shfs_stats.h

/*
 * Simple hash filesystem (SHFS)
 *
 * Authors: Simon Kuenzer <simon.kuenzer@neclab.eu>
 *
 *
 * Copyright (c) 2013-2017, NEC Europe Ltd., NEC Corporation All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holder nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 */
#ifndef _SHFS_STATS_H_
#define _SHFS_STATS_H_

#include "shfs_stats_data.h"
#include "shfs_btable.h"
#include "shfs_fio.h"
#include "shfs.h"
#include "likely.h"
#ifdef HAVE_CTLDIR
#include <target/ctldir.h>
#endif

/*
 * Retrieve stats structure from SHFS btable entry
 */
#define shfs_stats_from_bentry(bentry) \
	(&((bentry)->hstats))

/*
 * Retrieves stats structure from an SHFS_FD
 * NOTE: No NULL check is made since it is assumed that
 * f is provided by the currently mounted shfs hash table
 * -> bentry does exist
 */
static inline struct shfs_el_stats *shfs_stats_from_fd(SHFS_FD f) {
	struct shfs_bentry *bentry = (struct shfs_bentry *) f;

	return shfs_stats_from_bentry(bentry);
}

/*
 * Retrieves stats element from miss stats table
 * NOTE: A new entry is created automatically, if it does not
 * exist yet
 */
static inline struct shfs_el_stats *shfs_stats_from_mstats(hash512_t h) {
	int is_new;
	struct htable_el *el;
	struct shfs_el_stats *el_stats;

	el = htable_lookup_add(shfs_vol.mstats.el_ht, h, &is_new);
	if (unlikely(!el))
		return NULL;

	el_stats = (struct shfs_el_stats *) el->private;
	if (is_new)
		memset(el_stats, 0, sizeof(*el_stats));
	return el_stats;
}

/*
 * Deletes an entry from mstat table
 */
static inline void shfs_stats_mstats_drop(hash512_t h) {
	struct htable_el *el;

	el = htable_lookup(shfs_vol.mstats.el_ht, h);
	if (!el)
		return;
	htable_rm(shfs_vol.mstats.el_ht, el);
}

/*
 * Resetting statistics
 */
static inline void shfs_reset_mstats(void) {
	htable_clear(shfs_vol.mstats.el_ht);
	shfs_vol.mstats.i = 0;
	shfs_vol.mstats.e = 0;
}

static inline void shfs_reset_hstats(void) {
	struct htable_el *el;
	struct shfs_el_stats *el_stats;

	foreach_htable_el(shfs_vol.bt, el) {
		el_stats = shfs_stats_from_bentry((struct shfs_bentry *) el->private);
		memset(el_stats, 0, sizeof(*el_stats));
	}
}

#define shfs_reset_stats() \
	do { \
		shfs_reset_hstats(); \
		shfs_reset_mstats(); \
	} while (0)

/*
 * Dumps statistics of element entries
 */
typedef int (*shfs_dump_el_stats_t)(void *argp, hash512_t h, int loaded, struct shfs_el_stats *stats);

int shfs_dump_mstats(shfs_dump_el_stats_t dump_el, void *dump_el_argp);
int shfs_dump_hstats(shfs_dump_el_stats_t dump_el, void *dump_el_argp);

static inline int shfs_dump_stats(shfs_dump_el_stats_t dump_el, void *dump_el_argp)
{
	int ret;
	ret = shfs_dump_hstats(dump_el, dump_el_argp);
	if (unlikely(ret < 0))
		return ret;
	ret = shfs_dump_mstats(dump_el, dump_el_argp);
	if (unlikely(ret < 0))
		return ret;
	return 0;
}

/*
 * Tools to display/export stats via uSh/ctldir
 */
int init_shfs_stats_export(blkdev_id_t bd_id);
#ifdef HAVE_CTLDIR
int register_shfs_stats_tools(struct ctldir *cd);
#else
int register_shfs_stats_tools(void);
#endif
void exit_shfs_stats_export(void);

#endif /* _SHFS_STATS_H_ */