tools build: Fix rust cross compilation

Currently no target is specified to compile rust code when needed, which
breaks cross compilation. E.g. for arm64:

      LD      /tmp/build/tests/workloads/perf-test-in.o
    aarch64-linux-gnu-ld: /tmp/build/tests/workloads/code_with_type.a(code_with_type.code_with_type.d12f4324cb53c560-cgu.0.rcgu.o): Relocations in generic ELF (EM: 62)
    aarch64-linux-gnu-ld: /tmp/build/tests/workloads/code_with_type.a(code_with_type.code_with_type.d12f4324cb53c560-cgu.0.rcgu.o): Relocations in generic ELF (EM: 62)
    [...repeated...]
    aarch64-linux-gnu-ld: /tmp/build/tests/workloads/code_with_type.a(code_with_type.code_with_type.d12f4324cb53c560-cgu.0.rcgu.o): Relocations in generic ELF (EM: 62)
    aarch64-linux-gnu-ld: /tmp/build/tests/workloads/code_with_type.a(code_with_type.code_with_type.d12f4324cb53c560-cgu.0.rcgu.o): Relocations in generic ELF (EM: 62)
    aarch64-linux-gnu-ld: /tmp/build/tests/workloads/code_with_type.a: error adding symbols: file in wrong format
    make[5]: *** [/perf/tools/build/Makefile.build:162: /tmp/build/tests/workloads/perf-test-in.o] Error 1
    make[4]: *** [/perf/tools/build/Makefile.build:156: workloads] Error 2
    make[3]: *** [/perf/tools/build/Makefile.build:156: tests] Error 2
    make[2]: *** [Makefile.perf:785: /tmp/build/perf-test-in.o] Error 2
    make[2]: *** Waiting for unfinished jobs....
    make[1]: *** [Makefile.perf:289: sub-make] Error 2
    make: *** [Makefile:76: all] Error 2

Detect required target and pass it via rust_flags to the compiler.

Note that CROSS_COMPILE might be different from what rust compiler
expects, since it may omit the target vendor value, e.g.
"aarch64-linux-gnu" instead of "aarch64-unknown-linux-gnu".

Thus explicitly map supported CROSS_COMPILE values to corresponding Rust
versions, as suggested by Miguel Ojeda.

Tested using arm64 cross-compilation example from [1].

Fixes: 2e05bb52a12d3cdb ("perf test workload: Add code_with_type test workload")
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Dmitrii Dolgov <9erthalion6@gmail.com>
Cc: Levi Zim <i@kxxt.dev>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nsc@kernel.org>
Link: https://perfwiki.github.io/main/arm64-cross-compilation-dockerfile/ [1]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

0 files changed, 0 insertions, 0 deletions