/*
* Copyright (c) 1997, 1998, 1999 Kenneth D. Merry.
* 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. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*
* $FreeBSD$
*/
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/bio.h>
#include <sys/sysctl.h>
#include <sys/devicestat.h>
static int devstat_num_devs;
static long devstat_generation;
static int devstat_version = DEVSTAT_VERSION;
static int devstat_current_devnumber;
static STAILQ_HEAD(devstatlist, devstat) device_statq;
/*
* Take a malloced and zeroed devstat structure given to us, fill it in
* and add it to the queue of devices.
*/
void
devstat_add_entry(struct devstat *ds, const char *dev_name,
int unit_number, u_int32_t block_size,
devstat_support_flags flags,
devstat_type_flags device_type,
devstat_priority priority)
{
struct devstatlist *devstat_head;
struct devstat *ds_tmp;
if (ds == NULL)
return;
if (devstat_num_devs == 0)
STAILQ_INIT(&device_statq);
devstat_generation++;
devstat_num_devs++;
devstat_head = &device_statq;
/*
* Priority sort. Each driver passes in its priority when it adds
* its devstat entry. Drivers are sorted first by priority, and
* then by probe order.
*
* For the first device, we just insert it, since the priority
* doesn't really matter yet. Subsequent devices are inserted into
* the list using the order outlined above.
*/
if (devstat_num_devs == 1)
STAILQ_INSERT_TAIL(devstat_head, ds, dev_links);
else {
for (ds_tmp = STAILQ_FIRST(devstat_head); ds_tmp != NULL;
ds_tmp = STAILQ_NEXT(ds_tmp, dev_links)) {
struct devstat *ds_next;
ds_next = STAILQ_NEXT(ds_tmp, dev_links);
/*
* If we find a break between higher and lower
* priority items, and if this item fits in the
* break, insert it. This also applies if the
* "lower priority item" is the end of the list.
*/
if ((priority <= ds_tmp->priority)
&& ((ds_next == NULL)
|| (priority > ds_next->priority))) {
STAILQ_INSERT_AFTER(devstat_head, ds_tmp, ds,
dev_links);
break;
} else if (priority > ds_tmp->priority) {
/*
* If this is the case, we should be able
* to insert ourselves at the head of the
* list. If we can't, something is wrong.
*/
if (ds_tmp == STAILQ_FIRST(devstat_head)) {
STAILQ_INSERT_HEAD(devstat_head,
ds, dev_links);
break;
} else {
STAILQ_INSERT_TAIL(devstat_head,
ds, dev_links);
printf("devstat_add_entry: HELP! "
"sorting problem detected "
"for %s%d\n", dev_name,
unit_number);
break;
}
}
}
}
ds->device_number = devstat_current_devnumber++;
ds->unit_number = unit_number;
strncpy(ds->device_name, dev_name, DEVSTAT_NAME_LEN);
ds->device_name[DEVSTAT_NAME_LEN - 1] = '\0';
ds->block_size = block_size;
ds->flags = flags;
ds->device_type = device_type;
ds->priority = priority;
getmicrotime(&ds->dev_creation_time);
}
/*
* Remove a devstat structure from the list of devices.
*/
void
devstat_remove_entry(struct devstat *ds)
{
struct devstatlist *devstat_head;
if (ds == NULL)
return;
devstat_generation++;
devstat_num_devs--;
devstat_head = &device_statq;
/* Remove this entry from the devstat queue */
STAILQ_REMOVE(devstat_head, ds, devstat, dev_links);
}
/*
* Record a transaction start.
*/
void
devstat_start_transaction(struct devstat *ds)
{
/* sanity check */
if (ds == NULL)
return;
/*
* We only want to set the start time when we are going from idle
* to busy. The start time is really the start of the latest busy
* period.
*/
if (ds->busy_count == 0)
getmicrouptime(&ds->start_time);
ds->busy_count++;
}
/*
* Record the ending of a transaction, and incrment the various counters.
*/
void
devstat_end_transaction(struct devstat *ds, u_int32_t bytes,
devstat_tag_type tag_type, devstat_trans_flags flags)
{
struct timeval busy_time;
/* sanity check */
if (ds == NULL)
return;
getmicrouptime(&ds->last_comp_time);
ds->busy_count--;
/*
* There might be some transactions (DEVSTAT_NO_DATA) that don't
* transfer any data.
*/
if (flags == DEVSTAT_READ) {
ds->bytes_read += bytes;
ds->num_reads++;
} else if (flags == DEVSTAT_WRITE) {
ds->bytes_written += bytes;
ds->num_writes++;
} else if (flags == DEVSTAT_FREE) {
ds->bytes_freed += bytes;
ds->num_frees++;
} else
ds->num_other++;
/*
* Keep a count of the various tag types sent.
*/
if ((ds->flags & DEVSTAT_NO_ORDERED_TAGS) == 0 &&
tag_type != DEVSTAT_TAG_NONE)
ds->tag_types[tag_type]++;
/*
* We only update the busy time when we go idle. Otherwise, this
* calculation would require many more clock cycles.
*/
if (ds->busy_count == 0) {
/* Calculate how long we were busy */
busy_time = ds->last_comp_time;
timevalsub(&busy_time, &ds->start_time);
/* Add our busy time to the total busy time. */
timevaladd(&ds->busy_time, &busy_time);
} else if (ds->busy_count < 0)
printf("devstat_end_transaction: HELP!! busy_count "
"for %s%d is < 0 (%d)!\n", ds->device_name,
ds->unit_number, ds->busy_count);
}
void
devstat_end_transaction_bio(struct devstat *ds, struct bio *bp)
{
devstat_trans_flags flg;
if (bp->bio_cmd == BIO_DELETE)
flg = DEVSTAT_FREE;
else if (bp->bio_cmd == BIO_READ)
flg = DEVSTAT_READ;
else
flg = DEVSTAT_WRITE;
devstat_end_transaction(ds, bp->bio_bcount - bp->bio_resid,
(bp->bio_flags & BIO_ORDERED) ?
DEVSTAT_TAG_ORDERED : DEVSTAT_TAG_SIMPLE, flg);
}
/*
* This is the sysctl handler for the devstat package. The data pushed out
* on the kern.devstat.all sysctl variable consists of the current devstat
* generation number, and then an array of devstat structures, one for each
* device in the system.
*
* I'm really not too fond of this method of doing things, but there really
* aren't that many alternatives. We must have some method of making sure
* that the generation number the user gets corresponds with the data the
* user gets. If the user makes a separate sysctl call to get the
* generation, and then a sysctl call to get the device statistics, the
* device list could have changed in that brief period of time. By
* supplying the generation number along with the statistics output, we can
* guarantee that the generation number and the statistics match up.
*/
static int
sysctl_devstat(SYSCTL_HANDLER_ARGS)
{
int error, i;
struct devstat *nds;
struct devstatlist *devstat_head;
if (devstat_num_devs == 0)
return(EINVAL);
error = 0;
devstat_head = &device_statq;
/*
* First push out the generation number.
*/
error = SYSCTL_OUT(req, &devstat_generation, sizeof(long));
/*
* Now push out all the devices.
*/
for (i = 0, nds = STAILQ_FIRST(devstat_head);
(nds != NULL) && (i < devstat_num_devs) && (error == 0);
nds = STAILQ_NEXT(nds, dev_links), i++)
error = SYSCTL_OUT(req, nds, sizeof(struct devstat));
return(error);
}
/*
* Sysctl entries for devstat. The first one is a node that all the rest
* hang off of.
*/
SYSCTL_NODE(_kern, OID_AUTO, devstat, CTLFLAG_RD, 0, "Device Statistics");
SYSCTL_PROC(_kern_devstat, OID_AUTO, all, CTLFLAG_RD|CTLTYPE_OPAQUE,
0, 0, sysctl_devstat, "S,devstat", "All devices in the devstat list");
/*
* Export the number of devices in the system so that userland utilities
* can determine how much memory to allocate to hold all the devices.
*/
SYSCTL_INT(_kern_devstat, OID_AUTO, numdevs, CTLFLAG_RD,
&devstat_num_devs, 0, "Number of devices in the devstat list");
SYSCTL_LONG(_kern_devstat, OID_AUTO, generation, CTLFLAG_RD,
&devstat_generation, 0, "Devstat list generation");
SYSCTL_INT(_kern_devstat, OID_AUTO, version, CTLFLAG_RD,
&devstat_version, 0, "Devstat list version number");
