[DTrace-devel] [PATCH 3/3] test: adjust tst.pidprobes.sh to account for PIE executables

[Eugene Loh]

Reviewed-by: Eugene Loh <eugene.loh at oracle.com>
though s/reults/results/ in the commit message would be nice.

On 2/9/26 15:43, Kris Van Hees wrote:
> When the test executable is compiled as position independent code,
> the comparison with expected reults fails unless the reported PC
> values are adjusted based on the actual load address.  This is safe
> to do in general, because for non-PIE cases the adjustment will be
> 0.
>
> Signed-off-by: Kris Van Hees <kris.van.hees at oracle.com>
> ---
>   test/unittest/usdt/tst.pidprobes.sh | 9 ++++++---
>   1 file changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/test/unittest/usdt/tst.pidprobes.sh b/test/unittest/usdt/tst.pidprobes.sh
> index 24fbd518..80de5140 100755
> --- a/test/unittest/usdt/tst.pidprobes.sh
> +++ b/test/unittest/usdt/tst.pidprobes.sh
> @@ -1,7 +1,7 @@
>   #!/bin/bash
>   #
>   # Oracle Linux DTrace.
> -# Copyright (c) 2024, 2025, Oracle and/or its affiliates. All rights reserved.
> +# Copyright (c) 2024, 2026, Oracle and/or its affiliates. All rights reserved.
>   # Licensed under the Universal Permissive License v 1.0 as shown at
>   # http://oss.oracle.com/licenses/upl.
>   #
> @@ -119,8 +119,11 @@ fi
>   pcs=`awk '{print strtonum("0x"$1)}' disasm_foo.txt`
>   pc0=`echo $pcs | awk '{print $1}'`
>   
> -# Construct D script:  add a pid$pid::-:$absoff probe for each PC in foo.
> +# Construct D script:  add a pid$pid::-:$pc0 probe to determine base address.
> +printf 'p*d$target::-:%x\n' $pc0 >> pidprobes.d
> +printf '{\n\tbase = uregs[R_PC] - %s;\n}\n' $pc0 >> pidprobes.d
>   
> +# Construct D script:  add a pid$pid::-:$absoff probe for each PC in foo.
>   for pc in $pcs; do
>   	printf 'p*d$target::-:%x,\n' $pc >> pidprobes.d
>   done
> @@ -130,7 +133,7 @@ done
>   cat >> pidprobes.d <<'EOF'
>   p*d$target::foo:
>   {
> -	printf("%d %s:%s:%s:%s %x\n", pid, probeprov, probemod, probefunc, probename, uregs[R_PC]);
> +	printf("%d %s:%s:%s:%s %x\n", pid, probeprov, probemod, probefunc, probename, uregs[R_PC] - base);
>   }
>   EOF
>