From 91a29af413def677495e447fb9a06957ebc8bed5 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Thu, 7 Jul 2022 19:23:09 +0100 Subject: gpio: Remove dynamic allocation from populate_parent_alloc_arg() The gpiolib is unique in the way it uses intermediate fwspecs when feeding an interrupt specifier to the parent domain, as it relies on the populate_parent_alloc_arg() callback to perform a dynamic allocation. This is pretty inefficient (we free the structure almost immediately), and the only reason this isn't a stack allocation is that our ThunderX friend uses MSIs rather than a FW-constructed structure. Let's solve it by providing a new type composed of the union of a struct irq_fwspec and a msi_info_t, which satisfies both requirements. This allows us to use a stack allocation, and we can move the handful of users to this new scheme. Also perform some additional cleanup, such as getting rid of the stub versions of the irq_domain_translate_*cell helpers, which are never used when CONFIG_IRQ_DOMAIN_HIERARCHY isn't selected. Tested on a Tegra186. Reviewed-by: Linus Walleij Signed-off-by: Marc Zyngier Cc: Daniel Palmer Cc: Romain Perier Cc: Bartosz Golaszewski Cc: Thierry Reding Cc: Jonathan Hunter Cc: Robert Richter Cc: Nobuhiro Iwamatsu Cc: Andy Gross Cc: Bjorn Andersson Acked-by: Bartosz Golaszewski Link: https://lore.kernel.org/r/20220707182314.66610-2-prabhakar.mahadev-lad.rj@bp.renesas.com --- drivers/gpio/gpio-tegra.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) (limited to 'drivers/gpio/gpio-tegra.c') diff --git a/drivers/gpio/gpio-tegra.c b/drivers/gpio/gpio-tegra.c index ff2d2a1f9c73..e4fb4cb38a0f 100644 --- a/drivers/gpio/gpio-tegra.c +++ b/drivers/gpio/gpio-tegra.c @@ -443,15 +443,12 @@ static int tegra_gpio_child_to_parent_hwirq(struct gpio_chip *chip, return 0; } -static void *tegra_gpio_populate_parent_fwspec(struct gpio_chip *chip, - unsigned int parent_hwirq, - unsigned int parent_type) +static int tegra_gpio_populate_parent_fwspec(struct gpio_chip *chip, + union gpio_irq_fwspec *gfwspec, + unsigned int parent_hwirq, + unsigned int parent_type) { - struct irq_fwspec *fwspec; - - fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL); - if (!fwspec) - return NULL; + struct irq_fwspec *fwspec = &gfwspec->fwspec; fwspec->fwnode = chip->irq.parent_domain->fwnode; fwspec->param_count = 3; @@ -459,7 +456,7 @@ static void *tegra_gpio_populate_parent_fwspec(struct gpio_chip *chip, fwspec->param[1] = parent_hwirq; fwspec->param[2] = parent_type; - return fwspec; + return 0; } #ifdef CONFIG_PM_SLEEP -- cgit