Merge "sched: Add trace point to track preemption disable callers" (2e2bf895) · Commits · e / devices / android_kernel_oneplus_sm8150

include/linux/sched/sysctl.h

+6 −0

Original line number	Diff line number	Diff line
		@@ -48,6 +48,12 @@ walt_proc_update_handler(struct ctl_table *table, int write,

		#endif

		#if defined(CONFIG_DEBUG_PREEMPT) \|\| defined(CONFIG_PREEMPT_TRACER) \|\| \
		defined(CONFIG_PREEMPTIRQ_EVENTS)
		extern unsigned int sysctl_preemptoff_tracing_threshold_ns;

		#endif

		enum sched_tunable_scaling {
		SCHED_TUNABLESCALING_NONE,
		SCHED_TUNABLESCALING_LOG,

include/trace/events/sched.h

+32 −0

Original line number	Diff line number	Diff line
		@@ -1298,6 +1298,38 @@ TRACE_EVENT(sched_isolate,
		__entry->time, __entry->isolate)
		);

		TRACE_EVENT(sched_preempt_disable,

		TP_PROTO(u64 delta, bool irqs_disabled,
		unsigned long caddr0, unsigned long caddr1,
		unsigned long caddr2, unsigned long caddr3),

		TP_ARGS(delta, irqs_disabled, caddr0, caddr1, caddr2, caddr3),

		TP_STRUCT__entry(
		__field(u64, delta)
		__field(bool, irqs_disabled)
		__field(void*, caddr0)
		__field(void*, caddr1)
		__field(void*, caddr2)
		__field(void*, caddr3)
		),

		TP_fast_assign(
		__entry->delta = delta;
		__entry->irqs_disabled = irqs_disabled;
		__entry->caddr0 = (void *)caddr0;
		__entry->caddr1 = (void *)caddr1;
		__entry->caddr2 = (void *)caddr2;
		__entry->caddr3 = (void *)caddr3;
		),

		TP_printk("delta=%llu(ns) irqs_d=%d Callers:(%pf<-%pf<-%pf<-%pf)",
		__entry->delta, __entry->irqs_disabled,
		__entry->caddr0, __entry->caddr1,
		__entry->caddr2, __entry->caddr3)
		);

		#include "walt.h"

		#endif /* CONFIG_SMP */

kernel/sched/core.c

+37 −1

Original line number	Diff line number	Diff line
		@@ -88,6 +88,12 @@ int sysctl_sched_rt_runtime = 950000;
		/* CPUs with isolated domains */
		cpumask_var_t cpu_isolated_map;

		/*
		* preemptoff stack tracing threshold in ns.
		* default: 1ms
		*/
		unsigned int sysctl_preemptoff_tracing_threshold_ns = 1000000UL;

		/*
		* __task_rq_lock - lock the rq @p resides on.
		*/
		@@ -3191,17 +3197,34 @@ u64 scheduler_tick_max_deferment(void)

		#if defined(CONFIG_PREEMPT) && (defined(CONFIG_DEBUG_PREEMPT) \|\| \
		defined(CONFIG_PREEMPT_TRACER))

		struct preempt_store {
		u64 ts;
		unsigned long caddr[4];
		bool irqs_disabled;
		};

		DEFINE_PER_CPU(struct preempt_store, the_ps);
		/*
		* If the value passed in is equal to the current preempt count
		* then we just disabled preemption. Start timing the latency.
		*/
		static inline void preempt_latency_start(int val)
		{
		struct preempt_store *ps = &per_cpu(the_ps, raw_smp_processor_id());

		if (preempt_count() == val) {
		unsigned long ip = get_lock_parent_ip();
		#ifdef CONFIG_DEBUG_PREEMPT
		current->preempt_disable_ip = ip;
		#endif
		ps->ts = sched_clock();
		ps->caddr[0] = CALLER_ADDR0;
		ps->caddr[1] = CALLER_ADDR1;
		ps->caddr[2] = CALLER_ADDR2;
		ps->caddr[3] = CALLER_ADDR3;
		ps->irqs_disabled = irqs_disabled();

		trace_preempt_off(CALLER_ADDR0, ip);
		}
		}
		@@ -3234,9 +3257,22 @@ NOKPROBE_SYMBOL(preempt_count_add);
		*/
		static inline void preempt_latency_stop(int val)
		{
		if (preempt_count() == val)
		if (preempt_count() == val) {
		struct preempt_store *ps = &per_cpu(the_ps,
		raw_smp_processor_id());
		u64 delta = sched_clock() - ps->ts;

		/*
		* Trace preempt disable stack if preemption
		* is disabled for more than the threshold.
		*/
		if (delta > sysctl_preemptoff_tracing_threshold_ns)
		trace_sched_preempt_disable(delta, ps->irqs_disabled,
		ps->caddr[0], ps->caddr[1],
		ps->caddr[2], ps->caddr[3]);
		trace_preempt_on(CALLER_ADDR0, get_lock_parent_ip());
		}
		}

		void preempt_count_sub(int val)
		{

kernel/sysctl.c

+10 −0

Original line number	Diff line number	Diff line
		@@ -310,6 +310,16 @@ static struct ctl_table kern_table[] = {
		.mode = 0644,
		.proc_handler = proc_dointvec,
		},
		#if defined(CONFIG_DEBUG_PREEMPT) \|\| defined(CONFIG_PREEMPT_TRACER) \|\| \
		defined(CONFIG_PREEMPTIRQ_EVENTS)
		{
		.procname = "preemptoff_tracing_threshold_ns",
		.data = &sysctl_preemptoff_tracing_threshold_ns,
		.maxlen = sizeof(unsigned int),
		.mode = 0644,
		.proc_handler = proc_dointvec,
		},
		#endif
		#ifdef CONFIG_SCHED_WALT
		{
		.procname = "sched_cpu_high_irqload",