From 72a2f3b5e28ada60de01f08b28888f70eec0baed Mon Sep 17 00:00:00 2001
From: Michal Meloun <mmel@FreeBSD.org>
Date: Fri, 24 Dec 2021 08:38:32 +0100
Subject: [PATCH] extres/clk: Improve sysctl dump of clocks.

Always recalculate the frequency, the cache is lazily initialized so it is not always up to date.
While I'm in mark sysctl as MPSAFE.

Discussed with:	manu, adrian
MFC after:	1 week
---
 sys/dev/extres/clk/clk.c | 26 +++++++++++++++++++-------
 1 file changed, 19 insertions(+), 7 deletions(-)

diff --git a/sys/dev/extres/clk/clk.c b/sys/dev/extres/clk/clk.c
index b1522eb1d4c..839f0f842a7 100644
--- a/sys/dev/extres/clk/clk.c
+++ b/sys/dev/extres/clk/clk.c
@@ -185,6 +185,7 @@ enum clknode_sysctl_type {
 	CLKNODE_SYSCTL_PARENT,
 	CLKNODE_SYSCTL_PARENTS_LIST,
 	CLKNODE_SYSCTL_CHILDREN_LIST,
+	CLKNODE_SYSCTL_FREQUENCY,
 };
 
 static int clknode_sysctl(SYSCTL_HANDLER_ARGS);
@@ -403,7 +404,7 @@ clkdom_create(device_t dev)
 	SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),
 	    OID_AUTO, "clocks",
-	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
+	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
 	    clkdom, 0, clkdom_sysctl, "A",
 	    "Clock list for the domain");
 
@@ -624,7 +625,7 @@ clknode_create(struct clkdom * clkdom, clknode_class_t clknode_class,
 	clknode->parent_idx = CLKNODE_IDX_NONE;
 
 	if (replaced)
-			return (clknode);
+		return (clknode);
 
 	sysctl_ctx_init(&clknode->sysctl_ctx);
 	clknode_oid = SYSCTL_ADD_NODE(&clknode->sysctl_ctx,
@@ -632,28 +633,31 @@ clknode_create(struct clkdom * clkdom, clknode_class_t clknode_class,
 	    OID_AUTO, clknode->name,
 	    CTLFLAG_RD | CTLFLAG_MPSAFE, 0, "A clock node");
 
-	SYSCTL_ADD_U64(&clknode->sysctl_ctx,
+	SYSCTL_ADD_PROC(&clknode->sysctl_ctx,
 	    SYSCTL_CHILDREN(clknode_oid),
 	    OID_AUTO, "frequency",
-	    CTLFLAG_RD, &clknode->freq, 0, "The clock frequency");
+	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
+	    clknode, CLKNODE_SYSCTL_FREQUENCY, clknode_sysctl,
+	    "A",
+	    "The clock frequency");
 	SYSCTL_ADD_PROC(&clknode->sysctl_ctx,
 	    SYSCTL_CHILDREN(clknode_oid),
 	    OID_AUTO, "parent",
-	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
+	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
 	    clknode, CLKNODE_SYSCTL_PARENT, clknode_sysctl,
 	    "A",
 	    "The clock parent");
 	SYSCTL_ADD_PROC(&clknode->sysctl_ctx,
 	    SYSCTL_CHILDREN(clknode_oid),
 	    OID_AUTO, "parents",
-	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
+	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
 	    clknode, CLKNODE_SYSCTL_PARENTS_LIST, clknode_sysctl,
 	    "A",
 	    "The clock parents list");
 	SYSCTL_ADD_PROC(&clknode->sysctl_ctx,
 	    SYSCTL_CHILDREN(clknode_oid),
 	    OID_AUTO, "childrens",
-	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
+	    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
 	    clknode, CLKNODE_SYSCTL_CHILDREN_LIST, clknode_sysctl,
 	    "A",
 	    "The clock childrens list");
@@ -1612,6 +1616,7 @@ clknode_sysctl(SYSCTL_HANDLER_ARGS)
 	enum clknode_sysctl_type type = arg2;
 	struct sbuf *sb;
 	const char **parent_names;
+	uint64_t freq;
 	int ret, i;
 
 	clknode = arg1;
@@ -1635,6 +1640,13 @@ clknode_sysctl(SYSCTL_HANDLER_ARGS)
 			sbuf_printf(sb, "%s ", children->name);
 		}
 		break;
+	case CLKNODE_SYSCTL_FREQUENCY:
+		ret = clknode_get_freq(clknode, &freq);
+		if (ret == 0)
+			sbuf_printf(sb, "%ju ", (uintmax_t)freq);
+		else
+			sbuf_printf(sb, "Error: %d ", ret);
+		break;
 	}
 	CLK_TOPO_UNLOCK();