Peter Zijlstra
2022-Sep-19 10:00 UTC
[PATCH v2 23/44] arm,smp: Remove trace_.*_rcuidle() usage
None of these functions should ever be ran with RCU disabled anymore.
Specifically, do_handle_IPI() is only called from handle_IPI() which
explicitly does irq_enter()/irq_exit() which ensures RCU is watching.
The problem with smp_cross_call() was, per commit 7c64cc0531fa ("arm: Use
_rcuidle for smp_cross_call() tracepoints"), that
cpuidle_enter_state_coupled() already had RCU disabled, but that's
long been fixed by commit 1098582a0f6c ("sched,idle,rcu: Push rcu_idle
deeper into the idle path").
Signed-off-by: Peter Zijlstra (Intel) <peterz at infradead.org>
---
arch/arm/kernel/smp.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -639,7 +639,7 @@ static void do_handle_IPI(int ipinr)
unsigned int cpu = smp_processor_id();
if ((unsigned)ipinr < NR_IPI)
- trace_ipi_entry_rcuidle(ipi_types[ipinr]);
+ trace_ipi_entry(ipi_types[ipinr]);
switch (ipinr) {
case IPI_WAKEUP:
@@ -686,7 +686,7 @@ static void do_handle_IPI(int ipinr)
}
if ((unsigned)ipinr < NR_IPI)
- trace_ipi_exit_rcuidle(ipi_types[ipinr]);
+ trace_ipi_exit(ipi_types[ipinr]);
}
/* Legacy version, should go away once all irqchips have been converted */
@@ -709,7 +709,7 @@ static irqreturn_t ipi_handler(int irq,
static void smp_cross_call(const struct cpumask *target, unsigned int ipinr)
{
- trace_ipi_raise_rcuidle(target, ipi_types[ipinr]);
+ trace_ipi_raise(target, ipi_types[ipinr]);
__ipi_send_mask(ipi_desc[ipinr], target);
}
Ulf Hansson
2022-Oct-04 11:08 UTC
[PATCH v2 23/44] arm,smp: Remove trace_.*_rcuidle() usage
On Mon, 19 Sept 2022 at 12:18, Peter Zijlstra <peterz at infradead.org> wrote:> > None of these functions should ever be ran with RCU disabled anymore. > > Specifically, do_handle_IPI() is only called from handle_IPI() which > explicitly does irq_enter()/irq_exit() which ensures RCU is watching. > > The problem with smp_cross_call() was, per commit 7c64cc0531fa ("arm: Use > _rcuidle for smp_cross_call() tracepoints"), that > cpuidle_enter_state_coupled() already had RCU disabled, but that's > long been fixed by commit 1098582a0f6c ("sched,idle,rcu: Push rcu_idle > deeper into the idle path"). > > Signed-off-by: Peter Zijlstra (Intel) <peterz at infradead.org>FWIW: Reviewed-by: Ulf Hansson <ulf.hansson at linaro.org> Kind regards Uffe> --- > arch/arm/kernel/smp.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > --- a/arch/arm/kernel/smp.c > +++ b/arch/arm/kernel/smp.c > @@ -639,7 +639,7 @@ static void do_handle_IPI(int ipinr) > unsigned int cpu = smp_processor_id(); > > if ((unsigned)ipinr < NR_IPI) > - trace_ipi_entry_rcuidle(ipi_types[ipinr]); > + trace_ipi_entry(ipi_types[ipinr]); > > switch (ipinr) { > case IPI_WAKEUP: > @@ -686,7 +686,7 @@ static void do_handle_IPI(int ipinr) > } > > if ((unsigned)ipinr < NR_IPI) > - trace_ipi_exit_rcuidle(ipi_types[ipinr]); > + trace_ipi_exit(ipi_types[ipinr]); > } > > /* Legacy version, should go away once all irqchips have been converted */ > @@ -709,7 +709,7 @@ static irqreturn_t ipi_handler(int irq, > > static void smp_cross_call(const struct cpumask *target, unsigned int ipinr) > { > - trace_ipi_raise_rcuidle(target, ipi_types[ipinr]); > + trace_ipi_raise(target, ipi_types[ipinr]); > __ipi_send_mask(ipi_desc[ipinr], target); > } > > > > _______________________________________________ > Virtualization mailing list > Virtualization at lists.linux-foundation.org > https://lists.linuxfoundation.org/mailman/listinfo/virtualization