Add overflow and normal kernel nOS-V tests

test/rt/nosv/CMakeLists.txt

@@ -66,7 +66,8 @@ nosv_test(several-tasks.c SORT NAME several-tasks-breakdown-level-4 LEVEL 4 BREA
 include(CheckPerfParanoid)
 if (PERF_PARANOID_KERNEL)
   message(STATUS "Enabling perf paranoid tests for nOS-V")
-  nosv_test(overflow-kernel-ring.c DRIVER "overflow-kernel-ring.driver.sh")
+  nosv_test(kernel.c NAME kernel-overflow DRIVER "kernel-overflow.driver.sh")
+  nosv_test(kernel.c NAME kernel-normal   DRIVER "kernel-normal.driver.sh")
 elseif(ENABLE_ALL_TESTS)
   message(FATAL_ERROR "Cannot enable perf paranoid tests for nOS-V")
 else()

test/rt/nosv/kernel-overflow.driver.sh

@@ -0,0 +1,47 @@
+target=$OVNI_TEST_BIN
+
+# We will set our own
+unset NOSV_CONFIG
+unset NOSV_CONFIG_OVERRIDE
+
+export NOSV_APPID=1
+
+# Small kernel ring size to make execution fast
+ringsize=$((64*1024))
+
+# Each CS event pair occupies 16 bytes.
+cspair=32
+
+# How many CS event pairs fit in the ring buffer?
+navail=$(($ringsize / $cspair))
+
+# For the test, write 8 times the ring buffer
+ncs=$((8 * $navail))
+
+# Flush the kernel after overflowing the ring buffer, by writing to it twice the
+# ring size
+nflush=$((2 * $ringsize / $cspair))
+
+cat > nosv.toml << EOF
+instrumentation.version = "ovni"
+ovni.level = 3
+ovni.kernel_ringsize = ${ringsize}
+EOF
+
+$target $ncs $nflush 2>&1 | tee err.log
+
+# Ensure no nOS-V warnings at runtime
+if grep -c "cannot enable kernel events" err.log; then
+  echo "cannot enable kernel events in all threads" >&2
+  exit 1
+fi
+
+# We need to sort the trace as it has unsorted regions
+ovnisort ovni
+
+# Ensure we have at least the number of context switches we caused, and ensure
+# the number of "in" and "out" events match.
+ovnitop ovni | awk '{n[$1] = $2} END { if (n["KCO"] != n["KCI"] || n["KCO"] < '$ncs') exit 1 }'
+
+# Run the emulator
+ovniemu -l ovni