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| author | Thomas Gleixner <tglx@linutronix.de> | 2017-06-20 01:37:38 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2017-06-22 18:21:20 +0200 |
| commit | 0d3f54257dc300f2db480d6a46b34bdb87f18c1b (patch) | |
| tree | f989dcf40159e1d77ca900dc6f9d42989df403e4 /kernel/irq/irqdesc.c | |
| parent | genirq/proc: Replace ever repeating type cast (diff) | |
| download | linux-0d3f54257dc300f2db480d6a46b34bdb87f18c1b.tar.xz linux-0d3f54257dc300f2db480d6a46b34bdb87f18c1b.zip | |
genirq: Introduce effective affinity mask
There is currently no way to evaluate the effective affinity mask of a
given interrupt. Many irq chips allow only a single target CPU or a subset
of CPUs in the affinity mask.
Updating the mask at the time of setting the affinity to the subset would
be counterproductive because information for cpu hotplug about assigned
interrupt affinities gets lost. On CPU hotplug it's also pointless to force
migrate an interrupt, which is not targeted at the CPU effectively. But
currently the information is not available.
Provide a seperate mask to be updated by the irq_chip->irq_set_affinity()
implementations. Implement the read only proc files so the user can see the
effective mask as well w/o trying to deduce it from /proc/interrupts.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Christoph Hellwig <hch@lst.de>
Link: http://lkml.kernel.org/r/20170619235446.247834245@linutronix.de
Diffstat (limited to 'kernel/irq/irqdesc.c')
| -rw-r--r-- | kernel/irq/irqdesc.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c index 48d4f0365e52..35a95fadcfda 100644 --- a/kernel/irq/irqdesc.c +++ b/kernel/irq/irqdesc.c @@ -60,8 +60,19 @@ static int alloc_masks(struct irq_desc *desc, int node) GFP_KERNEL, node)) return -ENOMEM; +#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK + if (!zalloc_cpumask_var_node(&desc->irq_common_data.effective_affinity, + GFP_KERNEL, node)) { + free_cpumask_var(desc->irq_common_data.affinity); + return -ENOMEM; + } +#endif + #ifdef CONFIG_GENERIC_PENDING_IRQ if (!zalloc_cpumask_var_node(&desc->pending_mask, GFP_KERNEL, node)) { +#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK + free_cpumask_var(desc->irq_common_data.effective_affinity); +#endif free_cpumask_var(desc->irq_common_data.affinity); return -ENOMEM; } @@ -324,6 +335,9 @@ static void free_masks(struct irq_desc *desc) free_cpumask_var(desc->pending_mask); #endif free_cpumask_var(desc->irq_common_data.affinity); +#ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK + free_cpumask_var(desc->irq_common_data.effective_affinity); +#endif } #else static inline void free_masks(struct irq_desc *desc) { } |