[linux-2.6-block.git] / drivers / scsi / snic / snic_trc.c

/*
 * Copyright 2014 Cisco Systems, Inc.  All rights reserved.
 *
 * This program is free software; you may redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <linux/module.h>
#include <linux/mempool.h>
#include <linux/errno.h>
#include <linux/vmalloc.h>

#include "snic_io.h"
#include "snic.h"

/*
 * snic_get_trc_buf : Allocates a trace record and returns.
 */
struct snic_trc_data *
snic_get_trc_buf(void)
{
	struct snic_trc *trc = &snic_glob->trc;
	struct snic_trc_data *td = NULL;
	unsigned long flags;

	spin_lock_irqsave(&trc->lock, flags);
	td = &trc->buf[trc->wr_idx];
	trc->wr_idx++;

	if (trc->wr_idx == trc->max_idx)
		trc->wr_idx = 0;

	if (trc->wr_idx != trc->rd_idx) {
		spin_unlock_irqrestore(&trc->lock, flags);

		goto end;
	}

	trc->rd_idx++;
	if (trc->rd_idx == trc->max_idx)
		trc->rd_idx = 0;

	td->ts = 0;	/* Marker for checking the record, for complete data*/
	spin_unlock_irqrestore(&trc->lock, flags);

end:

	return td;
} /* end of snic_get_trc_buf */

/*
 * snic_fmt_trc_data : Formats trace data for printing.
 */
static int
snic_fmt_trc_data(struct snic_trc_data *td, char *buf, int buf_sz)
{
	int len = 0;
	struct timespec64 tmspec;

	jiffies_to_timespec64(td->ts, &tmspec);

	len += snprintf(buf, buf_sz,
			"%llu.%09lu %-25s %3d %4x %16llx %16llx %16llx %16llx %16llx\n",
			tmspec.tv_sec,
			tmspec.tv_nsec,
			td->fn,
			td->hno,
			td->tag,
			td->data[0], td->data[1], td->data[2], td->data[3],
			td->data[4]);

	return len;
} /* end of snic_fmt_trc_data */

/*
 * snic_get_trc_data : Returns a formatted trace buffer.
 */
int
snic_get_trc_data(char *buf, int buf_sz)
{
	struct snic_trc_data *td = NULL;
	struct snic_trc *trc = &snic_glob->trc;
	unsigned long flags;

	spin_lock_irqsave(&trc->lock, flags);
	if (trc->rd_idx == trc->wr_idx) {
		spin_unlock_irqrestore(&trc->lock, flags);

		return -1;
	}
	td = &trc->buf[trc->rd_idx];

	if (td->ts == 0) {
		/* write in progress. */
		spin_unlock_irqrestore(&trc->lock, flags);

		return -1;
	}

	trc->rd_idx++;
	if (trc->rd_idx == trc->max_idx)
		trc->rd_idx = 0;
	spin_unlock_irqrestore(&trc->lock, flags);

	return snic_fmt_trc_data(td, buf, buf_sz);
} /* end of snic_get_trc_data */

/*
 * snic_trc_init() : Configures Trace Functionality for snic.
 */
int
snic_trc_init(void)
{
	struct snic_trc *trc = &snic_glob->trc;
	void *tbuf = NULL;
	int tbuf_sz = 0, ret;

	tbuf_sz = (snic_trace_max_pages * PAGE_SIZE);
	tbuf = vzalloc(tbuf_sz);
	if (!tbuf) {
		SNIC_ERR("Failed to Allocate Trace Buffer Size. %d\n", tbuf_sz);
		SNIC_ERR("Trace Facility not enabled.\n");
		ret = -ENOMEM;

		return ret;
	}

	trc->buf = (struct snic_trc_data *) tbuf;
	spin_lock_init(&trc->lock);

	snic_trc_debugfs_init();

	trc->max_idx = (tbuf_sz / SNIC_TRC_ENTRY_SZ);
	trc->rd_idx = trc->wr_idx = 0;
	trc->enable = true;
	SNIC_INFO("Trace Facility Enabled.\n Trace Buffer SZ %lu Pages.\n",
		  tbuf_sz / PAGE_SIZE);
	ret = 0;

	return ret;
} /* end of snic_trc_init */

/*
 * snic_trc_free : Releases the trace buffer and disables the tracing.
 */
void
snic_trc_free(void)
{
	struct snic_trc *trc = &snic_glob->trc;

	trc->enable = false;
	snic_trc_debugfs_term();

	if (trc->buf) {
		vfree(trc->buf);
		trc->buf = NULL;
	}

	SNIC_INFO("Trace Facility Disabled.\n");
} /* end of snic_trc_free */
Commit	Line	Data
c8806b6c NM	1	/*
	2	* Copyright 2014 Cisco Systems, Inc. All rights reserved.
	3	*
	4	* This program is free software; you may redistribute it and/or modify
	5	* it under the terms of the GNU General Public License as published by
	6	* the Free Software Foundation; version 2 of the License.
	7	*
	8	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	9	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	10	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	11	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	12	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	13	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	14	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	15	* SOFTWARE.
	16	*/
	17
	18	#include <linux/module.h>
	19	#include <linux/mempool.h>
	20	#include <linux/errno.h>
	21	#include <linux/vmalloc.h>
	22
	23	#include "snic_io.h"
	24	#include "snic.h"
	25
	26	/*
	27	* snic_get_trc_buf : Allocates a trace record and returns.
	28	*/
	29	struct snic_trc_data *
	30	snic_get_trc_buf(void)
	31	{
	32	struct snic_trc *trc = &snic_glob->trc;
	33	struct snic_trc_data *td = NULL;
	34	unsigned long flags;
	35
	36	spin_lock_irqsave(&trc->lock, flags);
	37	td = &trc->buf[trc->wr_idx];
	38	trc->wr_idx++;
	39
	40	if (trc->wr_idx == trc->max_idx)
	41	trc->wr_idx = 0;
	42
	43	if (trc->wr_idx != trc->rd_idx) {
	44	spin_unlock_irqrestore(&trc->lock, flags);
	45
	46	goto end;
	47	}
	48
	49	trc->rd_idx++;
	50	if (trc->rd_idx == trc->max_idx)
	51	trc->rd_idx = 0;
	52
	53	td->ts = 0; /* Marker for checking the record, for complete data*/
	54	spin_unlock_irqrestore(&trc->lock, flags);
	55
	56	end:
	57
	58	return td;
	59	} /* end of snic_get_trc_buf */
	60
	61	/*
	62	* snic_fmt_trc_data : Formats trace data for printing.
	63	*/
	64	static int
65	snic_fmt_trc_data(struct snic_trc_data td, char buf, int buf_sz)
66	{
67	int len = 0;
920447f1	68	struct timespec64 tmspec;
c8806b6c	69
920447f1	70	jiffies_to_timespec64(td->ts, &tmspec);
c8806b6c NM	71
c8806b6c NM	72	len += snprintf(buf, buf_sz,
920447f1	73	"%llu.%09lu %-25s %3d %4x %16llx %16llx %16llx %16llx %16llx\n",
c8806b6c NM	74	tmspec.tv_sec,
	75	tmspec.tv_nsec,
	76	td->fn,
	77	td->hno,
	78	td->tag,
	79	td->data[0], td->data[1], td->data[2], td->data[3],
	80	td->data[4]);
	81
	82	return len;
	83	} /* end of snic_fmt_trc_data */
	84
	85	/*
	86	* snic_get_trc_data : Returns a formatted trace buffer.
	87	*/
	88	int
	89	snic_get_trc_data(char *buf, int buf_sz)
	90	{
	91	struct snic_trc_data *td = NULL;
	92	struct snic_trc *trc = &snic_glob->trc;
	93	unsigned long flags;
	94
	95	spin_lock_irqsave(&trc->lock, flags);
	96	if (trc->rd_idx == trc->wr_idx) {
	97	spin_unlock_irqrestore(&trc->lock, flags);
	98
	99	return -1;
	100	}
	101	td = &trc->buf[trc->rd_idx];
	102
	103	if (td->ts == 0) {
	104	/* write in progress. */
	105	spin_unlock_irqrestore(&trc->lock, flags);
	106
	107	return -1;
	108	}
	109
	110	trc->rd_idx++;
	111	if (trc->rd_idx == trc->max_idx)
	112	trc->rd_idx = 0;
	113	spin_unlock_irqrestore(&trc->lock, flags);
	114
	115	return snic_fmt_trc_data(td, buf, buf_sz);
	116	} /* end of snic_get_trc_data */
	117
	118	/*
	119	* snic_trc_init() : Configures Trace Functionality for snic.
	120	*/
	121	int
	122	snic_trc_init(void)
	123	{
	124	struct snic_trc *trc = &snic_glob->trc;
	125	void *tbuf = NULL;
	126	int tbuf_sz = 0, ret;
	127
	128	tbuf_sz = (snic_trace_max_pages * PAGE_SIZE);
7250d12d	129	tbuf = vzalloc(tbuf_sz);
c8806b6c NM	130	if (!tbuf) {
	131	SNIC_ERR("Failed to Allocate Trace Buffer Size. %d\n", tbuf_sz);
	132	SNIC_ERR("Trace Facility not enabled.\n");
	133	ret = -ENOMEM;
	134
	135	return ret;
	136	}
	137
c8806b6c NM	138	trc->buf = (struct snic_trc_data *) tbuf;
	139	spin_lock_init(&trc->lock);
	140
fd84ec20	141	snic_trc_debugfs_init();
c8806b6c NM	142
	143	trc->max_idx = (tbuf_sz / SNIC_TRC_ENTRY_SZ);
	144	trc->rd_idx = trc->wr_idx = 0;
621a5f7a	145	trc->enable = true;
c8806b6c NM	146	SNIC_INFO("Trace Facility Enabled.\n Trace Buffer SZ %lu Pages.\n",
	147	tbuf_sz / PAGE_SIZE);
	148	ret = 0;
	149
c8806b6c NM	150	return ret;
	151	} /* end of snic_trc_init */
	152
	153	/*
	154	* snic_trc_free : Releases the trace buffer and disables the tracing.
	155	*/
	156	void
	157	snic_trc_free(void)
	158	{
	159	struct snic_trc *trc = &snic_glob->trc;
	160
621a5f7a	161	trc->enable = false;
c8806b6c NM	162	snic_trc_debugfs_term();
	163
	164	if (trc->buf) {
	165	vfree(trc->buf);
	166	trc->buf = NULL;
	167	}
	168
	169	SNIC_INFO("Trace Facility Disabled.\n");
	170	} /* end of snic_trc_free */