| Message ID | 20240620095233.12185-1-kabel@kernel.org (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | irqchip/armada-370-xp: Use atomic_io_modify() instead of another spinlock | expand |
On Thu, Jun 20, 2024 at 11:52:33AM +0200, Marek Behún wrote: > Use the dedicated atomic_io_modify() instead of hardcoded > spin_lock() + readl() + writel() + spin_unlock() sequence. > > This allows us to drop the irq_controller_lock spinlock from the driver. > > Signed-off-by: Marek Behún <kabel@kernel.org> > --- > Note: the atomic_io_modify() function is defined only for arm platform, > and it is currently used only in 3 drivers: > > drivers/clocksource/timer-armada-370-xp.c > drivers/clocksource/timer-orion.c > drivers/watchdog/orion_wdt.c > > Do we want to use this? Is there some other standardized alternative > that can be used across all platforms? I took a quick look at the code. I don't see anything architecture specific in there. It could be moved somewhere more general. Maybe ask Arnd, he tends to have a good overview for this sort of thing. The patch itself looks fine. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Andrew
diff --git a/drivers/irqchip/irq-armada-370-xp.c b/drivers/irqchip/irq-armada-370-xp.c index 924a574f28ea..8d76e70f8dfd 100644 --- a/drivers/irqchip/irq-armada-370-xp.c +++ b/drivers/irqchip/irq-armada-370-xp.c @@ -512,24 +512,18 @@ static __init void armada_xp_ipi_init(struct device_node *node) set_smp_ipi_range(base_ipi, IPI_DOORBELL_END); } -static DEFINE_RAW_SPINLOCK(irq_controller_lock); - static int armada_xp_set_affinity(struct irq_data *d, const struct cpumask *mask_val, bool force) { irq_hw_number_t hwirq = irqd_to_hwirq(d); - unsigned long reg, mask; int cpu; /* Select a single core from the affinity mask which is online */ cpu = cpumask_any_and(mask_val, cpu_online_mask); - mask = 1UL << cpu_logical_map(cpu); - raw_spin_lock(&irq_controller_lock); - reg = readl(main_int_base + ARMADA_370_XP_INT_SOURCE_CTL(hwirq)); - reg = (reg & (~ARMADA_370_XP_INT_SOURCE_CPU_MASK)) | mask; - writel(reg, main_int_base + ARMADA_370_XP_INT_SOURCE_CTL(hwirq)); - raw_spin_unlock(&irq_controller_lock); + atomic_io_modify(main_int_base + ARMADA_370_XP_INT_SOURCE_CTL(hwirq), + ARMADA_370_XP_INT_SOURCE_CPU_MASK, + BIT(cpu_logical_map(cpu))); irq_data_update_effective_affinity(d, cpumask_of(cpu));
Use the dedicated atomic_io_modify() instead of hardcoded spin_lock() + readl() + writel() + spin_unlock() sequence. This allows us to drop the irq_controller_lock spinlock from the driver. Signed-off-by: Marek Behún <kabel@kernel.org> --- Note: the atomic_io_modify() function is defined only for arm platform, and it is currently used only in 3 drivers: drivers/clocksource/timer-armada-370-xp.c drivers/clocksource/timer-orion.c drivers/watchdog/orion_wdt.c Do we want to use this? Is there some other standardized alternative that can be used across all platforms? --- drivers/irqchip/irq-armada-370-xp.c | 12 +++--------- 1 file changed, 3 insertions(+), 9 deletions(-)