Commit cc9cb0a7 authored by Valentin Schneider's avatar Valentin Schneider Committed by Peter Zijlstra
Browse files

sched, smp: Trace IPIs sent via send_call_function_single_ipi() 



send_call_function_single_ipi() is the thing that sends IPIs at the bottom
of smp_call_function*() via either generic_exec_single() or
smp_call_function_many_cond(). Give it an IPI-related tracepoint.

Note that this ends up tracing any IPI sent via __smp_call_single_queue(),
which covers __ttwu_queue_wakelist() and irq_work_queue_on() "for free".

Signed-off-by: default avatarValentin Schneider <vschneid@redhat.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: default avatarIngo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20230307143558.294354-3-vschneid@redhat.com
parent 56eb0598

arch/arm/kernel/smp.c

+0 −1
Original line number Diff line number Diff line
@@ -48,7 +48,6 @@ 
#include <asm/mach/arch.h>

#include <asm/mpu.h>



#define CREATE_TRACE_POINTS

#include <trace/events/ipi.h>



/*

arch/arm64/kernel/smp.c

+0 −1
Original line number Diff line number Diff line
@@ -51,7 +51,6 @@ 
#include <asm/ptrace.h>

#include <asm/virt.h>



#define CREATE_TRACE_POINTS

#include <trace/events/ipi.h>



DEFINE_PER_CPU_READ_MOSTLY(int, cpu_number);

kernel/sched/core.c

+7 −2
Original line number Diff line number Diff line
@@ -80,6 +80,7 @@ 
#define CREATE_TRACE_POINTS

#include <linux/sched/rseq_api.h>

#include <trace/events/sched.h>

#include <trace/events/ipi.h>

#undef CREATE_TRACE_POINTS



#include "sched.h"
@@ -95,6 +96,8 @@ 
#include "../../io_uring/io-wq.h"

#include "../smpboot.h"



EXPORT_TRACEPOINT_SYMBOL_GPL(ipi_send_cpumask);



/*

 * Export tracepoints that act as a bare tracehook (ie: have no trace event

 * associated with them) to allow external modules to probe them.
@@ -3830,11 +3833,13 @@ void send_call_function_single_ipi(int cpu) 
{

	struct rq *rq = cpu_rq(cpu);



	if (!set_nr_if_polling(rq->idle))

	if (!set_nr_if_polling(rq->idle)) {

		trace_ipi_send_cpumask(cpumask_of(cpu), _RET_IP_, NULL);

		arch_send_call_function_single_ipi(cpu);

	else

	} else {

		trace_sched_wake_idle_without_ipi(cpu);

	}

}



/*

 * Queue a task on the target CPUs wake_list and wake the CPU via IPI if

kernel/smp.c

+2 −0
Original line number Diff line number Diff line
@@ -26,6 +26,8 @@ 
#include <linux/sched/debug.h>

#include <linux/jump_label.h>



#include <trace/events/ipi.h>



#include "smpboot.h"

#include "sched/smp.h"