filter output option

README.md

@@ -152,6 +152,7 @@ Both `nanoBench.sh` and `kernel-nanoBench.sh` support the following command-line
 | `-basic_mode`                | The effect of this option is described in the [Generated Code](#generated-code) section. |
 | `-no_mem`                    | If this option is enabled, the code for `read_perf_ctrs` does not make any memory accesses and stores all performance counter values in registers. This can, for example, be useful for benchmarks that require that the state of the data caches does not change after the execution of `code_init`. *If this option is used, the code to be benchmarked must not modify registers* ***R8-R11 (Intel)*** *and* ***R8-R13 (AMD).*** *Furthermore, `read_perf_ctrs` will modify* ***RAX, RCX, and RDX***. |
 | `-no_normalization`          | If this option is enabled, the measurement results are not divided by the number of repetitions. |
+| `-remove_empty_events`       | If this option is enabled, the output does not contain events that did not occur. |
 | `-df`                        | If this option is enabled, the front-end buffers are drained after `code_init`, after `code_late_init`, and after the last instance of `code` by executing an lfence, followed by a long sequence of 1-Byte `NOP` instructions, followed by a long sequence of 15-Byte `NOP` instructions. |
 | `-cpu <n>`                   | Pins the measurement thread to CPU n. `[Default: Pin the thread to the CPU it is currently running on.]` |
 | `-verbose`                   | Outputs the results of all performance counter readings. In the user-space version, the results are printed to stdout. The output of the kernel module can be accessed using `dmesg`. |

kernel-nanoBench.sh

@@ -21,6 +21,7 @@ fi
 cat /sys/nb/reset
 
 taskset=""
+filter_output="cat"
 
 while [ "$1" ]; do
     if [[ "$1" == -asm_i* ]]; then
@@ -109,6 +110,9 @@ while [ "$1" ]; do
     elif [[ "$1" == -avg* ]]; then
         echo "avg" > /sys/nb/agg
         shift
+    elif [[ "$1" == -r* ]]; then
+        filter_output="grep -v 0.00"
+        shift
     elif [[ "$1" == -h* ]]; then
         echo "kernel-nanoBench.sh usage:"
         echo
@@ -134,6 +138,7 @@ while [ "$1" ]; do
         echo "  -basic_mode:                Enables basic mode."
         echo "  -no_mem:                    The code for reading the perf. ctrs. does not make memory accesses."
         echo "  -no_normalization:          The measurement results are not divided by the number of repetitions."
+        echo "  -remove_empty_events:       Removes events from the output that did not occur."
         echo "  -cpu <n>:                   Pins the measurement thread to CPU n."
         echo "  -verbose:                   Outputs the results of all performance counter readings."
         exit 0
@@ -146,6 +151,9 @@ done
 prev_nmi_watchdog=$(cat /proc/sys/kernel/nmi_watchdog)
 [ $prev_nmi_watchdog != 0 ] && echo 0 > /proc/sys/kernel/nmi_watchdog
 
-$taskset cat /proc/nanoBench
+$taskset cat /proc/nanoBench | $filter_output
+return_value=${PIPESTATUS[0]}
 
 [ $prev_nmi_watchdog != 0 ] && echo $prev_nmi_watchdog > /proc/sys/kernel/nmi_watchdog
+
+exit $return_value

nanoBench.sh

@@ -18,15 +18,11 @@ if [ $(cat /sys/devices/system/cpu/smt/active) -ne 0 ]; then
     echo "Note: Hyper-threading is enabled; it can be disabled with \"sudo ./disable-HT.sh\"" >&2
 fi
 
-debug=false
-for p in "$@"; do
-    if [[ "$p" == -de* ]]; then
-        debug=true
-    fi
-done
+debug=""
+filter_output="cat"
 
 args=''
-while [ "$2" ]; do
+while [ "$1" ]; do
     if [[ "$1" == -asm_i* ]]; then
         assemble "$2" asm-init.bin
         args="$args -code_init asm-init.bin"
@@ -43,12 +39,18 @@ while [ "$2" ]; do
         assemble "$2" asm-code.bin
         args="$args -code asm-code.bin"
         shift 2
+    elif [[ "$1" == -de* ]]; then
+        debug="gdb -ex=run --args"
+        args="$args $1"
+        shift
+    elif [[ "$1" == -r* ]]; then
+        filter_output="grep -v 0.00"
+        shift
     else
         args="$args $1"
         shift
     fi
 done
-args="$args $1"
 set "$args"
 
 if [ -d "/sys/bus/event_source/devices/cpu" ]; then
@@ -74,13 +76,8 @@ iTCO_vendor_support_prev_loaded=$?
 prev_nmi_watchdog=$(cat /proc/sys/kernel/nmi_watchdog)
 [ $prev_nmi_watchdog != 0 ] && echo 0 > /proc/sys/kernel/nmi_watchdog
 
-if [ "$debug" = true ]; then
-    gdb -ex=run --args user/nanoBench $@
-    return_value=$?
-else
-    user/nanoBench $@
-    return_value=$?
-fi
+$debug user/nanoBench $@ | $filter_output
+return_value=${PIPESTATUS[0]}
 
 rm -f asm-*.bin
 
@@ -104,4 +101,5 @@ fi
 if [[ $iTCO_vendor_support_prev_loaded != 0 ]]; then
     modprobe iTCO_vendor_support &>/dev/null
 fi
+
 exit $return_value