stack: reload head when pop fails (generic)

Message ID (mailing list archive)
State Superseded, archived
Delegated to: Thomas Monjalon
Series stack: reload head when pop fails (generic) |


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

Commit Message

Julien Meunier Aug. 19, 2021, 9:39 a.m. UTC
  The previous fix 18effad9cfa7 ("stack: reload head when pop fails") only
changed C11 implementation, not generic implementation.

List head must be loaded right before continue (when failed to find the
new head). Without this, one thread might keep trying and failing to pop
items without ever loading the new correct head.

Fixes: 3340202f5954 ("stack: add lock-free implementation")

Signed-off-by: Julien Meunier <>
 lib/stack/rte_stack_lf_generic.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)


diff --git a/lib/stack/rte_stack_lf_generic.h b/lib/stack/rte_stack_lf_generic.h
index 4850a05ee7..7fa29cedb2 100644
--- a/lib/stack/rte_stack_lf_generic.h
+++ b/lib/stack/rte_stack_lf_generic.h
@@ -128,8 +128,10 @@  __rte_stack_lf_pop_elems(struct rte_stack_lf_list *list,
 		/* If NULL was encountered, the list was modified while
 		 * traversing it. Retry.
-		if (i != num)
+		if (i != num) {
+			old_head = list->head;
+		} = tmp;
 		new_head.cnt = old_head.cnt + 1;