Commit 094e980d authored by Jim Harris's avatar Jim Harris
Browse files

trace: detect out of shared memory 



Now that we do not unlink shared memory trace files
if the user has specified tracepoint flags, it is
possible to run out of shm space.

Signed-off-by: default avatarJim Harris <james.r.harris@intel.com>
Change-Id: I713eb15a4067969ffcb6c95009c589d8e71e8d55

Reviewed-on: https://review.gerrithub.io/424356


Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
Reviewed-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: default avatarChangpeng Liu <changpeng.liu@intel.com>
Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Chandler-Test-Pool: SPDK Automated Test System <sys_sgsw@intel.com>
parent b7b7c046

lib/trace/trace.c

+18 −0
Original line number Diff line number Diff line
@@ -102,6 +102,20 @@ spdk_trace_init(const char *shm_name) 
		goto trace_init_err;

	}



	/* TODO: On FreeBSD, mlock on shm_open'd memory doesn't seem to work.  Docs say that kern.ipc.shm_use_phys=1

	 * should allow it, but forcing that doesn't seem to work either.  So for now just skip mlock on FreeBSD

	 * altogether.

	 */

#if defined(__linux__)

	if (mlock(g_trace_histories, sizeof(*g_trace_histories)) != 0) {

		fprintf(stderr, "Could not mlock shm for tracing - %s.\n", spdk_strerror(errno));

		if (errno == ENOMEM) {

			fprintf(stderr, "Check /dev/shm for old tracing files that can be deleted.\n");

		}

		goto trace_init_err;

	}

#endif



	memset(g_trace_histories, 0, sizeof(*g_trace_histories));



	g_trace_flags = &g_trace_histories->flags;
@@ -117,9 +131,13 @@ spdk_trace_init(const char *shm_name) 
	return 0;



trace_init_err:

	if (g_trace_histories != MAP_FAILED) {

		munmap(g_trace_histories, sizeof(*g_trace_histories));

	}

	close(g_trace_fd);

	g_trace_fd = -1;

	shm_unlink(shm_name);

	g_trace_histories = NULL;



	return 1;