On each TX descriptor allocation, a free entry is found by traversing the TX
descriptors array.
Improve this by holding a bitmap of all TX descriptors, and using efficient
bit operations to search for free entries.
The bitmap is 32 bits long, assuming that the maximum number of
descriptors (ACX_TX_DESCRIPTORS) will never exceed 32.
Signed-off-by: Ido Yariv <ido@xxxxxxxxxx>
---
drivers/net/wireless/wl12xx/wl1271.h | 1 +
drivers/net/wireless/wl12xx/wl1271_main.c | 1 +
drivers/net/wireless/wl12xx/wl1271_tx.c | 38 ++++++++++++++++------------
3 files changed, 24 insertions(+), 16 deletions(-)
diff --git a/drivers/net/wireless/wl12xx/wl1271.h b/drivers/net/wireless/wl12xx/wl1271.h
index 8a4cd76..650fc00 100644
--- a/drivers/net/wireless/wl12xx/wl1271.h
+++ b/drivers/net/wireless/wl12xx/wl1271.h
@@ -397,6 +397,7 @@ struct wl1271 {
struct work_struct tx_work;
/* Pending TX frames */
+ unsigned long tx_frames_map;
struct sk_buff *tx_frames[ACX_TX_DESCRIPTORS];
int tx_frames_cnt;
diff --git a/drivers/net/wireless/wl12xx/wl1271_main.c b/drivers/net/wireless/wl12xx/wl1271_main.c
index 5643834..59f1aee 100644
--- a/drivers/net/wireless/wl12xx/wl1271_main.c
+++ b/drivers/net/wireless/wl12xx/wl1271_main.c
@@ -2528,6 +2528,7 @@ struct ieee80211_hw *wl1271_alloc_hw(void)
wl->sg_enabled = true;
wl->hw_pg_ver = -1;
+ wl->tx_frames_map = 0;
for (i = 0; i < ACX_TX_DESCRIPTORS; i++)
wl->tx_frames[i] = NULL;
diff --git a/drivers/net/wireless/wl12xx/wl1271_tx.c b/drivers/net/wireless/wl12xx/wl1271_tx.c
index 90a8909..e2ba5a7 100644
--- a/drivers/net/wireless/wl12xx/wl1271_tx.c
+++ b/drivers/net/wireless/wl12xx/wl1271_tx.c
@@ -30,17 +30,26 @@
#include "wl1271_ps.h"
#include "wl1271_tx.h"
-static int wl1271_tx_id(struct wl1271 *wl, struct sk_buff *skb)
+static int wl1271_alloc_tx_id(struct wl1271 *wl, struct sk_buff *skb)
{
- int i;
- for (i = 0; i < ACX_TX_DESCRIPTORS; i++)
- if (wl->tx_frames[i] == NULL) {
- wl->tx_frames[i] = skb;
- wl->tx_frames_cnt++;
- return i;
- }
+ int id;
+
+ id = find_first_zero_bit(&wl->tx_frames_map, ACX_TX_DESCRIPTORS);
+ if (id >= ACX_TX_DESCRIPTORS)
+ return -EBUSY;
+
+ set_bit(id, &wl->tx_frames_map);
+ wl->tx_frames[id] = skb;
+ wl->tx_frames_cnt++;
+ return id;
+}
- return -EBUSY;
+static void wl1271_free_tx_id(struct wl1271 *wl, int id)
+{
+ if (test_and_clear_bit(id, &wl->tx_frames_map)) {
+ wl->tx_frames[id] = NULL;
+ wl->tx_frames_cnt--;
+ }
}
static int wl1271_tx_allocate(struct wl1271 *wl, struct sk_buff *skb, u32 extra,
@@ -55,7 +64,7 @@ static int wl1271_tx_allocate(struct wl1271 *wl, struct sk_buff *skb, u32 extra,
return -EAGAIN;
/* allocate free identifier for the packet */
- id = wl1271_tx_id(wl, skb);
+ id = wl1271_alloc_tx_id(wl, skb);
if (id < 0)
return id;
@@ -79,8 +88,7 @@ static int wl1271_tx_allocate(struct wl1271 *wl, struct sk_buff *skb, u32 extra,
"tx_allocate: size: %d, blocks: %d, id: %d",
total_len, total_blocks, id);
} else {
- wl->tx_frames[id] = NULL;
- wl->tx_frames_cnt--;
+ wl1271_free_tx_id(wl, id);
}
return ret;
@@ -353,8 +361,7 @@ static void wl1271_tx_complete_packet(struct wl1271 *wl,
/* return the packet to the stack */
ieee80211_tx_status(wl->hw, skb);
- wl->tx_frames[result->id] = NULL;
- wl->tx_frames_cnt--;
+ wl1271_free_tx_id(wl, result->id);
}
/* Called upon reception of a TX complete interrupt */
@@ -423,11 +430,10 @@ void wl1271_tx_reset(struct wl1271 *wl)
for (i = 0; i < ACX_TX_DESCRIPTORS; i++)
if (wl->tx_frames[i] != NULL) {
skb = wl->tx_frames[i];
- wl->tx_frames[i] = NULL;
+ wl1271_free_tx_id(wl, i);
wl1271_debug(DEBUG_TX, "freeing skb 0x%p", skb);
ieee80211_tx_status(wl->hw, skb);
}
- wl->tx_frames_cnt = 0;
}
#define WL1271_TX_FLUSH_TIMEOUT 500000
--
1.7.0.4
--
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