[PATCH v8 12/25] bus/fslmc: replace rte_atomic with stdatomic
From: Stephen Hemminger <stephen@networkplumber.org>
Date: 2026-09-17 20:12:35
Subsystem:
the rest · Maintainer:
Linus Torvalds
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@networkplumber.org> Acked-by: Hemant Agrawal <redacted> --- 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 +++++---- drivers/bus/fslmc/qbman/include/compat.h | 18 ++++++------------ 6 files changed, 45 insertions(+), 29 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;
diff --git a/drivers/bus/fslmc/qbman/include/compat.h b/drivers/bus/fslmc/qbman/include/compat.h
index 5a57bd8ed1..c933cb328a 100644
--- a/drivers/bus/fslmc/qbman/include/compat.h
+++ b/drivers/bus/fslmc/qbman/include/compat.h@@ -81,18 +81,12 @@ do { \ #define dma_wmb() rte_io_wmb() -#define atomic_t rte_atomic32_t -#define atomic_read(v) rte_atomic32_read(v) -#define atomic_set(v, i) rte_atomic32_set(v, i) +typedef RTE_ATOMIC(uint32_t) atomic_t; -#define atomic_inc(v) rte_atomic32_add(v, 1) -#define atomic_dec(v) rte_atomic32_sub(v, 1) - -#define atomic_inc_and_test(v) rte_atomic32_inc_and_test(v) -#define atomic_dec_and_test(v) rte_atomic32_dec_and_test(v) - -#define atomic_inc_return(v) rte_atomic32_add_return(v, 1) -#define atomic_dec_return(v) rte_atomic32_sub_return(v, 1) -#define atomic_sub_and_test(i, v) (rte_atomic32_sub_return(v, i) == 0) +#define atomic_set(v, i) rte_atomic_store_explicit((v), (i), rte_memory_order_relaxed) +#define atomic_inc(v) ((void)rte_atomic_fetch_add_explicit((v), 1, \ + rte_memory_order_seq_cst)) +#define atomic_dec_and_test(v) (rte_atomic_fetch_sub_explicit((v), 1, \ + rte_memory_order_seq_cst) == 1) #endif /* HEADER_COMPAT_H */
--
2.53.0