Merge "Perf: arm64: add perf trace user" (3e284bf3) · Commits · e / devices / android_kernel_sony_msm8994

arch/arm64/kernel/Makefile

+2 −1

Original line number	Original line	Diff line number	Diff line
	@@ -25,7 +25,8 @@ arm64-obj-$(CONFIG_MODULES) += arm64ksyms.o module.o
	arm64-obj-$(CONFIG_SMP) += smp.o smp_spin_table.o topology.o		arm64-obj-$(CONFIG_SMP) += smp.o smp_spin_table.o topology.o
	arm64-obj-$(CONFIG_PERF_EVENTS) += perf_regs.o		arm64-obj-$(CONFIG_PERF_EVENTS) += perf_regs.o
	arm64-obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o perf_debug.o \		arm64-obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o perf_debug.o \
	perf_trace_counters.o		perf_trace_counters.o \
			perf_trace_user.o
	arm64-obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o		arm64-obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o
	arm64-obj-$(CONFIG_EARLY_PRINTK) += early_printk.o		arm64-obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
	arm64-obj-$(CONFIG_ARM64_CPU_SUSPEND) += sleep.o suspend.o		arm64-obj-$(CONFIG_ARM64_CPU_SUSPEND) += sleep.o suspend.o

arch/arm64/kernel/perf_debug.c

+1 −0

Original line number	Original line	Diff line number	Diff line
	@@ -38,6 +38,7 @@ static char *descriptions =
	"13 Perf: arm64: restore registers after reset\n"		"13 Perf: arm64: restore registers after reset\n"
	"14 Perf: arm64: stop counters when going into hotplug\n"		"14 Perf: arm64: stop counters when going into hotplug\n"
	"15 Perf: arm64: make debug dir handle exportable\n"		"15 Perf: arm64: make debug dir handle exportable\n"
			"16 Perf: arm64: add perf trace user\n"
	;		;

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

arch/arm64/kernel/perf_trace_user.c

0 → 100644

+96 −0

Original line number	Original line	Diff line number	Diff line
			/* Copyright (c) 2014, The Linux Foundation. All rights reserved.
			*
			* This program is free software; you can redistribute it and/or modify
			* it under the terms of the GNU General Public License version 2 and
			* only version 2 as published by the Free Software Foundation.
			*
			* This program is distributed in the hope that it will be useful,
			* but WITHOUT ANY WARRANTY; without even the implied warranty of
			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
			* GNU General Public License for more details.
			*/
			#include <linux/perf_event.h>
			#include <linux/types.h>
			#include <linux/tracepoint.h>
			#include <linux/fs.h>
			#include <linux/debugfs.h>
			#include <linux/preempt.h>
			#include <linux/stat.h>
			#include <asm/uaccess.h>

			#define CREATE_TRACE_POINTS
			#include "perf_trace_user.h"

			#undef TRACE_SYSTEM
			#define TRACE_SYSTEM perf_trace_counters

			#define TRACE_USER_MAX_BUF_SIZE 100

			static ssize_t perf_trace_write(struct file *file,
			const char __user *user_string_in,
			size_t len, loff_t *ppos)
			{
			u32 cnten_val;
			int rc;
			char buf[TRACE_USER_MAX_BUF_SIZE + 1];
			ssize_t length;

			if (len == 0)
			return 0;

			length = len > TRACE_USER_MAX_BUF_SIZE ? TRACE_USER_MAX_BUF_SIZE : len;

			rc = copy_from_user(buf, user_string_in, length);
			if (rc) {
			pr_err("%s copy_from_user failed, rc=%d\n", __func__, rc);
			return length;
			}

			/* Remove any trailing newline and make sure string is terminated */
			if (buf[length - 1] == '\n')
			buf[length - 1] = '\0';
			else
			buf[length] = '\0';

			/*
			* Disable preemption to ensure that all the performance counter
			* accesses happen on the same cpu
			*/
			preempt_disable();
			/* stop counters, call the trace function, restart them */

			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));

			trace_perf_trace_user(buf, cnten_val);

			/* Enable all the counters that were disabled */
			asm volatile("msr pmcntenset_el0, %0" : : "r" (cnten_val));
			preempt_enable();

			return length;
			}

			static const struct file_operations perf_trace_fops = {
			.write = perf_trace_write
			};

			static int __init init_perf_trace(void)
			{
			struct dentry *dir;
			struct dentry *file;
			unsigned int value = 1;

			dir = perf_create_debug_dir();
			if (!dir)
			return -ENOMEM;
			file = debugfs_create_file("trace_marker", S_IWUSR \| S_IWGRP, dir,
			&value, &perf_trace_fops);
			if (!file)
			return -ENOMEM;

			return 0;
			}

			late_initcall(init_perf_trace);

arch/arm64/kernel/perf_trace_user.h

0 → 100644

+85 −0

Original line number	Original line	Diff line number	Diff line
			/* Copyright (c) 2014, The Linux Foundation. All rights reserved.
			*
			* This program is free software; you can redistribute it and/or modify
			* it under the terms of the GNU General Public License version 2 and
			* only version 2 as published by the Free Software Foundation.
			*
			* This program is distributed in the hope that it will be useful,
			* but WITHOUT ANY WARRANTY; without even the implied warranty of
			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
			* GNU General Public License for more details.
			*/
			#if !defined(_PERF_TRACE_USER_H_) \|\| defined(TRACE_HEADER_MULTI_READ)
			#define _PERF_TRACE_USER_H_

			#undef TRACE_SYSTEM
			#define TRACE_SYSTEM perf_trace_counters

			#include <linux/tracepoint.h>

			#define CNTENSET_CC 0x80000000
			#define NUM_L1_CTRS 4

			TRACE_EVENT(perf_trace_user,
			TP_PROTO(char *string, u32 cnten_val),
			TP_ARGS(string, cnten_val),

			TP_STRUCT__entry(
			__field(u32, cctr)
			__field(u32, ctr0)
			__field(u32, ctr1)
			__field(u32, ctr2)
			__field(u32, ctr3)
			__field(u32, lctr0)
			__field(u32, lctr1)
			__string(user_string, string)
			),

			TP_fast_assign(
			u32 cnt;
			u32 l1_cnts[NUM_L1_CTRS];
			int i;

			if (cnten_val & CNTENSET_CC) {
			/* Read value */
			asm volatile("mrs %0, pmccntr_el0" : "=r" (cnt));
			__entry->cctr = cnt;
			} else
			__entry->cctr = 0;
			for (i = 0; i < NUM_L1_CTRS; i++) {
			if (cnten_val & (1 << i)) {
			/* Select */
			asm volatile("msr pmselr_el0, %0"
			: : "r" (i));
			isb();
			/* Read value */
			asm volatile("mrs %0, pmxevcntr_el0"
			: "=r" (cnt));
			l1_cnts[i] = cnt;
			} else {
			l1_cnts[i] = 0;
			}
			}

			__entry->ctr0 = l1_cnts[0];
			__entry->ctr1 = l1_cnts[1];
			__entry->ctr2 = l1_cnts[2];
			__entry->ctr3 = l1_cnts[3];
			__entry->lctr0 = 0;
			__entry->lctr1 = 0;
			__assign_str(user_string, string);
			),

			TP_printk("CCNTR: %u, CTR0: %u, CTR1: %u, CTR2: %u, CTR3: %u, L2CTR0: %u, L2CTR1: %u, MSG=%s",
			__entry->cctr, __entry->ctr0, __entry->ctr1,
			__entry->ctr2, __entry->ctr3,
			__entry->lctr0, __entry->lctr1,
			__get_str(user_string)
			)
			);

			#endif
			#undef TRACE_INCLUDE_PATH
			#define TRACE_INCLUDE_PATH ../../arch/arm64/kernel
			#define TRACE_INCLUDE_FILE perf_trace_user
			#include <trace/define_trace.h>