irq, fs/proc: replace loop with nr_irqs for proc/stat
Replace another nr_irqs loop to avoid the allocation of all sparse
irq entries - use for_each_irq_desc instead.
v2: make sure arch without GENERIC_HARDIRQS works too
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/fs/proc/proc_misc.c b/fs/proc/proc_misc.c
index aa069ac..c3cbabe8 100644
--- a/fs/proc/proc_misc.c
+++ b/fs/proc/proc_misc.c
@@ -30,6 +30,7 @@
#include <linux/mm.h>
#include <linux/mmzone.h>
#include <linux/pagemap.h>
+#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/swap.h>
#include <linux/slab.h>
@@ -501,17 +502,16 @@
static int show_stat(struct seq_file *p, void *v)
{
- int i;
+ int i, j;
unsigned long jif;
cputime64_t user, nice, system, idle, iowait, irq, softirq, steal;
cputime64_t guest;
u64 sum = 0;
struct timespec boottime;
- unsigned int *per_irq_sum;
-
- per_irq_sum = kzalloc(sizeof(unsigned int)*nr_irqs, GFP_KERNEL);
- if (!per_irq_sum)
- return -ENOMEM;
+ unsigned int per_irq_sum;
+#ifdef CONFIG_GENERIC_HARDIRQS
+ struct irq_desc *desc;
+#endif
user = nice = system = idle = iowait =
irq = softirq = steal = cputime64_zero;
@@ -520,8 +520,6 @@
jif = boottime.tv_sec;
for_each_possible_cpu(i) {
- int j;
-
user = cputime64_add(user, kstat_cpu(i).cpustat.user);
nice = cputime64_add(nice, kstat_cpu(i).cpustat.nice);
system = cputime64_add(system, kstat_cpu(i).cpustat.system);
@@ -531,10 +529,12 @@
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 (j = 0; j < nr_irqs; j++) {
- unsigned int temp = kstat_irqs_cpu(j, i);
+ for_each_irq_desc(j, desc)
+ {
+ unsigned int temp;
+
+ temp = kstat_irqs_cpu(j, i);
sum += temp;
- per_irq_sum[j] += temp;
}
sum += arch_irq_stat_cpu(i);
}
@@ -577,8 +577,23 @@
}
seq_printf(p, "intr %llu", (unsigned long long)sum);
- for (i = 0; i < nr_irqs; i++)
- seq_printf(p, " %u", per_irq_sum[i]);
+ /* sum again ? it could be updated? */
+ for_each_irq_desc(j, desc)
+ {
+ per_irq_sum = 0;
+ for_each_possible_cpu(i) {
+ unsigned int temp;
+
+ temp = kstat_irqs_cpu(j, i);
+ per_irq_sum += temp;
+ }
+
+#ifdef CONFIG_HAVE_SPARSE_IRQ
+ seq_printf(p, " %u:%u", j, per_irq_sum);
+#else
+ seq_printf(p, " %u", per_irq_sum);
+#endif
+ }
seq_printf(p,
"\nctxt %llu\n"
@@ -592,7 +607,6 @@
nr_running(),
nr_iowait());
- kfree(per_irq_sum);
return 0;
}
diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index 5118038..d4039a0 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -17,6 +17,11 @@
extern int nr_irqs;
+#ifndef CONFIG_GENERIC_HARDIRQS
+#define for_each_irq_desc(irq, desc) \
+ for (irq = 0; irq < nr_irqs; irq++)
+#endif
+
/*
* These correspond to the IORESOURCE_IRQ_* defines in
* linux/ioport.h to select the interrupt line behaviour. When