Hi,
I'm seeing the CI failure with Arm-gigabyte due to automic_autotest and
malloc_autotest failures.
While this patch is not related to these unit tests since it only modified kni
part, this may be a common CI issue.
Also, would you please have a review about this patch?
Thanks,
Joyce
> -----Original Message-----
> From: dev <dev-boun...@dpdk.org> On Behalf Of Joyce Kong
> Sent: Thursday, August 19, 2021 2:05 PM
> To: ferruh.yi...@intel.com; Honnappa Nagarahalli
> <honnappa.nagaraha...@arm.com>; Ruifeng Wang
> <ruifeng.w...@arm.com>
> Cc: dev@dpdk.org; nd <n...@arm.com>
> Subject: [dpdk-dev] [PATCH] kni: remove non-C11 path from FIFO sync
>
> Non-C11 path was meant to not break build with GCC version < 4.7(when
> C11 atomics were introduced), while now minimum GCC version supported
> by DPDK has been 4.9, C11 atomics support in compiler is no longer a
> problem. So non-C11 path can be removed.
>
> Signed-off-by: Joyce Kong <joyce.k...@arm.com>
> Reviewed-by: Ruifeng Wang <ruifeng.w...@arm.com>
> ---
> lib/kni/rte_kni_common.h | 9 ++------
> lib/kni/rte_kni_fifo.h | 48 +++++++---------------------------------
> 2 files changed, 10 insertions(+), 47 deletions(-)
>
> diff --git a/lib/kni/rte_kni_common.h b/lib/kni/rte_kni_common.h index
> b547ea5501..20d94eaa9b 100644
> --- a/lib/kni/rte_kni_common.h
> +++ b/lib/kni/rte_kni_common.h
> @@ -58,13 +58,8 @@ struct rte_kni_request {
> * Writing should never overwrite the read position
> */
> struct rte_kni_fifo {
> -#ifdef RTE_USE_C11_MEM_MODEL
> - unsigned write; /**< Next position to be written*/
> - unsigned read; /**< Next position to be read */
> -#else
> - volatile unsigned write; /**< Next position to be written*/
> - volatile unsigned read; /**< Next position to be read */
> -#endif
> + unsigned write; /**< Next position to be written*/
> + unsigned read; /**< Next position to be read */
> unsigned len; /**< Circular buffer length */
> unsigned elem_size; /**< Pointer size - for 32/64 bit OS */
> void *volatile buffer[]; /**< The buffer contains mbuf pointers */
> diff --git a/lib/kni/rte_kni_fifo.h b/lib/kni/rte_kni_fifo.h index
> d2ec82fe87..057f6b3ded 100644
> --- a/lib/kni/rte_kni_fifo.h
> +++ b/lib/kni/rte_kni_fifo.h
> @@ -2,38 +2,6 @@
> * Copyright(c) 2010-2014 Intel Corporation
> */
>
> -
> -
> -/**
> - * @internal when c11 memory model enabled use c11 atomic memory
> barrier.
> - * when under non c11 memory model use rte_smp_* memory barrier.
> - *
> - * @param src
> - * Pointer to the source data.
> - * @param dst
> - * Pointer to the destination data.
> - * @param value
> - * Data value.
> - */
> -#ifdef RTE_USE_C11_MEM_MODEL
> -#define __KNI_LOAD_ACQUIRE(src) ({ \
> - __atomic_load_n((src), __ATOMIC_ACQUIRE); \
> - })
> -#define __KNI_STORE_RELEASE(dst, value) do { \
> - __atomic_store_n((dst), value, __ATOMIC_RELEASE); \
> - } while(0)
> -#else
> -#define __KNI_LOAD_ACQUIRE(src) ({ \
> - typeof (*(src)) val = *(src); \
> - rte_smp_rmb(); \
> - val; \
> - })
> -#define __KNI_STORE_RELEASE(dst, value) do { \
> - *(dst) = value; \
> - rte_smp_wmb(); \
> - } while(0)
> -#endif
> -
> /**
> * Initializes the kni fifo structure
> */
> @@ -59,7 +27,7 @@ kni_fifo_put(struct rte_kni_fifo *fifo, void **data,
> unsigned num)
> unsigned i = 0;
> unsigned fifo_write = fifo->write;
> unsigned new_write = fifo_write;
> - unsigned fifo_read = __KNI_LOAD_ACQUIRE(&fifo->read);
> + unsigned fifo_read = __atomic_load_n(&fifo->read,
> __ATOMIC_ACQUIRE);
>
> for (i = 0; i < num; i++) {
> new_write = (new_write + 1) & (fifo->len - 1); @@ -69,7
> +37,7 @@ kni_fifo_put(struct rte_kni_fifo *fifo, void **data, unsigned num)
> fifo->buffer[fifo_write] = data[i];
> fifo_write = new_write;
> }
> - __KNI_STORE_RELEASE(&fifo->write, fifo_write);
> + __atomic_store_n(&fifo->write, fifo_write, __ATOMIC_RELEASE);
> return i;
> }
>
> @@ -81,7 +49,7 @@ kni_fifo_get(struct rte_kni_fifo *fifo, void **data,
> unsigned num) {
> unsigned i = 0;
> unsigned new_read = fifo->read;
> - unsigned fifo_write = __KNI_LOAD_ACQUIRE(&fifo->write);
> + unsigned fifo_write = __atomic_load_n(&fifo->write,
> __ATOMIC_ACQUIRE);
>
> for (i = 0; i < num; i++) {
> if (new_read == fifo_write)
> @@ -90,7 +58,7 @@ kni_fifo_get(struct rte_kni_fifo *fifo, void **data,
> unsigned num)
> data[i] = fifo->buffer[new_read];
> new_read = (new_read + 1) & (fifo->len - 1);
> }
> - __KNI_STORE_RELEASE(&fifo->read, new_read);
> + __atomic_store_n(&fifo->read, new_read, __ATOMIC_RELEASE);
> return i;
> }
>
> @@ -100,8 +68,8 @@ kni_fifo_get(struct rte_kni_fifo *fifo, void **data,
> unsigned num) static inline uint32_t kni_fifo_count(struct rte_kni_fifo
> *fifo)
> {
> - unsigned fifo_write = __KNI_LOAD_ACQUIRE(&fifo->write);
> - unsigned fifo_read = __KNI_LOAD_ACQUIRE(&fifo->read);
> + unsigned fifo_write = __atomic_load_n(&fifo->write,
> __ATOMIC_ACQUIRE);
> + unsigned fifo_read = __atomic_load_n(&fifo->read,
> __ATOMIC_ACQUIRE);
> return (fifo->len + fifo_write - fifo_read) & (fifo->len - 1); }
>
> @@ -111,7 +79,7 @@ kni_fifo_count(struct rte_kni_fifo *fifo) static inline
> uint32_t kni_fifo_free_count(struct rte_kni_fifo *fifo) {
> - uint32_t fifo_write = __KNI_LOAD_ACQUIRE(&fifo->write);
> - uint32_t fifo_read = __KNI_LOAD_ACQUIRE(&fifo->read);
> + uint32_t fifo_write = __atomic_load_n(&fifo->write,
> __ATOMIC_ACQUIRE);
> + uint32_t fifo_read = __atomic_load_n(&fifo->read,
> __ATOMIC_ACQUIRE);
> return (fifo_read - fifo_write - 1) & (fifo->len - 1); }
> --
> 2.17.1
