[PATCH 2/9] perf/jit: enable jitdump support without dwarf

[Stephane Eranian]

From: Maciej Debski <maci...@google.com>

This patch modifies the build dependencies on the jitdump
support in perf. As it stands jitdump was wrongfully made dependent
100% on using DWARF. However, the dwarf dependency, only exist if
generating the source line table in genelf_debug.c. The rest of the
support does not need DWARF.

This patch removes the dependency on DWARF for the entire jitdump
support. It keeps it only for the genelf_debug.c support.

Signed-off-by: Maciej Debski <maci...@google.com>
Reviewed-by: Stephane Eranian <eran...@google.com>
---
 tools/perf/Makefile.config | 2 --
 tools/perf/util/Build      | 2 +-
 tools/perf/util/genelf.c   | 9 +++++++--
 tools/perf/util/genelf.h   | 2 ++
 4 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
index 72edf83d76b7..8cfc310d4358 100644
--- a/tools/perf/Makefile.config
+++ b/tools/perf/Makefile.config
@@ -366,10 +366,8 @@ ifndef NO_SDT
 endif
 
 ifdef PERF_HAVE_JITDUMP
-  ifndef NO_DWARF
     $(call detected,CONFIG_JITDUMP)
     CFLAGS += -DHAVE_JITDUMP
-  endif
 endif
 
 ifeq ($(ARCH),powerpc)
diff --git a/tools/perf/util/Build b/tools/perf/util/Build
index eb60e613d795..1dc67efad634 100644
--- a/tools/perf/util/Build
+++ b/tools/perf/util/Build
@@ -120,7 +120,7 @@ libperf-y += demangle-rust.o
 ifdef CONFIG_JITDUMP
 libperf-$(CONFIG_LIBELF) += jitdump.o
 libperf-$(CONFIG_LIBELF) += genelf.o
-libperf-$(CONFIG_LIBELF) += genelf_debug.o
+libperf-$(CONFIG_DWARF) += genelf_debug.o
 endif
 
 CFLAGS_config.o   += -DETC_PERFCONFIG="BUILD_STR($(ETC_PERFCONFIG_SQ))"
diff --git a/tools/perf/util/genelf.c b/tools/perf/util/genelf.c
index c1ef805c6a8f..14a73acc549c 100644
--- a/tools/perf/util/genelf.c
+++ b/tools/perf/util/genelf.c
@@ -19,7 +19,9 @@
 #include <limits.h>
 #include <fcntl.h>
 #include <err.h>
+#ifdef HAVE_DWARF_SUPPORT
 #include <dwarf.h>
+#endif
 
 #include "perf.h"
 #include "genelf.h"
@@ -157,7 +159,7 @@ gen_build_id(struct buildid_note *note, unsigned long 
load_addr, const void *cod
 int
 jit_write_elf(int fd, uint64_t load_addr, const char *sym,
              const void *code, int csize,
-             void *debug, int nr_debug_entries)
+             void *debug __maybe_unused, int nr_debug_entries __maybe_unused)
 {
        Elf *e;
        Elf_Data *d;
@@ -386,11 +388,14 @@ jit_write_elf(int fd, uint64_t load_addr, const char *sym,
        shdr->sh_size = sizeof(bnote);
        shdr->sh_entsize = 0;
 
+#ifdef HAVE_DWARF_SUPPORT
        if (debug && nr_debug_entries) {
                retval = jit_add_debug_info(e, load_addr, debug, 
nr_debug_entries);
                if (retval)
                        goto error;
-       } else {
+       } else
+#endif
+       {
                if (elf_update(e, ELF_C_WRITE) < 0) {
                        warnx("elf_update 4 failed");
                        goto error;
diff --git a/tools/perf/util/genelf.h b/tools/perf/util/genelf.h
index 2fbeb59c4bdd..5c933ac71451 100644
--- a/tools/perf/util/genelf.h
+++ b/tools/perf/util/genelf.h
@@ -4,8 +4,10 @@
 /* genelf.c */
 int jit_write_elf(int fd, uint64_t code_addr, const char *sym,
                  const void *code, int csize, void *debug, int 
nr_debug_entries);
+#ifdef HAVE_DWARF_SUPPORT
 /* genelf_debug.c */
 int jit_add_debug_info(Elf *e, uint64_t code_addr, void *debug, int 
nr_debug_entries);
+#endif
 
 #if   defined(__arm__)
 #define GEN_ELF_ARCH   EM_ARM
-- 
1.9.1