[patch V6 12/16] genirq/proc: Increase default interrupt number precision to four

[Thomas Gleixner <tglx@kernel.org>]

Quite some architectures have four character wide acronyms for architecture
specific interrupts like IPI, NMI, etc.

The default precision of printing the Linux device interrupt numbers is
three, which causes quite some code to play games with adding or omitting
space after the acronym and the colon in order to keep the per CPU numbers
properly aligned.

Increase the default number precision to four in the core code and get rid
of the space games all over the place. At the same time align all
architecture specific descriptor texts left so that they show up in the
same column as the interrupt chip names, which makes the output more
uniform accross architectures. Fix up the GDB script to this new scheme as
well.

Signed-off-by: Thomas Gleixner <tglx@kernel.org>
---
V6: New patch after Michael mentioned the various alignment issues.
---
 arch/alpha/kernel/irq.c         |    8 ++++----
 arch/arm/kernel/smp.c           |    3 +--
 arch/arm64/kernel/smp.c         |    5 ++---
 arch/loongarch/kernel/smp.c     |    2 +-
 arch/riscv/kernel/smp.c         |    3 +--
 arch/sh/kernel/irq.c            |    2 +-
 arch/sparc/kernel/irq_32.c      |   12 ++++++------
 arch/sparc/kernel/irq_64.c      |    4 ++--
 arch/um/kernel/irq.c            |    4 ++--
 arch/xtensa/kernel/irq.c        |    2 +-
 kernel/irq/proc.c               |    4 ++--
 scripts/gdb/linux/interrupts.py |   16 ++++++----------
 12 files changed, 29 insertions(+), 36 deletions(-)

--- a/arch/alpha/kernel/irq.c
+++ b/arch/alpha/kernel/irq.c
@@ -72,16 +72,16 @@ int arch_show_interrupts(struct seq_file
 	int j;
 
 #ifdef CONFIG_SMP
-	seq_puts(p, "IPI: ");
+	seq_puts(p, " IPI: ");
 	for_each_online_cpu(j)
 		seq_printf(p, "%10lu ", cpu_data[j].ipi_count);
 	seq_putc(p, '\n');
 #endif
-	seq_puts(p, "PMI: ");
+	seq_puts(p, " PMI: ");
 	for_each_online_cpu(j)
 		seq_printf(p, "%10lu ", per_cpu(irq_pmi_count, j));
-	seq_puts(p, "          Performance Monitoring\n");
-	seq_printf(p, "ERR: %10lu\n", irq_err_count);
+	seq_puts(p, " Performance Monitoring\n");
+	seq_printf(p, " ERR: %10lu\n", irq_err_count);
 	return 0;
 }
 
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -551,8 +551,7 @@ void show_ipi_list(struct seq_file *p, i
 		if (!ipi_desc[i])
 			continue;
 
-		seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i,
-			   prec >= 4 ? " " : "");
+		seq_printf(p, "%*s%u:", prec - 1, "IPI", i);
 
 		for_each_online_cpu(cpu)
 			seq_printf(p, "%10u ", irq_desc_kstat_cpu(ipi_desc[i], cpu));
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -833,11 +833,10 @@ int arch_show_interrupts(struct seq_file
 	unsigned int cpu, i;
 
 	for (i = 0; i < MAX_IPI; i++) {
-		seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i,
-			   prec >= 4 ? " " : "");
+		seq_printf(p, "%*s%u: ", prec - 1, "IPI", i);
 		for_each_online_cpu(cpu)
 			seq_printf(p, "%10u ", irq_desc_kstat_cpu(get_ipi_desc(cpu, i), cpu));
-		seq_printf(p, "      %s\n", ipi_types[i]);
+		seq_printf(p, " %s\n", ipi_types[i]);
 	}
 
 	seq_printf(p, "%*s: %10lu\n", prec, "Err", irq_err_count);
--- a/arch/loongarch/kernel/smp.c
+++ b/arch/loongarch/kernel/smp.c
@@ -88,7 +88,7 @@ void show_ipi_list(struct seq_file *p, i
 	unsigned int cpu, i;
 
 	for (i = 0; i < NR_IPI; i++) {
-		seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i, prec >= 4 ? " " : "");
+		seq_printf(p, "%*s%u:", prec - 1, "IPI", i);
 		for_each_online_cpu(cpu)
 			seq_put_decimal_ull_width(p, " ", per_cpu(irq_stat, cpu).ipi_irqs[i], 10);
 		seq_printf(p, " LoongArch  %d  %s\n", i + 1, ipi_types[i]);
--- a/arch/riscv/kernel/smp.c
+++ b/arch/riscv/kernel/smp.c
@@ -226,8 +226,7 @@ void show_ipi_stats(struct seq_file *p,
 	unsigned int cpu, i;
 
 	for (i = 0; i < IPI_MAX; i++) {
-		seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i,
-			   prec >= 4 ? " " : "");
+		seq_printf(p, "%*s%u:", prec - 1, "IPI", i);
 		for_each_online_cpu(cpu)
 			seq_printf(p, "%10u ", irq_desc_kstat_cpu(ipi_desc[i], cpu));
 		seq_printf(p, " %s\n", ipi_names[i]);
--- a/arch/sh/kernel/irq.c
+++ b/arch/sh/kernel/irq.c
@@ -46,7 +46,7 @@ int arch_show_interrupts(struct seq_file
 	seq_printf(p, "%*s:", prec, "NMI");
 	for_each_online_cpu(j)
 		seq_put_decimal_ull_width(p, " ", per_cpu(irq_stat.__nmi_count, j), 10);
-	seq_printf(p, "  Non-maskable interrupts\n");
+	seq_printf(p, " Non-maskable interrupts\n");
 
 	seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
 
--- a/arch/sparc/kernel/irq_32.c
+++ b/arch/sparc/kernel/irq_32.c
@@ -199,19 +199,19 @@ int arch_show_interrupts(struct seq_file
 	int j;
 
 #ifdef CONFIG_SMP
-	seq_printf(p, "RES:");
+	seq_printf(p, "%*s:", prec, "RES");
 	for_each_online_cpu(j)
 		seq_put_decimal_ull_width(p, " ", cpu_data(j).irq_resched_count, 10);
-	seq_printf(p, "     IPI rescheduling interrupts\n");
-	seq_printf(p, "CAL:");
+	seq_printf(p, " IPI rescheduling interrupts\n");
+	seq_printf(p, "%*s:", prec, "CAL");
 	for_each_online_cpu(j)
 		seq_put_decimal_ull_width(p, " ", cpu_data(j).irq_call_count, 10);
-	seq_printf(p, "     IPI function call interrupts\n");
+	seq_printf(p, " IPI function call interrupts\n");
 #endif
-	seq_printf(p, "NMI:");
+	seq_printf(p, "%*s:", prec, "NMI");
 	for_each_online_cpu(j)
 		seq_put_decimal_ull_width(p, " ", cpu_data(j).counter, 10);
-	seq_printf(p, "     Non-maskable interrupts\n");
+	seq_printf(p, " Non-maskable interrupts\n");
 	return 0;
 }
 
--- a/arch/sparc/kernel/irq_64.c
+++ b/arch/sparc/kernel/irq_64.c
@@ -303,10 +303,10 @@ int arch_show_interrupts(struct seq_file
 {
 	int j;
 
-	seq_printf(p, "NMI:");
+	seq_printf(p, "%*s:", prec, "NMI");
 	for_each_online_cpu(j)
 		seq_put_decimal_ull_width(p, " ", cpu_data(j).__nmi_count, 10);
-	seq_printf(p, "     Non-maskable interrupts\n");
+	seq_printf(p, " Non-maskable interrupts\n");
 	return 0;
 }
 
--- a/arch/um/kernel/irq.c
+++ b/arch/um/kernel/irq.c
@@ -716,12 +716,12 @@ int arch_show_interrupts(struct seq_file
 	seq_printf(p, "%*s: ", prec, "RES");
 	for_each_online_cpu(cpu)
 		seq_printf(p, "%10u ", irq_stats(cpu)->irq_resched_count);
-	seq_puts(p, "  Rescheduling interrupts\n");
+	seq_puts(p, " Rescheduling interrupts\n");
 
 	seq_printf(p, "%*s: ", prec, "CAL");
 	for_each_online_cpu(cpu)
 		seq_printf(p, "%10u ", irq_stats(cpu)->irq_call_count);
-	seq_puts(p, "  Function call interrupts\n");
+	seq_puts(p, " Function call interrupts\n");
 #endif
 
 	return 0;
--- a/arch/xtensa/kernel/irq.c
+++ b/arch/xtensa/kernel/irq.c
@@ -59,7 +59,7 @@ int arch_show_interrupts(struct seq_file
 	seq_printf(p, "%*s:", prec, "NMI");
 	for_each_online_cpu(cpu)
 		seq_printf(p, " %10lu", per_cpu(nmi_count, cpu));
-	seq_puts(p, "   Non-maskable interrupts\n");
+	seq_puts(p, " Non-maskable interrupts\n");
 #endif
 	return 0;
 }
--- a/kernel/irq/proc.c
+++ b/kernel/irq/proc.c
@@ -459,7 +459,7 @@ int __weak arch_show_interrupts(struct s
 static struct irq_proc_constraints {
 	unsigned int	num_prec;
 } irq_proc_constraints __read_mostly = {
-	.num_prec	= 3,
+	.num_prec	= 4,
 };
 
 #ifndef ACTUAL_NR_IRQS
@@ -470,7 +470,7 @@ void irq_proc_calc_prec(void)
 {
 	unsigned int prec, n;
 
-	for (prec = 3, n = 1000; prec < 10 && n <= total_nr_irqs; ++prec)
+	for (prec = 4, n = 10000; prec < 10 && n <= total_nr_irqs; ++prec)
 		n *= 10;
 	WRITE_ONCE(irq_proc_constraints.num_prec, prec);
 }
--- a/scripts/gdb/linux/interrupts.py
+++ b/scripts/gdb/linux/interrupts.py
@@ -131,23 +131,19 @@ irq_desc_type = utils.CachedType("struct
     if nr_ipi is None or ipi_desc is None or ipi_types is None:
         return text
 
-    if prec >= 4:
-        sep = " "
-    else:
-        sep = ""
-
     for ipi in range(nr_ipi):
-        text += "%*s%u:%s" % (prec - 1, "IPI", ipi, sep)
+        text += "%*s%u: " % (prec - 1, "IPI", ipi)
         desc = ipi_desc[ipi].cast(irq_desc_type.get_type().pointer())
         if desc == 0:
             continue
         for cpu in cpus.each_online_cpu():
-            text += "%10u" % (cpus.per_cpu(desc['kstat_irqs'], cpu)['cnt'])
-        text += "      %s" % (ipi_types[ipi].string())
+            text += "%10u " % (cpus.per_cpu(desc['kstat_irqs'], cpu)['cnt'])
+        text += "%s" % (ipi_types[ipi].string())
         text += "\n"
     return text
 
 def aarch64_show_interrupts(prec):
+    # Does not work for ARM64 as "ipi_desc" is not available there
     text = arm_common_show_interrupts(prec)
     text += "%*s: %10lu\n" % (prec, "ERR", gdb.parse_and_eval("irq_err_count"))
     return text
@@ -175,8 +171,8 @@ irq_desc_type = utils.CachedType("struct
 
     def invoke(self, arg, from_tty):
         nr_irqs = gdb.parse_and_eval("total_nr_irqs")
-        prec = 3
-        j = 1000
+        prec = 4
+        j = 10000
         while prec < 10 and j <= nr_irqs:
             prec += 1
             j *= 10