spl-proc: remove old taskq stats

These had minimal useful information for the admin, didn't work properly
in some places, and knew far too much about taskq internals.

With the new stats available, these should never be needed anymore.

Reviewed-by: Alexander Motin <[email protected]>
Reviewed-by: Brian Behlendorf <[email protected]>
Reviewed-by: Tino Reichardt <[email protected]>
Signed-off-by: Rob Norris <[email protected]>
Sponsored-by: Klara, Inc.
Sponsored-by: Syneto
Closes #16171

2 files changed, 0 insertions, 279 deletions

diff --git a/man/man4/spl.4 b/man/man4/spl.4
index 5cc12764e..22832c492 100644
--- a/man/man4/spl.4
+++ b/man/man4/spl.4
@@ -175,17 +175,6 @@ Increasing this value will
 result in a slower thread creation rate which may be preferable for some
 configurations.
 .
-.It Sy spl_max_show_tasks Ns = Ns Sy 512 Pq uint
-The maximum number of tasks per pending list in each taskq shown in
-.Pa /proc/spl/taskq{,-all} .
-Write
-.Sy 0
-to turn off the limit.
-The proc file will walk the lists with lock held,
-reading it could cause a lock-up if the list grow too large
-without limiting the output.
-"(truncated)" will be shown if the list is larger than the limit.
-.
 .It Sy spl_taskq_thread_timeout_ms Ns = Ns Sy 5000 Pq uint
 Minimum idle threads exit interval for dynamic taskqs.
 Smaller values allow idle threads exit more often and potentially be
diff --git a/module/os/linux/spl/spl-proc.c b/module/os/linux/spl/spl-proc.c
index 2c0cdd9fe..9fefcd03c 100644
--- a/module/os/linux/spl/spl-proc.c
+++ b/module/os/linux/spl/spl-proc.c
@@ -31,7 +31,6 @@
 #include <sys/kmem.h>
 #include <sys/kmem_cache.h>
 #include <sys/vmem.h>
-#include <sys/taskq.h>
 #include <sys/proc.h>
 #include <linux/ctype.h>
 #include <linux/kmod.h>
@@ -63,8 +62,6 @@ static struct ctl_table_header *spl_kstat = NULL;
 static struct proc_dir_entry *proc_spl = NULL;
 static struct proc_dir_entry *proc_spl_kmem = NULL;
 static struct proc_dir_entry *proc_spl_kmem_slab = NULL;
-static struct proc_dir_entry *proc_spl_taskq_all = NULL;
-static struct proc_dir_entry *proc_spl_taskq = NULL;
 struct proc_dir_entry *proc_spl_kstat = NULL;
 
 #ifdef DEBUG_KMEM
@@ -178,195 +175,6 @@ proc_dohostid(CONST_CTL_TABLE *table, int write,
 }
 
 static void
-taskq_seq_show_headers(struct seq_file *f)
-{
-	seq_printf(f, "%-25s %5s %5s %5s %5s %5s %5s %12s %5s %10s\n",
-	    "taskq", "act", "nthr", "spwn", "maxt", "pri",
-	    "mina", "maxa", "cura", "flags");
-}
-
-/* indices into the lheads array below */
-#define	LHEAD_PEND	0
-#define	LHEAD_PRIO	1
-#define	LHEAD_DELAY	2
-#define	LHEAD_WAIT	3
-#define	LHEAD_ACTIVE	4
-#define	LHEAD_SIZE	5
-
-static unsigned int spl_max_show_tasks = 512;
-/* CSTYLED */
-module_param(spl_max_show_tasks, uint, 0644);
-MODULE_PARM_DESC(spl_max_show_tasks, "Max number of tasks shown in taskq proc");
-
-static int
-taskq_seq_show_impl(struct seq_file *f, void *p, boolean_t allflag)
-{
-	taskq_t *tq = p;
-	taskq_thread_t *tqt = NULL;
-	spl_wait_queue_entry_t *wq;
-	struct task_struct *tsk;
-	taskq_ent_t *tqe;
-	char name[100];
-	struct list_head *lheads[LHEAD_SIZE], *lh;
-	static char *list_names[LHEAD_SIZE] =
-	    {"pend", "prio", "delay", "wait", "active" };
-	int i, j, have_lheads = 0;
-	unsigned long wflags, flags;
-
-	spin_lock_irqsave_nested(&tq->tq_lock, flags, tq->tq_lock_class);
-	spin_lock_irqsave(&tq->tq_wait_waitq.lock, wflags);
-
-	/* get the various lists and check whether they're empty */
-	lheads[LHEAD_PEND] = &tq->tq_pend_list;
-	lheads[LHEAD_PRIO] = &tq->tq_prio_list;
-	lheads[LHEAD_DELAY] = &tq->tq_delay_list;
-#ifdef HAVE_WAIT_QUEUE_HEAD_ENTRY
-	lheads[LHEAD_WAIT] = &tq->tq_wait_waitq.head;
-#else
-	lheads[LHEAD_WAIT] = &tq->tq_wait_waitq.task_list;
-#endif
-	lheads[LHEAD_ACTIVE] = &tq->tq_active_list;
-
-	for (i = 0; i < LHEAD_SIZE; ++i) {
-		if (list_empty(lheads[i]))
-			lheads[i] = NULL;
-		else
-			++have_lheads;
-	}
-
-	/* early return in non-"all" mode if lists are all empty */
-	if (!allflag && !have_lheads) {
-		spin_unlock_irqrestore(&tq->tq_wait_waitq.lock, wflags);
-		spin_unlock_irqrestore(&tq->tq_lock, flags);
-		return (0);
-	}
-
-	/* unlock the waitq quickly */
-	if (!lheads[LHEAD_WAIT])
-		spin_unlock_irqrestore(&tq->tq_wait_waitq.lock, wflags);
-
-	/* show the base taskq contents */
-	snprintf(name, sizeof (name), "%s/%d", tq->tq_name, tq->tq_instance);
-	seq_printf(f, "%-25s ", name);
-	seq_printf(f, "%5d %5d %5d %5d %5d %5d %12d %5d %10x\n",
-	    tq->tq_nactive, tq->tq_nthreads, tq->tq_nspawn,
-	    tq->tq_maxthreads, tq->tq_pri, tq->tq_minalloc, tq->tq_maxalloc,
-	    tq->tq_nalloc, tq->tq_flags);
-
-	/* show the active list */
-	if (lheads[LHEAD_ACTIVE]) {
-		j = 0;
-		list_for_each_entry(tqt, &tq->tq_active_list, tqt_active_list) {
-			if (j == 0)
-				seq_printf(f, "\t%s:",
-				    list_names[LHEAD_ACTIVE]);
-			else if (j == 2) {
-				seq_printf(f, "\n\t       ");
-				j = 0;
-			}
-			seq_printf(f, " [%d]%pf(%ps)",
-			    tqt->tqt_thread->pid,
-			    tqt->tqt_task->tqent_func,
-			    tqt->tqt_task->tqent_arg);
-			++j;
-		}
-		seq_printf(f, "\n");
-	}
-
-	for (i = LHEAD_PEND; i <= LHEAD_WAIT; ++i)
-		if (lheads[i]) {
-			j = 0;
-			list_for_each(lh, lheads[i]) {
-				if (spl_max_show_tasks != 0 &&
-				    j >= spl_max_show_tasks) {
-					seq_printf(f, "\n\t(truncated)");
-					break;
-				}
-				/* show the wait waitq list */
-				if (i == LHEAD_WAIT) {
-#ifdef HAVE_WAIT_QUEUE_HEAD_ENTRY
-					wq = list_entry(lh,
-					    spl_wait_queue_entry_t, entry);
-#else
-					wq = list_entry(lh,
-					    spl_wait_queue_entry_t, task_list);
-#endif
-					if (j == 0)
-						seq_printf(f, "\t%s:",
-						    list_names[i]);
-					else if (j % 8 == 0)
-						seq_printf(f, "\n\t     ");
-
-					tsk = wq->private;
-					seq_printf(f, " %d", tsk->pid);
-				/* pend, prio and delay lists */
-				} else {
-					tqe = list_entry(lh, taskq_ent_t,
-					    tqent_list);
-					if (j == 0)
-						seq_printf(f, "\t%s:",
-						    list_names[i]);
-					else if (j % 2 == 0)
-						seq_printf(f, "\n\t     ");
-
-					seq_printf(f, " %pf(%ps)",
-					    tqe->tqent_func,
-					    tqe->tqent_arg);
-				}
-				++j;
-			}
-			seq_printf(f, "\n");
-		}
-	if (lheads[LHEAD_WAIT])
-		spin_unlock_irqrestore(&tq->tq_wait_waitq.lock, wflags);
-	spin_unlock_irqrestore(&tq->tq_lock, flags);
-
-	return (0);
-}
-
-static int
-taskq_all_seq_show(struct seq_file *f, void *p)
-{
-	return (taskq_seq_show_impl(f, p, B_TRUE));
-}
-
-static int
-taskq_seq_show(struct seq_file *f, void *p)
-{
-	return (taskq_seq_show_impl(f, p, B_FALSE));
-}
-
-static void *
-taskq_seq_start(struct seq_file *f, loff_t *pos)
-{
-	struct list_head *p;
-	loff_t n = *pos;
-
-	down_read(&tq_list_sem);
-	if (!n)
-		taskq_seq_show_headers(f);
-
-	p = tq_list.next;
-	while (n--) {
-		p = p->next;
-		if (p == &tq_list)
-		return (NULL);
-	}
-
-	return (list_entry(p, taskq_t, tq_taskqs));
-}
-
-static void *
-taskq_seq_next(struct seq_file *f, void *p, loff_t *pos)
-{
-	taskq_t *tq = p;
-
-	++*pos;
-	return ((tq->tq_taskqs.next == &tq_list) ?
-	    NULL : list_entry(tq->tq_taskqs.next, taskq_t, tq_taskqs));
-}
-
-static void
 slab_seq_show_headers(struct seq_file *f)
 {
 	seq_printf(f,
@@ -501,66 +309,6 @@ static const kstat_proc_op_t proc_slab_operations = {
 #endif
 };
 
-static void
-taskq_seq_stop(struct seq_file *f, void *v)
-{
-	up_read(&tq_list_sem);
-}
-
-static const struct seq_operations taskq_all_seq_ops = {
-	.show	= taskq_all_seq_show,
-	.start	= taskq_seq_start,
-	.next	= taskq_seq_next,
-	.stop	= taskq_seq_stop,
-};
-
-static const struct seq_operations taskq_seq_ops = {
-	.show	= taskq_seq_show,
-	.start	= taskq_seq_start,
-	.next	= taskq_seq_next,
-	.stop	= taskq_seq_stop,
-};
-
-static int
-proc_taskq_all_open(struct inode *inode, struct file *filp)
-{
-	return (seq_open(filp, &taskq_all_seq_ops));
-}
-
-static int
-proc_taskq_open(struct inode *inode, struct file *filp)
-{
-	return (seq_open(filp, &taskq_seq_ops));
-}
-
-static const kstat_proc_op_t proc_taskq_all_operations = {
-#ifdef HAVE_PROC_OPS_STRUCT
-	.proc_open	= proc_taskq_all_open,
-	.proc_read	= seq_read,
-	.proc_lseek	= seq_lseek,
-	.proc_release	= seq_release,
-#else
-	.open		= proc_taskq_all_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= seq_release,
-#endif
-};
-
-static const kstat_proc_op_t proc_taskq_operations = {
-#ifdef HAVE_PROC_OPS_STRUCT
-	.proc_open	= proc_taskq_open,
-	.proc_read	= seq_read,
-	.proc_lseek	= seq_lseek,
-	.proc_release	= seq_release,
-#else
-	.open		= proc_taskq_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= seq_release,
-#endif
-};
-
 static struct ctl_table spl_kmem_table[] = {
 #ifdef DEBUG_KMEM
 	{
@@ -677,8 +425,6 @@ static void spl_proc_cleanup(void)
 	remove_proc_entry("kstat", proc_spl);
 	remove_proc_entry("slab", proc_spl_kmem);
 	remove_proc_entry("kmem", proc_spl);
-	remove_proc_entry("taskq-all", proc_spl);
-	remove_proc_entry("taskq", proc_spl);
 	remove_proc_entry("spl", NULL);
 
 #ifndef HAVE_REGISTER_SYSCTL_TABLE
@@ -761,20 +507,6 @@ spl_proc_init(void)
 		goto out;
 	}
 
-	proc_spl_taskq_all = proc_create_data("taskq-all", 0444, proc_spl,
-	    &proc_taskq_all_operations, NULL);
-	if (proc_spl_taskq_all == NULL) {
-		rc = -EUNATCH;
-		goto out;
-	}
-
-	proc_spl_taskq = proc_create_data("taskq", 0444, proc_spl,
-	    &proc_taskq_operations, NULL);
-	if (proc_spl_taskq == NULL) {
-		rc = -EUNATCH;
-		goto out;
-	}
-
 	proc_spl_kmem = proc_mkdir("kmem", proc_spl);
 	if (proc_spl_kmem == NULL) {
 		rc = -EUNATCH;