brcmfmac: reduce firmware-signalling locking scope in rx path

In the receive path a spinlock is taken upon parsing the TLV signal
header. This moves to locking to the TLV handling functions where
it protects the data structures.

Reviewed-by: Hante Meuleman <meuleman@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 51 insertions, 26 deletions

diff --git a/drivers/net/wireless/brcm80211/brcmfmac/fwsignal.c b/drivers/net/wireless/brcm80211/brcmfmac/fwsignal.c
index e92a3ce58c02..f0d9f7f6c83d 100644
--- a/drivers/net/wireless/brcm80211/brcmfmac/fwsignal.c
+++ b/drivers/net/wireless/brcm80211/brcmfmac/fwsignal.c
@@ -905,10 +905,26 @@ static int brcmf_fws_rssi_indicate(struct brcmf_fws_info *fws, s8 rssi)
         return 0;
 }
 
+/* using macro so sparse checking does not complain
+ * about locking imbalance.
+ */
+#define brcmf_fws_lock(drvr, flags)                             \
+do {                                                            \
+        flags = 0;                                              \
+        spin_lock_irqsave(&((drvr)->fws_spinlock), (flags));    \
+} while (0)
+
+/* using macro so sparse checking does not complain
+ * about locking imbalance.
+ */
+#define brcmf_fws_unlock(drvr, flags) \
+        spin_unlock_irqrestore(&((drvr)->fws_spinlock), (flags))
+
 static
 int brcmf_fws_macdesc_indicate(struct brcmf_fws_info *fws, u8 type, u8 *data)
 {
         struct brcmf_fws_mac_descriptor *entry, *existing;
+        ulong flags;
         u8 mac_handle;
         u8 ifidx;
         u8 *addr;
@@ -922,8 +938,10 @@ int brcmf_fws_macdesc_indicate(struct brcmf_fws_info *fws, u8 type, u8 *data)
                 if (entry->occupied) {
                         brcmf_dbg(TRACE, "deleting %s mac %pM\n",
                                   entry->name, addr);
+                        brcmf_fws_lock(fws->drvr, flags);
                         brcmf_fws_macdesc_cleanup(fws, entry, -1);
                         brcmf_fws_macdesc_deinit(entry);
+                        brcmf_fws_unlock(fws->drvr, flags);
                 } else
                         fws->stats.mac_update_failed++;
                 return 0;
@@ -932,11 +950,13 @@ int brcmf_fws_macdesc_indicate(struct brcmf_fws_info *fws, u8 type, u8 *data)
         existing = brcmf_fws_macdesc_lookup(fws, addr);
         if (IS_ERR(existing)) {
                 if (!entry->occupied) {
+                        brcmf_fws_lock(fws->drvr, flags);
                         entry->mac_handle = mac_handle;
                         brcmf_fws_macdesc_init(entry, addr, ifidx);
                         brcmf_fws_macdesc_set_name(fws, entry);
                         brcmu_pktq_init(&entry->psq, BRCMF_FWS_PSQ_PREC_COUNT,
                                         BRCMF_FWS_PSQ_LEN);
+                        brcmf_fws_unlock(fws->drvr, flags);
                         brcmf_dbg(TRACE, "add %s mac %pM\n", entry->name, addr);
                 } else {
                         fws->stats.mac_update_failed++;
@@ -944,11 +964,13 @@ int brcmf_fws_macdesc_indicate(struct brcmf_fws_info *fws, u8 type, u8 *data)
         } else {
                 if (entry != existing) {
                         brcmf_dbg(TRACE, "copy mac %s\n", existing->name);
+                        brcmf_fws_lock(fws->drvr, flags);
                         memcpy(entry, existing,
                                offsetof(struct brcmf_fws_mac_descriptor, psq));
                         entry->mac_handle = mac_handle;
                         brcmf_fws_macdesc_deinit(existing);
                         brcmf_fws_macdesc_set_name(fws, entry);
+                        brcmf_fws_unlock(fws->drvr, flags);
                         brcmf_dbg(TRACE, "relocate %s mac %pM\n", entry->name,
                                   addr);
                 } else {
@@ -964,7 +986,9 @@ static int brcmf_fws_macdesc_state_indicate(struct brcmf_fws_info *fws,
                                             u8 type, u8 *data)
 {
         struct brcmf_fws_mac_descriptor *entry;
+        ulong flags;
         u8 mac_handle;
+        int ret;
 
         mac_handle = data[0];
         entry = &fws->desc.nodes[mac_handle & 0x1F];
@@ -972,26 +996,30 @@ static int brcmf_fws_macdesc_state_indicate(struct brcmf_fws_info *fws,
                 fws->stats.mac_ps_update_failed++;
                 return -ESRCH;
         }
+        brcmf_fws_lock(fws->drvr, flags);
         /* a state update should wipe old credits */
         entry->requested_credit = 0;
         entry->requested_packet = 0;
         if (type == BRCMF_FWS_TYPE_MAC_OPEN) {
                 entry->state = BRCMF_FWS_STATE_OPEN;
-                return BRCMF_FWS_RET_OK_SCHEDULE;
+                ret = BRCMF_FWS_RET_OK_SCHEDULE;
         } else {
                 entry->state = BRCMF_FWS_STATE_CLOSE;
                 brcmf_fws_tim_update(fws, entry, BRCMF_FWS_FIFO_AC_BK, false);
                 brcmf_fws_tim_update(fws, entry, BRCMF_FWS_FIFO_AC_BE, false);
                 brcmf_fws_tim_update(fws, entry, BRCMF_FWS_FIFO_AC_VI, false);
                 brcmf_fws_tim_update(fws, entry, BRCMF_FWS_FIFO_AC_VO, true);
+                ret = BRCMF_FWS_RET_OK_NOSCHEDULE;
         }
-        return BRCMF_FWS_RET_OK_NOSCHEDULE;
+        brcmf_fws_unlock(fws->drvr, flags);
+        return ret;
 }
 
 static int brcmf_fws_interface_state_indicate(struct brcmf_fws_info *fws,
                                               u8 type, u8 *data)
 {
         struct brcmf_fws_mac_descriptor *entry;
+        ulong flags;
         u8 ifidx;
         int ret;
 
@@ -1010,17 +1038,24 @@ static int brcmf_fws_interface_state_indicate(struct brcmf_fws_info *fws,
 
         brcmf_dbg(TRACE, "%s (%d): %s\n", brcmf_fws_get_tlv_name(type), type,
                   entry->name);
+        brcmf_fws_lock(fws->drvr, flags);
         switch (type) {
         case BRCMF_FWS_TYPE_INTERFACE_OPEN:
                 entry->state = BRCMF_FWS_STATE_OPEN;
-                return BRCMF_FWS_RET_OK_SCHEDULE;
+                ret = BRCMF_FWS_RET_OK_SCHEDULE;
+                break;
         case BRCMF_FWS_TYPE_INTERFACE_CLOSE:
                 entry->state = BRCMF_FWS_STATE_CLOSE;
-                return BRCMF_FWS_RET_OK_NOSCHEDULE;
+                ret = BRCMF_FWS_RET_OK_NOSCHEDULE;
+                break;
         default:
                 ret = -EINVAL;
-                break;
+                brcmf_fws_unlock(fws->drvr, flags);
+                goto fail;
         }
+        brcmf_fws_unlock(fws->drvr, flags);
+        return ret;
+
 fail:
         fws->stats.if_update_failed++;
         return ret;
@@ -1030,6 +1065,7 @@ static int brcmf_fws_request_indicate(struct brcmf_fws_info *fws, u8 type,
                                       u8 *data)
 {
         struct brcmf_fws_mac_descriptor *entry;
+        ulong flags;
 
         entry = &fws->desc.nodes[data[1] & 0x1F];
         if (!entry->occupied) {
@@ -1043,12 +1079,14 @@ static int brcmf_fws_request_indicate(struct brcmf_fws_info *fws, u8 type,
         brcmf_dbg(TRACE, "%s (%d): %s cnt %d bmp %d\n",
                   brcmf_fws_get_tlv_name(type), type, entry->name,
                   data[0], data[2]);
+        brcmf_fws_lock(fws->drvr, flags);
         if (type == BRCMF_FWS_TYPE_MAC_REQUEST_CREDIT)
                 entry->requested_credit = data[0];
         else
                 entry->requested_packet = data[0];
 
         entry->ac_bitmap = data[2];
+        brcmf_fws_unlock(fws->drvr, flags);
         return BRCMF_FWS_RET_OK_SCHEDULE;
 }
 
@@ -1345,6 +1383,7 @@ brcmf_fws_txs_process(struct brcmf_fws_info *fws, u8 flags, u32 hslot,
 static int brcmf_fws_fifocreditback_indicate(struct brcmf_fws_info *fws,
                                              u8 *data)
 {
+        ulong flags;
         int i;
 
         if (fws->fcmode != BRCMF_FWS_FCMODE_EXPLICIT_CREDIT) {
@@ -1353,16 +1392,19 @@ static int brcmf_fws_fifocreditback_indicate(struct brcmf_fws_info *fws,
         }
 
         brcmf_dbg(DATA, "enter: data %pM\n", data);
+        brcmf_fws_lock(fws->drvr, flags);
         for (i = 0; i < BRCMF_FWS_FIFO_COUNT; i++)
                 brcmf_fws_return_credits(fws, i, data[i]);
 
         brcmf_dbg(DATA, "map: credit %x delay %x\n", fws->fifo_credit_map,
                   fws->fifo_delay_map);
+        brcmf_fws_unlock(fws->drvr, flags);
         return BRCMF_FWS_RET_OK_SCHEDULE;
 }
 
 static int brcmf_fws_txstatus_indicate(struct brcmf_fws_info *fws, u8 *data)
 {
+        ulong lflags;
         __le32 status_le;
         u32 status;
         u32 hslot;
@@ -1376,7 +1418,10 @@ static int brcmf_fws_txstatus_indicate(struct brcmf_fws_info *fws, u8 *data)
         hslot = brcmf_txstatus_get_field(status, HSLOT);
         genbit = brcmf_txstatus_get_field(status, GENERATION);
 
-        return brcmf_fws_txs_process(fws, flags, hslot, genbit);
+        brcmf_fws_lock(fws->drvr, lflags);
+        brcmf_fws_txs_process(fws, flags, hslot, genbit);
+        brcmf_fws_unlock(fws->drvr, lflags);
+        return BRCMF_FWS_RET_OK_NOSCHEDULE;
 }
 
 static int brcmf_fws_dbg_seqnum_check(struct brcmf_fws_info *fws, u8 *data)
@@ -1389,21 +1434,6 @@ static int brcmf_fws_dbg_seqnum_check(struct brcmf_fws_info *fws, u8 *data)
         return 0;
 }
 
-/* using macro so sparse checking does not complain
- * about locking imbalance.
- */
-#define brcmf_fws_lock(drvr, flags)                             \
-do {                                                            \
-        flags = 0;                                              \
-        spin_lock_irqsave(&((drvr)->fws_spinlock), (flags));    \
-} while (0)
-
-/* using macro so sparse checking does not complain
- * about locking imbalance.
- */
-#define brcmf_fws_unlock(drvr, flags) \
-        spin_unlock_irqrestore(&((drvr)->fws_spinlock), (flags))
-
 static int brcmf_fws_notify_credit_map(struct brcmf_if *ifp,
                                        const struct brcmf_event_msg *e,
                                        void *data)
@@ -1454,7 +1484,6 @@ int brcmf_fws_hdrpull(struct brcmf_pub *drvr, int ifidx, s16 signal_len,
                       struct sk_buff *skb)
 {
         struct brcmf_fws_info *fws = drvr->fws;
-        ulong flags;
         u8 *signal_data;
         s16 data_len;
         u8 type;
@@ -1474,9 +1503,6 @@ int brcmf_fws_hdrpull(struct brcmf_pub *drvr, int ifidx, s16 signal_len,
                 return 0;
         }
 
-        /* lock during tlv parsing */
-        brcmf_fws_lock(drvr, flags);
-
         fws->stats.header_pulls++;
         data_len = signal_len;
         signal_data = skb->data;
@@ -1570,7 +1596,6 @@ int brcmf_fws_hdrpull(struct brcmf_pub *drvr, int ifidx, s16 signal_len,
         if (skb->len == 0)
                 fws->stats.header_only_pkt++;
 
-        brcmf_fws_unlock(drvr, flags);
         return 0;
 }