On Mon, 29 Mar 2021 09:52:10 +0100,
Jingyi Wang <wangjingyi11@xxxxxxxxxx> wrote:
Currently, arm use gic_ipi_send_mask() to inject single IPI, which
make the procedure a little complex. We use gic_ipi_send_single()
instead as some other archs.
Signed-off-by: Jingyi Wang <wangjingyi11@xxxxxxxxxx>
---
arch/arm/kernel/smp.c | 16 +++++++++++++---
arch/arm64/kernel/smp.c | 16 +++++++++++++---
2 files changed, 26 insertions(+), 6 deletions(-)
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 74679240a9d8..369ce529cdd8 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -534,6 +534,8 @@ static const char *ipi_types[NR_IPI] __tracepoint_string = {
};
static void smp_cross_call(const struct cpumask *target, unsigned int ipinr);
+static void smp_cross_call_single(const struct cpumask *target, int cpu,
+ unsigned int ipinr);
Why does this function need to take both a cpumask *and* a cpu, given
that they represent the same thing?
I was intended to use the extra param to reuse trace_ipi_raise_rcuidle.
I ignored that, thanks.
void show_ipi_list(struct seq_file *p, int prec)
{
@@ -564,14 +566,15 @@ void arch_send_wakeup_ipi_mask(const struct cpumask *mask)
void arch_send_call_function_single_ipi(int cpu)
{
- smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC);
+ smp_cross_call_single(cpumask_of(cpu), cpu, IPI_CALL_FUNC);
}
#ifdef CONFIG_IRQ_WORK
void arch_irq_work_raise(void)
{
+ int cpu = smp_processor_id();
if (arch_irq_work_has_interrupt())
- smp_cross_call(cpumask_of(smp_processor_id()), IPI_IRQ_WORK);
+ smp_cross_call(cpumask_of(cpu), cpu, IPI_IRQ_WORK);
Why isn't that a call to smp_cross_call_single()?
}
#endif
@@ -707,6 +710,13 @@ static void smp_cross_call(const struct cpumask *target, unsigned int ipinr)
__ipi_send_mask(ipi_desc[ipinr], target);
}
+static void smp_cross_call_single(const struct cpumask *target, int cpu,
+ unsigned int ipinr)
+{
+ trace_ipi_raise_rcuidle(target, ipi_types[ipinr]);
Why don't you compute the cpumask here^^?
+ __ipi_send_single(ipi_desc[ipinr], cpu);
+}
+
static void ipi_setup(int cpu)
{
int i;
@@ -744,7 +754,7 @@ void __init set_smp_ipi_range(int ipi_base, int n)
void smp_send_reschedule(int cpu)
{
- smp_cross_call(cpumask_of(cpu), IPI_RESCHEDULE);
+ smp_cross_call_single(cpumask_of(cpu), cpu, IPI_RESCHEDULE);
}
void smp_send_stop(void)
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index 357590beaabb..d290b6dc5a6e 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
Similar comments for the arm64 side.
Overall, this needs to be backed by data that indicates that there is
an actual benefit for this extra complexity.
Thanks,
M.