korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-23 12:14:10 +08:00
Code Issues Packages Projects Releases Wiki Activity

nohz: Select VIRT_CPU_ACCOUNTING_GEN from full dynticks config

Browse Source 
Turn the full dynticks passive dependency on VIRT_CPU_ACCOUNTING_GEN
to an active one.

The full dynticks Kconfig is currently hidden behind the full dynticks
cputime accounting, which is an awkward and counter-intuitive layout:
the user first has to select the dynticks cputime accounting in order
to make the full dynticks feature to be visible.

We definetly want it the other way around. The usual way to perform
this kind of active dependency is use "select" on the depended target.
Now we can't use the Kconfig "select" instruction when the target is
a "choice".

So this patch inspires on how the RCU subsystem Kconfig interact
with its dependencies on SMP and PREEMPT: we make sure that cputime
accounting can't propose another option than VIRT_CPU_ACCOUNTING_GEN
when NO_HZ_FULL is selected by using the right "depends on" instruction
for each cputime accounting choices.

v2: Keep full dynticks cputime accounting available even without
full dynticks, as per Paul McKenney's suggestion.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Frederic Weisbecker 2013-04-26 15:16:31 +02:00
parent 65e709dc0c
commit c58b0df12a
2 changed files with 6 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
init/Kconfig
View File

@ -306,7 +306,7 @@ choice
# Kind of a stub config for the pure tick based cputime accounting
config TICK_CPU_ACCOUNTING
bool "Simple tick based cputime accounting"
depends on !S390
depends on !S390 && !NO_HZ_FULL
help
This is the basic tick based cputime accounting that maintains
statistics about user, system and idle time spent on per jiffies
@ -316,7 +316,7 @@ config TICK_CPU_ACCOUNTING
config VIRT_CPU_ACCOUNTING_NATIVE
bool "Deterministic task and CPU time accounting"
depends on HAVE_VIRT_CPU_ACCOUNTING
depends on HAVE_VIRT_CPU_ACCOUNTING && !NO_HZ_FULL
select VIRT_CPU_ACCOUNTING
help
Select this option to enable more accurate task and CPU time
@ -346,7 +346,7 @@ config VIRT_CPU_ACCOUNTING_GEN
config IRQ_TIME_ACCOUNTING
bool "Fine granularity task level IRQ time accounting"
depends on HAVE_IRQ_TIME_ACCOUNTING
depends on HAVE_IRQ_TIME_ACCOUNTING && !NO_HZ_FULL
help
Select this option to enable fine granularity task irq time
accounting. This is done by reading a timestamp on each

4
kernel/time/Kconfig
View File

@ -104,11 +104,13 @@ config NO_HZ_FULL
depends on SMP
# RCU_USER_QS dependency
depends on HAVE_CONTEXT_TRACKING
depends on VIRT_CPU_ACCOUNTING_GEN
# VIRT_CPU_ACCOUNTING_GEN dependency
depends on 64BIT
select NO_HZ_COMMON
select RCU_USER_QS
select RCU_NOCB_CPU
select RCU_NOCB_CPU_ALL
select VIRT_CPU_ACCOUNTING_GEN
select CONTEXT_TRACKING_FORCE
select IRQ_WORK
help