Re: [PATCH v3 5/9] irqchip/gic-v3: Gather all ACPI specific data in a single structure

[Christoffer Dall <christoffer.dall@linaro.org>]

On Tue, Mar 08, 2016 at 11:29:29AM +0000, Julien Grall wrote:
> Even though all the variables aren't marked with __initdata, they are
> only used during initialization. So the structure is marked with
> __initdata.

Not sure I understand this commit message.

As I see it, this commit includes two changes:

1. Mark the variables only used during init with __initdata

2. Move the variables into a structure

If I get that right, can you argue for both changes?

Thanks,
-Christoffer

> 
> Signed-off-by: Julien Grall <julien.grall@arm.com>
> 
> ---
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Jason Cooper <jason@lakedaemon.net>
> Cc: Marc Zyngier <marc.zyngier@arm.com>
> 
>     Changes in v3:
>         - Patch added
> ---
>  drivers/irqchip/irq-gic-v3.c | 60 ++++++++++++++++++++++++--------------------
>  1 file changed, 33 insertions(+), 27 deletions(-)
> 
> diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
> index 5b7d3c2..50e87e6 100644
> --- a/drivers/irqchip/irq-gic-v3.c
> +++ b/drivers/irqchip/irq-gic-v3.c
> @@ -968,19 +968,22 @@ out_unmap_dist:
>  IRQCHIP_DECLARE(gic_v3, "arm,gic-v3", gic_of_init);
>  
>  #ifdef CONFIG_ACPI
> -static void __iomem *dist_base;
> -static struct redist_region *redist_regs __initdata;
> -static u32 nr_redist_regions __initdata;
> -static bool single_redist;
> +static struct
> +{
> +	void __iomem *dist_base;
> +	struct redist_region *redist_regs;
> +	u32 nr_redist_regions;
> +	bool single_redist;
> +} acpi_data __initdata;
>  
>  static void __init
>  gic_acpi_register_redist(phys_addr_t phys_base, void __iomem *redist_base)
>  {
>  	static int count = 0;
>  
> -	redist_regs[count].phys_base = phys_base;
> -	redist_regs[count].redist_base = redist_base;
> -	redist_regs[count].single_redist = single_redist;
> +	acpi_data.redist_regs[count].phys_base = phys_base;
> +	acpi_data.redist_regs[count].redist_base = redist_base;
> +	acpi_data.redist_regs[count].single_redist = acpi_data.single_redist;
>  	count++;
>  }
>  
> @@ -1008,7 +1011,7 @@ gic_acpi_parse_madt_gicc(struct acpi_subtable_header *header,
>  {
>  	struct acpi_madt_generic_interrupt *gicc =
>  				(struct acpi_madt_generic_interrupt *)header;
> -	u32 reg = readl_relaxed(dist_base + GICD_PIDR2) & GIC_PIDR2_ARCH_MASK;
> +	u32 reg = readl_relaxed(acpi_data.dist_base + GICD_PIDR2) & GIC_PIDR2_ARCH_MASK;
>  	u32 size = reg == GIC_PIDR2_ARCH_GICv4 ? SZ_64K * 4 : SZ_64K * 2;
>  	void __iomem *redist_base;
>  
> @@ -1025,7 +1028,7 @@ static int __init gic_acpi_collect_gicr_base(void)
>  	acpi_tbl_entry_handler redist_parser;
>  	enum acpi_madt_type type;
>  
> -	if (single_redist) {
> +	if (acpi_data.single_redist) {
>  		type = ACPI_MADT_TYPE_GENERIC_INTERRUPT;
>  		redist_parser = gic_acpi_parse_madt_gicc;
>  	} else {
> @@ -1076,14 +1079,14 @@ static int __init gic_acpi_count_gicr_regions(void)
>  	count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_REDISTRIBUTOR,
>  				      gic_acpi_match_gicr, 0);
>  	if (count > 0) {
> -		single_redist = false;
> +		acpi_data.single_redist = false;
>  		return count;
>  	}
>  
>  	count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_INTERRUPT,
>  				      gic_acpi_match_gicc, 0);
>  	if (count > 0)
> -		single_redist = true;
> +		acpi_data.single_redist = true;
>  
>  	return count;
>  }
> @@ -1103,7 +1106,7 @@ static bool __init acpi_validate_gic_table(struct acpi_subtable_header *header,
>  	if (count <= 0)
>  		return false;
>  
> -	nr_redist_regions = count;
> +	acpi_data.nr_redist_regions = count;
>  	return true;
>  }
>  
> @@ -1114,25 +1117,28 @@ gic_acpi_init(struct acpi_subtable_header *header, const unsigned long end)
>  {
>  	struct acpi_madt_generic_distributor *dist;
>  	struct fwnode_handle *domain_handle;
> +	size_t size;
>  	int i, err;
>  
>  	/* Get distributor base address */
>  	dist = (struct acpi_madt_generic_distributor *)header;
> -	dist_base = ioremap(dist->base_address, ACPI_GICV3_DIST_MEM_SIZE);
> -	if (!dist_base) {
> +	acpi_data.dist_base = ioremap(dist->base_address,
> +				      ACPI_GICV3_DIST_MEM_SIZE);
> +	if (!acpi_data.dist_base) {
>  		pr_err("Unable to map GICD registers\n");
>  		return -ENOMEM;
>  	}
>  
> -	err = gic_validate_dist_version(dist_base);
> +	err = gic_validate_dist_version(acpi_data.dist_base);
>  	if (err) {
> -		pr_err("No distributor detected at @%p, giving up", dist_base);
> +		pr_err("No distributor detected at @%p, giving up",
> +		       acpi_data.dist_base);
>  		goto out_dist_unmap;
>  	}
>  
> -	redist_regs = kzalloc(sizeof(*redist_regs) * nr_redist_regions,
> -			      GFP_KERNEL);
> -	if (!redist_regs) {
> +	size = sizeof(*acpi_data.redist_regs) * acpi_data.nr_redist_regions;
> +	acpi_data.redist_regs = kzalloc(size, GFP_KERNEL);
> +	if (!acpi_data.redist_regs) {
>  		err = -ENOMEM;
>  		goto out_dist_unmap;
>  	}
> @@ -1141,14 +1147,14 @@ gic_acpi_init(struct acpi_subtable_header *header, const unsigned long end)
>  	if (err)
>  		goto out_redist_unmap;
>  
> -	domain_handle = irq_domain_alloc_fwnode(dist_base);
> +	domain_handle = irq_domain_alloc_fwnode(acpi_data.dist_base);
>  	if (!domain_handle) {
>  		err = -ENOMEM;
>  		goto out_redist_unmap;
>  	}
>  
> -	err = gic_init_bases(dist_base, redist_regs, nr_redist_regions, 0,
> -			     domain_handle);
> +	err = gic_init_bases(acpi_data.dist_base, acpi_data.redist_regs,
> +			     acpi_data.nr_redist_regions, 0, domain_handle);
>  	if (err)
>  		goto out_fwhandle_free;
>  
> @@ -1158,12 +1164,12 @@ gic_acpi_init(struct acpi_subtable_header *header, const unsigned long end)
>  out_fwhandle_free:
>  	irq_domain_free_fwnode(domain_handle);
>  out_redist_unmap:
> -	for (i = 0; i < nr_redist_regions; i++)
> -		if (redist_regs[i].redist_base)
> -			iounmap(redist_regs[i].redist_base);
> -	kfree(redist_regs);
> +	for (i = 0; i < acpi_data.nr_redist_regions; i++)
> +		if (acpi_data.redist_regs[i].redist_base)
> +			iounmap(acpi_data.redist_regs[i].redist_base);
> +	kfree(acpi_data.redist_regs);
>  out_dist_unmap:
> -	iounmap(dist_base);
> +	iounmap(acpi_data.dist_base);
>  	return err;
>  }
>  IRQCHIP_ACPI_DECLARE(gic_v3, ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR,
> -- 
> 1.9.1
>