wl1271: Allocate TX descriptors more efficiently

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.

Signed-off-by: Ido Yariv <ido@wizery.com>
Reviewed-by: Juuso Oikarinen <juuso.oikarinen@nokia.com>
Signed-off-by: Luciano Coelho <luciano.coelho@nokia.com>
This commit is contained in:
Ido Yariv 2010-10-12 16:20:06 +02:00 committed by John W. Linville
parent a522550a28
commit 25eeb9e387
3 changed files with 24 additions and 16 deletions

View File

@ -398,6 +398,7 @@ struct wl1271 {
struct work_struct tx_work;
/* Pending TX frames */
unsigned long tx_frames_map[BITS_TO_LONGS(ACX_TX_DESCRIPTORS)];
struct sk_buff *tx_frames[ACX_TX_DESCRIPTORS];
int tx_frames_cnt;

View File

@ -2532,6 +2532,7 @@ struct ieee80211_hw *wl1271_alloc_hw(void)
wl->sg_enabled = true;
wl->hw_pg_ver = -1;
memset(wl->tx_frames_map, 0, sizeof(wl->tx_frames_map));
for (i = 0; i < ACX_TX_DESCRIPTORS; i++)
wl->tx_frames[i] = NULL;

View File

@ -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;
return -EBUSY;
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;
}
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;
@ -352,8 +360,7 @@ 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 */
@ -422,11 +429,10 @@ 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