@@ -82,9 +82,10 @@ struct gsi_trans_pool {
struct gsi_trans_info {
atomic_t tre_avail; /* TREs available for allocation */
struct gsi_trans_pool pool; /* transaction pool */
+ struct gsi_trans **map; /* TRE -> transaction map */
+
struct gsi_trans_pool sg_pool; /* scatterlist pool */
struct gsi_trans_pool cmd_pool; /* command payload DMA pool */
- struct gsi_trans **map; /* TRE -> transaction map */
spinlock_t spinlock; /* protects updates to the lists */
struct list_head alloc; /* allocated, not committed */
@@ -709,6 +709,7 @@ void gsi_trans_read_byte_done(struct gsi *gsi, u32 channel_id)
int gsi_channel_trans_init(struct gsi *gsi, u32 channel_id)
{
struct gsi_channel *channel = &gsi->channel[channel_id];
+ u32 tre_count = channel->tre_count;
struct gsi_trans_info *trans_info;
u32 tre_max;
int ret;
@@ -716,30 +717,40 @@ int gsi_channel_trans_init(struct gsi *gsi, u32 channel_id)
/* Ensure the size of a channel element is what's expected */
BUILD_BUG_ON(sizeof(struct gsi_tre) != GSI_RING_ELEMENT_SIZE);
- /* The map array is used to determine what transaction is associated
- * with a TRE that the hardware reports has completed. We need one
- * map entry per TRE.
- */
trans_info = &channel->trans_info;
- trans_info->map = kcalloc(channel->tre_count, sizeof(*trans_info->map),
- GFP_KERNEL);
- if (!trans_info->map)
- return -ENOMEM;
- /* We can't use more TREs than there are available in the ring.
+ /* The tre_avail field is what ultimately limits the number of
+ * outstanding transactions and their resources. A transaction
+ * allocation succeeds only if the TREs available are sufficient
+ * for what the transaction might need.
+ */
+ tre_max = gsi_channel_tre_max(channel->gsi, channel_id);
+ atomic_set(&trans_info->tre_avail, tre_max);
+
+ /* We can't use more TREs than the number available in the ring.
* This limits the number of transactions that can be outstanding.
* Worst case is one TRE per transaction (but we actually limit
- * it to something a little less than that). We allocate resources
- * for transactions (including transaction structures) based on
- * this maximum number.
+ * it to something a little less than that). By allocating a
+ * power-of-two number of transactions we can use an index
+ * modulo that number to determine the next one that's free.
+ * Transactions are allocated one at a time.
*/
- tre_max = gsi_channel_tre_max(channel->gsi, channel_id);
-
- /* Transactions are allocated one at a time. */
ret = gsi_trans_pool_init(&trans_info->pool, sizeof(struct gsi_trans),
tre_max, 1);
if (ret)
- goto err_kfree;
+ return -ENOMEM;
+
+ /* A completion event contains a pointer to the TRE that caused
+ * the event (which will be the last one used by the transaction).
+ * Each entry in this map records the transaction associated
+ * with a corresponding completed TRE.
+ */
+ trans_info->map = kcalloc(tre_count, sizeof(*trans_info->map),
+ GFP_KERNEL);
+ if (!trans_info->map) {
+ ret = -ENOMEM;
+ goto err_trans_free;
+ }
/* A transaction uses a scatterlist array to represent the data
* transfers implemented by the transaction. Each scatterlist
@@ -751,16 +762,7 @@ int gsi_channel_trans_init(struct gsi *gsi, u32 channel_id)
sizeof(struct scatterlist),
tre_max, channel->trans_tre_max);
if (ret)
- goto err_trans_pool_exit;
-
- /* Finally, the tre_avail field is what ultimately limits the number
- * of outstanding transactions and their resources. A transaction
- * allocation succeeds only if the TREs available are sufficient for
- * what the transaction might need. Transaction resource pools are
- * sized based on the maximum number of outstanding TREs, so there
- * will always be resources available if there are TREs available.
- */
- atomic_set(&trans_info->tre_avail, tre_max);
+ goto err_map_free;
spin_lock_init(&trans_info->spinlock);
INIT_LIST_HEAD(&trans_info->alloc);
@@ -771,10 +773,10 @@ int gsi_channel_trans_init(struct gsi *gsi, u32 channel_id)
return 0;
-err_trans_pool_exit:
- gsi_trans_pool_exit(&trans_info->pool);
-err_kfree:
+err_map_free:
kfree(trans_info->map);
+err_trans_free:
+ gsi_trans_pool_exit(&trans_info->pool);
dev_err(gsi->dev, "error %d initializing channel %u transactions\n",
ret, channel_id);
The transaction map is really associated with the transaction pool; move its definition earlier in the gsi_trans_info structure. Rearrange initialization in gsi_channel_trans_init() so it sets the tre_avail value first, then initializes the transaction pool, and finally allocating the transaction map. Update comments. Signed-off-by: Alex Elder <elder@linaro.org> --- v2: Fixed the misspelling of "outstanding" in two spots. drivers/net/ipa/gsi.h | 3 +- drivers/net/ipa/gsi_trans.c | 60 +++++++++++++++++++------------------ 2 files changed, 33 insertions(+), 30 deletions(-)