2017-08-31 06:38:38

by Ravi Bangoria

Subject: [PATCH] perf test powerpc: Fix 'Object code reading' test

'Object code reading' test always fails on powerpc. Two reasons for
the failure are:

1. When elf section is too big (size beyond 'unsigned int' max value).
objdump fails to disassemble from such section. This was fixed with
commit 0f6329bd7fc ("binutils/objdump: Fix disassemble for huge elf
sections") in binutils.

2. When the sample is from hypervisor. Hypervisor symbols can not
be resolved within guest and thus thread__find_addr_map() fails for
such symbols. Fix this by ignoring hypervisor symbols in the test.

Signed-off-by: Ravi Bangoria <[email protected]>
---
tools/perf/tests/code-reading.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/tools/perf/tests/code-reading.c b/tools/perf/tests/code-reading.c
index 761c5a4..8702592 100644
--- a/tools/perf/tests/code-reading.c
+++ b/tools/perf/tests/code-reading.c
@@ -237,6 +237,10 @@ static int read_object_code(u64 addr, size_t len, u8 cpumode,

thread__find_addr_map(thread, cpumode, MAP__FUNCTION, addr, &al);
if (!al.map || !al.map->dso) {
+ /* Hyprevisor addr can not be resolved. */
+ if (cpumode == PERF_RECORD_MISC_HYPERVISOR)
+ return 0;
+
pr_debug("thread__find_addr_map failed\n");
return -1;
}
--
1.8.3.1

2017-08-31 06:55:49

by Adrian Hunter

Subject: Re: [PATCH] perf test powerpc: Fix 'Object code reading' test

On 31/08/17 09:38, Ravi Bangoria wrote:
> 'Object code reading' test always fails on powerpc. Two reasons for
> the failure are:
>
> 1. When elf section is too big (size beyond 'unsigned int' max value).
> objdump fails to disassemble from such section. This was fixed with
> commit 0f6329bd7fc ("binutils/objdump: Fix disassemble for huge elf
> sections") in binutils.
>
> 2. When the sample is from hypervisor. Hypervisor symbols can not
> be resolved within guest and thus thread__find_addr_map() fails for
> such symbols. Fix this by ignoring hypervisor symbols in the test.
>
> Signed-off-by: Ravi Bangoria <[email protected]>
> ---
> tools/perf/tests/code-reading.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/tools/perf/tests/code-reading.c b/tools/perf/tests/code-reading.c
> index 761c5a4..8702592 100644
> --- a/tools/perf/tests/code-reading.c
> +++ b/tools/perf/tests/code-reading.c
> @@ -237,6 +237,10 @@ static int read_object_code(u64 addr, size_t len, u8 cpumode,
>
> thread__find_addr_map(thread, cpumode, MAP__FUNCTION, addr, &al);
> if (!al.map || !al.map->dso) {
> + /* Hyprevisor addr can not be resolved. */

Hyprevisor -> Hypervisor

> + if (cpumode == PERF_RECORD_MISC_HYPERVISOR)

You need a pr_debug() message here e.g.
pr_debug("Hypervisor address can not be resolved - skipping\n");


> + return 0;
> +
> pr_debug("thread__find_addr_map failed\n");
> return -1;
> }
>