diff options
author | Namhyung Kim <namhyung@kernel.org> | 2015-01-29 17:02:01 -0300 |
---|---|---|
committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2015-01-29 17:02:01 -0300 |
commit | c52686f9f888d23ca72f1309e86af8e91d075697 (patch) | |
tree | 7098b1f13486d538e522191c577c632d3c6cb37e | |
parent | 42aa276f40730211383e9a9923416f1fb9841d68 (diff) |
perf symbols: Convert lseek + read to pread
When dso_cache__read() is called, it reads data from the given offset
using lseek + normal read syscall. It can be combined to a single pread
syscall.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1422518843-25818-40-git-send-email-namhyung@kernel.org
[ Fixed it up when cherry picking it from the multi threaded patchkit ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
-rw-r--r-- | tools/perf/util/dso.c | 6 |
1 files changed, 1 insertions, 5 deletions
diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c index 45be944d450..c2f7d3b9096 100644 --- a/tools/perf/util/dso.c +++ b/tools/perf/util/dso.c @@ -532,12 +532,8 @@ dso_cache__read(struct dso *dso, u64 offset, u8 *data, ssize_t size) break; cache_offset = offset & DSO__DATA_CACHE_MASK; - ret = -EINVAL; - if (-1 == lseek(dso->data.fd, cache_offset, SEEK_SET)) - break; - - ret = read(dso->data.fd, cache->data, DSO__DATA_CACHE_SIZE); + ret = pread(dso->data.fd, cache->data, DSO__DATA_CACHE_SIZE, cache_offset); if (ret <= 0) break; |