Commit 15a7b105 authored by Konrad Sztyber's avatar Konrad Sztyber Committed by Jim Harris
Browse files

nvmf: protect subsystem->changing_state with a mutex 



We'll want to do more in this critical section concurrently, so an
atomic operation won't be enough.

Signed-off-by: default avatarKonrad Sztyber <konrad.sztyber@intel.com>
Change-Id: Iae826ba0b0c4236336d1eac2f0e8df6271bc47cf
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/22938


Community-CI: Mellanox Build Bot
Reviewed-by: default avatarAleksey Marchuk <alexeymar@nvidia.com>
Reviewed-by: default avatarJim Harris <jim.harris@samsung.com>
Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
parent 8de19363

lib/nvmf/subsystem.c

+9 −1
Original line number Diff line number Diff line
@@ -568,7 +568,10 @@ nvmf_subsystem_state_change_complete(struct nvmf_subsystem_state_change_ctx *ctx 
{

	struct spdk_nvmf_subsystem *subsystem = ctx->subsystem;



	pthread_mutex_lock(&subsystem->mutex);

	subsystem->changing_state = false;

	pthread_mutex_unlock(&subsystem->mutex);



	if (ctx->cb_fn != NULL) {

		ctx->cb_fn(subsystem, ctx->cb_arg, status);

	}
@@ -695,11 +698,16 @@ nvmf_subsystem_state_change(struct spdk_nvmf_subsystem *subsystem, 
	ctx->cb_fn = cb_fn;

	ctx->cb_arg = cb_arg;



	if (__sync_val_compare_and_swap(&subsystem->changing_state, false, true)) {

	pthread_mutex_lock(&subsystem->mutex);

	if (subsystem->changing_state) {

		pthread_mutex_unlock(&subsystem->mutex);

		free(ctx);

		return -EBUSY;

	}



	subsystem->changing_state = true;

	pthread_mutex_unlock(&subsystem->mutex);



	SPDK_DTRACE_PROBE3(nvmf_subsystem_change_state, subsystem->subnqn,

			   requested_state, subsystem->state);

	/* If we are already in the requested state, just call the callback immediately. */