Commit 8b42b7e5 authored by Jiri Olsa's avatar Jiri Olsa Committed by Arnaldo Carvalho de Melo
Browse files

perf tools: Add is_compressed callback to compressions array 



Add is_compressed callback to the compressions array, that returns 0 if
the file is compressed or != 0 if not.

The new callback is used to recognize the situation when we have a
'compressed' object, like:

  /lib/modules/.../drivers/net/ethernet/intel/igb/igb.ko.xz

but we need to read its debug data from debuginfo files, which might not
be compressed, like:

  /root/.debug/.build-id/d6/...c4b301f/debug

So even for a 'compressed' object we read debug data from a plain
uncompressed object. To keep this transparent, we detect this in
decompress_kmodule() and return the file descriptor to the uncompressed
file.

Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180817094813.15086-11-jolsa@kernel.org


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent c9a8a613

tools/perf/util/compress.h

+2 −0
Original line number Diff line number Diff line
@@ -4,10 +4,12 @@ 


#ifdef HAVE_ZLIB_SUPPORT

int gzip_decompress_to_file(const char *input, int output_fd);

bool gzip_is_compressed(const char *input);

#endif



#ifdef HAVE_LZMA_SUPPORT

int lzma_decompress_to_file(const char *input, int output_fd);

bool lzma_is_compressed(const char *input);

#endif



#endif /* PERF_COMPRESS_H */

tools/perf/util/dso.c

+20 −3
Original line number Diff line number Diff line
@@ -196,15 +196,16 @@ enum { 
static const struct {

	const char *fmt;

	int (*decompress)(const char *input, int output);

	bool (*is_compressed)(const char *input);

} compressions[] = {

	[COMP_ID__NONE] = { .fmt = NULL, },

#ifdef HAVE_ZLIB_SUPPORT

	{ "gz", gzip_decompress_to_file },

	{ "gz", gzip_decompress_to_file, gzip_is_compressed },

#endif

#ifdef HAVE_LZMA_SUPPORT

	{ "xz", lzma_decompress_to_file },

	{ "xz", lzma_decompress_to_file, lzma_is_compressed },

#endif

	{ NULL, NULL },

	{ NULL, NULL, NULL },

};



static int is_supported_compression(const char *ext)
@@ -262,6 +263,22 @@ static int decompress_kmodule(struct dso *dso, const char *name, 
	if (dso->comp == COMP_ID__NONE)

		return -1;



	/*

	 * We have proper compression id for DSO and yet the file

	 * behind the 'name' can still be plain uncompressed object.

	 *

	 * The reason is behind the logic we open the DSO object files,

	 * when we try all possible 'debug' objects until we find the

	 * data. So even if the DSO is represented by 'krava.xz' module,

	 * we can end up here opening ~/.debug/....23432432/debug' file

	 * which is not compressed.

	 *

	 * To keep this transparent, we detect this and return the file

	 * descriptor to the uncompressed file.

	 */

	if (!compressions[dso->comp].is_compressed(name))

		return open(name, O_RDONLY);



	fd = mkstemp(tmpbuf);

	if (fd < 0) {

		dso->load_errno = errno;

tools/perf/util/lzma.c

+5 −0
Original line number Diff line number Diff line
@@ -99,3 +99,8 @@ err_fclose: 
	fclose(infile);

	return err;

}



bool lzma_is_compressed(const char *input __maybe_unused)

{

	return true;

}

tools/perf/util/zlib.c

+6 −0
Original line number Diff line number Diff line
@@ -5,6 +5,7 @@ 
#include <sys/stat.h>

#include <sys/mman.h>

#include <zlib.h>

#include <linux/compiler.h>



#include "util/compress.h"

#include "util/util.h"
@@ -79,3 +80,8 @@ out_close: 


	return ret == Z_STREAM_END ? 0 : -1;

}



bool gzip_is_compressed(const char *input __maybe_unused)

{

	return true;

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE