+function true_loop_cpu0()
+{
+ # Generate many system call events (fill buffers) on CPU 0
+ for a in $(seq 1 $1); do
+ taskset 0x00000001 /bin/true;
+ done
+}
+
+function test_kernel_local_snapshot_discard ()
+{
+ diag "Test local kernel snapshots with small discard buffers"
+ create_lttng_session_no_output $SESSION_NAME
+ enable_lttng_mmap_discard_small_kernel_channel $SESSION_NAME \
+ $CHANNEL_NAME
+ lttng_enable_kernel_syscall_ok $SESSION_NAME -a $CHANNEL_NAME
+ start_lttng_tracing_ok $SESSION_NAME
+ lttng_snapshot_add_output_ok $SESSION_NAME $TRACE_PATH
+
+ true_loop_cpu0 10000
+
+ # Take first snapshot, remember first line.
+ lttng_snapshot_record $SESSION_NAME
+ FIRST_LINE="$(trace_first_line $TRACE_PATH/)"
+ diag "First line (1st snapshot): $FIRST_LINE"
+
+ rm -rf $TRACE_PATH
+
+ true_loop_cpu0 10000
+
+ # Take 2nd snapshot, compare first line. In discard mode, they
+ # should still be the same.
+ lttng_snapshot_record $SESSION_NAME
+ FIRST_LINE_2="$(trace_first_line $TRACE_PATH/)"
+ diag "First line (2nd snapshot): $FIRST_LINE"
+ rm -rf $TRACE_PATH
+
+ if [ x"$FIRST_LINE" != x"$FIRST_LINE_2" ]; then
+ fail "First snapshot event do not match."
+ else
+ pass "First snapshot event match."
+ fi
+
+ stop_lttng_tracing_ok $SESSION_NAME
+ destroy_lttng_session_ok $SESSION_NAME
+}
+
+function test_kernel_local_snapshot_overwrite_small_buffers ()
+{
+ diag "Test local kernel snapshot with small overwrite buffers"
+ create_lttng_session_no_output $SESSION_NAME
+ enable_lttng_mmap_overwrite_small_kernel_channel $SESSION_NAME \
+ $CHANNEL_NAME
+ lttng_enable_kernel_syscall_ok $SESSION_NAME -a $CHANNEL_NAME
+ start_lttng_tracing_ok $SESSION_NAME
+ lttng_snapshot_add_output_ok $SESSION_NAME $TRACE_PATH
+
+ true_loop_cpu0 10000
+
+ # Take first snapshot, remember first line.
+ lttng_snapshot_record $SESSION_NAME
+ FIRST_LINE="$(trace_first_line $TRACE_PATH/)"
+ diag "First line (1st snapshot): $FIRST_LINE"
+
+ rm -rf $TRACE_PATH
+
+ true_loop_cpu0 10000
+
+ # Take 2nd snapshot, compare first line. In overwrite mode, they
+ # WILL be different.
+ lttng_snapshot_record $SESSION_NAME
+ FIRST_LINE_2="$(trace_first_line $TRACE_PATH/)"
+ diag "First line (2nd snapshot): $FIRST_LINE_2"
+ rm -rf $TRACE_PATH
+
+ if [ x"$FIRST_LINE" != x"$FIRST_LINE_2" ]; then
+ pass "First snapshot event do not match."
+ else
+ fail "First snapshot event match."
+ fi
+
+ stop_lttng_tracing_ok $SESSION_NAME
+ destroy_lttng_session_ok $SESSION_NAME
+}
+