tc: create helper to access toolchain tools

README.adoc

@@ -924,8 +924,7 @@ so it is close to the failing `0xbf0000cc`.
 `readelf`:
 
 ....
-./out/x86_64/buildroot/host/usr/bin/x86_64-buildroot-linux-uclibc-readelf \
+./runtc readelf -s ./out/x86_64/buildroot/build/kernel_module-1.0/hello.ko
--s ./out/x86_64/buildroot/build/kernel_module-1.0/hello.ko
 ....
 
 does not give any interesting hits at `cc`, no symbol was placed that far.
@@ -998,7 +997,7 @@ The base address shows on terminal:
 Now let's find the offset of `myinit`:
 
 ....
-./out/x86_64/buildroot/host/usr/bin/x86_64-buildroot-linux-uclibc-readelf \
+./runtc readelf \
   -s ./out/x86_64/buildroot/build/kernel_module-1.0/fops.ko | \
   grep myinit
 ....
@@ -1295,7 +1294,7 @@ Cannot access memory at address 0x10604
 We have also double checked the address with:
 
 ....
-./out/arm/buildroot/host/bin/arm-buildroot-linux-uclibcgnueabi-readelf-s \
+./runtc -a arm readelf \
   ./out/arm/buildroot/build/kernel_module-1.0/user/hello.out | \
   grep main
 ....
@@ -2737,7 +2736,7 @@ Notes:
 It can be found from:
 +
 ....
-readelf -e out/x86_64/buildroot/build/linux-*/vmlinux | grep Entry
+./runtc readelf -e out/x86_64/buildroot/build/linux-*/vmlinux | grep Entry
 ....
 +
 TODO confirm further. If I try to break there with:

build

@@ -9,7 +9,6 @@ touch "$br2_cli_file"
 configure=true
 config_fragments="${root_dir}/br2"
 extra_make_args=
-gem5=false
 j="$(nproc)"
 linux_reconfigure=false
 linux_kernel_custom_config_file=

common

@@ -49,3 +49,4 @@ if [ -f "$f" ]; then
 fi
 # Default arch.
 arch=x86_64
+gem5=false

run

@@ -18,7 +18,6 @@ extra_append='console_msg_format=syslog nokaslr norandmaps printk.devkmsg=on pri
 extra_append_after_dash=
 extra_flags=
 extra_flags_qemu=
-gem5=false
 gem5opts=
 lkmc_eval=
 initrd=false

rungdb

@@ -4,7 +4,6 @@ set -eu
 set -- ${cli_rungdb:-} "$@"
 after=
 before=
-gem5=false
 lx_symbols="-ex 'lx-symbols ../kernel_module-1.0/' \\
 "
 kgdb=false

rungdb-user

@@ -3,7 +3,6 @@ set -eu
 . common
 set -- ${cli_rungdb_user:-} "$@"
 usage="$0 <exec-relative-path> [<brk-symbol>]"
-gem5=false
 gem5_opt=
 while getopts a:gh OPT; do
   case "$OPT" in
@@ -34,8 +33,7 @@ else
 fi
 set_common_vars "$arch" "$gem5"
 executable="${build_dir}/${executable_rel}"
-readelf="${host_dir}/usr/bin/${arch}-linux-readelf"
+addr="$("${root_dir}/runtc" readelf -h "$executable" | awk '/Entry/{ print $NF }' )"
-addr="$("$readelf" -h "$executable" | awk '/Entry/{ print $NF }' )"
 ex="-ex \"add-symbol-file $executable $addr\""
 # -L or else lx-symbols throws for arm:
 # gdb.MemoryError: Cannot access memory at address 0xbf0040cc

rungdbserver

@@ -2,7 +2,6 @@
 set -eu
 . common
 set -- ${cli_rungdbserver:-} "$@"
-gem5=false
 while getopts a:g OPT; do
   case "$OPT" in
     a)

runtc

@@ -0,0 +1,28 @@
+#!/usr/bin/env bash
+set -eu
+. common
+set -- ${cli_tc:-} "$@"
+while getopts a:gh OPT; do
+  case "$OPT" in
+    a)
+      arch="$OPTARG"
+      ;;
+    g)
+      gem5=true
+      ;;
+    h)
+      printf "Usage: $0 TOOL [TOOL_ARGS]...
+Call a built ToolChain tool. Example:
+
+    $0 -a arm readelf -h
+" 2>&1
+      exit 0
+      ;;
+  esac
+done
+shift "$(($OPTIND - 1))"
+tool="$1"
+shift
+set_common_vars "$arch" "$gem5"
+"${buildroot_out_dir}/host/bin/"*-buildroot-*"${tool}" "$@"
+exit "$?"

trace-boot

@@ -17,7 +17,7 @@ time ./qemu-trace2txt -a "$arch"
 # We could put this on a separate script, but it just adds more arch boilerplate to a new script.
 # So let's just leave it here for now since it did not add a significant processing time.
 echo "instructions $(wc -l "${qemu_trace_txt_file}" | cut -d' ' -f1)"
-entry_addr=$("${host_dir}"/bin/*-buildroot-*-readelf -h "${build_dir}/linux-custom/vmlinux" | grep 'Entry point address' | sed -E 's/.*: *//')
+entry_addr=$("${root_dir}/runtc" readelf -h "${build_dir}/linux-custom/vmlinux" | grep 'Entry point address' | sed -E 's/.*: *//')
 echo "entry_address ${entry_addr}"
 sed "/${entry_addr}/q" "${qemu_trace_txt_file}" >"${qemu_out_dir}/trace-boot.txt"
 echo "instructions_firmware $(wc -l "${qemu_out_dir}/trace-boot.txt" | cut -d' ' -f1)"