git: 20ca85c50d78 - stable/14 - net80211: improve scan debugging

From: Bjoern A. Zeeb <bz_at_FreeBSD.org>
Date: Wed, 04 Oct 2023 15:23:39 UTC
The branch stable/14 has been updated by bz:

URL: https://cgit.FreeBSD.org/src/commit/?id=20ca85c50d782dab4bf4306db4ac0e6164a42b53

commit 20ca85c50d782dab4bf4306db4ac0e6164a42b53
Author:     Bjoern A. Zeeb <bz@FreeBSD.org>
AuthorDate: 2023-09-14 17:36:29 +0000
Commit:     Bjoern A. Zeeb <bz@FreeBSD.org>
CommitDate: 2023-10-04 15:19:17 +0000

    net80211: improve scan debugging
    
    While debugging other problems I ran into the case where net80211
    was thinking a scan was ongoing and new scans could not be started
    but given other logging there was clearly no more scan running.
    It was hard after the fact to quickly determine enough state to
    reconstruct or validate assumptions.
    
    Improve a MSG_SCAN debug logging and implement _db_show_scan() ddb
    output which can be printed along with show com /S or /a.
    
    Sponsored by:   The FreeBSD Foundation
    
    (cherry picked from commit 33396ec29f1daae31f4738f0da98dce168ca73c6)
---
 sys/net80211/ieee80211_ddb.c   | 74 ++++++++++++++++++++++++++++++++++++++----
 sys/net80211/ieee80211_ioctl.c |  6 ++--
 sys/net80211/ieee80211_scan.h  |  6 +++-
 3 files changed, 77 insertions(+), 9 deletions(-)

diff --git a/sys/net80211/ieee80211_ddb.c b/sys/net80211/ieee80211_ddb.c
index 4e2df134c7a9..525814d202b1 100644
--- a/sys/net80211/ieee80211_ddb.c
+++ b/sys/net80211/ieee80211_ddb.c
@@ -67,7 +67,7 @@
 static void _db_show_sta(const struct ieee80211_node *);
 static void _db_show_vap(const struct ieee80211vap *, int, int);
 static void _db_show_com(const struct ieee80211com *,
-	int showvaps, int showsta, int showmesh, int showprocs);
+	int showvaps, int showsta, int showmesh, int showprocs, int);
 
 static void _db_show_all_vaps(void *, struct ieee80211com *);
 
@@ -132,7 +132,7 @@ DB_SHOW_COMMAND(vap, db_show_vap)
 DB_SHOW_COMMAND(com, db_show_com)
 {
 	const struct ieee80211com *ic;
-	int i, showprocs = 0, showvaps = 0, showsta = 0, showmesh = 0;
+	int i, showprocs = 0, showvaps = 0, showsta = 0, showmesh = 0, showscan = 0;
 
 	if (!have_addr) {
 		db_printf("usage: show com <addr>\n");
@@ -141,7 +141,10 @@ DB_SHOW_COMMAND(com, db_show_com)
 	for (i = 0; modif[i] != '\0'; i++)
 		switch (modif[i]) {
 		case 'a':
-			showsta = showmesh = showvaps = showprocs = 1;
+			showsta = showmesh = showvaps = showprocs = showscan = 1;
+			break;
+		case 'S':
+			showscan = 1;
 			break;
 		case 's':
 			showsta = 1;
@@ -158,7 +161,7 @@ DB_SHOW_COMMAND(com, db_show_com)
 		}
 
 	ic = (const struct ieee80211com *) addr;
-	_db_show_com(ic, showvaps, showsta, showmesh, showprocs);
+	_db_show_com(ic, showvaps, showsta, showmesh, showprocs, showscan);
 }
 
 DB_SHOW_ALL_COMMAND(vaps, db_show_all_vaps)
@@ -345,6 +348,61 @@ _db_show_tdma(const char *sep, const struct ieee80211_tdma_state *ts, int showpr
 }
 #endif /* IEEE80211_SUPPORT_TDMA */
 
+static void
+_db_show_scan(const struct ieee80211_scan_state *ss, int showprocs)
+{
+	int i;
+	const struct ieee80211_scanner *ss_ops;
+
+	db_printf("SCAN %p:", ss);
+	db_printf(" vap %p ic %p", ss->ss_vap, ss->ss_ic);
+	db_printf("\n");
+
+	db_printf("\tss_ops %p (%s) ss_priv %p",
+	    ss->ss_ops, ss->ss_ops->scan_name, ss->ss_priv);
+	db_printf("\n");
+	if (showprocs) {
+		ss_ops = ss->ss_ops;
+		DB_PRINTSYM("\t", "scan_attach", ss_ops->scan_attach);
+		DB_PRINTSYM("\t", "scan_detach", ss_ops->scan_detach);
+		DB_PRINTSYM("\t", "scan_start", ss_ops->scan_start);
+		DB_PRINTSYM("\t", "scan_restart", ss_ops->scan_restart);
+		DB_PRINTSYM("\t", "scan_cancel", ss_ops->scan_cancel);
+		DB_PRINTSYM("\t", "scan_end", ss_ops->scan_end);
+		DB_PRINTSYM("\t", "scan_flush", ss_ops->scan_flush);
+		DB_PRINTSYM("\t", "scan_pickchan", ss_ops->scan_pickchan);
+		DB_PRINTSYM("\t", "scan_add", ss_ops->scan_add);
+		DB_PRINTSYM("\t", "scan_age", ss_ops->scan_age);
+		DB_PRINTSYM("\t", "scan_assoc_fail", ss_ops->scan_assoc_fail);
+		DB_PRINTSYM("\t", "scan_assoc_success", ss_ops->scan_assoc_success);
+		DB_PRINTSYM("\t", "scan_iterate", ss_ops->scan_iterate);
+		DB_PRINTSYM("\t", "scan_spare0", ss_ops->scan_spare0);
+		DB_PRINTSYM("\t", "scan_spare1", ss_ops->scan_spare1);
+		DB_PRINTSYM("\t", "scan_spare2", ss_ops->scan_spare2);
+		DB_PRINTSYM("\t", "scan_spare3", ss_ops->scan_spare3);
+	}
+
+	db_printf("\tss_flags %b", ss->ss_flags, IEEE80211_SS_FLAGS_BITS);
+	db_printf("\n");
+
+	db_printf("\tss_nssid %u", ss->ss_nssid);
+	for (i = 0; i < ss->ss_nssid && i < IEEE80211_SCAN_MAX_SSID; i++)
+		_db_show_ssid(" ss_nssid[%d]", i,
+		    ss->ss_ssid[i].len, ss->ss_ssid[i].ssid);
+	db_printf("\n");
+
+	db_printf("\tss_chans:\n");
+	for (i = 0; i < ss->ss_last && i < IEEE80211_SCAN_MAX; i++) {
+		db_printf("\t%-3d", i);
+		_db_show_channel(" ", ss->ss_chans[i]);
+		db_printf("\n");
+	}
+
+	db_printf("\tss_next %u ss_last %u ss_mindwell %lu ss_maxdwell %lu",
+	    ss->ss_next, ss->ss_last, ss->ss_mindwell, ss->ss_maxdwell);
+	db_printf("\n");
+}
+
 static void
 _db_show_vap(const struct ieee80211vap *vap, int showmesh, int showprocs)
 {
@@ -532,7 +590,7 @@ _db_show_vap(const struct ieee80211vap *vap, int showmesh, int showprocs)
 
 static void
 _db_show_com(const struct ieee80211com *ic, int showvaps, int showsta,
-    int showmesh, int showprocs)
+    int showmesh, int showprocs, int showscan)
 {
 	struct ieee80211vap *vap;
 
@@ -679,6 +737,10 @@ _db_show_com(const struct ieee80211com *ic, int showvaps, int showsta,
 		DB_PRINTSYM("\t", "ic_addba_response", ic->ic_addba_response);
 		DB_PRINTSYM("\t", "ic_addba_stop", ic->ic_addba_stop);
 	}
+	if (showscan) {
+		db_printf("\n");
+		_db_show_scan(ic->ic_scan, showprocs);
+	}
 	if (showvaps && !TAILQ_EMPTY(&ic->ic_vaps)) {
 		db_printf("\n");
 		TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next)
@@ -707,7 +769,7 @@ _db_show_all_vaps(void *arg, struct ieee80211com *ic)
 			db_printf(" %s(%p)", if_name(vap->iv_ifp), vap);
 		db_printf("\n");
 	} else
-		_db_show_com(ic, 1, 1, 1, 1);
+		_db_show_com(ic, 1, 1, 1, 1, 1);
 }
 
 static void
diff --git a/sys/net80211/ieee80211_ioctl.c b/sys/net80211/ieee80211_ioctl.c
index 6fe39f588bab..674d163e3e67 100644
--- a/sys/net80211/ieee80211_ioctl.c
+++ b/sys/net80211/ieee80211_ioctl.c
@@ -2590,8 +2590,10 @@ ieee80211_scanreq(struct ieee80211vap *vap, struct ieee80211_scan_req *sr)
 		sr->sr_flags |= IEEE80211_IOC_SCAN_NOPICK;
 
 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
-	    "%s: flags 0x%x%s duration 0x%x mindwell %u maxdwell %u nssid %d\n",
-	    __func__, sr->sr_flags,
+	    "%s: vap %p iv_state %#x (%s) flags 0x%x%s "
+	    "duration 0x%x mindwell %u maxdwell %u nssid %d\n",
+	    __func__, vap, vap->iv_state, ieee80211_state_name[vap->iv_state],
+	    sr->sr_flags,
 	    (vap->iv_ifp->if_flags & IFF_UP) == 0 ? " (!IFF_UP)" : "",
 	    sr->sr_duration, sr->sr_mindwell, sr->sr_maxdwell, sr->sr_nssid);
 	/*
diff --git a/sys/net80211/ieee80211_scan.h b/sys/net80211/ieee80211_scan.h
index 4274f3948db6..a33864b102e2 100644
--- a/sys/net80211/ieee80211_scan.h
+++ b/sys/net80211/ieee80211_scan.h
@@ -147,6 +147,10 @@ struct ieee80211_scan_state {
 	unsigned long	ss_maxdwell;		/* max dwell on channel */
 };
 
+#define	IEEE80211_SS_FLAGS_BITS \
+	"\20\1NOPICK\2ACTIVE\3PICK1ST\4BGSCAN\5ONCE\6NOBCAST\7NOJOIN" \
+	"\15GOTPICK"
+
 /*
  * The upper 16 bits of the flags word is used to communicate
  * information to the scanning code that is NOT recorded in
@@ -328,7 +332,7 @@ struct ieee80211_scanner {
 	void	(*scan_spare0)(void);
 	void	(*scan_spare1)(void);
 	void	(*scan_spare2)(void);
-	void	(*scan_spare4)(void);
+	void	(*scan_spare3)(void);
 };
 void	ieee80211_scanner_register(enum ieee80211_opmode,
 		const struct ieee80211_scanner *);