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kstat cleanup

PATCH In review Ravikiran G Thirumalai 1 participant 2 messages Oct 22, 2002 – Oct 23, 2002

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Ravikiran G Thirumalai

author
#0 lore raw

PATCH 1/1 kstat cleanup

Hi Andrew,
Here's the kstat cleanup you'd suggested sometime ago. I have used Rusty's per_cpu infrastructure for the stats now. Here're the changes in short.

1. Break out disk stats from kernel_stat and move disk stat to blkdev.h
2. Group cpu stat in kernel_stat and make them "per_cpu" instead of the NR_CPUS array
3. Remove EXPORT_SYMBOL(kstat) from ksyms.c (as I noticed that no module is using kstat)

The foll patch is tested on a 4 way PIII xeon. This patch has changes for i386 files (+ arch independent changes)(.. it'll break other archs). I am in the process of changing other archs. Patch for the same to follow soon. In the meanwhile, do let me know if the patch is ok by you. Patch applies neatly on 2.5..44-mm2

Thanks,
Kiran

arch/i386/kernel/irq.c +2 -2
diff -ruN linux-2.5.44-mm2/arch/i386/kernel/irq.c kstat-2.5.44-mm2/arch/i386/kernel/irq.c
@@ -153,7 +153,7 @@
 		for (j = 0; j < NR_CPUS; j++)
 			if (cpu_online(j))
 				p += seq_printf(p, "%10u ",
-					     kstat.irqs[j][i]);
+					     kstat_cpu(j).irqs[i]);
 #endif
 		seq_printf(p, " %14s", irq_desc[i].handler->typename);
 		seq_printf(p, "  %s", action->name);

@@ -344,7 +344,7 @@
 		show_stack((void *)esp);
 	}
 #endif
-	kstat.irqs[cpu][irq]++;
+	kstat_cpu(cpu).irqs[irq]++;
 	spin_lock(&desc->lock);
 	desc->handler->ack(irq);
 	/*
arch/i386/mach-visws/visws_apic.c +1 -1
diff -ruN linux-2.5.44-mm2/arch/i386/mach-visws/visws_apic.c kstat-2.5.44-mm2/arch/i386/mach-visws/visws_apic.c
@@ -324,7 +324,7 @@
 	/*
 	 * handle this 'virtual interrupt' as a Cobalt one now.
 	 */
-	kstat.irqs[smp_processor_id()][irq]++;
+	kstat_cpu(smp_processor_id()).irqs[irq]++;
 	do_cobalt_IRQ(realirq, regs);
 
 	spin_lock(&irq_controller_lock);
drivers/block/ll_rw_blk.c +9 -5
diff -ruN linux-2.5.44-mm2/drivers/block/ll_rw_blk.c kstat-2.5.44-mm2/drivers/block/ll_rw_blk.c
@@ -27,6 +27,10 @@
 #include <linux/completion.h>
 #include <linux/slab.h>
 
+/*
+ * Disk stats 
+ */
+struct disk_stat dkstat;
 
 /*
  * For the allocated request tables

@@ -1441,13 +1445,13 @@
 	if ((index >= DK_MAX_DISK) || (major >= DK_MAX_MAJOR))
 		return;
 
-	kstat.dk_drive[major][index] += new_io;
+	dkstat.drive[major][index] += new_io;
 	if (rw == READ) {
-		kstat.dk_drive_rio[major][index] += new_io;
-		kstat.dk_drive_rblk[major][index] += nr_sectors;
+		dkstat.drive_rio[major][index] += new_io;
+		dkstat.drive_rblk[major][index] += nr_sectors;
 	} else if (rw == WRITE) {
-		kstat.dk_drive_wio[major][index] += new_io;
-		kstat.dk_drive_wblk[major][index] += nr_sectors;
+		dkstat.drive_wio[major][index] += new_io;
+		dkstat.drive_wblk[major][index] += nr_sectors;
 	} else
 		printk(KERN_ERR "drive_stat_acct: cmd not R/W?\n");
 }
fs/proc/proc_misc.c +19 -19
diff -ruN linux-2.5.44-mm2/fs/proc/proc_misc.c kstat-2.5.44-mm2/fs/proc/proc_misc.c
@@ -348,14 +348,14 @@
 		int j;
 
 		if(!cpu_online(i)) continue;
-		user += kstat.per_cpu_user[i];
-		nice += kstat.per_cpu_nice[i];
-		system += kstat.per_cpu_system[i];
-		idle += kstat.per_cpu_idle[i];
-		iowait += kstat.per_cpu_iowait[i];
+		user += kstat_cpu(i).cpustat.user;
+		nice += kstat_cpu(i).cpustat.nice;
+		system += kstat_cpu(i).cpustat.system;
+		idle += kstat_cpu(i).cpustat.idle;
+		iowait += kstat_cpu(i).cpustat.iowait;
 #if !defined(CONFIG_ARCH_S390)
 		for (j = 0 ; j < NR_IRQS ; j++)
-			sum += kstat.irqs[i][j];
+			sum += kstat_cpu(i).irqs[j];
 #endif
 	}
 

@@ -369,11 +369,11 @@
 		if (!cpu_online(i)) continue;
 		len += sprintf(page + len, "cpu%d %u %u %u %u %u\n",
 			i,
-			jiffies_to_clock_t(kstat.per_cpu_user[i]),
-			jiffies_to_clock_t(kstat.per_cpu_nice[i]),
-			jiffies_to_clock_t(kstat.per_cpu_system[i]),
-			jiffies_to_clock_t(kstat.per_cpu_idle[i]),
-			jiffies_to_clock_t(kstat.per_cpu_iowait[i]));
+			jiffies_to_clock_t(kstat_cpu(i).cpustat.user),
+			jiffies_to_clock_t(kstat_cpu(i).cpustat.nice),
+			jiffies_to_clock_t(kstat_cpu(i).cpustat.system),
+			jiffies_to_clock_t(kstat_cpu(i).cpustat.idle),
+			jiffies_to_clock_t(kstat_cpu(i).cpustat.idle));
 	}
 	len += sprintf(page + len, "intr %u", sum);
 

@@ -386,18 +386,18 @@
 
 	for (major = 0; major < DK_MAX_MAJOR; major++) {
 		for (disk = 0; disk < DK_MAX_DISK; disk++) {
-			int active = kstat.dk_drive[major][disk] +
-				kstat.dk_drive_rblk[major][disk] +
-				kstat.dk_drive_wblk[major][disk];
+			int active = dkstat.drive[major][disk] +
+				dkstat.drive_rblk[major][disk] +
+				dkstat.drive_wblk[major][disk];
 			if (active)
 				len += sprintf(page + len,
 					"(%u,%u):(%u,%u,%u,%u,%u) ",
 					major, disk,
-					kstat.dk_drive[major][disk],
-					kstat.dk_drive_rio[major][disk],
-					kstat.dk_drive_rblk[major][disk],
-					kstat.dk_drive_wio[major][disk],
-					kstat.dk_drive_wblk[major][disk]
+					dkstat.drive[major][disk],
+					dkstat.drive_rio[major][disk],
+					dkstat.drive_rblk[major][disk],
+					dkstat.drive_wio[major][disk],
+					dkstat.drive_wblk[major][disk]
 			);
 		}
 	}
include/linux/blkdev.h +16 -0
diff -ruN linux-2.5.44-mm2/include/linux/blkdev.h kstat-2.5.44-mm2/include/linux/blkdev.h
@@ -11,6 +11,22 @@
 
 #include <asm/scatterlist.h>
 
+/*
+ * Disk stats ...
+ */
+
+#define DK_MAX_MAJOR 16
+#define DK_MAX_DISK 16
+ 
+struct disk_stat {
+        unsigned int drive[DK_MAX_MAJOR][DK_MAX_DISK];
+        unsigned int drive_rio[DK_MAX_MAJOR][DK_MAX_DISK];
+        unsigned int drive_wio[DK_MAX_MAJOR][DK_MAX_DISK];
+        unsigned int drive_rblk[DK_MAX_MAJOR][DK_MAX_DISK];
+        unsigned int drive_wblk[DK_MAX_MAJOR][DK_MAX_DISK];
+};
+extern struct disk_stat dkstat;
+
 struct request_queue;
 typedef struct request_queue request_queue_t;
 struct elevator_s;
include/linux/kernel_stat.h +17 -16
diff -ruN linux-2.5.44-mm2/include/linux/kernel_stat.h kstat-2.5.44-mm2/include/linux/kernel_stat.h
@@ -5,6 +5,7 @@
 #include <asm/irq.h>
 #include <linux/smp.h>
 #include <linux/threads.h>
+#include <linux/percpu.h>
 
 /*
  * 'kernel_stat.h' contains the definitions needed for doing

@@ -12,26 +13,25 @@
  * used by rstatd/perfmeter
  */
 
-#define DK_MAX_MAJOR 16
-#define DK_MAX_DISK 16
+struct cpu_usage_stat {
+	unsigned int user;
+	unsigned int nice;
+	unsigned int system;
+	unsigned int idle;
+	unsigned int iowait;
+};
 
 struct kernel_stat {
-	unsigned int per_cpu_user[NR_CPUS],
-	             per_cpu_nice[NR_CPUS],
-	             per_cpu_system[NR_CPUS],
-	             per_cpu_idle[NR_CPUS],
-	             per_cpu_iowait[NR_CPUS];
-	unsigned int dk_drive[DK_MAX_MAJOR][DK_MAX_DISK];
-	unsigned int dk_drive_rio[DK_MAX_MAJOR][DK_MAX_DISK];
-	unsigned int dk_drive_wio[DK_MAX_MAJOR][DK_MAX_DISK];
-	unsigned int dk_drive_rblk[DK_MAX_MAJOR][DK_MAX_DISK];
-	unsigned int dk_drive_wblk[DK_MAX_MAJOR][DK_MAX_DISK];
+	struct cpu_usage_stat	cpustat;
 #if !defined(CONFIG_ARCH_S390)
-	unsigned int irqs[NR_CPUS][NR_IRQS];
+	unsigned int irqs[NR_IRQS];
 #endif
 };
 
-extern struct kernel_stat kstat;
+DECLARE_PER_CPU(struct kernel_stat, kstat);
+
+#define kstat_cpu(cpu)	per_cpu(kstat, cpu)
+#define kstat_this_cpu	kstat_cpu(smp_processor_id())
 
 extern unsigned long nr_context_switches(void);
 

@@ -50,8 +50,9 @@
 {
 	int i, sum=0;
 
-	for (i = 0 ; i < NR_CPUS ; i++)
-		sum += kstat.irqs[i][irq];
+	for (i = 0 ; i < NR_CPUS ; i++) 
+		if (cpu_possible(i)) 
+			sum += kstat_cpu(i).irqs[irq];
 
 	return sum;
 }
kernel/ksyms.c +0 -1
diff -ruN linux-2.5.44-mm2/kernel/ksyms.c kstat-2.5.44-mm2/kernel/ksyms.c
@@ -501,7 +501,6 @@
 EXPORT_SYMBOL(loops_per_jiffy);
 #endif
 
-EXPORT_SYMBOL(kstat);
 
 /* misc */
 EXPORT_SYMBOL(panic);
kernel/sched.c +42 -6

81 lines not on this page · raw message

kernel/timer.c +0 -1
diff -ruN linux-2.5.44-mm2/kernel/timer.c kstat-2.5.44-mm2/kernel/timer.c
@@ -440,7 +440,6 @@
 /* Don't completely fail for HZ > 500.  */
 int tickadj = 500/HZ ? : 1;		/* microsecs */
 
-struct kernel_stat kstat;
 
 /*
  * phase-lock loop variables
author
#1 lore raw

Hi Andrew,
Here is the kstat cleanup patch set with all the arch changes. Applies neatly on mm-3. I am mailing the url since both the patches exceed 40k limit by 900 bytes :). The first patch is for generic+i386 changes, the second patch is for arch specific changes for all other archs. Tested well on a PIII 4 way.

Patches can be found at:
http://osdn.dl.sourceforge.net/sourceforge/lse/kstat-2.5.44-mm3-2.patch
and
http://osdn.dl.sourceforge.net/sourceforge/lse/kstat-arch-2.5.44-mm3.patch

Thanks,
Kiran

Quoted 16 lines · Ravikiran G Thirumalai

Hi Andrew,
Here's the kstat cleanup you'd suggested sometime ago. I have used Rusty's per_cpu infrastructure for the stats now. Here're the changes in short.

1. Break out disk stats from kernel_stat and move disk stat to blkdev.h
2. Group cpu stat in kernel_stat and make them "per_cpu" instead of the NR_CPUS array
3. Remove EXPORT_SYMBOL(kstat) from ksyms.c (as I noticed that no module is using kstat)

The foll patch is tested on a 4 way PIII xeon. This patch has changes for i386 files (+ arch independent changes)(.. it'll break other archs). I am in the process of changing other archs. Patch for the same to follow soon. In the meanwhile, do let me know if the patch is ok by you. Patch applies neatly on 2.5..44-mm2