsigned long long) cputime; - value->tv_nsec = (__cputime % CPUTIME_PER_SEC) * NSEC_PER_USEC / CPUTIME_PER_USEC; - value->tv_sec = __cputime / CPUTIME_PER_SEC; -} - -/* - * 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) -{ - unsigned long long ret = value->tv_sec * CPUTIME_PER_SEC; - return (__force cputime_t)(ret + value->tv_usec * CPUTIME_PER_USEC); -} - -static inline void cputime_to_timeval(const cputime_t cputime, - struct timeval *value) -{ - unsigned long long __cputime = (__force unsigned long long) cputime; - value->tv_usec = (__cputime % CPUTIME_PER_SEC) / CPUTIME_PER_USEC; - value->tv_sec = __cputime / CPUTIME_PER_SEC; -} - -/* - * Convert cputime to clock and back. - */ -static inline clock_t cputime_to_clock_t(cputime_t cputime) -{ - unsigned long long clock = (__force unsigned long long) cputime; - do_div(clock, CPUTIME_PER_SEC / USER_HZ); - return clock; -} - -static inline cputime_t clock_t_to_cputime(unsigned long x) -{ - return (__force cputime_t)(x * (CPUTIME_PER_SEC / USER_HZ)); -} - -/* - * Convert cputime64 to clock. - */ -static inline clock_t cputime64_to_clock_t(cputime64_t cputime) -{ - unsigned long long clock = (__force unsigned long long) cputime; - do_div(clock, CPUTIME_PER_SEC / USER_HZ); - return clock; -} u64 arch_cpu_idle_time(int cpu); -- cgit v1.2.3