[v1] gpudev: remove unnecessary rte_gpu_wmb

Message ID 20211125224054.26157-1-eagostini@nvidia.com (mailing list archive)
State Accepted, archived
Delegated to: Thomas Monjalon
Headers
Series [v1] gpudev: remove unnecessary rte_gpu_wmb |

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/Intel-compilation success Compilation OK
ci/intel-Testing success Testing PASS
ci/github-robot: build success github build: passed
ci/iol-broadcom-Performance success Performance Testing PASS
ci/iol-mellanox-Performance success Performance Testing PASS
ci/iol-broadcom-Functional success Functional Testing PASS
ci/iol-intel-Functional fail Functional Testing issues
ci/iol-intel-Performance success Performance Testing PASS
ci/iol-x86_64-unit-testing success Testing PASS
ci/iol-x86_64-compile-testing success Testing PASS
ci/iol-aarch64-unit-testing success Testing PASS
ci/iol-aarch64-compile-testing success Testing PASS

Commit Message

Elena Agostini Nov. 25, 2021, 10:40 p.m. UTC
  From: Elena Agostini <eagostini@nvidia.com>

Remove unnecessary rte_gpu_wmb from rte_gpu_comm_populate_list_pkts.
It causes a performance degradation in case of NVIDIA GPU V100.

This change doesn't affect any functionality as the status resides
in CPU registered memory.

Fixes: c7ebd65c1372 ("gpudev: add communication list")

Signed-off-by: Elena Agostini <eagostini@nvidia.com>
---
 lib/gpudev/gpudev.c | 1 -
 1 file changed, 1 deletion(-)
  

Comments

Thomas Monjalon Nov. 26, 2021, 11:29 a.m. UTC | #1
25/11/2021 23:40, eagostini@nvidia.com:
> From: Elena Agostini <eagostini@nvidia.com>
> 
> Remove unnecessary rte_gpu_wmb from rte_gpu_comm_populate_list_pkts.
> It causes a performance degradation in case of NVIDIA GPU V100.
> 
> This change doesn't affect any functionality as the status resides
> in CPU registered memory.
> 
> Fixes: c7ebd65c1372 ("gpudev: add communication list")
> 
> Signed-off-by: Elena Agostini <eagostini@nvidia.com>

Applied, thanks.
  

Patch

diff --git a/lib/gpudev/gpudev.c b/lib/gpudev/gpudev.c
index 1d8200e71b..9ae36dbae9 100644
--- a/lib/gpudev/gpudev.c
+++ b/lib/gpudev/gpudev.c
@@ -877,7 +877,6 @@  rte_gpu_comm_populate_list_pkts(struct rte_gpu_comm_list *comm_list_item,
 	RTE_GPU_VOLATILE(comm_list_item->num_pkts) = num_mbufs;
 	rte_gpu_wmb(comm_list_item->dev_id);
 	RTE_GPU_VOLATILE(comm_list_item->status) = RTE_GPU_COMM_LIST_READY;
-	rte_gpu_wmb(comm_list_item->dev_id);
 
 	return 0;
 }