From 0b8f1efad30bd58f89961b82dfe68b9edf8fd2ac Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Fri, 5 Dec 2008 18:58:31 -0800 Subject: sparse irq_desc[] array: core kernel and x86 changes Impact: new feature Problem on distro kernels: irq_desc[NR_IRQS] takes megabytes of RAM with NR_CPUS set to large values. The goal is to be able to scale up to much larger NR_IRQS value without impacting the (important) common case. To solve this, we generalize irq_desc[NR_IRQS] to an (optional) array of irq_desc pointers. When CONFIG_SPARSE_IRQ=y is used, we use kzalloc_node to get irq_desc, this also makes the IRQ descriptors NUMA-local (to the site that calls request_irq()). This gets rid of the irq_cfg[] static array on x86 as well: irq_cfg now uses desc->chip_data for x86 to store irq_cfg. Signed-off-by: Yinghai Lu Signed-off-by: Ingo Molnar --- fs/proc/stat.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) (limited to 'fs/proc') diff --git a/fs/proc/stat.c b/fs/proc/stat.c index 81904f07679d..a13431ab7c65 100644 --- a/fs/proc/stat.c +++ b/fs/proc/stat.c @@ -27,6 +27,7 @@ static int show_stat(struct seq_file *p, void *v) u64 sum = 0; struct timespec boottime; unsigned int per_irq_sum; + struct irq_desc *desc; user = nice = system = idle = iowait = irq = softirq = steal = cputime64_zero; @@ -44,10 +45,11 @@ static int show_stat(struct seq_file *p, void *v) softirq = cputime64_add(softirq, kstat_cpu(i).cpustat.softirq); steal = cputime64_add(steal, kstat_cpu(i).cpustat.steal); guest = cputime64_add(guest, kstat_cpu(i).cpustat.guest); - - for_each_irq_nr(j) + for_each_irq_desc(j, desc) { + if (!desc) + continue; sum += kstat_irqs_cpu(j, i); - + } sum += arch_irq_stat_cpu(i); } sum += arch_irq_stat(); @@ -90,11 +92,14 @@ static int show_stat(struct seq_file *p, void *v) seq_printf(p, "intr %llu", (unsigned long long)sum); /* sum again ? it could be updated? */ - for_each_irq_nr(j) { + for (j = 0; j < NR_IRQS; j++) { + desc = irq_to_desc(j); per_irq_sum = 0; - for_each_possible_cpu(i) - per_irq_sum += kstat_irqs_cpu(j, i); + if (desc) { + for_each_possible_cpu(i) + per_irq_sum += kstat_irqs_cpu(j, i); + } seq_printf(p, " %u", per_irq_sum); } -- cgit From 240d367b4e6c6e3c5075e034db14dba60a6f5fa7 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Mon, 8 Dec 2008 14:06:17 -0800 Subject: sparseirq: fix Alpha build failure Impact: build fix on Alpha -tip testing found this build failure on the Alpha defconfig: /home/mingo/tip/fs/proc/stat.c: In function 'show_stat': /home/mingo/tip/fs/proc/stat.c:48: error: implicit declaration of function 'for_each_irq_desc' /home/mingo/tip/fs/proc/stat.c:48: error: expected ';' before '{' token can not use irq_desc() in stat.c on older architectures. Signed-off-by: Yinghai Lu Signed-off-by: Ingo Molnar --- fs/proc/stat.c | 20 +++++++++++++------- include/linux/irq.h | 9 --------- include/linux/irqnr.h | 19 ++++++++++++++++--- 3 files changed, 29 insertions(+), 19 deletions(-) (limited to 'fs/proc') diff --git a/fs/proc/stat.c b/fs/proc/stat.c index a13431ab7c65..3cb9492801c0 100644 --- a/fs/proc/stat.c +++ b/fs/proc/stat.c @@ -45,9 +45,12 @@ static int show_stat(struct seq_file *p, void *v) softirq = cputime64_add(softirq, kstat_cpu(i).cpustat.softirq); steal = cputime64_add(steal, kstat_cpu(i).cpustat.steal); guest = cputime64_add(guest, kstat_cpu(i).cpustat.guest); - for_each_irq_desc(j, desc) { + for_each_irq_nr(j) { +#ifdef CONFIG_SPARSE_IRQ + desc = irq_to_desc(j); if (!desc) continue; +#endif sum += kstat_irqs_cpu(j, i); } sum += arch_irq_stat_cpu(i); @@ -92,14 +95,17 @@ static int show_stat(struct seq_file *p, void *v) seq_printf(p, "intr %llu", (unsigned long long)sum); /* sum again ? it could be updated? */ - for (j = 0; j < NR_IRQS; j++) { - desc = irq_to_desc(j); + for_each_irq_nr(j) { per_irq_sum = 0; - - if (desc) { - for_each_possible_cpu(i) - per_irq_sum += kstat_irqs_cpu(j, i); +#ifdef CONFIG_SPARSE_IRQ + desc = irq_to_desc(j); + if (!desc) { + seq_printf(p, " %u", per_irq_sum); + continue; } +#endif + for_each_possible_cpu(i) + per_irq_sum += kstat_irqs_cpu(j, i); seq_printf(p, " %u", per_irq_sum); } diff --git a/include/linux/irq.h b/include/linux/irq.h index 63b00439d4d2..b5749db3e5a1 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -198,7 +198,6 @@ extern void arch_init_copy_chip_data(struct irq_desc *old_desc, extern void arch_free_chip_data(struct irq_desc *old_desc, struct irq_desc *desc); #ifndef CONFIG_SPARSE_IRQ - extern struct irq_desc irq_desc[NR_IRQS]; static inline struct irq_desc *irq_to_desc(unsigned int irq) @@ -210,14 +209,6 @@ static inline struct irq_desc *irq_to_desc_alloc_cpu(unsigned int irq, int cpu) return irq_to_desc(irq); } -#ifdef CONFIG_GENERIC_HARDIRQS -# define for_each_irq_desc(irq, desc) \ - for (irq = 0, desc = irq_desc; irq < nr_irqs; irq++, desc++) -# define for_each_irq_desc_reverse(irq, desc) \ - for (irq = nr_irqs - 1, desc = irq_desc + (nr_irqs - 1); \ - irq >= 0; irq--, desc--) -#endif - #else extern struct irq_desc *irq_to_desc(unsigned int irq); diff --git a/include/linux/irqnr.h b/include/linux/irqnr.h index 7a299e989f8b..13754f813589 100644 --- a/include/linux/irqnr.h +++ b/include/linux/irqnr.h @@ -8,9 +8,22 @@ # define for_each_irq_desc(irq, desc) \ for (irq = 0; irq < nr_irqs; irq++) -static inline early_sparse_irq_init(void) -{ -} +# define for_each_irq_desc_reverse(irq, desc) \ + for (irq = nr_irqs - 1; irq >= 0; irq--) +#else +#ifndef CONFIG_SPARSE_IRQ + +struct irq_desc; +extern int nr_irqs; +# define for_each_irq_desc(irq, desc) \ + for (irq = 0, desc = irq_desc; irq < nr_irqs; irq++, desc++) +# define for_each_irq_desc_reverse(irq, desc) \ + for (irq = nr_irqs - 1, desc = irq_desc + (nr_irqs - 1); \ + irq >= 0; irq--, desc--) #endif +#endif + +#define for_each_irq_nr(irq) \ + for (irq = 0; irq < nr_irqs; irq++) #endif -- cgit