Commit c52686f9 authored Jan 29, 2015 by Namhyung Kim Committed by Arnaldo Carvalho de Melo Jan 29, 2015

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>

parent 42aa276f

tools/perf/util/dso.c

+1 −5

Original line number	Diff line number	Diff line
		@@ -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;