From: Adrian Hunter Date: Fri, 14 Oct 2022 17:09:03 +0000 (+0300) Subject: perf test: test_intel_pt.sh: Add jitdump test X-Git-Tag: v6.6.17~6336^2~11 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=973db24079fc6b292e896b3b9c057a0a6c0d8e93;p=platform%2Fkernel%2Flinux-rpi.git perf test: test_intel_pt.sh: Add jitdump test Add a test for decoding self-modifying code using a jitdump file. The test creates a workload that uses self-modifying code and generates its own jitdump file. The result is processed with perf inject --jit and checked for decoding errors. Note the test will fail without patch "perf inject: Fix GEN_ELF_TEXT_OFFSET for jit" applied. Signed-off-by: Adrian Hunter Tested-by: Arnaldo Carvalho de Melo Cc: Ian Rogers Cc: Jiri Olsa Cc: Namhyung Kim Link: https://lore.kernel.org/r/20221014170905.64069-6-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo --- diff --git a/tools/perf/tests/shell/test_intel_pt.sh b/tools/perf/tests/shell/test_intel_pt.sh index 79dde57..e0bf759 100755 --- a/tools/perf/tests/shell/test_intel_pt.sh +++ b/tools/perf/tests/shell/test_intel_pt.sh @@ -22,6 +22,7 @@ outfile="${temp_dir}/test-out.txt" errfile="${temp_dir}/test-err.txt" workload="${temp_dir}/workload" awkscript="${temp_dir}/awkscript" +jitdump_workload="${temp_dir}/jitdump_workload" cleanup() { @@ -50,6 +51,13 @@ perf_record_no_decode() perf record -B -N --no-bpf-event "$@" } +# perf record for testing should not need BPF events +perf_record_no_bpf() +{ + # Options for no BPF events + perf record --no-bpf-event "$@" +} + have_workload=false cat << _end_of_file_ | /usr/bin/cc -o "${workload}" -xc - -pthread && have_workload=true #include @@ -269,6 +277,159 @@ test_per_thread() return 0 } +test_jitdump() +{ + echo "--- Test tracing self-modifying code that uses jitdump ---" + + script_path=$(realpath "$0") + script_dir=$(dirname "$script_path") + jitdump_incl_dir="${script_dir}/../../util" + jitdump_h="${jitdump_incl_dir}/jitdump.h" + + if [ ! -e "${jitdump_h}" ] ; then + echo "SKIP: Include file jitdump.h not found" + return 2 + fi + + if [ -z "${have_jitdump_workload}" ] ; then + have_jitdump_workload=false + # Create a workload that uses self-modifying code and generates its own jitdump file + cat <<- "_end_of_file_" | /usr/bin/cc -o "${jitdump_workload}" -I "${jitdump_incl_dir}" -xc - -pthread && have_jitdump_workload=true + #define _GNU_SOURCE + #include + #include + #include + #include + #include + #include + #include + + #include "jitdump.h" + + #define CHK_BYTE 0x5a + + static inline uint64_t rdtsc(void) + { + unsigned int low, high; + + asm volatile("rdtsc" : "=a" (low), "=d" (high)); + + return low | ((uint64_t)high) << 32; + } + + static FILE *open_jitdump(void) + { + struct jitheader header = { + .magic = JITHEADER_MAGIC, + .version = JITHEADER_VERSION, + .total_size = sizeof(header), + .pid = getpid(), + .timestamp = rdtsc(), + .flags = JITDUMP_FLAGS_ARCH_TIMESTAMP, + }; + char filename[256]; + FILE *f; + void *m; + + snprintf(filename, sizeof(filename), "jit-%d.dump", getpid()); + f = fopen(filename, "w+"); + if (!f) + goto err; + /* Create an MMAP event for the jitdump file. That is how perf tool finds it. */ + m = mmap(0, 4096, PROT_READ | PROT_EXEC, MAP_PRIVATE, fileno(f), 0); + if (m == MAP_FAILED) + goto err_close; + munmap(m, 4096); + if (fwrite(&header,sizeof(header),1,f) != 1) + goto err_close; + return f; + + err_close: + fclose(f); + err: + return NULL; + } + + static int write_jitdump(FILE *f, void *addr, const uint8_t *dat, size_t sz, uint64_t *idx) + { + struct jr_code_load rec = { + .p.id = JIT_CODE_LOAD, + .p.total_size = sizeof(rec) + sz, + .p.timestamp = rdtsc(), + .pid = getpid(), + .tid = gettid(), + .vma = (unsigned long)addr, + .code_addr = (unsigned long)addr, + .code_size = sz, + .code_index = ++*idx, + }; + + if (fwrite(&rec,sizeof(rec),1,f) != 1 || + fwrite(dat, sz, 1, f) != 1) + return -1; + return 0; + } + + static void close_jitdump(FILE *f) + { + fclose(f); + } + + int main() + { + /* Get a memory page to store executable code */ + void *addr = mmap(0, 4096, PROT_WRITE | PROT_EXEC, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); + /* Code to execute: mov CHK_BYTE, %eax ; ret */ + uint8_t dat[] = {0xb8, CHK_BYTE, 0x00, 0x00, 0x00, 0xc3}; + FILE *f = open_jitdump(); + uint64_t idx = 0; + int ret = 1; + + if (!f) + return 1; + /* Copy executable code to executable memory page */ + memcpy(addr, dat, sizeof(dat)); + /* Record it in the jitdump file */ + if (write_jitdump(f, addr, dat, sizeof(dat), &idx)) + goto out_close; + /* Call it */ + ret = ((int (*)(void))addr)() - CHK_BYTE; + out_close: + close_jitdump(f); + return ret; + } + _end_of_file_ + fi + + if ! $have_jitdump_workload ; then + echo "SKIP: No jitdump workload" + return 2 + fi + + # Change to temp_dir so jitdump collateral files go there + cd "${temp_dir}" + perf_record_no_bpf -o "${tmpfile}" -e intel_pt//u "${jitdump_workload}" + perf inject -i "${tmpfile}" -o "${perfdatafile}" --jit + decode_br_cnt=$(perf script -i "${perfdatafile}" --itrace=b | wc -l) + # Note that overflow and lost errors are suppressed for the error count + decode_err_cnt=$(perf script -i "${perfdatafile}" --itrace=e-o-l | grep -ci error) + cd - + # Should be thousands of branches + if [ "${decode_br_cnt}" -lt 1000 ] ; then + echo "Decode failed, only ${decode_br_cnt} branches" + return 1 + fi + # Should be no errors + if [ "${decode_err_cnt}" -ne 0 ] ; then + echo "Decode failed, ${decode_err_cnt} errors" + perf script -i "${perfdatafile}" --itrace=e-o-l + return 1 + fi + + echo OK + return 0 +} + count_result() { if [ "$1" -eq 2 ] ; then @@ -286,6 +447,7 @@ ret=0 test_system_wide_side_band || ret=$? ; count_result $ret ; ret=0 test_per_thread "" "" || ret=$? ; count_result $ret ; ret=0 test_per_thread "k" "(incl. kernel) " || ret=$? ; count_result $ret ; ret=0 +test_jitdump || ret=$? ; count_result $ret ; ret=0 cleanup