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/processor.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'arch/s390/include/asm/processor.h') 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 v1.2.2