Commit c7fb03a4 authored by Yinghai Lu's avatar Yinghai Lu Committed by Ingo Molnar
Browse files

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: default avatarYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 2c6927a3

fs/proc/proc_misc.c

+28 −14
Original line number Diff line number Diff line
@@ -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 const struct file_operations proc_vmalloc_operations = { 


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 @@ static int show_stat(struct seq_file *p, void *v) 
	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 @@ 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 (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 @@ static int show_stat(struct seq_file *p, void *v) 
	}

	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 @@ static int show_stat(struct seq_file *p, void *v) 
		nr_running(),

		nr_iowait());



	kfree(per_irq_sum);

	return 0;

}

include/linux/interrupt.h

+5 −0
Original line number Diff line number Diff line
@@ -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