Re: [PATCH -v2 2/2] genericirq: change ack/mask in irq_chip to take irq_desc instead of irq

From: Eric W. Biederman
Date: Wed Feb 24 2010 - 16:38:17 EST


Yinghai Lu <yinghai@xxxxxxxxxx> writes:

> will have
> void (*ack)(struct irq_desc *desc);
> void (*mask)(struct irq_desc *desc);
> void (*mask_ack)(struct irq_desc *desc);
> void (*unmask)(struct irq_desc *desc);
> void (*eoi)(struct irq_desc *desc);
>
> so for sparseirq with raidix tree, we don't call extra irq_to_desc, and could use desc directly

Overall this looks pretty decent. This look pretty complete.
How many platforms did you manage to compile test this on?

I have found a couple of issues (see below).

A few times you change a bit more than is necessary which is a bit
spooky in a patch this far ranging.

Reading through this patch to review it took an uncomfortably long
time.


> -v2: change all member of irq_chip to use desc only.
>
> Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>

> Index: linux-2.6/arch/alpha/kernel/sys_rx164.c
> ===================================================================
> --- linux-2.6.orig/arch/alpha/kernel/sys_rx164.c
> +++ linux-2.6/arch/alpha/kernel/sys_rx164.c
> static void
> -rx164_end_irq(unsigned int irq)
> +rx164_end_irq(struct irq_desc *desc)
> {
> - if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
> - rx164_enable_irq(irq);
> + if (!(desc_.status & (IRQ_DISABLED|IRQ_INPROGRESS)))
> + rx164_enable_irq(desc);
> }

You have mispelled desc-> here.

> Index: linux-2.6/arch/arm/mach-s3c2410/bast-irq.c
> ===================================================================
> --- linux-2.6.orig/arch/arm/mach-s3c2410/bast-irq.c
> +++ linux-2.6/arch/arm/mach-s3c2410/bast-irq.c
> @@ -75,31 +75,31 @@ static unsigned char bast_pc104_irqmasks
>
> static void
> -bast_pc104_maskack(unsigned int irqno)
> +bast_pc104_maskack(struct irq_desc *desc)
> {
> - struct irq_desc *desc = irq_desc + IRQ_ISA;
> -
> - bast_pc104_mask(irqno);
> - desc->chip->ack(IRQ_ISA);
> + bast_pc104_mask(desc);
> + desc->chip->ack(desc);
> }

This is not a trivial 1 to 1 conversion. IRQ_ISA != irqno.
I don't know if the original code is broken here or
just very peculiar.

> static struct irq_chip s3c_irq_cam = {
> Index: linux-2.6/arch/arm/plat-s3c64xx/irq-eint.c
> ===================================================================
> --- linux-2.6.orig/arch/arm/plat-s3c64xx/irq-eint.c
> +++ linux-2.6/arch/arm/plat-s3c64xx/irq-eint.c

> -static void s3c_irq_eint_maskack(unsigned int irq)
> +static void s3c_irq_eint_maskack(struct irq_desc *desc)
> {
> + unsigned int irq = desc->irq;
> /* compiler should in-line these */
> - s3c_irq_eint_mask(irq);
> - s3c_irq_eint_ack(irq);
> + s3c_irq_eint_mask(irq, desc);
> + s3c_irq_eint_ack(irq, desc);
> }

It appears this function has the wrong conversion.

> Index: linux-2.6/arch/blackfin/mach-common/ints-priority.c
> ===================================================================
> --- linux-2.6.orig/arch/blackfin/mach-common/ints-priority.c
> +++ linux-2.6/arch/blackfin/mach-common/ints-priority.c
> @@ -925,7 +938,7 @@ static void bfin_demux_gpio_irq(unsigned
> static struct irq_chip bfin_gpio_irqchip = {
> .name = "GPIO",
> .ack = bfin_gpio_ack_irq,
> - .mask = bfin_gpio_mask_irq,
> + .mask = bfin_gpio_mask_irq_desc,

You have not introduced bfin_gpio_mask_irq_desc ...

> .mask_ack = bfin_gpio_mask_ack_irq,
> .unmask = bfin_gpio_unmask_irq,
> .disable = bfin_gpio_mask_irq,

> Index: linux-2.6/arch/ia64/kernel/iosapic.c
> ===================================================================
> --- linux-2.6.orig/arch/ia64/kernel/iosapic.c
> +++ linux-2.6/arch/ia64/kernel/iosapic.c
> @@ -267,6 +267,10 @@ static void
> nop (unsigned int irq)
> {
> /* do nothing... */
> +static void
> +nop_desc(struct irq_desc *desc)
> +{
> + /* do nothing... */
> }

Two things here.
- nop has no closing brace.
- You should just be able to convert nop here, and not
need to introduce nop_desc.

> #define iosapic_shutdown_level_irq mask_irq
> #define iosapic_enable_level_irq unmask_irq
> #define iosapic_disable_level_irq mask_irq
> -#define iosapic_ack_level_irq nop
> +#define iosapic_ack_level_irq nop_desc

Making this change unnecessary.

> #define iosapic_enable_edge_irq unmask_irq
> #define iosapic_disable_edge_irq nop
> -#define iosapic_end_edge_irq nop
> +#define iosapic_end_edge_irq nop_desc

and this change unnecessary.

>
> static struct irq_chip irq_type_iosapic_edge = {
> .name = "IO-SAPIC-edge",

> Index: linux-2.6/arch/m68knommu/platform/coldfire/intc-simr.c
> ===================================================================
> --- linux-2.6.orig/arch/m68knommu/platform/coldfire/intc-simr.c
> +++ linux-2.6/arch/m68knommu/platform/coldfire/intc-simr.c
> @@ -40,6 +42,7 @@ static void intc_irq_unmask(unsigned int
>
> static int intc_irq_set_type(unsigned int irq, unsigned int type)
> {
> + unsigned int irq = desc->irq;

This function does not take a desc argument.

> if (irq >= MCFINT_VECBASE) {
> if (irq < MCFINT_VECBASE + 64)
> __raw_writeb(5, MCFINTC0_ICR0 + irq - MCFINT_VECBASE);

> Index: linux-2.6/arch/mips/alchemy/common/irq.c
> ===================================================================
> --- linux-2.6.orig/arch/mips/alchemy/common/irq.c
> +++ linux-2.6/arch/mips/alchemy/common/irq.c
> @@ -288,17 +288,19 @@ void restore_au1xxx_intctl(void)
> #endif /* CONFIG_PM */
>
>
> -static void au1x_ic0_unmask(unsigned int irq_nr)
> +static void au1x_ic0_unmask(struct irq_desc *desc)
> {
> - unsigned int bit = irq_nr - AU1000_INTC0_INT_BASE;
> + unsigned int irq = desc->irq;
> + unsigned int bit = irq_ - AU1000_INTC0_INT_BASE;

You misspelled irq there.

> au_writel(1 << bit, IC0_MASKSET);
> au_writel(1 << bit, IC0_WAKESET);
> au_sync();
> }
>

> Index: linux-2.6/arch/mips/bcm63xx/irq.c
> ===================================================================
> --- linux-2.6.orig/arch/mips/bcm63xx/irq.c
> +++ linux-2.6/arch/mips/bcm63xx/irq.c
> @@ -75,8 +75,9 @@ asmlinkage void plat_irq_dispatch(void)
> * internal IRQs operations: only mask/unmask on PERF irq mask
> * register.
> */
> -static inline void bcm63xx_internal_irq_mask(unsigned int irq)
> +static inline void bcm63xx_internal_irq_mask(struct irq_desc *desc)
> {
> + unsigned int irq = desc->irq;
> u32 mask;
>
> irq -= IRQ_INTERNAL_BASE;
> @@ -84,9 +85,15 @@ static inline void bcm63xx_internal_irq_
> mask &= ~(1 << irq);
> bcm_perf_writel(mask, PERF_IRQMASK_REG);
> }
> +static void
> +bcm63xx_internal_irq_mask_desc(struct irq_desc *desc)
> +{
> + bcm63xx_internal_irq_mask(desc);
> +}

You have converted bcm63xx_internal_irq_mask making bcm63xx_internal_irq_mask_desc
unnecessary.

> @@ -213,8 +225,8 @@ static struct irq_chip bcm63xx_internal_
> .startup = bcm63xx_internal_irq_startup,
> .shutdown = bcm63xx_internal_irq_mask,
>
> - .mask = bcm63xx_internal_irq_mask,
> - .mask_ack = bcm63xx_internal_irq_mask,
> + .mask = bcm63xx_internal_irq_mask_desc,
> + .mask_ack = bcm63xx_internal_irq_mask_desc,
> .unmask = bcm63xx_internal_irq_unmask,
> };

These changes are also unnecessary.

> Index: linux-2.6/arch/mips/sni/pcimt.c
> ===================================================================
> --- linux-2.6.orig/arch/mips/sni/pcimt.c
> +++ linux-2.6/arch/mips/sni/pcimt.c

> -static void end_pcimt_irq(unsigned int irq)
> -{
> - if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
> - enable_pcimt_irq(irq);
> +static void end_pcimt_irq(struct irq_desc *desc)
> +
> + if (!(desc->status & (IRQ_DISABLED|IRQ_INPROGRESS)))
> + enable_pcimt_irq(desc);
> }

You have deleted the starting brace of the function....

> Index: linux-2.6/arch/powerpc/platforms/cell/axon_msi.c
> ===================================================================
> --- linux-2.6.orig/arch/powerpc/platforms/cell/axon_msi.c
> +++ linux-2.6/arch/powerpc/platforms/cell/axon_msi.c
> @@ -308,10 +308,15 @@ static void axon_msi_teardown_msi_irqs(s
> }
> }
>
> +static void axon_unmask_msi_irq(struct irq_desc *desc)
> +{
> + unmask_msi_irq(desc);
> +}
> +
> static struct irq_chip msic_irq_chip = {
> .mask = mask_msi_irq,
> .unmask = unmask_msi_irq,
> - .shutdown = unmask_msi_irq,
> + .shutdown = axon_unmask_msi_irq,
> .name = "AXON-MSI",
> };

This pair of changes is unnecessary.


> Index: linux-2.6/arch/powerpc/sysdev/mpic_u3msi.c
> ===================================================================
> --- linux-2.6.orig/arch/powerpc/sysdev/mpic_u3msi.c
> +++ linux-2.6/arch/powerpc/sysdev/mpic_u3msi.c
> @@ -23,20 +23,25 @@
> /* A bit ugly, can we get this from the pci_dev somehow? */
> static struct mpic *msi_mpic;
>
> -static void mpic_u3msi_mask_irq(unsigned int irq)
> +static void mpic_u3msi_mask_irq(struct irq_desc *desc)
> {
> - mask_msi_irq(irq);
> - mpic_mask_irq(irq);
> + mask_msi_irq(desc);
> + mpic_mask_irq(desc);
> }
>
> -static void mpic_u3msi_unmask_irq(unsigned int irq)
> +static void mpic_u3msi_shutdown_irq(struct irq_desc *desc)
> {
> - mpic_unmask_irq(irq);
> - unmask_msi_irq(irq);
> + mpic_u3msi_mask_irq(desc);
> +}
> +
> +static void mpic_u3msi_unmask_irq(struct irq_desc *desc)
> +{
> + mpic_unmask_irq(desc);
> + unmask_msi_irq(desc);
> }
>
> static struct irq_chip mpic_u3msi_chip = {
> - .shutdown = mpic_u3msi_mask_irq,
> + .shutdown = mpic_u3msi_shutdown_irq,
> .mask = mpic_u3msi_mask_irq,
> .unmask = mpic_u3msi_unmask_irq,
> .eoi = mpic_end_irq,

This change to add a new mpic_u3msi_shutdow_irq appears harmless, but
it is confusing and unnecessary.


> Index: linux-2.6/arch/sparc/kernel/pci_msi.c
> ===================================================================
> --- linux-2.6.orig/arch/sparc/kernel/pci_msi.c
> +++ linux-2.6/arch/sparc/kernel/pci_msi.c
> @@ -111,12 +111,21 @@ static void free_msi(struct pci_pbm_info
> clear_bit(msi_num, pbm->msi_bitmap);
> }
>
> +static void sparc64_enable_msi_irq(struct irq_desc *desc)
> +{
> + unmask_msi_irq(desc);
> +}
> +static void sparc64_diable_msi_irq(struct irq_desc *desc)
> +{
> + mask_msi_irq(desc);
> +}
> +
> static struct irq_chip msi_irq = {
> .name = "PCI-MSI",
> .mask = mask_msi_irq,
> .unmask = unmask_msi_irq,
> - .enable = unmask_msi_irq,
> - .disable = mask_msi_irq,
> + .enable = sparc64_enable_msi_irq,
> + .disable = sparc64_disable_msi_irq,
> /* XXX affinity XXX */
> };

Ouch! this hunk is unnecessary.

> Index: linux-2.6/drivers/xen/events.c
> ===================================================================
> --- linux-2.6.orig/drivers/xen/events.c
> +++ linux-2.6/drivers/xen/events.c
> @@ -748,35 +748,46 @@ int resend_irq_on_evtchn(unsigned int ir
> return 1;
> }
>
> -static void enable_dynirq(unsigned int irq)
> +static void enable_dynirq(struct irq_desc *desc)
> {
> - int evtchn = evtchn_from_irq(irq);
> + int evtchn = evtchn_from_irq(desc->irq);
>
> if (VALID_EVTCHN(evtchn))
> unmask_evtchn(evtchn);
> }
>
> -static void disable_dynirq(unsigned int irq)
> +static void unmask_dynirq(struct irq_desc *desc)
> {
> - int evtchn = evtchn_from_irq(irq);
> + enable_dynirq(desc);
> +}
> +

Introducing disable_dynirq, and mask_dynirq for xen is unnecessary.

> +static void disable_dynirq(struct irq_desc *desc)
> +{
> + int evtchn = evtchn_from_irq(desc->irq);
>
> if (VALID_EVTCHN(evtchn))
> mask_evtchn(evtchn);
> }
>
> -static void ack_dynirq(unsigned int irq)
> +static void mask_dynirq(struct irq_desc *desc)
> {
> - int evtchn = evtchn_from_irq(irq);
> + disable_dynirq(desc);
> +}
> +
> +static void ack_dynirq(struct irq_desc *desc)
> +{
> + int evtchn = evtchn_from_irq(desc->irq);
>
> - move_native_irq(irq);
> + move_native_irq(desc);
>
> if (VALID_EVTCHN(evtchn))
> clear_evtchn(evtchn);
> }
>
> -static int retrigger_dynirq(unsigned int irq)
> +static int retrigger_dynirq(struct irq_desc *desc)
> {
> - int evtchn = evtchn_from_irq(irq);
> + int evtchn = evtchn_from_irq(desc->irq);
> struct shared_info *sh = HYPERVISOR_shared_info;
> int ret = 0;
>
> @@ -924,10 +935,11 @@ static struct irq_chip xen_dynamic_chip
> .name = "xen-dyn",
>
> .disable = disable_dynirq,
> - .mask = disable_dynirq,
> - .unmask = enable_dynirq,
>
> + .mask = mask_dynirq,
> + .unmask = unmask_dynirq,
> .ack = ack_dynirq,
> +
> .set_affinity = set_affinity_irq,
> .retrigger = retrigger_dynirq,
> };


> Index: linux-2.6/include/linux/htirq.h
> ===================================================================
> --- linux-2.6.orig/include/linux/htirq.h
> +++ linux-2.6/include/linux/htirq.h
> @@ -7,16 +7,17 @@ struct ht_irq_msg {
> };
>
> /* Helper functions.. */
> -void fetch_ht_irq_msg(unsigned int irq, struct ht_irq_msg *msg);
> -void write_ht_irq_msg(unsigned int irq, struct ht_irq_msg *msg);
> -void mask_ht_irq(unsigned int irq);
> -void unmask_ht_irq(unsigned int irq);
> +struct irq_desc;
> +void fetch_ht_irq_msg(struct irq_desc *desc, struct ht_irq_msg *msg);
> +void write_ht_irq_msg(struct irq_desc *desc, struct ht_irq_msg *msg);
> +void mask_ht_irq(struct irq_desc *);
> +void unmask_ht_irq(struct irq_desc *);
>
> /* The arch hook for getting things started */
> int arch_setup_ht_irq(unsigned int irq, struct pci_dev *dev);
>
> /* For drivers of buggy hardware */
> -typedef void (ht_irq_update_t)(struct pci_dev *dev, int irq,
> +typedef void (ht_irq_update_t)(struct pci_dev *dev, struct irq_desc *desc,
> struct ht_irq_msg *msg);

The corresponding update to drivers/infiniband/hw/ipath/ipath_iba6110.c
is missing from your patch.

> int __ht_create_irq(struct pci_dev *dev, int idx, ht_irq_update_t *update);

> Index: linux-2.6/kernel/irq/chip.c
> ===================================================================
> --- linux-2.6.orig/kernel/irq/chip.c
> +++ linux-2.6/kernel/irq/chip.c
> @@ -131,7 +131,7 @@ int set_irq_chip(unsigned int irq, struc
> unsigned long flags;
>
> if (!desc) {
> - WARN(1, KERN_ERR "Trying to install chip for IRQ%d\n", irq);
> + WARN(1, KERN_ERR "Trying to install chip for IRQ\n");
> return -EINVAL;

We still have an irq value here so this change is wrong.

> @@ -657,7 +651,7 @@ __set_irq_handler(unsigned int irq, irq_
>
> if (!desc) {
> printk(KERN_ERR
> - "Trying to install type control for IRQ%d\n", irq);
> + "Trying to install type control for IRQ\n");

Again we still have an irq value here, so we should not remove it from
the printk.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/