From 848a049b717c78f849c301e6b838f567cd8dbdfc Mon Sep 17 00:00:00 2001
From: Luiz Otavio O Souza <loos@FreeBSD.org>
Date: Fri, 30 Sep 2016 17:30:39 +0000
Subject: [PATCH] Remove the GLOBAL queue lock which just adds unnecessary
complexity to code (when used together with the individual tx and rx locks).
Sponsored by: Rubicon Communications, LLC (Netgate)
---
sys/arm/ti/cpsw/if_cpsw.c | 33 ++++++++-------------------------
1 file changed, 8 insertions(+), 25 deletions(-)
diff --git a/sys/arm/ti/cpsw/if_cpsw.c b/sys/arm/ti/cpsw/if_cpsw.c
index 89dd935c9316..e3da058703ff 100644
--- a/sys/arm/ti/cpsw/if_cpsw.c
+++ b/sys/arm/ti/cpsw/if_cpsw.c
@@ -301,25 +301,6 @@ cpsw_debugf(const char *fmt, ...)
#define CPSW_RX_UNLOCK(sc) mtx_unlock(&(sc)->rx.lock)
#define CPSW_RX_LOCK_ASSERT(sc) mtx_assert(&(sc)->rx.lock, MA_OWNED)
-#define CPSW_GLOBAL_LOCK(sc) do { \
- if ((mtx_owned(&(sc)->tx.lock) ? 1 : 0) != \
- (mtx_owned(&(sc)->rx.lock) ? 1 : 0)) { \
- panic("cpsw deadlock possibility detection!"); \
- } \
- mtx_lock(&(sc)->tx.lock); \
- mtx_lock(&(sc)->rx.lock); \
-} while (0)
-
-#define CPSW_GLOBAL_UNLOCK(sc) do { \
- CPSW_RX_UNLOCK(sc); \
- CPSW_TX_UNLOCK(sc); \
-} while (0)
-
-#define CPSW_GLOBAL_LOCK_ASSERT(sc) do { \
- CPSW_TX_LOCK_ASSERT(sc); \
- CPSW_RX_LOCK_ASSERT(sc); \
-} while (0)
-
#define CPSW_PORT_LOCK(_sc) do { \
mtx_assert(&(_sc)->lock, MA_NOTOWNED); \
mtx_lock(&(_sc)->lock); \
@@ -1179,7 +1160,7 @@ cpsw_rx_teardown_locked(struct cpsw_softc *sc)
cpsw_write_4(sc, CPSW_CPDMA_RX_TEARDOWN, 0);
for (;;) {
received = cpsw_rx_dequeue(sc);
- CPSW_GLOBAL_UNLOCK(sc);
+ CPSW_RX_UNLOCK(sc);
while (received != NULL) {
next = received->m_nextpkt;
received->m_nextpkt = NULL;
@@ -1188,7 +1169,7 @@ cpsw_rx_teardown_locked(struct cpsw_softc *sc)
if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
received = next;
}
- CPSW_GLOBAL_LOCK(sc);
+ CPSW_RX_LOCK(sc);
if (!sc->rx.running) {
CPSW_DEBUGF(sc,
("finished RX teardown (%d retries)", i));
@@ -1245,10 +1226,12 @@ cpswp_stop_locked(struct cpswp_softc *sc)
/* Tear down the RX/TX queues. */
if (cpsw_ports_down(sc->swsc)) {
- CPSW_GLOBAL_LOCK(sc->swsc);
+ CPSW_RX_LOCK(sc->swsc);
cpsw_rx_teardown_locked(sc->swsc);
+ CPSW_RX_UNLOCK(sc->swsc);
+ CPSW_TX_LOCK(sc->swsc);
cpsw_tx_teardown_locked(sc->swsc);
- CPSW_GLOBAL_UNLOCK(sc->swsc);
+ CPSW_TX_UNLOCK(sc->swsc);
}
/* Stop MAC RX/TX modules. */
@@ -2155,7 +2138,7 @@ cpsw_tx_watchdog(void *msc)
struct cpsw_softc *sc;
sc = msc;
- CPSW_GLOBAL_LOCK(sc);
+ CPSW_TX_LOCK(sc);
if (sc->tx.active_queue_len == 0 || !sc->tx.running) {
sc->watchdog.timer = 0; /* Nothing to do. */
} else if (sc->tx.queue_removes > sc->tx.queue_removes_at_last_tick) {
@@ -2172,7 +2155,7 @@ cpsw_tx_watchdog(void *msc)
}
}
sc->tx.queue_removes_at_last_tick = sc->tx.queue_removes;
- CPSW_GLOBAL_UNLOCK(sc);
+ CPSW_TX_UNLOCK(sc);
/* Schedule another timeout one second from now */
callout_reset(&sc->watchdog.callout, hz, cpsw_tx_watchdog, sc);