linux-kernel - [PATCH] staging: rtl8723bs: simplify control flow

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Date:   Sun, 3 Apr 2022 18:42:07 -0400
From:   Sevinj Aghayeva <sevinj.aghayeva@...il.com>
To:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        linux-staging@...ts.linux.dev, linux-kernel@...r.kernel.org,
        outreachy@...ts.linux.dev
Subject: [PATCH] staging: rtl8723bs: simplify control flow

Checkpatch issues "WARNING: else is not generally useful after a break
or return" for the following code:

while (1) {
	do_join_r = rtw_do_join(padapter);
	if (do_join_r == _SUCCESS) {
		break;
	} else {
		rtw_dec_to_roam(padapter);

		if (rtw_to_roam(padapter) > 0) {
			continue;
		} else {
			rtw_indicate_disconnect(padapter);
			break;
		}
	}
}

We simplify this code in multiple steps. First, we remove do_join_r
variable because it is only used right after it is assigned. Second,
we remove the unnecessary else statement right after break:

while (1) {
	if (rtw_do_join(padapter) == _SUCCESS)
		break;
	rtw_dec_to_roam(padapter);

	if (rtw_to_roam(padapter) > 0) {
		continue;
	} else {
		rtw_indicate_disconnect(padapter);
		break;
	}
}

Next, we move the call to rtw_do_join into the while test because the
while will loop only until the call is successful:

while (rtw_do_join(padapter) != _SUCCESS) {
	rtw_dec_to_roam(padapter);
	if (rtw_to_roam(padapter) > 0) {
		continue;
	} else {
		rtw_indicate_disconnect(padapter);
		break;
	}
}

Finally, looking at the code above, it is clear that the code will
break out of the loop if rtw_to_roam call is <= 0. Hence:

while (rtw_do_join(padapter) != _SUCCESS) {
	rtw_dec_to_roam(padapter);
	if (rtw_to_roam(padapter) <= 0) {
		rtw_indicate_disconnect(padapter);
		break;
	}
}

Signed-off-by: Sevinj Aghayeva <sevinj.aghayeva@...il.com>
---
 drivers/staging/rtl8723bs/core/rtw_mlme.c | 18 ++++--------------
 1 file changed, 4 insertions(+), 14 deletions(-)

diff --git a/drivers/staging/rtl8723bs/core/rtw_mlme.c b/drivers/staging/rtl8723bs/core/rtw_mlme.c
index 3eacf8f9d236..a45df775d535 100644
--- a/drivers/staging/rtl8723bs/core/rtw_mlme.c
+++ b/drivers/staging/rtl8723bs/core/rtw_mlme.c
@@ -2594,30 +2594,20 @@ void _rtw_roaming(struct adapter *padapter, struct wlan_network *tgt_network)
 {
 	struct mlme_priv *pmlmepriv = &padapter->mlmepriv;
 	struct wlan_network *cur_network = &pmlmepriv->cur_network;
-	int do_join_r;
 
 	if (rtw_to_roam(padapter) > 0) {
 		memcpy(&pmlmepriv->assoc_ssid, &cur_network->network.ssid, sizeof(struct ndis_802_11_ssid));
 
 		pmlmepriv->assoc_by_bssid = false;
 
-		while (1) {
-			do_join_r = rtw_do_join(padapter);
-			if (do_join_r == _SUCCESS) {
+		while (rtw_do_join(padapter) != _SUCCESS) {
+			rtw_dec_to_roam(padapter);
+			if (rtw_to_roam(padapter) <= 0) {
+				rtw_indicate_disconnect(padapter);
 				break;
-			} else {
-				rtw_dec_to_roam(padapter);
-
-				if (rtw_to_roam(padapter) > 0) {
-					continue;
-				} else {
-					rtw_indicate_disconnect(padapter);
-					break;
-				}
 			}
 		}
 	}
-
 }
 
 signed int rtw_linked_check(struct adapter *padapter)
-- 
2.25.1