Commit 644fc120 authored by Richael Zhuang's avatar Richael Zhuang Committed by Tomasz Zawadzki
Browse files

nvmf: upgrade to C11 atomics 



Replace legacy __sync builtins with C11 __atomic ones to leverage fine
memory order controlling.

Signed-off-by: default avatarRichael Zhuang <richael.zhuang@arm.com>
Change-Id: I8a1e976be6a0db73af4451a39a8f544310c72989
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/463458


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: Broadcom SPDK FC-NVMe CI <spdk-ci.pdl@broadcom.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
Reviewed-by: default avatarBroadcom SPDK FC-NVMe CI <spdk-ci.pdl@broadcom.com>
Reviewed-by: default avatarDarek Stojaczyk <dariusz.stojaczyk@intel.com>
parent 1399a42b

lib/nvmf/rdma.c

+1 −1
Original line number Diff line number Diff line
@@ -2822,7 +2822,7 @@ _nvmf_rdma_try_disconnect(void *ctx) 
static inline void

spdk_nvmf_rdma_start_disconnect(struct spdk_nvmf_rdma_qpair *rqpair)

{

	if (__sync_bool_compare_and_swap(&rqpair->disconnect_started, false, true)) {

	if (!__atomic_test_and_set(&rqpair->disconnect_started, __ATOMIC_RELAXED)) {

		_nvmf_rdma_try_disconnect(&rqpair->qpair);

	}

}

lib/nvmf/subsystem.c

+8 −3
Original line number Diff line number Diff line
@@ -376,6 +376,7 @@ spdk_nvmf_subsystem_set_state(struct spdk_nvmf_subsystem *subsystem, 
			      enum spdk_nvmf_subsystem_state state)

{

	enum spdk_nvmf_subsystem_state actual_old_state, expected_old_state;

	bool exchanged;



	switch (state) {

	case SPDK_NVMF_SUBSYSTEM_INACTIVE:
@@ -404,8 +405,10 @@ spdk_nvmf_subsystem_set_state(struct spdk_nvmf_subsystem *subsystem, 
		return -1;

	}



	actual_old_state = __sync_val_compare_and_swap(&subsystem->state, expected_old_state, state);

	if (actual_old_state != expected_old_state) {

	actual_old_state = expected_old_state;

	exchanged = __atomic_compare_exchange_n(&subsystem->state, &actual_old_state, state, false,

						__ATOMIC_RELAXED, __ATOMIC_RELAXED);

	if (spdk_unlikely(exchanged == false)) {

		if (actual_old_state == SPDK_NVMF_SUBSYSTEM_RESUMING &&

		    state == SPDK_NVMF_SUBSYSTEM_ACTIVE) {

			expected_old_state = SPDK_NVMF_SUBSYSTEM_RESUMING;
@@ -415,7 +418,9 @@ spdk_nvmf_subsystem_set_state(struct spdk_nvmf_subsystem *subsystem, 
		    state == SPDK_NVMF_SUBSYSTEM_DEACTIVATING) {

			expected_old_state = SPDK_NVMF_SUBSYSTEM_ACTIVATING;

		}

		actual_old_state = __sync_val_compare_and_swap(&subsystem->state, expected_old_state, state);

		actual_old_state = expected_old_state;

		__atomic_compare_exchange_n(&subsystem->state, &actual_old_state, state, false,

					    __ATOMIC_RELAXED, __ATOMIC_RELAXED);

	}

	assert(actual_old_state == expected_old_state);

	return actual_old_state - expected_old_state;