mirror_zfs/module/os/linux/spl/spl-kstat.c
Brian Behlendorf 46c71074ca Replace ZFS on Linux references with OpenZFS
This change updates the documentation to refer to the project
as OpenZFS instead ZFS on Linux.  Web links have been updated
to refer to https://github.com/openzfs/zfs.  The extraneous
zfsonlinux.org web links in the ZED and SPL sources have been
dropped.

Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #11007
2020-10-16 13:01:24 -07:00

782 lines
18 KiB
C

/*
* Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC.
* Copyright (C) 2007 The Regents of the University of California.
* Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
* Written by Brian Behlendorf <behlendorf1@llnl.gov>.
* UCRL-CODE-235197
*
* This file is part of the SPL, Solaris Porting Layer.
*
* The SPL is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* The SPL 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.
*
* You should have received a copy of the GNU General Public License along
* with the SPL. If not, see <http://www.gnu.org/licenses/>.
*
* Solaris Porting Layer (SPL) Kstat Implementation.
*
* Links to Illumos.org for more information on kstat function:
* [1] https://illumos.org/man/1M/kstat
* [2] https://illumos.org/man/9f/kstat_create
*/
#include <linux/seq_file.h>
#include <sys/kstat.h>
#include <sys/vmem.h>
#include <sys/cmn_err.h>
#include <sys/sysmacros.h>
static kmutex_t kstat_module_lock;
static struct list_head kstat_module_list;
static kid_t kstat_id;
static int
kstat_resize_raw(kstat_t *ksp)
{
if (ksp->ks_raw_bufsize == KSTAT_RAW_MAX)
return (ENOMEM);
vmem_free(ksp->ks_raw_buf, ksp->ks_raw_bufsize);
ksp->ks_raw_bufsize = MIN(ksp->ks_raw_bufsize * 2, KSTAT_RAW_MAX);
ksp->ks_raw_buf = vmem_alloc(ksp->ks_raw_bufsize, KM_SLEEP);
return (0);
}
void
kstat_waitq_enter(kstat_io_t *kiop)
{
hrtime_t new, delta;
ulong_t wcnt;
new = gethrtime();
delta = new - kiop->wlastupdate;
kiop->wlastupdate = new;
wcnt = kiop->wcnt++;
if (wcnt != 0) {
kiop->wlentime += delta * wcnt;
kiop->wtime += delta;
}
}
EXPORT_SYMBOL(kstat_waitq_enter);
void
kstat_waitq_exit(kstat_io_t *kiop)
{
hrtime_t new, delta;
ulong_t wcnt;
new = gethrtime();
delta = new - kiop->wlastupdate;
kiop->wlastupdate = new;
wcnt = kiop->wcnt--;
ASSERT((int)wcnt > 0);
kiop->wlentime += delta * wcnt;
kiop->wtime += delta;
}
EXPORT_SYMBOL(kstat_waitq_exit);
void
kstat_runq_enter(kstat_io_t *kiop)
{
hrtime_t new, delta;
ulong_t rcnt;
new = gethrtime();
delta = new - kiop->rlastupdate;
kiop->rlastupdate = new;
rcnt = kiop->rcnt++;
if (rcnt != 0) {
kiop->rlentime += delta * rcnt;
kiop->rtime += delta;
}
}
EXPORT_SYMBOL(kstat_runq_enter);
void
kstat_runq_exit(kstat_io_t *kiop)
{
hrtime_t new, delta;
ulong_t rcnt;
new = gethrtime();
delta = new - kiop->rlastupdate;
kiop->rlastupdate = new;
rcnt = kiop->rcnt--;
ASSERT((int)rcnt > 0);
kiop->rlentime += delta * rcnt;
kiop->rtime += delta;
}
EXPORT_SYMBOL(kstat_runq_exit);
static int
kstat_seq_show_headers(struct seq_file *f)
{
kstat_t *ksp = (kstat_t *)f->private;
int rc = 0;
ASSERT(ksp->ks_magic == KS_MAGIC);
seq_printf(f, "%d %d 0x%02x %d %d %lld %lld\n",
ksp->ks_kid, ksp->ks_type, ksp->ks_flags,
ksp->ks_ndata, (int)ksp->ks_data_size,
ksp->ks_crtime, ksp->ks_snaptime);
switch (ksp->ks_type) {
case KSTAT_TYPE_RAW:
restart:
if (ksp->ks_raw_ops.headers) {
rc = ksp->ks_raw_ops.headers(
ksp->ks_raw_buf, ksp->ks_raw_bufsize);
if (rc == ENOMEM && !kstat_resize_raw(ksp))
goto restart;
if (!rc)
seq_puts(f, ksp->ks_raw_buf);
} else {
seq_printf(f, "raw data\n");
}
break;
case KSTAT_TYPE_NAMED:
seq_printf(f, "%-31s %-4s %s\n",
"name", "type", "data");
break;
case KSTAT_TYPE_INTR:
seq_printf(f, "%-8s %-8s %-8s %-8s %-8s\n",
"hard", "soft", "watchdog",
"spurious", "multsvc");
break;
case KSTAT_TYPE_IO:
seq_printf(f,
"%-8s %-8s %-8s %-8s %-8s %-8s "
"%-8s %-8s %-8s %-8s %-8s %-8s\n",
"nread", "nwritten", "reads", "writes",
"wtime", "wlentime", "wupdate",
"rtime", "rlentime", "rupdate",
"wcnt", "rcnt");
break;
case KSTAT_TYPE_TIMER:
seq_printf(f,
"%-31s %-8s "
"%-8s %-8s %-8s %-8s %-8s\n",
"name", "events", "elapsed",
"min", "max", "start", "stop");
break;
default:
PANIC("Undefined kstat type %d\n", ksp->ks_type);
}
return (-rc);
}
static int
kstat_seq_show_raw(struct seq_file *f, unsigned char *p, int l)
{
int i, j;
for (i = 0; ; i++) {
seq_printf(f, "%03x:", i);
for (j = 0; j < 16; j++) {
if (i * 16 + j >= l) {
seq_printf(f, "\n");
goto out;
}
seq_printf(f, " %02x", (unsigned char)p[i * 16 + j]);
}
seq_printf(f, "\n");
}
out:
return (0);
}
static int
kstat_seq_show_named(struct seq_file *f, kstat_named_t *knp)
{
seq_printf(f, "%-31s %-4d ", knp->name, knp->data_type);
switch (knp->data_type) {
case KSTAT_DATA_CHAR:
knp->value.c[15] = '\0'; /* NULL terminate */
seq_printf(f, "%-16s", knp->value.c);
break;
/*
* NOTE - We need to be more careful able what tokens are
* used for each arch, for now this is correct for x86_64.
*/
case KSTAT_DATA_INT32:
seq_printf(f, "%d", knp->value.i32);
break;
case KSTAT_DATA_UINT32:
seq_printf(f, "%u", knp->value.ui32);
break;
case KSTAT_DATA_INT64:
seq_printf(f, "%lld", (signed long long)knp->value.i64);
break;
case KSTAT_DATA_UINT64:
seq_printf(f, "%llu",
(unsigned long long)knp->value.ui64);
break;
case KSTAT_DATA_LONG:
seq_printf(f, "%ld", knp->value.l);
break;
case KSTAT_DATA_ULONG:
seq_printf(f, "%lu", knp->value.ul);
break;
case KSTAT_DATA_STRING:
KSTAT_NAMED_STR_PTR(knp)
[KSTAT_NAMED_STR_BUFLEN(knp)-1] = '\0';
seq_printf(f, "%s", KSTAT_NAMED_STR_PTR(knp));
break;
default:
PANIC("Undefined kstat data type %d\n", knp->data_type);
}
seq_printf(f, "\n");
return (0);
}
static int
kstat_seq_show_intr(struct seq_file *f, kstat_intr_t *kip)
{
seq_printf(f, "%-8u %-8u %-8u %-8u %-8u\n",
kip->intrs[KSTAT_INTR_HARD],
kip->intrs[KSTAT_INTR_SOFT],
kip->intrs[KSTAT_INTR_WATCHDOG],
kip->intrs[KSTAT_INTR_SPURIOUS],
kip->intrs[KSTAT_INTR_MULTSVC]);
return (0);
}
static int
kstat_seq_show_io(struct seq_file *f, kstat_io_t *kip)
{
/* though wlentime & friends are signed, they will never be negative */
seq_printf(f,
"%-8llu %-8llu %-8u %-8u %-8llu %-8llu "
"%-8llu %-8llu %-8llu %-8llu %-8u %-8u\n",
kip->nread, kip->nwritten,
kip->reads, kip->writes,
kip->wtime, kip->wlentime, kip->wlastupdate,
kip->rtime, kip->rlentime, kip->rlastupdate,
kip->wcnt, kip->rcnt);
return (0);
}
static int
kstat_seq_show_timer(struct seq_file *f, kstat_timer_t *ktp)
{
seq_printf(f,
"%-31s %-8llu %-8llu %-8llu %-8llu %-8llu %-8llu\n",
ktp->name, ktp->num_events, ktp->elapsed_time,
ktp->min_time, ktp->max_time,
ktp->start_time, ktp->stop_time);
return (0);
}
static int
kstat_seq_show(struct seq_file *f, void *p)
{
kstat_t *ksp = (kstat_t *)f->private;
int rc = 0;
ASSERT(ksp->ks_magic == KS_MAGIC);
switch (ksp->ks_type) {
case KSTAT_TYPE_RAW:
restart:
if (ksp->ks_raw_ops.data) {
rc = ksp->ks_raw_ops.data(
ksp->ks_raw_buf, ksp->ks_raw_bufsize, p);
if (rc == ENOMEM && !kstat_resize_raw(ksp))
goto restart;
if (!rc)
seq_puts(f, ksp->ks_raw_buf);
} else {
ASSERT(ksp->ks_ndata == 1);
rc = kstat_seq_show_raw(f, ksp->ks_data,
ksp->ks_data_size);
}
break;
case KSTAT_TYPE_NAMED:
rc = kstat_seq_show_named(f, (kstat_named_t *)p);
break;
case KSTAT_TYPE_INTR:
rc = kstat_seq_show_intr(f, (kstat_intr_t *)p);
break;
case KSTAT_TYPE_IO:
rc = kstat_seq_show_io(f, (kstat_io_t *)p);
break;
case KSTAT_TYPE_TIMER:
rc = kstat_seq_show_timer(f, (kstat_timer_t *)p);
break;
default:
PANIC("Undefined kstat type %d\n", ksp->ks_type);
}
return (-rc);
}
static int
kstat_default_update(kstat_t *ksp, int rw)
{
ASSERT(ksp != NULL);
if (rw == KSTAT_WRITE)
return (EACCES);
return (0);
}
static void *
kstat_seq_data_addr(kstat_t *ksp, loff_t n)
{
void *rc = NULL;
switch (ksp->ks_type) {
case KSTAT_TYPE_RAW:
if (ksp->ks_raw_ops.addr)
rc = ksp->ks_raw_ops.addr(ksp, n);
else
rc = ksp->ks_data;
break;
case KSTAT_TYPE_NAMED:
rc = ksp->ks_data + n * sizeof (kstat_named_t);
break;
case KSTAT_TYPE_INTR:
rc = ksp->ks_data + n * sizeof (kstat_intr_t);
break;
case KSTAT_TYPE_IO:
rc = ksp->ks_data + n * sizeof (kstat_io_t);
break;
case KSTAT_TYPE_TIMER:
rc = ksp->ks_data + n * sizeof (kstat_timer_t);
break;
default:
PANIC("Undefined kstat type %d\n", ksp->ks_type);
}
return (rc);
}
static void *
kstat_seq_start(struct seq_file *f, loff_t *pos)
{
loff_t n = *pos;
kstat_t *ksp = (kstat_t *)f->private;
ASSERT(ksp->ks_magic == KS_MAGIC);
mutex_enter(ksp->ks_lock);
if (ksp->ks_type == KSTAT_TYPE_RAW) {
ksp->ks_raw_bufsize = PAGE_SIZE;
ksp->ks_raw_buf = vmem_alloc(ksp->ks_raw_bufsize, KM_SLEEP);
}
/* Dynamically update kstat, on error existing kstats are used */
(void) ksp->ks_update(ksp, KSTAT_READ);
ksp->ks_snaptime = gethrtime();
if (!(ksp->ks_flags & KSTAT_FLAG_NO_HEADERS) && !n &&
kstat_seq_show_headers(f))
return (NULL);
if (n >= ksp->ks_ndata)
return (NULL);
return (kstat_seq_data_addr(ksp, n));
}
static void *
kstat_seq_next(struct seq_file *f, void *p, loff_t *pos)
{
kstat_t *ksp = (kstat_t *)f->private;
ASSERT(ksp->ks_magic == KS_MAGIC);
++*pos;
if (*pos >= ksp->ks_ndata)
return (NULL);
return (kstat_seq_data_addr(ksp, *pos));
}
static void
kstat_seq_stop(struct seq_file *f, void *v)
{
kstat_t *ksp = (kstat_t *)f->private;
ASSERT(ksp->ks_magic == KS_MAGIC);
if (ksp->ks_type == KSTAT_TYPE_RAW)
vmem_free(ksp->ks_raw_buf, ksp->ks_raw_bufsize);
mutex_exit(ksp->ks_lock);
}
static struct seq_operations kstat_seq_ops = {
.show = kstat_seq_show,
.start = kstat_seq_start,
.next = kstat_seq_next,
.stop = kstat_seq_stop,
};
static kstat_module_t *
kstat_find_module(char *name)
{
kstat_module_t *module = NULL;
list_for_each_entry(module, &kstat_module_list, ksm_module_list) {
if (strncmp(name, module->ksm_name, KSTAT_STRLEN) == 0)
return (module);
}
return (NULL);
}
static kstat_module_t *
kstat_create_module(char *name)
{
kstat_module_t *module;
struct proc_dir_entry *pde;
pde = proc_mkdir(name, proc_spl_kstat);
if (pde == NULL)
return (NULL);
module = kmem_alloc(sizeof (kstat_module_t), KM_SLEEP);
module->ksm_proc = pde;
strlcpy(module->ksm_name, name, KSTAT_STRLEN+1);
INIT_LIST_HEAD(&module->ksm_kstat_list);
list_add_tail(&module->ksm_module_list, &kstat_module_list);
return (module);
}
static void
kstat_delete_module(kstat_module_t *module)
{
ASSERT(list_empty(&module->ksm_kstat_list));
remove_proc_entry(module->ksm_name, proc_spl_kstat);
list_del(&module->ksm_module_list);
kmem_free(module, sizeof (kstat_module_t));
}
static int
proc_kstat_open(struct inode *inode, struct file *filp)
{
struct seq_file *f;
int rc;
rc = seq_open(filp, &kstat_seq_ops);
if (rc)
return (rc);
f = filp->private_data;
f->private = PDE_DATA(inode);
return (rc);
}
static ssize_t
proc_kstat_write(struct file *filp, const char __user *buf, size_t len,
loff_t *ppos)
{
struct seq_file *f = filp->private_data;
kstat_t *ksp = f->private;
int rc;
ASSERT(ksp->ks_magic == KS_MAGIC);
mutex_enter(ksp->ks_lock);
rc = ksp->ks_update(ksp, KSTAT_WRITE);
mutex_exit(ksp->ks_lock);
if (rc)
return (-rc);
*ppos += len;
return (len);
}
static const kstat_proc_op_t proc_kstat_operations = {
#ifdef HAVE_PROC_OPS_STRUCT
.proc_open = proc_kstat_open,
.proc_write = proc_kstat_write,
.proc_read = seq_read,
.proc_lseek = seq_lseek,
.proc_release = seq_release,
#else
.open = proc_kstat_open,
.write = proc_kstat_write,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
#endif
};
void
__kstat_set_raw_ops(kstat_t *ksp,
int (*headers)(char *buf, size_t size),
int (*data)(char *buf, size_t size, void *data),
void *(*addr)(kstat_t *ksp, loff_t index))
{
ksp->ks_raw_ops.headers = headers;
ksp->ks_raw_ops.data = data;
ksp->ks_raw_ops.addr = addr;
}
EXPORT_SYMBOL(__kstat_set_raw_ops);
void
kstat_proc_entry_init(kstat_proc_entry_t *kpep, const char *module,
const char *name)
{
kpep->kpe_owner = NULL;
kpep->kpe_proc = NULL;
INIT_LIST_HEAD(&kpep->kpe_list);
strncpy(kpep->kpe_module, module, KSTAT_STRLEN);
strncpy(kpep->kpe_name, name, KSTAT_STRLEN);
}
EXPORT_SYMBOL(kstat_proc_entry_init);
kstat_t *
__kstat_create(const char *ks_module, int ks_instance, const char *ks_name,
const char *ks_class, uchar_t ks_type, uint_t ks_ndata,
uchar_t ks_flags)
{
kstat_t *ksp;
ASSERT(ks_module);
ASSERT(ks_instance == 0);
ASSERT(ks_name);
if ((ks_type == KSTAT_TYPE_INTR) || (ks_type == KSTAT_TYPE_IO))
ASSERT(ks_ndata == 1);
ksp = kmem_zalloc(sizeof (*ksp), KM_SLEEP);
if (ksp == NULL)
return (ksp);
mutex_enter(&kstat_module_lock);
ksp->ks_kid = kstat_id;
kstat_id++;
mutex_exit(&kstat_module_lock);
ksp->ks_magic = KS_MAGIC;
mutex_init(&ksp->ks_private_lock, NULL, MUTEX_DEFAULT, NULL);
ksp->ks_lock = &ksp->ks_private_lock;
ksp->ks_crtime = gethrtime();
ksp->ks_snaptime = ksp->ks_crtime;
ksp->ks_instance = ks_instance;
strncpy(ksp->ks_class, ks_class, KSTAT_STRLEN);
ksp->ks_type = ks_type;
ksp->ks_flags = ks_flags;
ksp->ks_update = kstat_default_update;
ksp->ks_private = NULL;
ksp->ks_raw_ops.headers = NULL;
ksp->ks_raw_ops.data = NULL;
ksp->ks_raw_ops.addr = NULL;
ksp->ks_raw_buf = NULL;
ksp->ks_raw_bufsize = 0;
kstat_proc_entry_init(&ksp->ks_proc, ks_module, ks_name);
switch (ksp->ks_type) {
case KSTAT_TYPE_RAW:
ksp->ks_ndata = 1;
ksp->ks_data_size = ks_ndata;
break;
case KSTAT_TYPE_NAMED:
ksp->ks_ndata = ks_ndata;
ksp->ks_data_size = ks_ndata * sizeof (kstat_named_t);
break;
case KSTAT_TYPE_INTR:
ksp->ks_ndata = ks_ndata;
ksp->ks_data_size = ks_ndata * sizeof (kstat_intr_t);
break;
case KSTAT_TYPE_IO:
ksp->ks_ndata = ks_ndata;
ksp->ks_data_size = ks_ndata * sizeof (kstat_io_t);
break;
case KSTAT_TYPE_TIMER:
ksp->ks_ndata = ks_ndata;
ksp->ks_data_size = ks_ndata * sizeof (kstat_timer_t);
break;
default:
PANIC("Undefined kstat type %d\n", ksp->ks_type);
}
if (ksp->ks_flags & KSTAT_FLAG_VIRTUAL) {
ksp->ks_data = NULL;
} else {
ksp->ks_data = kmem_zalloc(ksp->ks_data_size, KM_SLEEP);
if (ksp->ks_data == NULL) {
kmem_free(ksp, sizeof (*ksp));
ksp = NULL;
}
}
return (ksp);
}
EXPORT_SYMBOL(__kstat_create);
static int
kstat_detect_collision(kstat_proc_entry_t *kpep)
{
kstat_module_t *module;
kstat_proc_entry_t *tmp = NULL;
char *parent;
char *cp;
parent = kmem_asprintf("%s", kpep->kpe_module);
if ((cp = strrchr(parent, '/')) == NULL) {
kmem_strfree(parent);
return (0);
}
cp[0] = '\0';
if ((module = kstat_find_module(parent)) != NULL) {
list_for_each_entry(tmp, &module->ksm_kstat_list, kpe_list) {
if (strncmp(tmp->kpe_name, cp+1, KSTAT_STRLEN) == 0) {
kmem_strfree(parent);
return (EEXIST);
}
}
}
kmem_strfree(parent);
return (0);
}
/*
* Add a file to the proc filesystem under the kstat namespace (i.e.
* /proc/spl/kstat/). The file need not necessarily be implemented as a
* kstat.
*/
void
kstat_proc_entry_install(kstat_proc_entry_t *kpep, mode_t mode,
const kstat_proc_op_t *proc_ops, void *data)
{
kstat_module_t *module;
kstat_proc_entry_t *tmp = NULL;
ASSERT(kpep);
mutex_enter(&kstat_module_lock);
module = kstat_find_module(kpep->kpe_module);
if (module == NULL) {
if (kstat_detect_collision(kpep) != 0) {
cmn_err(CE_WARN, "kstat_create('%s', '%s'): namespace" \
" collision", kpep->kpe_module, kpep->kpe_name);
goto out;
}
module = kstat_create_module(kpep->kpe_module);
if (module == NULL)
goto out;
}
/*
* Only one entry by this name per-module, on failure the module
* shouldn't be deleted because we know it has at least one entry.
*/
list_for_each_entry(tmp, &module->ksm_kstat_list, kpe_list) {
if (strncmp(tmp->kpe_name, kpep->kpe_name, KSTAT_STRLEN) == 0)
goto out;
}
list_add_tail(&kpep->kpe_list, &module->ksm_kstat_list);
kpep->kpe_owner = module;
kpep->kpe_proc = proc_create_data(kpep->kpe_name, mode,
module->ksm_proc, proc_ops, data);
if (kpep->kpe_proc == NULL) {
list_del_init(&kpep->kpe_list);
if (list_empty(&module->ksm_kstat_list))
kstat_delete_module(module);
}
out:
mutex_exit(&kstat_module_lock);
}
EXPORT_SYMBOL(kstat_proc_entry_install);
void
__kstat_install(kstat_t *ksp)
{
ASSERT(ksp);
mode_t mode;
/* Specify permission modes for different kstats */
if (strncmp(ksp->ks_proc.kpe_name, "dbufs", KSTAT_STRLEN) == 0) {
mode = 0600;
} else {
mode = 0644;
}
kstat_proc_entry_install(
&ksp->ks_proc, mode, &proc_kstat_operations, ksp);
}
EXPORT_SYMBOL(__kstat_install);
void
kstat_proc_entry_delete(kstat_proc_entry_t *kpep)
{
kstat_module_t *module = kpep->kpe_owner;
if (kpep->kpe_proc)
remove_proc_entry(kpep->kpe_name, module->ksm_proc);
mutex_enter(&kstat_module_lock);
list_del_init(&kpep->kpe_list);
/*
* Remove top level module directory if it wasn't empty before, but now
* is.
*/
if (kpep->kpe_proc && list_empty(&module->ksm_kstat_list))
kstat_delete_module(module);
mutex_exit(&kstat_module_lock);
}
EXPORT_SYMBOL(kstat_proc_entry_delete);
void
__kstat_delete(kstat_t *ksp)
{
kstat_proc_entry_delete(&ksp->ks_proc);
if (!(ksp->ks_flags & KSTAT_FLAG_VIRTUAL))
kmem_free(ksp->ks_data, ksp->ks_data_size);
ksp->ks_lock = NULL;
mutex_destroy(&ksp->ks_private_lock);
kmem_free(ksp, sizeof (*ksp));
}
EXPORT_SYMBOL(__kstat_delete);
int
spl_kstat_init(void)
{
mutex_init(&kstat_module_lock, NULL, MUTEX_DEFAULT, NULL);
INIT_LIST_HEAD(&kstat_module_list);
kstat_id = 0;
return (0);
}
void
spl_kstat_fini(void)
{
ASSERT(list_empty(&kstat_module_list));
mutex_destroy(&kstat_module_lock);
}