firewire: use split transaction timeout only for split transactions
Instead of starting the split transaction timeout timer when any request
is submitted, start it only when the destination's ACK_PENDING has been
received. This prevents us from using a timeout that is too short, and,
if the controller's AT queue is emptying very slowly, from cancelling
a packet that has not yet been sent.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
diff --git a/drivers/firewire/core-transaction.c b/drivers/firewire/core-transaction.c
index 9e81cc5..d00f8ce 100644
--- a/drivers/firewire/core-transaction.c
+++ b/drivers/firewire/core-transaction.c
@@ -72,6 +72,15 @@
#define PHY_CONFIG_ROOT_ID(node_id) ((((node_id) & 0x3f) << 24) | (1 << 23))
#define PHY_IDENTIFIER(id) ((id) << 30)
+/* returns 0 if the split timeout handler is already running */
+static int try_cancel_split_timeout(struct fw_transaction *t)
+{
+ if (t->is_split_transaction)
+ return del_timer(&t->split_timeout_timer);
+ else
+ return 1;
+}
+
static int close_transaction(struct fw_transaction *transaction,
struct fw_card *card, int rcode)
{
@@ -81,7 +90,7 @@
spin_lock_irqsave(&card->lock, flags);
list_for_each_entry(t, &card->transaction_list, link) {
if (t == transaction) {
- if (!del_timer(&t->split_timeout_timer)) {
+ if (!try_cancel_split_timeout(t)) {
spin_unlock_irqrestore(&card->lock, flags);
goto timed_out;
}
@@ -141,16 +150,28 @@
card->tlabel_mask &= ~(1ULL << t->tlabel);
spin_unlock_irqrestore(&card->lock, flags);
- card->driver->cancel_packet(card, &t->packet);
-
- /*
- * At this point cancel_packet will never call the transaction
- * callback, since we just took the transaction out of the list.
- * So do it here.
- */
t->callback(card, RCODE_CANCELLED, NULL, 0, t->callback_data);
}
+static void start_split_transaction_timeout(struct fw_transaction *t,
+ struct fw_card *card)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&card->lock, flags);
+
+ if (list_empty(&t->link) || WARN_ON(t->is_split_transaction)) {
+ spin_unlock_irqrestore(&card->lock, flags);
+ return;
+ }
+
+ t->is_split_transaction = true;
+ mod_timer(&t->split_timeout_timer,
+ jiffies + card->split_timeout_jiffies);
+
+ spin_unlock_irqrestore(&card->lock, flags);
+}
+
static void transmit_complete_callback(struct fw_packet *packet,
struct fw_card *card, int status)
{
@@ -162,7 +183,7 @@
close_transaction(t, card, RCODE_COMPLETE);
break;
case ACK_PENDING:
- t->timestamp = packet->timestamp;
+ start_split_transaction_timeout(t, card);
break;
case ACK_BUSY_X:
case ACK_BUSY_A:
@@ -349,11 +370,9 @@
t->node_id = destination_id;
t->tlabel = tlabel;
t->card = card;
+ t->is_split_transaction = false;
setup_timer(&t->split_timeout_timer,
split_transaction_timeout_callback, (unsigned long)t);
- /* FIXME: start this timer later, relative to t->timestamp */
- mod_timer(&t->split_timeout_timer,
- jiffies + card->split_timeout_jiffies);
t->callback = callback;
t->callback_data = callback_data;
@@ -926,7 +945,7 @@
spin_lock_irqsave(&card->lock, flags);
list_for_each_entry(t, &card->transaction_list, link) {
if (t->node_id == source && t->tlabel == tlabel) {
- if (!del_timer(&t->split_timeout_timer)) {
+ if (!try_cancel_split_timeout(t)) {
spin_unlock_irqrestore(&card->lock, flags);
goto timed_out;
}