Commit Graph

5 Commits

Author SHA1 Message Date
Suresh Siddha 18374d89e5 x86, irq: Allow 0xff for /proc/irq/[n]/smp_affinity on an 8-cpu system
John Blackwood reported:
> on an older Dell PowerEdge 6650 system with 8 cpus (4 are hyper-threaded),
> and  32 bit (x86) kernel, once you change the irq smp_affinity of an irq
> to be less than all cpus in the system, you can never change really the
> irq smp_affinity back to be all cpus in the system (0xff) again,
> even though no error status is returned on the "/bin/echo ff >
> /proc/irq/[n]/smp_affinity" operation.
>
> This is due to that fact that BAD_APICID has the same value as
> all cpus (0xff) on 32bit kernels, and thus the value returned from
> set_desc_affinity() via the cpu_mask_to_apicid_and() function is treated
> as a failure in set_ioapic_affinity_irq_desc(), and no affinity changes
> are made.

set_desc_affinity() is already checking if the incoming cpu mask
intersects with the cpu online mask or not. So there is no need
for the apic op cpu_mask_to_apicid_and() to check again
and return BAD_APICID.

Remove the BAD_APICID return value from cpu_mask_to_apicid_and()
and also fix set_desc_affinity() to return -1 instead of using BAD_APICID
to represent error conditions (as cpu_mask_to_apicid_and() can return
logical or physical apicid values and BAD_APICID is really to represent
bad physical apic id).

Reported-by: John Blackwood <john.blackwood@ccur.com>
Root-caused-by: John Blackwood <john.blackwood@ccur.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1261103386.2535.409.camel@sbs-t61>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-12-17 22:03:06 -08:00
Dimitri Sivanich 9338ad6ffb x86, apic: Move SGI UV functionality out of generic IO-APIC code
Move UV specific functionality out of the generic IO-APIC code.

Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
LKML-Reference: <20091013203236.GD20543@sgi.com>
[ Cleaned up the code some more in their new places. ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-14 09:17:09 +02:00
Dimitri Sivanich 6c2c502910 x86: SGI UV: Fix irq affinity for hub based interrupts
This patch fixes handling of uv hub irq affinity.  IRQs with ALL or
NODE affinity can be routed to cpus other than their originally
assigned cpu.  Those with CPU affinity cannot be rerouted.

Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
LKML-Reference: <20090930160259.GA7822@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-14 09:17:01 +02:00
Ingo Molnar 37762b6ffb x86, UV: add uv_setup_irq() and uv_teardown_irq() functions, v3, fix
fix:

 arch/x86/kernel/uv_irq.c: In function 'uv_ack_apic':
 arch/x86/kernel/uv_irq.c:26: error: implicit declaration of function 'ack_APIC_irq'

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-16 16:53:13 +02:00
Dean Nelson 4173a0e737 x86, UV: add uv_setup_irq() and uv_teardown_irq() functions, v3
Provide a means for UV interrupt MMRs to be setup with the message to be sent
when an MSI is raised.

Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-16 16:53:12 +02:00