[PATCH v6 11/24] bus/fslmc: replace rte_atomic16 with stdatomic

[Stephen Hemminger]

The rte_atomicNN functions and types are deprecated.
The in_use and ref_count flags can be converted to stdatomic.

Note that rte_atomic16_init() and rte_atomic16_clear() were plain
stores with no ordering; only test_and_set() and dec() implied a
full barrier. Initialization happens before the device is put on the
list, so a relaxed store is used there. It is spelled out explicitly
because a plain assignment to an RTE_ATOMIC() object is a sequentially
consistent store when built with enable_stdatomic=true.

Claiming a device now pairs an acquire compare exchange with a release
store on the free path, which is what the test_and_set()/dec() pair was
providing.

Also drop the unneeded NULL check in the loop body: TAILQ_FOREACH
terminates when the iterator becomes NULL, so var is guaranteed
non-NULL inside the loop.

Signed-off-by: Stephen Hemminger <stephen at networkplumber.org>
---
 drivers/bus/fslmc/portal/dpaa2_hw_dpbp.c  | 11 ++++++++---
 drivers/bus/fslmc/portal/dpaa2_hw_dpci.c  | 11 ++++++++---
 drivers/bus/fslmc/portal/dpaa2_hw_dpcon.c | 11 ++++++++---
 drivers/bus/fslmc/portal/dpaa2_hw_dpio.c  | 14 ++++++++++----
 drivers/bus/fslmc/portal/dpaa2_hw_pvt.h   |  9 +++++----
 5 files changed, 39 insertions(+), 17 deletions(-)

diff --git a/drivers/bus/fslmc/portal/dpaa2_hw_dpbp.c b/drivers/bus/fslmc/portal/dpaa2_hw_dpbp.c
index 925e83e97d..d2ddb76baf 100644
--- a/drivers/bus/fslmc/portal/dpaa2_hw_dpbp.c
+++ b/drivers/bus/fslmc/portal/dpaa2_hw_dpbp.c
@@ -84,7 +84,7 @@ dpaa2_create_dpbp_device(int vdev_fd __rte_unused,
 	}
 
 	dpbp_node->dpbp_id = dpbp_id;
-	rte_atomic16_init(&dpbp_node->in_use);
+	rte_atomic_store_explicit(&dpbp_node->in_use, 0, rte_memory_order_relaxed);
 
 	TAILQ_INSERT_TAIL(&dpbp_dev_list, dpbp_node, next);
 
@@ -103,7 +103,11 @@ struct dpaa2_dpbp_dev *dpaa2_alloc_dpbp_dev(void)
 
 	/* Get DPBP dev handle from list using index */
 	TAILQ_FOREACH(dpbp_dev, &dpbp_dev_list, next) {
-		if (dpbp_dev && rte_atomic16_test_and_set(&dpbp_dev->in_use))
+		uint16_t expected = 0;
+
+		if (rte_atomic_compare_exchange_strong_explicit(&dpbp_dev->in_use,
+				&expected, 1, rte_memory_order_acquire,
+				rte_memory_order_relaxed))
 			break;
 	}
 
@@ -118,7 +122,8 @@ void dpaa2_free_dpbp_dev(struct dpaa2_dpbp_dev *dpbp)
 	/* Match DPBP handle and mark it free */
 	TAILQ_FOREACH(dpbp_dev, &dpbp_dev_list, next) {
 		if (dpbp_dev == dpbp) {
-			rte_atomic16_dec(&dpbp_dev->in_use);
+			rte_atomic_store_explicit(&dpbp_dev->in_use, 0,
+						  rte_memory_order_release);
 			return;
 		}
 	}
diff --git a/drivers/bus/fslmc/portal/dpaa2_hw_dpci.c b/drivers/bus/fslmc/portal/dpaa2_hw_dpci.c
index b546da82f6..20371fe062 100644
--- a/drivers/bus/fslmc/portal/dpaa2_hw_dpci.c
+++ b/drivers/bus/fslmc/portal/dpaa2_hw_dpci.c
@@ -135,7 +135,7 @@ rte_dpaa2_create_dpci_device(int vdev_fd __rte_unused,
 	}
 
 	dpci_node->dpci_id = dpci_id;
-	rte_atomic16_init(&dpci_node->in_use);
+	rte_atomic_store_explicit(&dpci_node->in_use, 0, rte_memory_order_relaxed);
 
 	TAILQ_INSERT_TAIL(&dpci_dev_list, dpci_node, next);
 
@@ -159,7 +159,11 @@ struct dpaa2_dpci_dev *rte_dpaa2_alloc_dpci_dev(void)
 
 	/* Get DPCI dev handle from list using index */
 	TAILQ_FOREACH(dpci_dev, &dpci_dev_list, next) {
-		if (dpci_dev && rte_atomic16_test_and_set(&dpci_dev->in_use))
+		uint16_t expected = 0;
+
+		if (rte_atomic_compare_exchange_strong_explicit(&dpci_dev->in_use,
+				&expected, 1, rte_memory_order_acquire,
+				rte_memory_order_relaxed))
 			break;
 	}
 
@@ -174,7 +178,8 @@ void rte_dpaa2_free_dpci_dev(struct dpaa2_dpci_dev *dpci)
 	/* Match DPCI handle and mark it free */
 	TAILQ_FOREACH(dpci_dev, &dpci_dev_list, next) {
 		if (dpci_dev == dpci) {
-			rte_atomic16_dec(&dpci_dev->in_use);
+			rte_atomic_store_explicit(&dpci_dev->in_use, 0,
+						  rte_memory_order_release);
 			return;
 		}
 	}
diff --git a/drivers/bus/fslmc/portal/dpaa2_hw_dpcon.c b/drivers/bus/fslmc/portal/dpaa2_hw_dpcon.c
index 6fd96ec0b9..eff8bc2445 100644
--- a/drivers/bus/fslmc/portal/dpaa2_hw_dpcon.c
+++ b/drivers/bus/fslmc/portal/dpaa2_hw_dpcon.c
@@ -81,7 +81,7 @@ rte_dpaa2_create_dpcon_device(int dev_fd __rte_unused,
 	dpcon_node->qbman_ch_id = attr.qbman_ch_id;
 	dpcon_node->num_priorities = attr.num_priorities;
 	dpcon_node->dpcon_id = dpcon_id;
-	rte_atomic16_init(&dpcon_node->in_use);
+	rte_atomic_store_explicit(&dpcon_node->in_use, 0, rte_memory_order_relaxed);
 
 	TAILQ_INSERT_TAIL(&dpcon_dev_list, dpcon_node, next);
 
@@ -95,7 +95,11 @@ struct dpaa2_dpcon_dev *rte_dpaa2_alloc_dpcon_dev(void)
 
 	/* Get DPCON dev handle from list using index */
 	TAILQ_FOREACH(dpcon_dev, &dpcon_dev_list, next) {
-		if (dpcon_dev && rte_atomic16_test_and_set(&dpcon_dev->in_use))
+		uint16_t expected = 0;
+
+		if (rte_atomic_compare_exchange_strong_explicit(&dpcon_dev->in_use,
+				&expected, 1, rte_memory_order_acquire,
+				rte_memory_order_relaxed))
 			break;
 	}
 
@@ -110,7 +114,8 @@ void rte_dpaa2_free_dpcon_dev(struct dpaa2_dpcon_dev *dpcon)
 	/* Match DPCON handle and mark it free */
 	TAILQ_FOREACH(dpcon_dev, &dpcon_dev_list, next) {
 		if (dpcon_dev == dpcon) {
-			rte_atomic16_dec(&dpcon_dev->in_use);
+			rte_atomic_store_explicit(&dpcon_dev->in_use, 0,
+						  rte_memory_order_release);
 			return;
 		}
 	}
diff --git a/drivers/bus/fslmc/portal/dpaa2_hw_dpio.c b/drivers/bus/fslmc/portal/dpaa2_hw_dpio.c
index e17050b625..9fe449ed38 100644
--- a/drivers/bus/fslmc/portal/dpaa2_hw_dpio.c
+++ b/drivers/bus/fslmc/portal/dpaa2_hw_dpio.c
@@ -352,7 +352,8 @@ static void dpaa2_put_qbman_swp(struct dpaa2_dpio_dev *dpio_dev)
 		 * armed: intr_deinit returns early if intr is not enabled.
 		 */
 		dpaa2_dpio_intr_deinit(dpio_dev);
-		rte_atomic16_clear(&dpio_dev->ref_count);
+		rte_atomic_store_explicit(&dpio_dev->ref_count, 0,
+					  rte_memory_order_release);
 	}
 }
 
@@ -364,7 +365,11 @@ static struct dpaa2_dpio_dev *dpaa2_get_qbman_swp(bool ethrx)
 
 	/* Get DPIO dev handle from list using index */
 	TAILQ_FOREACH(dpio_dev, &dpio_dev_list, next) {
-		if (dpio_dev && rte_atomic16_test_and_set(&dpio_dev->ref_count))
+		uint16_t expected = 0;
+
+		if (rte_atomic_compare_exchange_strong_explicit(&dpio_dev->ref_count,
+				&expected, 1, rte_memory_order_acquire,
+				rte_memory_order_relaxed))
 			break;
 	}
 	if (!dpio_dev) {
@@ -385,7 +390,8 @@ static struct dpaa2_dpio_dev *dpaa2_get_qbman_swp(bool ethrx)
 		ret = dpaa2_configure_stashing(dpio_dev, cpu_id, ethrx);
 		if (ret) {
 			DPAA2_BUS_ERR("dpaa2_configure_stashing failed");
-			rte_atomic16_clear(&dpio_dev->ref_count);
+			rte_atomic_store_explicit(&dpio_dev->ref_count, 0,
+						  rte_memory_order_release);
 			return NULL;
 		}
 	}
@@ -500,7 +506,7 @@ dpaa2_create_dpio_device(int vdev_fd,
 
 	dpio_dev->dpio = NULL;
 	dpio_dev->hw_id = object_id;
-	rte_atomic16_init(&dpio_dev->ref_count);
+	rte_atomic_store_explicit(&dpio_dev->ref_count, 0, rte_memory_order_relaxed);
 	/* Using single portal  for all devices */
 	dpio_dev->mc_portal = dpaa2_get_mcp_ptr(MC_PORTAL_INDEX);
 
diff --git a/drivers/bus/fslmc/portal/dpaa2_hw_pvt.h b/drivers/bus/fslmc/portal/dpaa2_hw_pvt.h
index ef65e7895a..556e1b01c0 100644
--- a/drivers/bus/fslmc/portal/dpaa2_hw_pvt.h
+++ b/drivers/bus/fslmc/portal/dpaa2_hw_pvt.h
@@ -9,6 +9,7 @@
 #define _DPAA2_HW_PVT_H_
 
 #include <rte_compat.h>
+#include <rte_stdatomic.h>
 #include <rte_eventdev.h>
 #include <dpaax_iova_table.h>
 
@@ -112,7 +113,7 @@ struct dpaa2_dpio_dev {
 	TAILQ_ENTRY(dpaa2_dpio_dev) next;
 		/**< Pointer to Next device instance */
 	uint16_t index; /**< Index of a instance in the list */
-	rte_atomic16_t ref_count;
+	RTE_ATOMIC(uint16_t) ref_count;
 		/**< How many thread contexts are sharing this.*/
 	uint16_t eqresp_ci;
 	uint16_t eqresp_pi;
@@ -143,7 +144,7 @@ struct dpaa2_dpbp_dev {
 		/**< Pointer to Next device instance */
 	struct fsl_mc_io dpbp;  /** handle to DPBP portal object */
 	uint16_t token;
-	rte_atomic16_t in_use;
+	RTE_ATOMIC(uint16_t) in_use;
 	uint32_t dpbp_id; /*HW ID for DPBP object */
 };
 
@@ -266,7 +267,7 @@ struct dpaa2_dpci_dev {
 		/**< Pointer to Next device instance */
 	struct fsl_mc_io dpci;  /** handle to DPCI portal object */
 	uint16_t token;
-	rte_atomic16_t in_use;
+	RTE_ATOMIC(uint16_t) in_use;
 	uint32_t dpci_id; /*HW ID for DPCI object */
 	struct dpaa2_queue rx_queue[DPAA2_DPCI_MAX_QUEUES];
 	struct dpaa2_queue tx_queue[DPAA2_DPCI_MAX_QUEUES];
@@ -276,7 +277,7 @@ struct dpaa2_dpcon_dev {
 	TAILQ_ENTRY(dpaa2_dpcon_dev) next;
 	struct fsl_mc_io dpcon;
 	uint16_t token;
-	rte_atomic16_t in_use;
+	RTE_ATOMIC(uint16_t) in_use;
 	uint32_t dpcon_id;
 	uint16_t qbman_ch_id;
 	uint8_t num_priorities;
-- 
2.53.0