[PATCHv3 0/5] arm64: initial CPU hotplug support
Mark Rutland
mark.rutland at arm.com
Wed Aug 14 12:20:23 EDT 2013
The following patches add basic HOTPLUG_CPU support to arm64, which
combined with appropriate firmware (e.g. [1]) can be used to power CPUs
up and down dynamically.
I've tested this series with the bootwrapper PSCI implementation I've
placed on linux-arm.org [1] and a modified foundation model dts with a
psci node and each CPU's enable-method set to "psci", using a shell
while repeatedly cycling all cpus off and on:
for C in $(seq 0 3); do
./cyclichotplug.sh $C >/dev/null 2>&1 &
done
---->8----
#!/bin/sh
# cyclichotplug.sh
CPU=$1;
if [ -z "$CPU" ]; then
printf "Usage: $0 <cpu id>\n";
exit 1;
fi
ONLINEFILE=/sys/devices/system/cpu/cpu$CPU/online;
while true; do
echo 0 > $ONLINEFILE;
echo 1 > $ONLINEFILE;
done
---->8----
Since v1 [2]:
* Rebased to v3.11-rc2 to solve cpuinit removal conflicts.
* Removed failure path for cpu_die, it causes more problems than it solves.
* Removed cpu_kill, we don't currently need it.
* Test for cpu_die in op_cpu_disable to fail early and survive when there's no
mechanism for hot unplug.
* Change pr_err on failed cpu_die to a pr_crit.
* Removed dependency on HOTPLUG, which has been obliterated.
Since v2 [3]:
* Rebased to v3.11-rc4 to prevent clash with Xen [4].
* Added proper kerneldoc comments to smp_operations.
* Removed harmful RCU_NONIDLE from cpu_die as per arm
implementation (aa03381046: ARM: smp: Drop RCU_NONIDLE usage in cpu_die()).
* Expanded cpu_die comments.
* Added missing newline to pr_crit in smp_psci_cpu_die().
Thanks,
Mark.
[1] http://linux-arm.org/git?p=boot-wrapper-aarch64.git;a=shortlog;h=refs/heads/psci
[2] http://lists.infradead.org/pipermail/linux-arm-kernel/2013-July/182880.html
[3] http://lists.infradead.org/pipermail/linux-arm-kernel/2013-July/185351.html
[4] http://lists.infradead.org/pipermail/linux-arm-kernel/2013-July/185437.html
Mark Rutland (5):
arm64: reorganise smp_enable_ops
arm64: factor out spin-table boot method
arm64: read enable-method for CPU0
arm64: add CPU_HOTPLUG infrastructure
arm64: add PSCI CPU_OFF-based hotplug support
arch/arm64/Kconfig | 7 ++
arch/arm64/include/asm/irq.h | 1 +
arch/arm64/include/asm/smp.h | 43 ++++++--
arch/arm64/kernel/cputable.c | 2 +-
arch/arm64/kernel/head.S | 12 ++-
arch/arm64/kernel/irq.c | 61 +++++++++++
arch/arm64/kernel/process.c | 7 ++
arch/arm64/kernel/smp.c | 201 ++++++++++++++++++++++---------------
arch/arm64/kernel/smp_psci.c | 54 ++++++++--
arch/arm64/kernel/smp_spin_table.c | 85 +++++++++++++++-
arch/arm64/kernel/vmlinux.lds.S | 1 -
11 files changed, 367 insertions(+), 107 deletions(-)
--
1.8.1.1
More information about the linux-arm-kernel
mailing list