Now, Linux uses the irq_affinity_desc to convey information. As Kashyap and Sumit reported, in MSI/-x subsystem, the pre/post vectors may be used to some extra reply queues for performance.
https://marc.info/?l=linux-kernel&m=153543887027997&w=2 Their affinities are not NULL, but, they should be mapped as unmanaged interrupts. So, only transfering the irq affinity assignments is not enough. Add a new bit "is_managed" to convey the info in irq_affinity_desc and use it in alloc_descs(). Reported-by: Kashyap Desai <kashyap.de...@broadcom.com> Reported-by: Sumit Saxena <sumit.sax...@broadcom.com> Signed-off-by: Dou Liyang <douliya...@gmail.com> --- include/linux/interrupt.h | 1 + kernel/irq/affinity.c | 7 +++++++ kernel/irq/irqdesc.c | 9 +++++++-- 3 files changed, 15 insertions(+), 2 deletions(-) diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h index 71be303231e9..a12b3dbbc45e 100644 --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -263,6 +263,7 @@ struct irq_affinity { */ struct irq_affinity_desc { struct cpumask mask; + unsigned int is_managed : 1; }; #if defined(CONFIG_SMP) diff --git a/kernel/irq/affinity.c b/kernel/irq/affinity.c index 1562a36e7c0f..d122575ba1b4 100644 --- a/kernel/irq/affinity.c +++ b/kernel/irq/affinity.c @@ -289,6 +289,13 @@ irq_create_affinity_masks(int nvecs, const struct irq_affinity *affd) for (; curvec < nvecs; curvec++) cpumask_copy(&masks[curvec].mask, irq_default_affinity); + /* Setup complementary information */ + for (i = 0; i < nvecs; i++) { + if (i >= affd->pre_vectors && i < nvecs - affd->post_vectors) + masks[i].is_managed = 1; + else + masks[i].is_managed = 0; + } outnodemsk: free_node_to_cpumask(node_to_cpumask); return masks; diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c index f87fa2b9935a..6b0821c144c0 100644 --- a/kernel/irq/irqdesc.c +++ b/kernel/irq/irqdesc.c @@ -455,7 +455,7 @@ static int alloc_descs(unsigned int start, unsigned int cnt, int node, const struct irq_affinity_desc *cur_affinity= affinity; const struct cpumask *mask = NULL; struct irq_desc *desc; - unsigned int flags; + unsigned int flags = 0; int i; /* Validate affinity mask(s) */ @@ -468,11 +468,16 @@ static int alloc_descs(unsigned int start, unsigned int cnt, int node, } } - flags = affinity ? IRQD_AFFINITY_MANAGED | IRQD_MANAGED_SHUTDOWN : 0; mask = NULL; for (i = 0; i < cnt; i++) { if (affinity) { + if (affinity->is_managed) { + flags = IRQD_AFFINITY_MANAGED | + IRQD_MANAGED_SHUTDOWN; + } else { + flags = 0; + } mask = &affinity->mask; node = cpu_to_node(cpumask_first(mask)); affinity++; -- 2.17.2
