From 51906e779f2b13b38f8153774c4c7163d412ffd9 Mon Sep 17 00:00:00 2001 From: Alexander Gordeev Date: Mon, 19 Nov 2012 16:01:29 +0100 Subject: x86/MSI: Support multiple MSIs in presense of IRQ remapping The MSI specification has several constraints in comparison with MSI-X, most notable of them is the inability to configure MSIs independently. As a result, it is impossible to dispatch interrupts from different queues to different CPUs. This is largely devalues the support of multiple MSIs in SMP systems. Also, a necessity to allocate a contiguous block of vector numbers for devices capable of multiple MSIs might cause a considerable pressure on x86 interrupt vector allocator and could lead to fragmentation of the interrupt vectors space. This patch overcomes both drawbacks in presense of IRQ remapping and lets devices take advantage of multiple queues and per-IRQ affinity assignments. Signed-off-by: Alexander Gordeev Cc: Bjorn Helgaas Cc: Suresh Siddha Cc: Yinghai Lu Cc: Matthew Wilcox Cc: Jeff Garzik Cc: Linus Torvalds Cc: Andrew Morton Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/c8bd86ff56b5fc118257436768aaa04489ac0a4c.1353324359.git.agordeev@redhat.com Signed-off-by: Ingo Molnar --- include/linux/irq.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include/linux/irq.h') diff --git a/include/linux/irq.h b/include/linux/irq.h index fdf2c4a238cc..1eab99111e94 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -528,6 +528,8 @@ extern int irq_set_handler_data(unsigned int irq, void *data); extern int irq_set_chip_data(unsigned int irq, void *data); extern int irq_set_irq_type(unsigned int irq, unsigned int type); extern int irq_set_msi_desc(unsigned int irq, struct msi_desc *entry); +extern int irq_set_msi_desc_off(unsigned int irq_base, unsigned int irq_offset, + struct msi_desc *entry); extern struct irq_data *irq_get_irq_data(unsigned int irq); static inline struct irq_chip *irq_get_chip(unsigned int irq) @@ -590,6 +592,9 @@ int __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node, #define irq_alloc_desc_from(from, node) \ irq_alloc_descs(-1, from, 1, node) +#define irq_alloc_descs_from(from, cnt, node) \ + irq_alloc_descs(-1, from, cnt, node) + void irq_free_descs(unsigned int irq, unsigned int cnt); int irq_reserve_irqs(unsigned int from, unsigned int cnt); -- cgit v1.2.3 From 5afba62cc8a16716508605e02c1b02ee5f969184 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Wed, 26 Sep 2012 12:44:38 +0200 Subject: x86, msi: Use IRQ remapping specific setup_msi_irqs routine Use seperate routines to setup MSI IRQs for both irq_remapping_enabled cases. Signed-off-by: Joerg Roedel Acked-by: Sebastian Andrzej Siewior Reviewed-by: Konrad Rzeszutek Wilk --- include/linux/irq.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux/irq.h') diff --git a/include/linux/irq.h b/include/linux/irq.h index 1eab99111e94..bc4e06611958 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -509,8 +509,11 @@ static inline void irq_set_percpu_devid_flags(unsigned int irq) /* Handle dynamic irq creation and destruction */ extern unsigned int create_irq_nr(unsigned int irq_want, int node); +extern unsigned int __create_irqs(unsigned int from, unsigned int count, + int node); extern int create_irq(void); extern void destroy_irq(unsigned int irq); +extern void destroy_irqs(unsigned int irq, unsigned int count); /* * Dynamic irq helper functions. Obsolete. Use irq_alloc_desc* and -- cgit v1.2.3