drm/msm: remove deprecated msm event log facility

/* Copyright (c) 2016, 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.

 */

#define pr_fmt(fmt)	"msm_evtlog:[%s] " fmt, __func__

#include "msm_evtlog.h"

#include <linux/slab.h>

#include <linux/sched.h>

#include <asm-generic/current.h>

#include <linux/uaccess.h>

#include <linux/debugfs.h>

#include "sde_trace.h"

#define SIZE_MASK(x) (x - 1)

static int msm_evtlog_debugfs_dump(struct seq_file *s, void *data)

{

	struct msm_evtlog *log = s->private;

	unsigned long cnt;	/* # of samples since clear */

	unsigned long n;	/* # of samples to print, also head index */

	unsigned long i;

	struct timespec timespec;

	/**

	 * Prints in chronological order, oldest -> newest

	 * Note due to lock-less design, the first few printed entries

	 * may be corrupted by new writer not oldest.

	 * This is a tradeoff for speed of sampling

	 */

	cnt = atomic_read(&log->cnt);

	if (!cnt)

		return 0;

	n = cnt & SIZE_MASK(log->size);

	/**

	 * If not full, print from first log

	 * (which is index 1 since atomic_inc_return is prefix operator)

	 */

	i = (cnt < log->size) ? 0 : n;

	seq_puts(s, "time_ns, pid, func, line, val1, val2, msg\n");

	do {

		i = (i + 1) & SIZE_MASK(log->size);

		timespec = ktime_to_timespec(log->events[i].ktime);

		seq_printf(s, "[%5lu.%06lu], %d, %s, %d, %llu, %llu, %s\n",

				timespec.tv_sec,

				timespec.tv_nsec / 1000,

				log->events[i].pid,

				log->events[i].func,

				log->events[i].line,

				log->events[i].val1,

				log->events[i].val2,

				log->events[i].msg);

	} while (i != n);

	return 0;

}

static int msm_evtlog_debugfs_open_dump(struct inode *inode, struct file *file)

{

	return single_open(file, msm_evtlog_debugfs_dump, inode->i_private);

}

static ssize_t msm_evtlog_debugfs_write(

		struct file *file,

		const char __user *user_buf,

		size_t size,

		loff_t *ppos)

{

	struct seq_file *s = file->private_data;

	struct msm_evtlog *log = s->private;

	char buf[64];

	int buf_size;

	buf_size = min(size, (sizeof(buf) - 1));

	if (strncpy_from_user(buf, user_buf, buf_size) < 0)

		return -EFAULT;

	buf[buf_size] = 0;

	if (strcmp(buf, "0") == 0)

		atomic_set(&log->cnt, 0);

	return size;

}

static const struct file_operations msm_evtlog_fops = {

	.open =		msm_evtlog_debugfs_open_dump,

	.read =		seq_read,

	.write =	msm_evtlog_debugfs_write,

	.llseek =	seq_lseek,

	.release =	single_release,

};

int msm_evtlog_init(

		struct msm_evtlog *log,

		int size,

		struct dentry *parent)

{

	if (!log || size < 1) {

		pr_err("Invalid params\n");

		return -EINVAL;

	}

	memset(log, 0, sizeof(*log));

	log->size = roundup_pow_of_two(size);

	log->events = kcalloc(log->size, sizeof(struct msm_evtlog_evt),

			GFP_KERNEL);

	if (!log->events) {

		pr_err("Insufficient memory\n");

		return -ENOMEM;

	}

	atomic_set(&log->cnt, 0);

	log->dentry = debugfs_create_file("evtlog", 0644, parent,

			log, &msm_evtlog_fops);

	if (IS_ERR_OR_NULL(log->dentry)) {

		int rc = PTR_ERR(log->dentry);

		pr_err("debugfs create file failed, rc=%d\n", rc);

		kfree(log->events);

		return rc;

	}

	return 0;

}

void msm_evtlog_destroy(struct msm_evtlog *log)

{

	debugfs_remove(log->dentry);

	/* Caller needs to make sure that log sampling has stopped */

	kfree(log->events);

}

void msm_evtlog_sample(

		struct msm_evtlog *log,

		const char *func,

		const char *msg,

		uint64_t val1,

		uint64_t val2,

		uint32_t line)

{

	unsigned long i;

	/**

	 * Since array sized with pow of 2, roll to 0 when cnt overflows

	 * mod the value with the size to get current idx into array

	 */

	i = (unsigned long)(atomic_inc_return(&log->cnt)) &

			SIZE_MASK(log->size);

	log->events[i].ktime = ktime_get();

	log->events[i].func = func;

	log->events[i].msg = msg;

	log->events[i].val1 = val1;

	log->events[i].val2 = val2;

	log->events[i].line = line;

	log->events[i].pid = current->pid;

	trace_sde_evtlog(func, line, val1, val2);

}