[tip:perf/core] perf llvm: Extract helpers in llvm-utils.c
From: tip-bot for Wang Nan
Date: Tue Dec 06 2016 - 03:22:14 EST
Commit-ID: 2bd42de0e196f89994cbae1990d2c7c5a9b6a529
Gitweb: http://git.kernel.org/tip/2bd42de0e196f89994cbae1990d2c7c5a9b6a529
Author: Wang Nan <wangnan0@xxxxxxxxxx>
AuthorDate: Sat, 26 Nov 2016 07:03:30 +0000
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Mon, 5 Dec 2016 15:51:42 -0300
perf llvm: Extract helpers in llvm-utils.c
The following commits will use builtin clang to compile BPF scripts.
llvm__get_kbuild_opts() and llvm__get_nr_cpus() are extracted to help
building '-DKERNEL_VERSION_CODE' and '-D__NR_CPUS__' macros.
Doing object dumping in bpf loader, so further builtin clang compiling
needn't consider it.
Signed-off-by: Wang Nan <wangnan0@xxxxxxxxxx>
Cc: Alexei Starovoitov <ast@xxxxxx>
Cc: He Kuang <hekuang@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Joe Stringer <joe@xxxxxxx>
Cc: Zefan Li <lizefan@xxxxxxxxxx>
Cc: pi3orama@xxxxxxx
Link: http://lkml.kernel.org/r/20161126070354.141764-7-wangnan0@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/util/bpf-loader.c | 4 +++
tools/perf/util/llvm-utils.c | 76 +++++++++++++++++++++++++++++++++-----------
tools/perf/util/llvm-utils.h | 6 ++++
3 files changed, 68 insertions(+), 18 deletions(-)
diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c
index a5fd275..cf16b941 100644
--- a/tools/perf/util/bpf-loader.c
+++ b/tools/perf/util/bpf-loader.c
@@ -90,6 +90,10 @@ struct bpf_object *bpf__prepare_load(const char *filename, bool source)
if (err)
return ERR_PTR(-BPF_LOADER_ERRNO__COMPILE);
obj = bpf_object__open_buffer(obj_buf, obj_buf_sz, filename);
+
+ if (!IS_ERR(obj) && llvm_param.dump_obj)
+ llvm__dump_obj(filename, obj_buf, obj_buf_sz);
+
free(obj_buf);
} else
obj = bpf_object__open(filename);
diff --git a/tools/perf/util/llvm-utils.c b/tools/perf/util/llvm-utils.c
index 27b6f303..b23ff44 100644
--- a/tools/perf/util/llvm-utils.c
+++ b/tools/perf/util/llvm-utils.c
@@ -7,6 +7,7 @@
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
+#include <linux/err.h>
#include "debug.h"
#include "llvm-utils.h"
#include "config.h"
@@ -282,9 +283,10 @@ static const char *kinc_fetch_script =
"rm -rf $TMPDIR\n"
"exit $RET\n";
-static inline void
-get_kbuild_opts(char **kbuild_dir, char **kbuild_include_opts)
+void llvm__get_kbuild_opts(char **kbuild_dir, char **kbuild_include_opts)
{
+ static char *saved_kbuild_dir;
+ static char *saved_kbuild_include_opts;
int err;
if (!kbuild_dir || !kbuild_include_opts)
@@ -293,10 +295,28 @@ get_kbuild_opts(char **kbuild_dir, char **kbuild_include_opts)
*kbuild_dir = NULL;
*kbuild_include_opts = NULL;
+ if (saved_kbuild_dir && saved_kbuild_include_opts &&
+ !IS_ERR(saved_kbuild_dir) && !IS_ERR(saved_kbuild_include_opts)) {
+ *kbuild_dir = strdup(saved_kbuild_dir);
+ *kbuild_include_opts = strdup(saved_kbuild_include_opts);
+
+ if (*kbuild_dir && *kbuild_include_opts)
+ return;
+
+ zfree(kbuild_dir);
+ zfree(kbuild_include_opts);
+ /*
+ * Don't fall through: it may breaks saved_kbuild_dir and
+ * saved_kbuild_include_opts if detect them again when
+ * memory is low.
+ */
+ return;
+ }
+
if (llvm_param.kbuild_dir && !llvm_param.kbuild_dir[0]) {
pr_debug("[llvm.kbuild-dir] is set to \"\" deliberately.\n");
pr_debug("Skip kbuild options detection.\n");
- return;
+ goto errout;
}
err = detect_kbuild_dir(kbuild_dir);
@@ -306,7 +326,7 @@ get_kbuild_opts(char **kbuild_dir, char **kbuild_include_opts)
"Hint:\tSet correct kbuild directory using 'kbuild-dir' option in [llvm]\n"
" \tsection of ~/.perfconfig or set it to \"\" to suppress kbuild\n"
" \tdetection.\n\n");
- return;
+ goto errout;
}
pr_debug("Kernel build dir is set to %s\n", *kbuild_dir);
@@ -325,14 +345,43 @@ get_kbuild_opts(char **kbuild_dir, char **kbuild_include_opts)
free(*kbuild_dir);
*kbuild_dir = NULL;
- return;
+ goto errout;
}
pr_debug("include option is set to %s\n", *kbuild_include_opts);
+
+ saved_kbuild_dir = strdup(*kbuild_dir);
+ saved_kbuild_include_opts = strdup(*kbuild_include_opts);
+
+ if (!saved_kbuild_dir || !saved_kbuild_include_opts) {
+ zfree(&saved_kbuild_dir);
+ zfree(&saved_kbuild_include_opts);
+ }
+ return;
+errout:
+ saved_kbuild_dir = ERR_PTR(-EINVAL);
+ saved_kbuild_include_opts = ERR_PTR(-EINVAL);
}
-static void
-dump_obj(const char *path, void *obj_buf, size_t size)
+int llvm__get_nr_cpus(void)
+{
+ static int nr_cpus_avail = 0;
+ char serr[STRERR_BUFSIZE];
+
+ if (nr_cpus_avail > 0)
+ return nr_cpus_avail;
+
+ nr_cpus_avail = sysconf(_SC_NPROCESSORS_CONF);
+ if (nr_cpus_avail <= 0) {
+ pr_err(
+"WARNING:\tunable to get available CPUs in this system: %s\n"
+" \tUse 128 instead.\n", str_error_r(errno, serr, sizeof(serr)));
+ nr_cpus_avail = 128;
+ }
+ return nr_cpus_avail;
+}
+
+void llvm__dump_obj(const char *path, void *obj_buf, size_t size)
{
char *obj_path = strdup(path);
FILE *fp;
@@ -406,15 +455,9 @@ int llvm__compile_bpf(const char *path, void **p_obj_buf,
* This is an optional work. Even it fail we can continue our
* work. Needn't to check error return.
*/
- get_kbuild_opts(&kbuild_dir, &kbuild_include_opts);
+ llvm__get_kbuild_opts(&kbuild_dir, &kbuild_include_opts);
- nr_cpus_avail = sysconf(_SC_NPROCESSORS_CONF);
- if (nr_cpus_avail <= 0) {
- pr_err(
-"WARNING:\tunable to get available CPUs in this system: %s\n"
-" \tUse 128 instead.\n", str_error_r(errno, serr, sizeof(serr)));
- nr_cpus_avail = 128;
- }
+ nr_cpus_avail = llvm__get_nr_cpus();
snprintf(nr_cpus_avail_str, sizeof(nr_cpus_avail_str), "%d",
nr_cpus_avail);
@@ -453,9 +496,6 @@ int llvm__compile_bpf(const char *path, void **p_obj_buf,
free(kbuild_dir);
free(kbuild_include_opts);
- if (llvm_param.dump_obj)
- dump_obj(path, obj_buf, obj_buf_sz);
-
if (!p_obj_buf)
free(obj_buf);
else
diff --git a/tools/perf/util/llvm-utils.h b/tools/perf/util/llvm-utils.h
index 9f501ce..c87a2a9 100644
--- a/tools/perf/util/llvm-utils.h
+++ b/tools/perf/util/llvm-utils.h
@@ -50,4 +50,10 @@ int llvm__compile_bpf(const char *path, void **p_obj_buf, size_t *p_obj_buf_sz);
/* This function is for test__llvm() use only */
int llvm__search_clang(void);
+
+/* Following functions are reused by builtin clang support */
+void llvm__get_kbuild_opts(char **kbuild_dir, char **kbuild_include_opts);
+int llvm__get_nr_cpus(void);
+
+void llvm__dump_obj(const char *path, void *obj_buf, size_t size);
#endif