The following commit has been merged into the irq/core branch of tip:
Commit-ID: fb4f676fc901cb547226efb3e69ffeaeefa124be
Gitweb: https://git.kernel.org/tip/fb4f676fc901cb547226efb3e69ffeaeefa124be
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Thu, 10 Dec 2020 20:25:41 +01:00
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Sat, 12 Dec 2020 12:59:03 +01:00
genirq: Annotate irq stats data races
Both the per cpu stats and the accumulated count are accessed lockless and
can be concurrently modified. That's intentional and the stats are a rough
estimate anyway. Annotate them with data_race().
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20201210194043.067097663@xxxxxxxxxxxxx
---
kernel/irq/irqdesc.c | 4 ++--
kernel/irq/proc.c | 5 +++--
2 files changed, 5 insertions(+), 4 deletions(-)
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index f309869..d28f69e 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -943,10 +943,10 @@ unsigned int kstat_irqs(unsigned int irq)
if (!irq_settings_is_per_cpu_devid(desc) &&
!irq_settings_is_per_cpu(desc) &&
!irq_is_nmi(desc))
- return desc->tot_count;
+ return data_race(desc->tot_count);
for_each_possible_cpu(cpu)
- sum += *per_cpu_ptr(desc->kstat_irqs, cpu);
+ sum += data_race(*per_cpu_ptr(desc->kstat_irqs, cpu));
return sum;
}
diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c
index 72513ed..9813878 100644
--- a/kernel/irq/proc.c
+++ b/kernel/irq/proc.c
@@ -488,9 +488,10 @@ int show_interrupts(struct seq_file *p, void *v)
if (!desc || irq_settings_is_hidden(desc))
goto outsparse;
- if (desc->kstat_irqs)
+ if (desc->kstat_irqs) {
for_each_online_cpu(j)
- any_count |= *per_cpu_ptr(desc->kstat_irqs, j);
+ any_count |= data_race(*per_cpu_ptr(desc->kstat_irqs, j));
+ }
if ((!desc->action || irq_desc_is_chained(desc)) && !any_count)
goto outsparse;
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