Re: [PATCH 2/3] drivers/irqchip: update supports_deactivate static key to modern api
From: Marc Zyngier
Date: Mon Mar 26 2018 - 04:17:45 EST
Hi Davidlohr,
On 25/03/18 20:10, Davidlohr Bueso wrote:
> Minor changes in semantics -- key init is true; replace
>
> static_key_slow_dec with static_branch_disable
> static_key_true with static_branch_likely
>
> The first is because we never actually do any couterpart incs,
> thus there is really no reference counting semantics going on.
> Use the more proper static_branch_disable() construct.
>
> Also added a '_key' suffix to supports_deactivate, for better
> self documentation.
>
> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Cc: Jason Cooper <jason@xxxxxxxxxxxxxx>
> Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
> Signed-off-by: Davidlohr Bueso <dbueso@xxxxxxx>
> ---
> drivers/irqchip/irq-gic-v3.c | 20 ++++++++++----------
> drivers/irqchip/irq-gic.c | 22 +++++++++++-----------
> 2 files changed, 21 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
> index 56c8de84a72b..f32b1814278b 100644
> --- a/drivers/irqchip/irq-gic-v3.c
> +++ b/drivers/irqchip/irq-gic-v3.c
> @@ -61,7 +61,7 @@ struct gic_chip_data {
> };
>
> static struct gic_chip_data gic_data __read_mostly;
> -static struct static_key supports_deactivate = STATIC_KEY_INIT_TRUE;
> +DEFINE_STATIC_KEY_TRUE(supports_deactivate_key);
When you combine this...
[...]
> diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c
> index ac2e62d613d1..9b7630cee56c 100644
> --- a/drivers/irqchip/irq-gic.c
> +++ b/drivers/irqchip/irq-gic.c
> @@ -121,7 +121,7 @@ static DEFINE_RAW_SPINLOCK(cpu_map_lock);
> #define NR_GIC_CPU_IF 8
> static u8 gic_cpu_map[NR_GIC_CPU_IF] __read_mostly;
>
> -static struct static_key supports_deactivate = STATIC_KEY_INIT_TRUE;
> +DEFINE_STATIC_KEY_TRUE(supports_deactivate_key);
...with that, bad things happen:
drivers/irqchip/irq-gic-v3.o:(.data+0x278): multiple definition of `supports_deactivate_key'
drivers/irqchip/irq-gic.o:(.data+0x18): first defined here
Makefile:1032: recipe for target 'vmlinux' failed
make: *** [vmlinux] Error 1
Thanks,
M.
--
Jazz is not dead. It just smells funny...