d/numam-dpdk
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

stack: fix inconsistent weak/strong CAS

Browse Source 
Fix cmpexchange usage of weak / strong.
The generated code is the same on x86 and ARM (there is no weak
cmpexchange), but the old usage was inconsistent.
For push and pop update size, weak is used because cmpexchange is inside
a loop.
For pop update root, strong is used even though cmpexchange is inside a
loop, because there may be a lot of operations to do in a loop iteration
(locate the new head).

Signed-off-by: Steven Lariau <steven.lariau@arm.com>
Reviewed-by: Dharmik Thakkar <dharmik.thakkar@arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
Acked-by: Gage Eads <gage.eads@intel.com>
This commit is contained in:
Steven Lariau 2020-09-25 18:43:35 +01:00 committed by David Marchand
parent c51e67c2ee
commit 0df8e2d2c9
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
lib/librte_stack/rte_stack_lf_c11.h
View File

@ -96,7 +96,7 @@ __rte_stack_lf_pop_elems(struct rte_stack_lf_list *list,
/* len is updated on failure */
if (__atomic_compare_exchange_n(&list->len,
&len, len - num,
0, __ATOMIC_ACQUIRE,
1, __ATOMIC_ACQUIRE,
__ATOMIC_ACQUIRE))
break;
}
@ -149,7 +149,7 @@ __rte_stack_lf_pop_elems(struct rte_stack_lf_list *list,
(rte_int128_t *)&list->head,
(rte_int128_t *)&old_head,
(rte_int128_t *)&new_head,
1, __ATOMIC_RELEASE,
0, __ATOMIC_RELEASE,
__ATOMIC_RELAXED);
} while (success == 0);