[RFC PATCH 0/8] printk: Make it usable on nohz CPUs v2

Frederic Weisbecker
2012-10-20T16:22:59Z

Hi,

So the design is not quite the same here. Instead of using the ad hoc
printk_tick() in periodic mode and irq_work on nohz mode, printk
is now always using irq_work.

In turn, irq_work subsystem is able to let enqueuers choose between IPI
or lazy tick hook to execute works, and that in order to avoid IPI storm
when we have lots of enqueuing of non-urgent works like klogd wakeup
in short period of time so this keeps the old printk_tick behaviour.

It also teaches irq_work to handle nohz mode.

Warning: only compile tested in x86 for now.

Frederic Weisbecker (8):
irq_work: Move irq_work_raise() declaration/default definition to
arch headers
irq_work: Let the arch tell us about self-IPI support
x86: Implement arch_irq_work_has_ipi()
nohz: Add API to check tick state
irq_work: Make self-IPIs optable
irq_work: Handle queuing without IPI support in dyntick idle mode
irq_work: Remove CONFIG_HAVE_IRQ_WORK
printk: Wake up klogd using irq_work

arch/alpha/Kconfig | 1 -
arch/alpha/include/asm/irq_work.h | 9 +++++
arch/alpha/kernel/time.c | 2 +-
arch/arm/Kconfig | 1 -
arch/arm/include/asm/irq_work.h | 1 +
arch/arm64/Kconfig | 1 -
arch/arm64/include/asm/irq_work.h | 1 +
arch/blackfin/Kconfig | 1 -
arch/blackfin/include/asm/irq_work.h | 1 +
arch/frv/Kconfig | 1 -
arch/frv/include/asm/irq_work.h | 1 +
arch/hexagon/Kconfig | 1 -
arch/hexagon/include/asm/irq_work.h | 1 +
arch/mips/Kconfig | 1 -
arch/mips/include/asm/irq_work.h | 1 +
arch/parisc/Kconfig | 1 -
arch/parisc/include/asm/irq_work.h | 1 +
arch/powerpc/Kconfig | 1 -
arch/powerpc/include/asm/irq_work.h | 8 ++++
arch/powerpc/kernel/time.c | 2 +-
arch/s390/Kconfig | 1 -
arch/s390/include/asm/irq_work.h | 1 +
arch/sh/Kconfig | 1 -
arch/sh/include/asm/irq_work.h | 1 +
arch/sparc/Kconfig | 1 -
arch/sparc/include/asm/irq_work.h | 8 ++++
arch/sparc/kernel/pcr.c | 2 +-
arch/x86/Kconfig | 1 -
arch/x86/include/asm/irq_work.h | 15 ++++++++
arch/x86/kernel/cpu/mcheck/mce.c | 2 +-
arch/x86/kernel/irq_work.c | 6 ++--
arch/x86/kvm/pmu.c | 2 +-
drivers/acpi/apei/ghes.c | 2 +-
drivers/staging/iio/trigger/Kconfig | 1 -
drivers/staging/iio/trigger/iio-trig-sysfs.c | 2 +-
include/asm-generic/irq_work.h | 23 ++++++++++++
include/linux/irq_work.h | 9 ++++-
include/linux/printk.h | 3 --
include/linux/tick.h | 17 ++++++++-
init/Kconfig | 5 +--
kernel/events/core.c | 4 +-
kernel/events/ring_buffer.c | 2 +-
kernel/irq_work.c | 48 +++++++++++++++++++------
kernel/printk.c | 14 ++++----
kernel/time/tick-sched.c | 6 ++--
kernel/timer.c | 1 -
46 files changed, 156 insertions(+), 59 deletions(-)
create mode 100644 arch/alpha/include/asm/irq_work.h
create mode 100644 arch/arm/include/asm/irq_work.h
create mode 100644 arch/arm64/include/asm/irq_work.h
create mode 100644 arch/blackfin/include/asm/irq_work.h
create mode 100644 arch/frv/include/asm/irq_work.h
create mode 100644 arch/hexagon/include/asm/irq_work.h
create mode 100644 arch/mips/include/asm/irq_work.h
create mode 100644 arch/parisc/include/asm/irq_work.h
create mode 100644 arch/powerpc/include/asm/irq_work.h
create mode 100644 arch/s390/include/asm/irq_work.h
create mode 100644 arch/sh/include/asm/irq_work.h
create mode 100644 arch/sparc/include/asm/irq_work.h
create mode 100644 arch/x86/include/asm/irq_work.h
create mode 100644 include/asm-generic/irq_work.h

--
1.7.5.4