Commit 0c126ec3 authored by Alex Elder's avatar Alex Elder Committed by David S. Miller
Browse files

net: ipa: always use transaction IDs instead of lists 



In gsi_channel_trans_complete(), use the completed and pending IDs
to determine whether there are any transactions in completed state.

Similarly, in gsi_channel_trans_cancel_pending(), use the pending
and committed IDs to mark pending transactions cancelled.  Rearrange
the logic a bit there for a simpler result.

This removes the only user of list_last_entry_or_null(), so get rid
of that macro.

Remove the temporary warnings added by the previous commit.

Signed-off-by: default avatarAlex Elder <elder@linaro.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 6fff9261

drivers/net/ipa/gsi_private.h

+0 −14
Original line number Diff line number Diff line
@@ -16,20 +16,6 @@ struct gsi_channel; 


#define GSI_RING_ELEMENT_SIZE	16	/* bytes; must be a power of 2 */



/**

 * list_last_entry_or_null - get the last element from a list

 * @ptr:	the list head to take the element from.

 * @type:	the type of the struct this is embedded in.

 * @member:	the name of the list_head within the struct.

 *

 * Note that if the list is empty, it returns NULL.

 */

#define list_last_entry_or_null(ptr, type, member) ({ \

	struct list_head *head__ = (ptr); \

	struct list_head *pos__ = READ_ONCE(head__->prev); \

	pos__ != head__ ? list_entry(pos__, type, member) : NULL; \

})



/**

 * gsi_trans_move_complete() - Mark a GSI transaction completed

 * @trans:	Transaction to commit

drivers/net/ipa/gsi_trans.c

+16 −42
Original line number Diff line number Diff line
@@ -239,22 +239,11 @@ struct gsi_trans *gsi_channel_trans_complete(struct gsi_channel *channel) 
{

	struct gsi_trans_info *trans_info = &channel->trans_info;

	u16 trans_id = trans_info->completed_id;

	struct gsi_trans *trans;



	trans = list_first_entry_or_null(&trans_info->complete,

					 struct gsi_trans, links);



	if (!trans) {

		WARN_ON(trans_id != trans_info->pending_id);

	if (trans_id == trans_info->pending_id)

		return NULL;

	}



	if (!WARN_ON(trans_id == trans_info->pending_id)) {

		trans_id %= channel->tre_count;

		WARN_ON(trans != &trans_info->trans[trans_id]);

	}



	return trans;

	return &trans_info->trans[trans_id %= channel->tre_count];

}



/* Move a transaction from the allocated list to the committed list */
@@ -705,47 +694,32 @@ void gsi_trans_complete(struct gsi_trans *trans) 
void gsi_channel_trans_cancel_pending(struct gsi_channel *channel)

{

	struct gsi_trans_info *trans_info = &channel->trans_info;

	struct gsi_trans *trans;

	struct gsi_trans *first;

	struct gsi_trans *last;

	bool cancelled;

	u16 trans_id = trans_info->pending_id;



	/* channel->gsi->mutex is held by caller */

	spin_lock_bh(&trans_info->spinlock);



	cancelled = !list_empty(&trans_info->pending);

	list_for_each_entry(trans, &trans_info->pending, links)

		trans->cancelled = true;



	list_splice_tail_init(&trans_info->pending, &trans_info->complete);



	first = list_first_entry_or_null(&trans_info->complete,

					 struct gsi_trans, links);

	last = list_last_entry_or_null(&trans_info->complete,

				       struct gsi_trans, links);



	spin_unlock_bh(&trans_info->spinlock);



	/* All pending transactions are now completed */

	WARN_ON(cancelled != (trans_info->pending_id !=

				trans_info->committed_id));

	/* If there are no pending transactions, we're done */

	if (trans_id == trans_info->committed_id)

		return;



	/* Mark all pending transactions cancelled */

	do {

		struct gsi_trans *trans;



		trans = &trans_info->trans[trans_id % channel->tre_count];

		trans->cancelled = true;

	} while (++trans_id != trans_info->committed_id);



	/* All pending transactions are now completed */

	trans_info->pending_id = trans_info->committed_id;



	/* Schedule NAPI polling to complete the cancelled transactions */

	if (cancelled) {

		u16 trans_id;



	napi_schedule(&channel->napi);



		trans_id = trans_info->completed_id;

		trans = &trans_info->trans[trans_id % channel->tre_count];

		WARN_ON(trans != first);



		trans_id = trans_info->pending_id - 1;

		trans = &trans_info->trans[trans_id % channel->tre_count];

		WARN_ON(trans != last);

	}

}



/* Issue a command to read a single byte from a channel */