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| author | Ashok Raj <ashok.raj@intel.com> | 2005-09-06 15:16:15 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2005-09-07 16:57:15 -0700 |
| commit | 54d5d42404e7705cf3804593189e963350d470e5 (patch) | |
| tree | 7cf8a7fce163b19672193d8cf4ef6a7f6c131d9e /kernel/irq | |
| parent | f63ed39c578a2a2d067356a85ce7c28a7c795d8a (diff) | |
| download | linux-stable-54d5d42404e7705cf3804593189e963350d470e5.tar.gz linux-stable-54d5d42404e7705cf3804593189e963350d470e5.tar.bz2 linux-stable-54d5d42404e7705cf3804593189e963350d470e5.zip | |
[PATCH] x86/x86_64: deferred handling of writes to /proc/irqxx/smp_affinity
When handling writes to /proc/irq, current code is re-programming rte
entries directly. This is not recommended and could potentially cause
chipset's to lockup, or cause missing interrupts.
CONFIG_IRQ_BALANCE does this correctly, where it re-programs only when the
interrupt is pending. The same needs to be done for /proc/irq handling as well.
Otherwise user space irq balancers are really not doing the right thing.
- Changed pending_irq_balance_cpumask to pending_irq_migrate_cpumask for
lack of a generic name.
- added move_irq out of IRQ_BALANCE, and added this same to X86_64
- Added new proc handler for write, so we can do deferred write at irq
handling time.
- Display of /proc/irq/XX/smp_affinity used to display CPU_MASKALL, instead
it now shows only active cpu masks, or exactly what was set.
- Provided a common move_irq implementation, instead of duplicating
when using generic irq framework.
Tested on i386/x86_64 and ia64 with CONFIG_PCI_MSI turned on and off.
Tested UP builds as well.
MSI testing: tbd: I have cards, need to look for a x-over cable, although I
did test an earlier version of this patch. Will test in a couple days.
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Acked-by: Zwane Mwaikambo <zwane@holomorphy.com>
Grudgingly-acked-by: Andi Kleen <ak@muc.de>
Signed-off-by: Coywolf Qi Hunt <coywolf@lovecn.org>
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'kernel/irq')
| -rw-r--r-- | kernel/irq/manage.c | 4 | ||||
| -rw-r--r-- | kernel/irq/proc.c | 14 |
2 files changed, 16 insertions, 2 deletions
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index ac6700985705..1cfdb08ddf20 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -18,6 +18,10 @@ cpumask_t irq_affinity[NR_IRQS] = { [0 ... NR_IRQS-1] = CPU_MASK_ALL }; +#if defined (CONFIG_GENERIC_PENDING_IRQ) || defined (CONFIG_IRQBALANCE) +cpumask_t __cacheline_aligned pending_irq_cpumask[NR_IRQS]; +#endif + /** * synchronize_irq - wait for pending IRQ handlers (on other CPUs) * diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c index 85d08daa6600..f26e534c6585 100644 --- a/kernel/irq/proc.c +++ b/kernel/irq/proc.c @@ -19,12 +19,22 @@ static struct proc_dir_entry *root_irq_dir, *irq_dir[NR_IRQS]; */ static struct proc_dir_entry *smp_affinity_entry[NR_IRQS]; -void __attribute__((weak)) -proc_set_irq_affinity(unsigned int irq, cpumask_t mask_val) +#ifdef CONFIG_GENERIC_PENDING_IRQ +void proc_set_irq_affinity(unsigned int irq, cpumask_t mask_val) +{ + /* + * Save these away for later use. Re-progam when the + * interrupt is pending + */ + set_pending_irq(irq, mask_val); +} +#else +void proc_set_irq_affinity(unsigned int irq, cpumask_t mask_val) { irq_affinity[irq] = mask_val; irq_desc[irq].handler->set_affinity(irq, mask_val); } +#endif static int irq_affinity_read_proc(char *page, char **start, off_t off, int count, int *eof, void *data) |