| Message ID | 1376497228-20543-6-git-send-email-mark.rutland@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, 14 Aug 2013, Mark Rutland wrote: > This patch adds support for using PSCI CPU_OFF calls for CPU hotplug. > With this code it is possible to hot unplug CPUs with "psci" as their > boot-method, as long as there's an appropriate cpu_off function id > specified in the psci node. > > Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Nicolas Pitre <nico@linaro.org> > --- > arch/arm64/kernel/smp_psci.c | 30 ++++++++++++++++++++++++++++++ > 1 file changed, 30 insertions(+) > > diff --git a/arch/arm64/kernel/smp_psci.c b/arch/arm64/kernel/smp_psci.c > index 20499bc..e9e5890 100644 > --- a/arch/arm64/kernel/smp_psci.c > +++ b/arch/arm64/kernel/smp_psci.c > @@ -47,9 +47,39 @@ static int smp_psci_cpu_boot(unsigned int cpu) > return err; > } > > +#ifdef CONFIG_HOTPLUG_CPU > +static int smp_psci_cpu_disable(unsigned int cpu) > +{ > + /* Fail early if we don't have CPU_OFF support */ > + if (!psci_ops.cpu_off) > + return -EOPNOTSUPP; > + return 0; > +} > + > +static void smp_psci_cpu_die(unsigned int cpu) > +{ > + int ret; > + /* > + * There are no known implementations of PSCI actually using the > + * power state field, pass a sensible default for now. > + */ > + struct psci_power_state state = { > + .type = PSCI_POWER_STATE_TYPE_POWER_DOWN, > + }; > + > + ret = psci_ops.cpu_off(state); > + > + pr_crit("psci: unable to power off CPU%u (%d)\n", cpu, ret); > +} > +#endif > + > const struct smp_operations smp_psci_ops = { > .name = "psci", > .cpu_init = smp_psci_cpu_init, > .cpu_prepare = smp_psci_cpu_prepare, > .cpu_boot = smp_psci_cpu_boot, > +#ifdef CONFIG_HOTPLUG_CPU > + .cpu_disable = smp_psci_cpu_disable, > + .cpu_die = smp_psci_cpu_die, > +#endif > }; > -- > 1.8.1.1 >
diff --git a/arch/arm64/kernel/smp_psci.c b/arch/arm64/kernel/smp_psci.c index 20499bc..e9e5890 100644 --- a/arch/arm64/kernel/smp_psci.c +++ b/arch/arm64/kernel/smp_psci.c @@ -47,9 +47,39 @@ static int smp_psci_cpu_boot(unsigned int cpu) return err; } +#ifdef CONFIG_HOTPLUG_CPU +static int smp_psci_cpu_disable(unsigned int cpu) +{ + /* Fail early if we don't have CPU_OFF support */ + if (!psci_ops.cpu_off) + return -EOPNOTSUPP; + return 0; +} + +static void smp_psci_cpu_die(unsigned int cpu) +{ + int ret; + /* + * There are no known implementations of PSCI actually using the + * power state field, pass a sensible default for now. + */ + struct psci_power_state state = { + .type = PSCI_POWER_STATE_TYPE_POWER_DOWN, + }; + + ret = psci_ops.cpu_off(state); + + pr_crit("psci: unable to power off CPU%u (%d)\n", cpu, ret); +} +#endif + const struct smp_operations smp_psci_ops = { .name = "psci", .cpu_init = smp_psci_cpu_init, .cpu_prepare = smp_psci_cpu_prepare, .cpu_boot = smp_psci_cpu_boot, +#ifdef CONFIG_HOTPLUG_CPU + .cpu_disable = smp_psci_cpu_disable, + .cpu_die = smp_psci_cpu_die, +#endif };
This patch adds support for using PSCI CPU_OFF calls for CPU hotplug. With this code it is possible to hot unplug CPUs with "psci" as their boot-method, as long as there's an appropriate cpu_off function id specified in the psci node. Signed-off-by: Mark Rutland <mark.rutland@arm.com> --- arch/arm64/kernel/smp_psci.c | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+)