[PATCH v3 16/16] ARM: Remove custom IRQ stat accounting

Marc Zyngier
2020-09-01T14:53:04Z

Let's switch the arm code to the core accounting, which already
does everything we need.

Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
arch/arm/include/asm/hardirq.h | 17 -----------------
arch/arm/kernel/smp.c | 20 ++++----------------
2 files changed, 4 insertions(+), 33 deletions(-)

diff --git a/arch/arm/include/asm/hardirq.h b/arch/arm/include/asm/hardirq.h
index 7a88f160b1fb..b95848ed2bc7 100644
--- a/arch/arm/include/asm/hardirq.h
+++ b/arch/arm/include/asm/hardirq.h
@@ -6,29 +6,12 @@
#include <linux/threads.h>
#include <asm/irq.h>

-/* number of IPIS _not_ including IPI_CPU_BACKTRACE */
-#define NR_IPI 7
-
typedef struct {
unsigned int __softirq_pending;
-#ifdef CONFIG_SMP
- unsigned int ipi_irqs[NR_IPI];
-#endif
} ____cacheline_aligned irq_cpustat_t;

#include <linux/irq_cpustat.h> /* Standard mappings for irq_cpustat_t above */

-#define __inc_irq_stat(cpu, member) __IRQ_STAT(cpu, member)++
-#define __get_irq_stat(cpu, member) __IRQ_STAT(cpu, member)
-
-#ifdef CONFIG_SMP
-u64 smp_irq_stat_cpu(unsigned int cpu);
-#else
-#define smp_irq_stat_cpu(cpu) 0
-#endif
-
-#define arch_irq_stat_cpu smp_irq_stat_cpu
-
#define __ARCH_IRQ_EXIT_IRQS_DISABLED 1

#endif /* __ASM_HARDIRQ_H */
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index d51e64955a26..aead847ac8b9 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -65,6 +65,7 @@ enum ipi_msg_type {
IPI_CPU_STOP,
IPI_IRQ_WORK,
IPI_COMPLETION,
+ NR_IPI,
/*
* CPU_BACKTRACE is special and not included in NR_IPI
* or tracable with trace_ipi_*
@@ -529,27 +530,16 @@ void show_ipi_list(struct seq_file *p, int prec)
unsigned int cpu, i;

for (i = 0; i < NR_IPI; i++) {
+ unsigned int irq = irq_desc_get_irq(ipi_desc[i]);
seq_printf(p, "%*s%u: ", prec - 1, "IPI", i);

for_each_online_cpu(cpu)
- seq_printf(p, "%10u ",
- __get_irq_stat(cpu, ipi_irqs[i]));
+ seq_printf(p, "%10u ", kstat_irqs_cpu(irq, cpu));

seq_printf(p, " %s\n", ipi_types[i]);
}
}

-u64 smp_irq_stat_cpu(unsigned int cpu)
-{
- u64 sum = 0;
- int i;
-
- for (i = 0; i < NR_IPI; i++)
- sum += __get_irq_stat(cpu, ipi_irqs[i]);
-
- return sum;
-}
-
void arch_send_call_function_ipi_mask(const struct cpumask *mask)
{
smp_cross_call(mask, IPI_CALL_FUNC);
@@ -630,10 +620,8 @@ static void do_handle_IPI(int ipinr)
{
unsigned int cpu = smp_processor_id();

- if ((unsigned)ipinr < NR_IPI) {
+ if ((unsigned)ipinr < NR_IPI)
trace_ipi_entry_rcuidle(ipi_types[ipinr]);
- __inc_irq_stat(cpu, ipi_irqs[ipinr]);
- }

switch (ipinr) {
case IPI_WAKEUP:
--
2.27.0