[PATCH] perf tools: fix endian conversion reading event attr from header

David Ahern
2011-07-12T15:19:28Z

The perf_event_attr struct has 2 __u32's at the top and need to
be swapped individually. With this change I was able to analyze
a perf.data collected in a 32-bit PPC VM on an x86 system. I
tested both 32-bit and 64-bit binaries for the Intel analysis
side; both read the PPC perf.data file correctly.

Signed-off-by: David Ahern <dsahern@gmail.com>
---
tools/perf/util/header.c | 9 ++++++++-
1 files changed, 8 insertions(+), 1 deletions(-)

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index afb0849..8044c6f 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -877,9 +877,16 @@ int perf_session__read_header(struct perf_session *session, int fd)
struct perf_evsel *evsel;
off_t tmp;

- if (perf_header__getbuffer64(header, fd, &f_attr, sizeof(f_attr)))
+ if (readn(fd, &f_attr, sizeof(f_attr)) <= 0)
goto out_errno;

+ if (header->needs_swap) {
+ f_attr.attr.type = bswap_32(f_attr.attr.type);
+ f_attr.attr.size = bswap_32(f_attr.attr.size);
+ mem_bswap_64(&f_attr.attr.config,
+ sizeof(struct perf_event_attr) - 8);
+ }
+
tmp = lseek(fd, 0, SEEK_CUR);
evsel = perf_evsel__new(&f_attr.attr, i);

--
1.7.6