cputime: Make finegrained irqtime accounting generally available
There is no known reason for this option to be unavailable on other
archs than x86. They just need to call enable_sched_clock_irqtime()
if they have a sufficiently finegrained clock to make it working.
Move it to the general option and let the user choose between
it and pure tick based or virtual cputime accounting.
Note that virtual cputime accounting already performs a finegrained
irqtime accounting. CONFIG_IRQ_TIME_ACCOUNTING is a kind of middle ground
between tick and virtual based accounting. So CONFIG_IRQ_TIME_ACCOUNTING
and CONFIG_VIRT_CPU_ACCOUNTING are mutually exclusive choices.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
diff --git a/arch/Kconfig b/arch/Kconfig
index f78de57..101c31a 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -284,4 +284,10 @@
config HAVE_VIRT_CPU_ACCOUNTING
bool
+config HAVE_IRQ_TIME_ACCOUNTING
+ bool
+ help
+ Archs need to ensure they use a high enough resolution clock to
+ support irq time accounting and then call enable_sched_clock_irqtime().
+
source "kernel/gcov/Kconfig"
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 8ec3a1a..b86833a 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -97,6 +97,7 @@
select KTIME_SCALAR if X86_32
select GENERIC_STRNCPY_FROM_USER
select GENERIC_STRNLEN_USER
+ select HAVE_IRQ_TIME_ACCOUNTING
config INSTRUCTION_DECODER
def_bool (KPROBES || PERF_EVENTS || UPROBES)
@@ -796,17 +797,6 @@
making when dealing with multi-core CPU chips at a cost of slightly
increased overhead in some places. If unsure say N here.
-config IRQ_TIME_ACCOUNTING
- bool "Fine granularity task level IRQ time accounting"
- default n
- ---help---
- Select this option to enable fine granularity task irq time
- accounting. This is done by reading a timestamp on each
- transitions between softirq and hardirq state, so there can be a
- small performance impact.
-
- If in doubt, say N here.
-
source "kernel/Kconfig.preempt"
config X86_UP_APIC