Merge "Perf: arm64: Refine disable/enable in tracecounters" (b660e914) · Commits · e / devices / android_kernel_sony_msm8994

arch/arm64/kernel/perf_debug.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -33,6 +33,7 @@ static char *descriptions =
		" 8 Perf: arm64: Use device tree property for CTI PMU workaround\n"
		" 9 Perf: arm64: make request irq pmu-dependent\n"
		"10 Perf: arm64: tracectr: initialize counts after hotplug\n"
		"11 Perf: arm64: Refine disable/enable in tracecounters\n"
		;

		static ssize_t desc_read(struct file fp, char __user buf,

arch/arm64/kernel/perf_trace_counters.c

+11 −8

Original line number	Diff line number	Diff line
		@@ -19,6 +19,7 @@

		static unsigned int tp_pid_state;

		DEFINE_PER_CPU(u32, cntenset_val);
		DEFINE_PER_CPU(u32, previous_ccnt);
		DEFINE_PER_CPU(u32[NUM_L1_CTRS], previous_l1_cnts);
		DEFINE_PER_CPU(u32, old_pid);
		@@ -39,14 +40,10 @@ static struct notifier_block tracectr_cpu_hotplug_notifier_block = {
		.notifier_call = tracectr_cpu_hotplug_notifier,
		};

		static void setup_prev_cnts(u32 cpu)
		static void setup_prev_cnts(u32 cpu, u32 cnten_val)
		{
		int i;
		u32 cnten_val;

		asm volatile("mrs %0, pmcntenset_el0" : "=r" (cnten_val));
		/* Disable all the counters that were enabled */
		asm volatile("msr pmcntenclr_el0, %0" : : "r" (cnten_val));
		if (cnten_val & CC)
		asm volatile("mrs %0, pmccntr_el0"
		: "=r"(per_cpu(previous_ccnt, cpu)));
		@@ -61,13 +58,12 @@ static void setup_prev_cnts(u32 cpu)
		: "=r"(per_cpu(previous_l1_cnts[i], cpu)));
		}
		}
		/* Enable all the counters that were disabled */
		asm volatile("msr pmcntenset_el0, %0" : : "r" (cnten_val));
		}

		void tracectr_notifier(void ignore, struct task_struct prev,
		struct task_struct *next)
		{
		u32 cnten_val;
		int current_pid;
		u32 cpu = task_thread_info(next)->cpu;

		@@ -75,14 +71,21 @@ void tracectr_notifier(void ignore, struct task_struct prev,
		return;
		current_pid = next->pid;
		if (per_cpu(old_pid, cpu) != -1) {
		asm volatile("mrs %0, pmcntenset_el0" : "=r" (cnten_val));
		per_cpu(cntenset_val, cpu) = cnten_val;
		/* Disable all the counters that were enabled */
		asm volatile("msr pmcntenclr_el0, %0" : : "r" (cnten_val));

		if (per_cpu(hotplug_flag, cpu) == 1) {
		per_cpu(hotplug_flag, cpu) = 0;
		setup_prev_cnts(cpu);
		setup_prev_cnts(cpu, cnten_val);
		} else {
		trace_sched_switch_with_ctrs(per_cpu(old_pid, cpu),
		current_pid);
		}

		/* Enable all the counters that were disabled */
		asm volatile("msr pmcntenset_el0, %0" : : "r" (cnten_val));
		}
		per_cpu(old_pid, cpu) = current_pid;
		}

arch/arm64/kernel/perf_trace_counters.h

+2 −9

Original line number	Diff line number	Diff line
		@@ -29,6 +29,7 @@
		#include <linux/cpumask.h>
		#include <linux/tracepoint.h>

		DECLARE_PER_CPU(u32, cntenset_val);
		DECLARE_PER_CPU(u32, previous_ccnt);
		DECLARE_PER_CPU(u32[NUM_L1_CTRS], previous_l1_cnts);
		TRACE_EVENT(sched_switch_with_ctrs,
		@@ -59,13 +60,8 @@ TRACE_EVENT(sched_switch_with_ctrs,
		__entry->old_pid = prev;
		__entry->new_pid = next;

		cnten_val = per_cpu(cntenset_val, cpu);

		/* Read PMCNTENSET */
		asm volatile("mrs %0, pmcntenset_el0"
		: "=r" (cnten_val));
		/* Disable all the counters that were enabled */
		asm volatile("msr pmcntenclr_el0, %0"
		: : "r" (cnten_val));
		if (cnten_val & CC) {
		asm volatile("mrs %0, pmccntr_el0"
		: "=r" (total_ccnt));
		@@ -90,9 +86,6 @@ TRACE_EVENT(sched_switch_with_ctrs,
		} else
		delta_l1_cnts[i] = 0;
		}
		/* Enable all the counters that were disabled */
		asm volatile("msr pmcntenset_el0, %0"
		: : "r" (cnten_val));

		__entry->ctr0 = delta_l1_cnts[0];
		__entry->ctr1 = delta_l1_cnts[1];