Messages in this thread Patch in this message | | | From | "Eric W. Biederman" <> | Subject | [PATCH 20/25] irq: Generalize the check for HARDIRQ_BITS. | Date | Tue, 20 Jun 2006 16:28:33 -0600 |
| |
This patch adds support for systems that cannot receive every interrupt on a single cpu simultaneously, in the check to see if we have enough HARDIRQ_BITS.
MAX_HARDIRQS_PER_CPU becomes the count of the maximum number of hardare generated interrupts per cpu.
On architectures that support per cpu interrupt delivery this can be a significant space savings and scalability bonus.
This patch adds support for systems that cannot receive every interrupt on
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> --- include/asm-x86_64/hardirq.h | 3 +++ include/linux/hardirq.h | 7 ++++++- 2 files changed, 9 insertions(+), 1 deletions(-)
diff --git a/include/asm-x86_64/hardirq.h b/include/asm-x86_64/hardirq.h index 64a65ce..95d5e09 100644 --- a/include/asm-x86_64/hardirq.h +++ b/include/asm-x86_64/hardirq.h @@ -6,6 +6,9 @@ #include <linux/irq.h> #include <asm/pda.h> #include <asm/apic.h> +/* We can have at most NR_VECTORS irqs routed to a cpu at a time */ +#define MAX_HARDIRQS_PER_CPU NR_VECTORS + #define __ARCH_IRQ_STAT 1 #define local_softirq_pending() read_pda(__softirq_pending) diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h index ccabda7..f60b8c3 100644 --- a/include/linux/hardirq.h +++ b/include/linux/hardirq.h @@ -27,11 +27,16 @@ #define SOFTIRQ_BITS 8 #ifndef HARDIRQ_BITS #define HARDIRQ_BITS 12 + +#ifndef MAX_HARDIRQS_PER_CPU +#define MAX_HARDIRQS_PER_CPU NR_IRQS +#endif + /* * The hardirq mask has to be large enough to have space for potentially * all IRQ sources in the system nesting on a single CPU. */ -#if (1 << HARDIRQ_BITS) < NR_IRQS +#if (1 << HARDIRQ_BITS) < MAX_HARDIRQS_PER_CPU # error HARDIRQ_BITS is too low! #endif #endif -- 1.4.0.gc07e - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |