Re: [PATCH v5 06/27] irq_domain/powerpc: eliminate irq_map; use irq_alloc_desc() instead

Grant Likely
2012-04-04T15:42:28Z

On Tue, 03 Apr 2012 14:11:12 +0200, Andreas Schwab <schwab@linux-m68k.org> wrote:
> Grant Likely <grant.likely@secretlab.ca> writes:
>
> > Can you dump out /debug/powerpc/virq_mapping from both before and
> > after the irq_map patch is applied?
>
> before:
> virq hwirq chip name chip data host name
> 16 0x00000 MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 21 0x00001 MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 24 0x00002 MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 25 0x00019 MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 26 0x0001a MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 27 0x0001b MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 28 0x0001c MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 29 0x0003d MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 30 0x0001e MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 31 0x0003c MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 39 0x00027 MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 40 0x00028 MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 41 0x00029 MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 42 0x0002a MPIC 2 0xc00000017a011000 /u3@0,f8000000/mpic@f8040000
> 47 0x0002f MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 59 0x000fb MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 60 0x000fc MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 61 0x000fd MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 62 0x000fe MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 63 0x0003f MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
>
> after:
> virq hwirq chip name chip data host name
> 16 0x00000 MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 21 0x00001 MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 24 0x00002 MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 25 0x00019 MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 26 0x0001a MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 27 0x0001b MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 28 0x0001c MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 30 0x0001e MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 39 0x00027 MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 40 0x00028 MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 41 0x00029 MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 42 0x0002a MPIC 2 0xc00000017a011000 /u3@0,f8000000/mpic@f8040000
> 47 0x0002f MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 59 0x000fb MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 60 0x000fc MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 61 0x000fd MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 62 0x000fe MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 63 0x0003f MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 64 0x0003d MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
> 65 0x0003c MPIC 1 0xc00000017a010000 /ht@0,f2000000/pci@1/mac-io@7/mpic@40000
>
> But I have NR_IRQS=64. Bounds checking missing? Irqs 64/65 are related
> to the sound chip (headphone-detect and line-out-detect).

I bet it is NR_IRQS related. You have SPARSE_IRQ enabled, which means
the maximum number of irq_descs is IRQ_BITMAP_BITS (NR_IRQS + 8192).
The old powerpc code was strictly limited to NR_IRQS, but the new code
uses irq_alloc_descs() which isn't. Yet I can see places in the
powerpc code that depends specifically on the value of NR_IRQS. The
for_each_irq() macro for instance. I think all the users there can be
switched to using for_each_irq_desc().

Can you attach console output logs for each of configs above and also
with NR_IRQS=128? That might give me some clues as to which specific
code is causing the issues. Also, as a quick test, try changing
for_each_irq_desc() to use "nr_irqs" instead of "NR_IRQS". nr_irqs is
kept up to date with the real maximum number of irqs allocated in the
system:

diff --git a/arch/powerpc/include/asm/irq.h b/arch/powerpc/include/asm/irq.h
index cf417e51..9edf499 100644
--- a/arch/powerpc/include/asm/irq.h
+++ b/arch/powerpc/include/asm/irq.h
@@ -20,7 +20,7 @@

/* Define a way to iterate across irqs. */
#define for_each_irq(i) \
- for ((i) = 0; (i) < NR_IRQS; ++(i))
+ for ((i) = 0; (i) < nr_irqs; ++(i))

extern atomic_t ppc_n_lost_interrupts;

g.

>
> When reconfiguring with NR_IRQS=128 interrupts are working again, but I
> still see a lot of spurious interrupts, and the X server is still broken
> (no input works, but I still don't know whether that is an unrelated
> bug).
>
> This is a sample of /proc/interrupts from 3.3 (with NR_IRQS=64):
> CPU0 CPU1
> 16: 2039 6070 MPIC 1 Level sata_svw
> 21: 0 0 MPIC 1 Edge i2sbus: i2s-a (tx)
> 22: 12 20 MPIC 1 Level
> 23: 14 18 MPIC 1 Level
> 24: 0 0 MPIC 1 Edge i2sbus: i2s-a (rx)
> 25: 3 0 MPIC 1 Level VIA-PMU
> 26: 16 62 MPIC 1 Level keywest i2c
> 27: 0 1 MPIC 1 Level ohci_hcd:usb2
> 28: 0 1 MPIC 1 Level ohci_hcd:usb3
> 29: 0 0 MPIC 1 Edge headphone-detect
> 30: 0 0 MPIC 1 Level i2sbus: i2s-a (control)
> 31: 0 0 MPIC 1 Edge line-output-detect
> 39: 22 64 MPIC 1 Level pata-pci-macio
> 40: 0 2 MPIC 1 Level firewire_ohci
> 41: 52 147 MPIC 1 Level eth0
> 42: 1732 5053 MPIC 2 Level keywest i2c
> 47: 0 0 MPIC 1 Level GPIO1 ADB
> 59: 0 0 MPIC 1 Edge ipi call function
> 60: 2064 1940 MPIC 1 Edge ipi reschedule
> 61: 3406 945 MPIC 1 Edge ipi call function single
> 62: 0 0 MPIC 1 Edge ipi debugger
> 63: 39 91 MPIC 1 Level ehci_hcd:usb1, ohci_hcd:usb4, ohci_hcd:usb5
> LOC: 3503 3719 Local timer interrupts
> SPU: 2 0 Spurious interrupts
> CNT: 0 0 Performance monitoring interrupts
> MCE: 0 0 Machine check exceptions
>
> This is a sample of /proc/interrupts from 3.4-rc1 (with NR_IRQS=128):
> CPU0 CPU1
> 16: 2603 7596 MPIC 1 Level sata_svw
> 21: 1 0 MPIC 1 Edge i2sbus: i2s-a (tx)
> 22: 13 19 MPIC 1 Level
> 23: 8 24 MPIC 1 Level
> 24: 0 1 MPIC 1 Edge i2sbus: i2s-a (rx)
> 25: 2 1 MPIC 1 Level VIA-PMU
> 26: 21 57 MPIC 1 Level keywest i2c
> 27: 0 1 MPIC 1 Level ohci_hcd:usb2
> 28: 0 1 MPIC 1 Level ohci_hcd:usb3
> 30: 0 0 MPIC 1 Level i2sbus: i2s-a (control)
> 39: 39 131 MPIC 1 Level pata-pci-macio
> 40: 2 2 MPIC 1 Level firewire_ohci
> 41: 93 268 MPIC 1 Level eth0
> 42: 8569 24140 MPIC 2 Level keywest i2c
> 47: 0 0 MPIC 1 Level GPIO1 ADB
> 60: 1 0 MPIC 1 Edge line-output-detect
> 61: 1 0 MPIC 1 Edge headphone-detect
> 63: 153 502 MPIC 1 Level ehci_hcd:usb1, ohci_hcd:usb4, ohci_hcd:usb5
> 123: 0 0 MPIC 1 Edge ipi call function
> 124: 1978 2349 MPIC 1 Edge ipi reschedule
> 125: 2356 1816 MPIC 1 Edge ipi call function single
> 126: 0 0 MPIC 1 Edge ipi debugger
> LOC: 4417 7985 Local timer interrupts
> SPU: 9586 25811 Spurious interrupts
> CNT: 0 0 Performance monitoring interrupts
> MCE: 0 0 Machine check exceptions
>
> Andreas.
>
> --
> Andreas Schwab, schwab@linux-m68k.org
> GPG Key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5
> "And now for something completely different."

--
Grant Likely, B.Sc, P.Eng.
Secret Lab Technologies,Ltd.