The trace summary test calls /bin/true and filters for open, read and close events. These events are coming from shared library loads. On a musl system, the loader and libc may point to the same file. true needs only libc, no further shared libraries are loaded at startup. The test fails since no open, read and close events are captured. root@host:~# ldd /bin/true /lib/ld-musl-riscv64.so.1 (0x3fb8882000) libc.so => /lib/ld-musl-riscv64.so.1 (0x3fb8882000) root@host:~# file /lib/ld-musl-riscv64.so.1 /lib/ld-musl-riscv64.so.1: symbolic link to /usr/lib/libc.so root@host:~# strace -f /bin/true execve("/bin/true", ["/bin/true", ...], ... /* 18 vars */) = 1 set_tid_address(0x3fa1f7bf70) = 330 mprotect(0x2ad6b8e000, 12288, PROT_READ) = 0 exit_group(0) = ? +++ exited with 0 +++ Run "cat /dev/null" instead of "true". This creates the required events regardless of the C library and it works for cat from busybox or from coreutils.
Unified · Split
| @@ -14,7 +14,7 @@ OUTPUT=$(mktemp /tmp/perf_trace_test.XXXXX) · 13 unmodified lines | ||
| 14 | 14 | |
| 15 | 15 | test_perf_trace() { |
| 16 | 16 | args=$1 |
| 17 | − workload="true" | |
| 17 | + workload="cat /dev/null" | |
| 18 | 18 | search="^\s*(open|read|close).*[0-9]+%$" |
| 19 | 19 | |
| 20 | 20 | echo "testing: perf trace ${args} -- ${workload}" |