perf tools: Add lzma decompression support for kernel module

In short, Fedora compresses kernel modules now (since version 21) with
lzma compression.

Adding lzma decompress support into the dso.c:compressions array
introduced by Namhyung earlier.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-2glp65kdtbrk0gblmirsjsnt@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
index d5b9e0d..e9925e6 100644 (file)
--- a/tools/perf/Makefile.perf
+++ b/tools/perf/Makefile.perf
@@ -71,6 +71,8 @@ include config/utilities.mak
 #
 # Define NO_LIBBABELTRACE if you do not want libbabeltrace support
 # for CTF data format.
+#
+# Define NO_LZMA if you do not want to support compressed (xz) kernel modules
 
 ifeq ($(srctree),)
 srctree := $(patsubst %/,%,$(dir $(shell pwd)))

diff --git a/tools/perf/config/Makefile b/tools/perf/config/Makefile
index 6d1918a..cd121df 100644 (file)
--- a/tools/perf/config/Makefile
+++ b/tools/perf/config/Makefile
@@ -541,6 +541,17 @@ ifndef NO_ZLIB
   endif
 endif
 
+ifndef NO_LZMA
+  ifeq ($(feature-lzma), 1)
+    CFLAGS += -DHAVE_LZMA_SUPPORT
+    EXTLIBS += -llzma
+    $(call detected,CONFIG_LZMA)
+  else
+    msg := $(warning No liblzma found, disables xz kernel module decompression, please install xz-devel/liblzma-dev);
+    NO_LZMA := 1
+  endif
+endif
+
 ifndef NO_BACKTRACE
   ifeq ($(feature-backtrace), 1)
     CFLAGS += -DHAVE_BACKTRACE_SUPPORT

diff --git a/tools/perf/util/Build b/tools/perf/util/Build
index 972a6e0..797490a 100644 (file)
--- a/tools/perf/util/Build
+++ b/tools/perf/util/Build
@@ -94,6 +94,7 @@ libperf-y += scripting-engines/
 
 libperf-$(CONFIG_PERF_REGS) += perf_regs.o
 libperf-$(CONFIG_ZLIB) += zlib.o
+libperf-$(CONFIG_LZMA) += lzma.o
 
 CFLAGS_config.o   += -DETC_PERFCONFIG="BUILD_STR($(ETC_PERFCONFIG_SQ))"
 CFLAGS_exec_cmd.o += -DPERF_EXEC_PATH="BUILD_STR($(perfexecdir_SQ))" -DPREFIX="BUILD_STR($(prefix_SQ))"

diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c
index 814554d..be36841 100644 (file)
--- a/tools/perf/util/dso.c
+++ b/tools/perf/util/dso.c
@@ -147,6 +147,9 @@ static const struct {
 } compressions[] = {
 #ifdef HAVE_ZLIB_SUPPORT
        { "gz", gzip_decompress_to_file },
+#endif
+#ifdef HAVE_LZMA_SUPPORT
+       { "xz", lzma_decompress_to_file },
 #endif
        { NULL, NULL },
 };

diff --git a/tools/perf/util/lzma.c b/tools/perf/util/lzma.c
new file mode 100644 (file)
index 0000000..95a1acb
--- /dev/null
+++ b/tools/perf/util/lzma.c
@@ -0,0 +1,95 @@
+#include <lzma.h>
+#include <stdio.h>
+#include <linux/compiler.h>
+#include "util.h"
+#include "debug.h"
+
+#define BUFSIZE 8192
+
+static const char *lzma_strerror(lzma_ret ret)
+{
+       switch ((int) ret) {
+       case LZMA_MEM_ERROR:
+               return "Memory allocation failed";
+       case LZMA_OPTIONS_ERROR:
+               return "Unsupported decompressor flags";
+       case LZMA_FORMAT_ERROR:
+               return "The input is not in the .xz format";
+       case LZMA_DATA_ERROR:
+               return "Compressed file is corrupt";
+       case LZMA_BUF_ERROR:
+               return "Compressed file is truncated or otherwise corrupt";
+       default:
+               return "Unknown error, possibly a bug";
+       }
+}
+
+int lzma_decompress_to_file(const char *input, int output_fd)
+{
+       lzma_action action = LZMA_RUN;
+       lzma_stream strm   = LZMA_STREAM_INIT;
+       lzma_ret ret;
+
+       u8 buf_in[BUFSIZE];
+       u8 buf_out[BUFSIZE];
+       FILE *infile;
+
+       infile = fopen(input, "rb");
+       if (!infile) {
+               pr_err("lzma: fopen failed on %s: '%s'\n",
+                      input, strerror(errno));
+               return -1;
+       }
+
+       ret = lzma_stream_decoder(&strm, UINT64_MAX, LZMA_CONCATENATED);
+       if (ret != LZMA_OK) {
+               pr_err("lzma: lzma_stream_decoder failed %s (%d)\n",
+                       lzma_strerror(ret), ret);
+               return -1;
+       }
+
+       strm.next_in   = NULL;
+       strm.avail_in  = 0;
+       strm.next_out  = buf_out;
+       strm.avail_out = sizeof(buf_out);
+
+       while (1) {
+               if (strm.avail_in == 0 && !feof(infile)) {
+                       strm.next_in  = buf_in;
+                       strm.avail_in = fread(buf_in, 1, sizeof(buf_in), infile);
+
+                       if (ferror(infile)) {
+                               pr_err("lzma: read error: %s\n", strerror(errno));
+                               return -1;
+                       }
+
+                       if (feof(infile))
+                               action = LZMA_FINISH;
+               }
+
+               ret = lzma_code(&strm, action);
+
+               if (strm.avail_out == 0 || ret == LZMA_STREAM_END) {
+                       ssize_t write_size = sizeof(buf_out) - strm.avail_out;
+
+                       if (writen(output_fd, buf_out, write_size) != write_size) {
+                               pr_err("lzma: write error: %s\n", strerror(errno));
+                               return -1;
+                       }
+
+                       strm.next_out  = buf_out;
+                       strm.avail_out = sizeof(buf_out);
+               }
+
+               if (ret != LZMA_OK) {
+                       if (ret == LZMA_STREAM_END)
+                               return 0;
+
+                       pr_err("lzma: failed %s\n", lzma_strerror(ret));
+                       return -1;
+               }
+       }
+
+       fclose(infile);
+       return 0;
+}

diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
index fbd598a..1ff23e0 100644 (file)
--- a/tools/perf/util/util.h
+++ b/tools/perf/util/util.h
@@ -329,4 +329,8 @@ bool find_process(const char *name);
 int gzip_decompress_to_file(const char *input, int output_fd);
 #endif
 
+#ifdef HAVE_LZMA_SUPPORT
+int lzma_decompress_to_file(const char *input, int output_fd);
+#endif
+
 #endif /* GIT_COMPAT_UTIL_H */