proc: export statistics for softirq to /proc
Export statistics for softirq in /proc/softirqs and /proc/stat.
1. /proc/softirqs
Implement /proc/softirqs which shows the number of softirq
for each CPU like /proc/interrupts.
2. /proc/stat
Add the "softirq" line to /proc/stat.
This line shows the number of softirq for all cpu.
The first column is the total of all softirqs and
each subsequent column is the total for particular softirq.
[kosaki.motohiro@jp.fujitsu.com: remove redundant for_each_possible_cpu() loop]
Signed-off-by: Keika Kobayashi <kobayashi.kk@ncos.nec.co.jp>
Reviewed-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index ebff3c1..fb7d649 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -283,6 +283,7 @@
rtc Real time clock
scsi SCSI info (see text)
slabinfo Slab pool info
+ softirqs softirq usage
stat Overall statistics
swaps Swap space utilization
sys See chapter 2
@@ -597,6 +598,25 @@
0xffffffffa0017000-0xffffffffa0022000 45056 sys_init_module+0xc27/0x1d00 ...
pages=10 vmalloc N0=10
+..............................................................................
+
+softirqs:
+
+Provides counts of softirq handlers serviced since boot time, for each cpu.
+
+> cat /proc/softirqs
+ CPU0 CPU1 CPU2 CPU3
+ HI: 0 0 0 0
+ TIMER: 27166 27120 27097 27034
+ NET_TX: 0 0 0 17
+ NET_RX: 42 0 0 39
+ BLOCK: 0 0 107 1121
+ TASKLET: 0 0 0 290
+ SCHED: 27035 26983 26971 26746
+ HRTIMER: 0 0 0 0
+ RCU: 1678 1769 2178 2250
+
+
1.3 IDE devices in /proc/ide
----------------------------
@@ -883,6 +903,7 @@
processes 2915
procs_running 1
procs_blocked 0
+ softirq 183433 0 21755 12 39 1137 231 21459 2263
The very first "cpu" line aggregates the numbers in all of the other "cpuN"
lines. These numbers identify the amount of time the CPU has spent performing
@@ -918,6 +939,11 @@
The "procs_blocked" line gives the number of processes currently blocked,
waiting for I/O to complete.
+The "softirq" line gives counts of softirqs serviced since boot time, for each
+of the possible system softirqs. The first column is the total of all
+softirqs serviced; each subsequent column is the total for that particular
+softirq.
+
1.9 Ext4 file system parameters
------------------------------
diff --git a/fs/proc/Makefile b/fs/proc/Makefile
index 63d9651..11a7b5c 100644
--- a/fs/proc/Makefile
+++ b/fs/proc/Makefile
@@ -18,6 +18,7 @@
proc-y += stat.o
proc-y += uptime.o
proc-y += version.o
+proc-y += softirqs.o
proc-$(CONFIG_PROC_SYSCTL) += proc_sysctl.o
proc-$(CONFIG_NET) += proc_net.o
proc-$(CONFIG_PROC_KCORE) += kcore.o
diff --git a/fs/proc/softirqs.c b/fs/proc/softirqs.c
new file mode 100644
index 0000000..1807c24
--- /dev/null
+++ b/fs/proc/softirqs.c
@@ -0,0 +1,44 @@
+#include <linux/init.h>
+#include <linux/kernel_stat.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+
+/*
+ * /proc/softirqs ... display the number of softirqs
+ */
+static int show_softirqs(struct seq_file *p, void *v)
+{
+ int i, j;
+
+ seq_printf(p, " ");
+ for_each_possible_cpu(i)
+ seq_printf(p, "CPU%-8d", i);
+ seq_printf(p, "\n");
+
+ for (i = 0; i < NR_SOFTIRQS; i++) {
+ seq_printf(p, "%8s:", softirq_to_name[i]);
+ for_each_possible_cpu(j)
+ seq_printf(p, " %10u", kstat_softirqs_cpu(i, j));
+ seq_printf(p, "\n");
+ }
+ return 0;
+}
+
+static int softirqs_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, show_softirqs, NULL);
+}
+
+static const struct file_operations proc_softirqs_operations = {
+ .open = softirqs_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static int __init proc_softirqs_init(void)
+{
+ proc_create("softirqs", 0, NULL, &proc_softirqs_operations);
+ return 0;
+}
+module_init(proc_softirqs_init);
diff --git a/fs/proc/stat.c b/fs/proc/stat.c
index 81e4eb6..7cc726c 100644
--- a/fs/proc/stat.c
+++ b/fs/proc/stat.c
@@ -29,6 +29,8 @@
cputime64_t user, nice, system, idle, iowait, irq, softirq, steal;
cputime64_t guest;
u64 sum = 0;
+ u64 sum_softirq = 0;
+ unsigned int per_softirq_sums[NR_SOFTIRQS] = {0};
struct timespec boottime;
unsigned int per_irq_sum;
@@ -53,6 +55,13 @@
sum += kstat_irqs_cpu(j, i);
}
sum += arch_irq_stat_cpu(i);
+
+ for (j = 0; j < NR_SOFTIRQS; j++) {
+ unsigned int softirq_stat = kstat_softirqs_cpu(j, i);
+
+ per_softirq_sums[j] += softirq_stat;
+ sum_softirq += softirq_stat;
+ }
}
sum += arch_irq_stat();
@@ -115,6 +124,12 @@
nr_running(),
nr_iowait());
+ seq_printf(p, "softirq %llu", (unsigned long long)sum_softirq);
+
+ for (i = 0; i < NR_SOFTIRQS; i++)
+ seq_printf(p, " %u", per_softirq_sums[i]);
+ seq_printf(p, "\n");
+
return 0;
}