s390/irq: remove split irq fields from /proc/stat

Now that irq sum accounting for /proc/stat's "intr" line works again we
have the oddity that the sum field (first field) contains only the sum
of the second (external irqs) and third field (I/O interrupts).
The reason for that is that these two fields are already sums of all other
fields. So if we would sum up everything we would count every interrupt
twice.
This is broken since the split interrupt accounting was merged two years
ago: 052ff461c8427629aee887ccc27478fc7373237c "[S390] irq: have detailed
statistics for interrupt types".
To fix this remove the split interrupt fields from /proc/stat's "intr"
line again and only have them in /proc/interrupts.

This restores the old behaviour, seems to be the only sane fix and mimics
a behaviour from other architectures where /proc/interrupts also contains
more than /proc/stat's "intr" line does.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

10 files changed, 131 insertions, 89 deletions

diff --git a/arch/s390/include/asm/irq.h b/arch/s390/include/asm/irq.h
index e6972f85d2b0..c98dcac70ae0 100644
--- a/arch/s390/include/asm/irq.h
+++ b/arch/s390/include/asm/irq.h
@@ -2,43 +2,60 @@
 #define _ASM_IRQ_H
 
 #include <linux/hardirq.h>
+#include <linux/percpu.h>
+#include <linux/cache.h>
 #include <linux/types.h>
 
-enum interruption_class {
+enum interruption_main_class {
 	EXTERNAL_INTERRUPT,
 	IO_INTERRUPT,
-	EXTINT_CLK,
-	EXTINT_EXC,
-	EXTINT_EMS,
-	EXTINT_TMR,
-	EXTINT_TLA,
-	EXTINT_PFL,
-	EXTINT_DSD,
-	EXTINT_VRT,
-	EXTINT_SCP,
-	EXTINT_IUC,
-	EXTINT_CMS,
-	EXTINT_CMC,
-	EXTINT_CMR,
-	IOINT_CIO,
-	IOINT_QAI,
-	IOINT_DAS,
-	IOINT_C15,
-	IOINT_C70,
-	IOINT_TAP,
-	IOINT_VMR,
-	IOINT_LCS,
-	IOINT_CLW,
-	IOINT_CTC,
-	IOINT_APB,
-	IOINT_ADM,
-	IOINT_CSC,
-	IOINT_PCI,
-	IOINT_MSI,
+	NR_IRQS
+};
+
+enum interruption_class {
+	IRQEXT_CLK,
+	IRQEXT_EXC,
+	IRQEXT_EMS,
+	IRQEXT_TMR,
+	IRQEXT_TLA,
+	IRQEXT_PFL,
+	IRQEXT_DSD,
+	IRQEXT_VRT,
+	IRQEXT_SCP,
+	IRQEXT_IUC,
+	IRQEXT_CMS,
+	IRQEXT_CMC,
+	IRQEXT_CMR,
+	IRQIO_CIO,
+	IRQIO_QAI,
+	IRQIO_DAS,
+	IRQIO_C15,
+	IRQIO_C70,
+	IRQIO_TAP,
+	IRQIO_VMR,
+	IRQIO_LCS,
+	IRQIO_CLW,
+	IRQIO_CTC,
+	IRQIO_APB,
+	IRQIO_ADM,
+	IRQIO_CSC,
+	IRQIO_PCI,
+	IRQIO_MSI,
 	NMI_NMI,
-	NR_IRQS,
+	NR_ARCH_IRQS
 };
 
+struct irq_stat {
+	unsigned int irqs[NR_ARCH_IRQS];
+};
+
+DECLARE_PER_CPU_SHARED_ALIGNED(struct irq_stat, irq_stat);
+
+static __always_inline void inc_irq_stat(enum interruption_class irq)
+{
+	__get_cpu_var(irq_stat).irqs[irq]++;
+}
+
 struct ext_code {
 	unsigned short subcode;
 	unsigned short code;
diff --git a/arch/s390/kernel/irq.c b/arch/s390/kernel/irq.c
index a8f8ab027ba8..5f5462447aff 100644
--- a/arch/s390/kernel/irq.c
+++ b/arch/s390/kernel/irq.c
@@ -24,42 +24,63 @@
 #include <asm/irq.h>
 #include "entry.h"
 
+DEFINE_PER_CPU_SHARED_ALIGNED(struct irq_stat, irq_stat);
+EXPORT_PER_CPU_SYMBOL_GPL(irq_stat);
+
 struct irq_class {
 	char *name;
 	char *desc;
 };
 
-static const struct irq_class intrclass_names[] = {
+/*
+ * The list of "main" irq classes on s390. This is the list of interrrupts
+ * that appear both in /proc/stat ("intr" line) and /proc/interrupts.
+ * Historically only external and I/O interrupts have been part of /proc/stat.
+ * We can't add the split external and I/O sub classes since the first field
+ * in the "intr" line in /proc/stat is supposed to be the sum of all other
+ * fields.
+ * Since the external and I/O interrupt fields are already sums we would end
+ * up with having a sum which accounts each interrupt twice.
+ */
+static const struct irq_class irqclass_main_desc[NR_IRQS] = {
 	[EXTERNAL_INTERRUPT] = {.name = "EXT"},
-	[IO_INTERRUPT]	     = {.name = "I/O"},
-	[EXTINT_CLK] = {.name = "CLK", .desc = "[EXT] Clock Comparator"},
-	[EXTINT_EXC] = {.name = "EXC", .desc = "[EXT] External Call"},
-	[EXTINT_EMS] = {.name = "EMS", .desc = "[EXT] Emergency Signal"},
-	[EXTINT_TMR] = {.name = "TMR", .desc = "[EXT] CPU Timer"},
-	[EXTINT_TLA] = {.name = "TAL", .desc = "[EXT] Timing Alert"},
-	[EXTINT_PFL] = {.name = "PFL", .desc = "[EXT] Pseudo Page Fault"},
-	[EXTINT_DSD] = {.name = "DSD", .desc = "[EXT] DASD Diag"},
-	[EXTINT_VRT] = {.name = "VRT", .desc = "[EXT] Virtio"},
-	[EXTINT_SCP] = {.name = "SCP", .desc = "[EXT] Service Call"},
-	[EXTINT_IUC] = {.name = "IUC", .desc = "[EXT] IUCV"},
-	[EXTINT_CMS] = {.name = "CMS", .desc = "[EXT] CPU-Measurement: Sampling"},
-	[EXTINT_CMC] = {.name = "CMC", .desc = "[EXT] CPU-Measurement: Counter"},
-	[EXTINT_CMR] = {.name = "CMR", .desc = "[EXT] CPU-Measurement: RI"},
-	[IOINT_CIO]  = {.name = "CIO", .desc = "[I/O] Common I/O Layer Interrupt"},
-	[IOINT_QAI]  = {.name = "QAI", .desc = "[I/O] QDIO Adapter Interrupt"},
-	[IOINT_DAS]  = {.name = "DAS", .desc = "[I/O] DASD"},
-	[IOINT_C15]  = {.name = "C15", .desc = "[I/O] 3215"},
-	[IOINT_C70]  = {.name = "C70", .desc = "[I/O] 3270"},
-	[IOINT_TAP]  = {.name = "TAP", .desc = "[I/O] Tape"},
-	[IOINT_VMR]  = {.name = "VMR", .desc = "[I/O] Unit Record Devices"},
-	[IOINT_LCS]  = {.name = "LCS", .desc = "[I/O] LCS"},
-	[IOINT_CLW]  = {.name = "CLW", .desc = "[I/O] CLAW"},
-	[IOINT_CTC]  = {.name = "CTC", .desc = "[I/O] CTC"},
-	[IOINT_APB]  = {.name = "APB", .desc = "[I/O] AP Bus"},
-	[IOINT_ADM]  = {.name = "ADM", .desc = "[I/O] EADM Subchannel"},
-	[IOINT_CSC]  = {.name = "CSC", .desc = "[I/O] CHSC Subchannel"},
-	[IOINT_PCI]  = {.name = "PCI", .desc = "[I/O] PCI Interrupt" },
-	[IOINT_MSI] =  {.name = "MSI", .desc = "[I/O] MSI Interrupt" },
+	[IO_INTERRUPT]	     = {.name = "I/O"}
+};
+
+/*
+ * The list of split external and I/O interrupts that appear only in
+ * /proc/interrupts.
+ * In addition this list contains non external / I/O events like NMIs.
+ */
+static const struct irq_class irqclass_sub_desc[NR_ARCH_IRQS] = {
+	[IRQEXT_CLK] = {.name = "CLK", .desc = "[EXT] Clock Comparator"},
+	[IRQEXT_EXC] = {.name = "EXC", .desc = "[EXT] External Call"},
+	[IRQEXT_EMS] = {.name = "EMS", .desc = "[EXT] Emergency Signal"},
+	[IRQEXT_TMR] = {.name = "TMR", .desc = "[EXT] CPU Timer"},
+	[IRQEXT_TLA] = {.name = "TAL", .desc = "[EXT] Timing Alert"},
+	[IRQEXT_PFL] = {.name = "PFL", .desc = "[EXT] Pseudo Page Fault"},
+	[IRQEXT_DSD] = {.name = "DSD", .desc = "[EXT] DASD Diag"},
+	[IRQEXT_VRT] = {.name = "VRT", .desc = "[EXT] Virtio"},
+	[IRQEXT_SCP] = {.name = "SCP", .desc = "[EXT] Service Call"},
+	[IRQEXT_IUC] = {.name = "IUC", .desc = "[EXT] IUCV"},
+	[IRQEXT_CMS] = {.name = "CMS", .desc = "[EXT] CPU-Measurement: Sampling"},
+	[IRQEXT_CMC] = {.name = "CMC", .desc = "[EXT] CPU-Measurement: Counter"},
+	[IRQEXT_CMR] = {.name = "CMR", .desc = "[EXT] CPU-Measurement: RI"},
+	[IRQIO_CIO]  = {.name = "CIO", .desc = "[I/O] Common I/O Layer Interrupt"},
+	[IRQIO_QAI]  = {.name = "QAI", .desc = "[I/O] QDIO Adapter Interrupt"},
+	[IRQIO_DAS]  = {.name = "DAS", .desc = "[I/O] DASD"},
+	[IRQIO_C15]  = {.name = "C15", .desc = "[I/O] 3215"},
+	[IRQIO_C70]  = {.name = "C70", .desc = "[I/O] 3270"},
+	[IRQIO_TAP]  = {.name = "TAP", .desc = "[I/O] Tape"},
+	[IRQIO_VMR]  = {.name = "VMR", .desc = "[I/O] Unit Record Devices"},
+	[IRQIO_LCS]  = {.name = "LCS", .desc = "[I/O] LCS"},
+	[IRQIO_CLW]  = {.name = "CLW", .desc = "[I/O] CLAW"},
+	[IRQIO_CTC]  = {.name = "CTC", .desc = "[I/O] CTC"},
+	[IRQIO_APB]  = {.name = "APB", .desc = "[I/O] AP Bus"},
+	[IRQIO_ADM]  = {.name = "ADM", .desc = "[I/O] EADM Subchannel"},
+	[IRQIO_CSC]  = {.name = "CSC", .desc = "[I/O] CHSC Subchannel"},
+	[IRQIO_PCI]  = {.name = "PCI", .desc = "[I/O] PCI Interrupt" },
+	[IRQIO_MSI]  = {.name = "MSI", .desc = "[I/O] MSI Interrupt" },
 	[NMI_NMI]    = {.name = "NMI", .desc = "[NMI] Machine Check"},
 };
 
@@ -68,30 +89,34 @@ static const struct irq_class intrclass_names[] = {
  */
 int show_interrupts(struct seq_file *p, void *v)
 {
-	int i = *(loff_t *) v, j;
+	int irq = *(loff_t *) v;
+	int cpu;
 
 	get_online_cpus();
-	if (i == 0) {
+	if (irq == 0) {
 		seq_puts(p, "           ");
-		for_each_online_cpu(j)
-			seq_printf(p, "CPU%d       ",j);
+		for_each_online_cpu(cpu)
+			seq_printf(p, "CPU%d       ", cpu);
 		seq_putc(p, '\n');
 	}
-
-	if (i < NR_IRQS) {
-		seq_printf(p, "%s: ", intrclass_names[i].name);
-#ifndef CONFIG_SMP
-		seq_printf(p, "%10u ", kstat_irqs(i));
-#else
-		for_each_online_cpu(j)
-			seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
-#endif
-		if (intrclass_names[i].desc)
-			seq_printf(p, "  %s", intrclass_names[i].desc);
-                seq_putc(p, '\n');
-        }
+	if (irq < NR_IRQS) {
+		seq_printf(p, "%s: ", irqclass_main_desc[irq].name);
+		for_each_online_cpu(cpu)
+			seq_printf(p, "%10u ", kstat_cpu(cpu).irqs[irq]);
+		seq_putc(p, '\n');
+		goto skip_arch_irqs;
+	}
+	for (irq = 0; irq < NR_ARCH_IRQS; irq++) {
+		seq_printf(p, "%s: ", irqclass_sub_desc[irq].name);
+		for_each_online_cpu(cpu)
+			seq_printf(p, "%10u ", per_cpu(irq_stat, cpu).irqs[irq]);
+		if (irqclass_sub_desc[irq].desc)
+			seq_printf(p, "  %s", irqclass_sub_desc[irq].desc);
+		seq_putc(p, '\n');
+	}
+skip_arch_irqs:
 	put_online_cpus();
-        return 0;
+	return 0;
 }
 
 /*
diff --git a/arch/s390/kernel/nmi.c b/arch/s390/kernel/nmi.c
index a6daa5c5cdb0..7918fbea36bb 100644
--- a/arch/s390/kernel/nmi.c
+++ b/arch/s390/kernel/nmi.c
@@ -254,7 +254,7 @@ void notrace s390_do_machine_check(struct pt_regs *regs)
 	int umode;
 
 	nmi_enter();
-	kstat_cpu(smp_processor_id()).irqs[NMI_NMI]++;
+	inc_irq_stat(NMI_NMI);
 	mci = (struct mci *) &S390_lowcore.mcck_interruption_code;
 	mcck = &__get_cpu_var(cpu_mcck);
 	umode = user_mode(regs);
diff --git a/arch/s390/kernel/perf_cpum_cf.c b/arch/s390/kernel/perf_cpum_cf.c
index c4e7269d4a09..86ec7447e1f5 100644
--- a/arch/s390/kernel/perf_cpum_cf.c
+++ b/arch/s390/kernel/perf_cpum_cf.c
@@ -229,7 +229,7 @@ static void cpumf_measurement_alert(struct ext_code ext_code,
 	if (!(alert & CPU_MF_INT_CF_MASK))
 		return;
 
-	kstat_cpu(smp_processor_id()).irqs[EXTINT_CMC]++;
+	inc_irq_stat(IRQEXT_CMC);
 	cpuhw = &__get_cpu_var(cpu_hw_events);
 
 	/* Measurement alerts are shared and might happen when the PMU
diff --git a/arch/s390/kernel/runtime_instr.c b/arch/s390/kernel/runtime_instr.c
index 61066f6f71a5..077a99389b07 100644
--- a/arch/s390/kernel/runtime_instr.c
+++ b/arch/s390/kernel/runtime_instr.c
@@ -71,7 +71,7 @@ static void runtime_instr_int_handler(struct ext_code ext_code,
 	if (!(param32 & CPU_MF_INT_RI_MASK))
 		return;
 
-	kstat_cpu(smp_processor_id()).irqs[EXTINT_CMR]++;
+	inc_irq_stat(IRQEXT_CMR);
 
 	if (!current->thread.ri_cb)
 		return;
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 82664a3c17ee..4a36d5b5e4c9 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -433,9 +433,9 @@ static void do_ext_call_interrupt(struct ext_code ext_code,
 
 	cpu = smp_processor_id();
 	if (ext_code.code == 0x1202)
-		kstat_cpu(cpu).irqs[EXTINT_EXC]++;
+		inc_irq_stat(IRQEXT_EXC);
 	else
-		kstat_cpu(cpu).irqs[EXTINT_EMS]++;
+		inc_irq_stat(IRQEXT_EMS);
 	/*
 	 * handle bit signal external calls
 	 */
diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c
index 7fcd690d42c7..aff0e350d776 100644
--- a/arch/s390/kernel/time.c
+++ b/arch/s390/kernel/time.c
@@ -168,7 +168,7 @@ static void clock_comparator_interrupt(struct ext_code ext_code,
 				       unsigned int param32,
 				       unsigned long param64)
 {
-	kstat_cpu(smp_processor_id()).irqs[EXTINT_CLK]++;
+	inc_irq_stat(IRQEXT_CLK);
 	if (S390_lowcore.clock_comparator == -1ULL)
 		set_clock_comparator(S390_lowcore.clock_comparator);
 }
@@ -179,7 +179,7 @@ static void stp_timing_alert(struct stp_irq_parm *);
 static void timing_alert_interrupt(struct ext_code ext_code,
 				   unsigned int param32, unsigned long param64)
 {
-	kstat_cpu(smp_processor_id()).irqs[EXTINT_TLA]++;
+	inc_irq_stat(IRQEXT_TLA);
 	if (param32 & 0x00c40000)
 		etr_timing_alert((struct etr_irq_parm *) &param32);
 	if (param32 & 0x00038000)
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index 42601d6e166f..2fb9e63b8fc4 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -569,7 +569,7 @@ static void pfault_interrupt(struct ext_code ext_code,
 	subcode = ext_code.subcode;
 	if ((subcode & 0xff00) != __SUBCODE_MASK)
 		return;
-	kstat_cpu(smp_processor_id()).irqs[EXTINT_PFL]++;
+	inc_irq_stat(IRQEXT_PFL);
 	/* Get the token (= pid of the affected task). */
 	pid = sizeof(void *) == 4 ? param32 : param64;
 	rcu_read_lock();
diff --git a/arch/s390/oprofile/hwsampler.c b/arch/s390/oprofile/hwsampler.c
index 0cb385da202c..b5b2916895e0 100644
--- a/arch/s390/oprofile/hwsampler.c
+++ b/arch/s390/oprofile/hwsampler.c
@@ -233,7 +233,7 @@ static void hws_ext_handler(struct ext_code ext_code,
 	if (!(param32 & CPU_MF_INT_SF_MASK))
 		return;
 
-	kstat_cpu(smp_processor_id()).irqs[EXTINT_CMS]++;
+	inc_irq_stat(IRQEXT_CMS);
 	atomic_xchg(&cb->ext_params, atomic_read(&cb->ext_params) | param32);
 
 	if (hws_wq)
diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index e985744f6334..60e0372545d2 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -440,7 +440,7 @@ static void zpci_irq_handler(void *dont, void *need)
 	int rescan = 0, max = aisb_max;
 	struct zdev_irq_map *imap;
 
-	kstat_cpu(smp_processor_id()).irqs[IOINT_PCI]++;
+	inc_irq_stat(IRQIO_PCI);
 	sbit = start;
 
 scan:
@@ -452,7 +452,7 @@ scan:
 		/* find vector bit */
 		imap = bucket->imap[sbit];
 		for_each_set_bit_left(mbit, &imap->aibv, imap->msi_vecs) {
-			kstat_cpu(smp_processor_id()).irqs[IOINT_MSI]++;
+			inc_irq_stat(IRQIO_MSI);
 			clear_bit(63 - mbit, &imap->aibv);
 
 			spin_lock(&imap->lock);