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 v1.2.2 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 +++++++++++++------- 1 file changed, 13 insertions(+), 7 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); } -- cgit v1.2.2 From 13bd41bc227a48d6cf8992a3286bf6eba3c71a0c Mon Sep 17 00:00:00 2001 From: KOSAKI Motohiro Date: Tue, 16 Dec 2008 00:23:34 -0800 Subject: proc: enclose desc variable of show_stat() in CONFIG_SPARSE_IRQ Impact: restructure code to fix compiler warning commit 240d367b4e6c6e3c5075e034db14dba60a6f5fa7 moved desc usage point into #ifdef CONFIG_SPARSE_IRQ. Eliminate the desc variable, otherwise following warning happens: fs/proc/stat.c: In function 'show_stat': fs/proc/stat.c:31: warning: unused variable 'desc' [ akpm: cleaned up the patch to remove #ifdef ] Signed-off-by: KOSAKI Motohiro Signed-off-by: Andrew Morton Signed-off-by: Ingo Molnar --- fs/proc/stat.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) (limited to 'fs/proc') diff --git a/fs/proc/stat.c b/fs/proc/stat.c index 3cb9492801c0..3bb1cf1e7425 100644 --- a/fs/proc/stat.c +++ b/fs/proc/stat.c @@ -27,7 +27,6 @@ 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; @@ -47,8 +46,7 @@ static int show_stat(struct seq_file *p, void *v) guest = cputime64_add(guest, kstat_cpu(i).cpustat.guest); for_each_irq_nr(j) { #ifdef CONFIG_SPARSE_IRQ - desc = irq_to_desc(j); - if (!desc) + if (!irq_to_desc(j)) continue; #endif sum += kstat_irqs_cpu(j, i); @@ -98,8 +96,7 @@ static int show_stat(struct seq_file *p, void *v) for_each_irq_nr(j) { per_irq_sum = 0; #ifdef CONFIG_SPARSE_IRQ - desc = irq_to_desc(j); - if (!desc) { + if (!irq_to_desc(j)) { seq_printf(p, " %u", per_irq_sum); continue; } -- cgit v1.2.2