Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1211081

[PATCH 13/29] perf tools: Infrastructure for compiling scriptlets when passing '.c' to --event

From Wang Nan <wangnan0@huawei.com>
Newsgroups linux.kernel
Subject [PATCH 13/29] perf tools: Infrastructure for compiling scriptlets when passing '.c' to --event
Date 2015-08-21 12:20 +0200
Message-ID <pZRAu-DT-19@gated-at.bofh.it> (permalink)
References <pZRAt-DT-3@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


This patch provides infrastructure for passing source files to --event
directly using:

 # perf record --event bpf-file.c command

This patch does following works:

 1) Allow passing '.c' file to '--event'. parse_events_load_bpf() is
    expanded to allow caller tell it whether the passed file is source
    file or object.

 2) llvm__compile_bpf() is called to compile the '.c' file, the result
    is saved into memory. Use bpf_object__open_buffer() to load the
    in-memory object.

Introduces a bpf-script-example.c so we can manually test it:

 # perf record --clang-opt "-DLINUX_VERSION_CODE=0x40200" --event ./bpf-script-example.c sleep 1

Note that '--clang-opt' must put before '--event'.

Futher patches will merge it into a testcase so can be tested automatically.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: He Kuang <hekuang@huawei.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kaixu Xia <xiakaixu@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/n/1436445342-1402-20-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/tests/bpf-script-example.c | 44 +++++++++++++++++++++++++++++++++++
 tools/perf/util/bpf-loader.c          | 25 +++++++++++++++-----
 tools/perf/util/bpf-loader.h          | 10 ++++----
 tools/perf/util/parse-events.c        |  6 ++---
 tools/perf/util/parse-events.h        |  3 ++-
 tools/perf/util/parse-events.l        |  3 +++
 tools/perf/util/parse-events.y        | 15 ++++++++++--
 7 files changed, 90 insertions(+), 16 deletions(-)
 create mode 100644 tools/perf/tests/bpf-script-example.c

diff --git a/tools/perf/tests/bpf-script-example.c b/tools/perf/tests/bpf-script-example.c
new file mode 100644
index 0000000..410a70b
--- /dev/null
+++ b/tools/perf/tests/bpf-script-example.c
@@ -0,0 +1,44 @@
+#ifndef LINUX_VERSION_CODE
+# error Need LINUX_VERSION_CODE
+# error Example: for 4.2 kernel, put 'clang-opt="-DLINUX_VERSION_CODE=0x40200" into llvm section of ~/.perfconfig'
+#endif
+#define BPF_ANY 0
+#define BPF_MAP_TYPE_ARRAY 2
+#define BPF_FUNC_map_lookup_elem 1
+#define BPF_FUNC_map_update_elem 2
+
+static void *(*bpf_map_lookup_elem)(void *map, void *key) =
+	(void *) BPF_FUNC_map_lookup_elem;
+static void *(*bpf_map_update_elem)(void *map, void *key, void *value, int flags) =
+	(void *) BPF_FUNC_map_update_elem;
+
+struct bpf_map_def {
+	unsigned int type;
+	unsigned int key_size;
+	unsigned int value_size;
+	unsigned int max_entries;
+};
+
+#define SEC(NAME) __attribute__((section(NAME), used))
+struct bpf_map_def SEC("maps") flip_table = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.key_size = sizeof(int),
+	.value_size = sizeof(int),
+	.max_entries = 1,
+};
+
+SEC("func=sys_epoll_pwait")
+int bpf_func__sys_epoll_pwait(void *ctx)
+{
+	int ind =0;
+	int *flag = bpf_map_lookup_elem(&flip_table, &ind);
+	int new_flag;
+	if (!flag)
+		return 0;
+	/* flip flag and store back */
+	new_flag = !*flag;
+	bpf_map_update_elem(&flip_table, &ind, &new_flag, BPF_ANY);
+	return new_flag;
+}
+char _license[] SEC("license") = "GPL";
+int _version SEC("version") = LINUX_VERSION_CODE;
diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c
index 8e91ad1..5a203ae 100644
--- a/tools/perf/util/bpf-loader.c
+++ b/tools/perf/util/bpf-loader.c
@@ -11,6 +11,7 @@
 #include "bpf-loader.h"
 #include "probe-event.h"
 #include "probe-finder.h"
+#include "llvm-utils.h"
 
 #define DEFINE_PRINT_FN(name, level) \
 static int libbpf_##name(const char *fmt, ...)	\
@@ -152,16 +153,28 @@ sync_bpf_program_pev(struct bpf_program *prog)
 	return 0;
 }
 
-int bpf__prepare_load(const char *filename)
+int bpf__prepare_load(const char *filename, bool source)
 {
 	struct bpf_object *obj;
+	int err;
 
 	if (!libbpf_initialized)
 		libbpf_set_print(libbpf_warning,
 				 libbpf_info,
 				 libbpf_debug);
 
-	obj = bpf_object__open(filename);
+	if (source) {
+		void *obj_buf;
+		size_t obj_buf_sz;
+
+		err = llvm__compile_bpf(filename, &obj_buf, &obj_buf_sz);
+		if (err)
+			return err;
+		obj = bpf_object__open_buffer(obj_buf, obj_buf_sz);
+		free(obj_buf);
+	} else
+		obj = bpf_object__open(filename);
+
 	if (!obj) {
 		pr_debug("bpf: failed to load %s\n", filename);
 		return -EINVAL;
@@ -355,12 +368,12 @@ int bpf__foreach_tev(bpf_prog_iter_callback_t func, void *arg)
 	}\
 	buf[size - 1] = '\0';
 
-int bpf__strerror_prepare_load(const char *filename, int err,
-			       char *buf, size_t size)
+int bpf__strerror_prepare_load(const char *filename, bool source,
+			       int err, char *buf, size_t size)
 {
 	bpf__strerror_head(err, buf, size);
-	bpf__strerror_entry(EINVAL, "%s: BPF object file '%s' is invalid",
-			    emsg, filename)
+	bpf__strerror_entry(EINVAL, "%s: BPF %s file '%s' is invalid",
+			    emsg, source ? "source" : "object", filename);
 	bpf__strerror_end(buf, size);
 	return 0;
 }
diff --git a/tools/perf/util/bpf-loader.h b/tools/perf/util/bpf-loader.h
index 34656f8..c55ffde 100644
--- a/tools/perf/util/bpf-loader.h
+++ b/tools/perf/util/bpf-loader.h
@@ -16,9 +16,9 @@ typedef int (*bpf_prog_iter_callback_t)(struct probe_trace_event *tev,
 					int fd, void *arg);
 
 #ifdef HAVE_LIBBPF_SUPPORT
-int bpf__prepare_load(const char *filename);
-int bpf__strerror_prepare_load(const char *filename, int err,
-			       char *buf, size_t size);
+int bpf__prepare_load(const char *filename, bool source);
+int bpf__strerror_prepare_load(const char *filename, bool source,
+			       int err, char *buf, size_t size);
 int bpf__probe(void);
 int bpf__unprobe(void);
 int bpf__strerror_probe(int err, char *buf, size_t size);
@@ -30,7 +30,8 @@ void bpf__clear(void);
 
 int bpf__foreach_tev(bpf_prog_iter_callback_t func, void *arg);
 #else
-static inline int bpf__prepare_load(const char *filename __maybe_unused)
+static inline int bpf__prepare_load(const char *filename __maybe_unused,
+				    bool source __maybe_unused)
 {
 	pr_debug("ERROR: eBPF object loading is disabled during compiling.\n");
 	return -1;
@@ -62,6 +63,7 @@ __bpf_strerror(char *buf, size_t size)
 
 static inline int
 bpf__strerror_prepare_load(const char *filename __maybe_unused,
+			   bool source __maybe_unused,
 			   int err __maybe_unused,
 			   char *buf, size_t size)
 {
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 9eaceb2..cce3e43 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -484,7 +484,7 @@ int parse_events_add_tracepoint(struct list_head *list, int *idx,
 
 int parse_events_load_bpf(struct parse_events_evlist *data,
 			  struct list_head *list __maybe_unused,
-			  char *bpf_file_name)
+			  char *bpf_file_name, bool source)
 {
 	int err;
 	char errbuf[BUFSIZ];
@@ -497,9 +497,9 @@ int parse_events_load_bpf(struct parse_events_evlist *data,
 	 * problem. After that probe events file by file is possible.
 	 * However, probing cost is still need to be considered.
 	 */
-	err = bpf__prepare_load(bpf_file_name);
+	err = bpf__prepare_load(bpf_file_name, source);
 	if (err) {
-		bpf__strerror_prepare_load(bpf_file_name, err,
+		bpf__strerror_prepare_load(bpf_file_name, source, err,
 					   errbuf, sizeof(errbuf));
 		data->error->str = strdup(errbuf);
 		data->error->help = strdup("(add -v to see detail)");
diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index 3652387..728a424 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -121,7 +121,8 @@ int parse_events_add_tracepoint(struct list_head *list, int *idx,
 				char *sys, char *event);
 int parse_events_load_bpf(struct parse_events_evlist *data,
 			  struct list_head *list,
-			  char *bpf_file_name);
+			  char *bpf_file_name,
+			  bool source);
 int parse_events_add_numeric(struct parse_events_evlist *data,
 			     struct list_head *list,
 			     u32 type, u64 config,
diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l
index 22e8f93..8033890 100644
--- a/tools/perf/util/parse-events.l
+++ b/tools/perf/util/parse-events.l
@@ -116,6 +116,7 @@ group		[^,{}/]*[{][^}]*[}][^,{}/]*
 event_pmu	[^,{}/]+[/][^/]*[/][^,{}/]*
 event		[^,{}/]+
 bpf_object	.*\.(o|bpf)
+bpf_source	.*\.c
 
 num_dec		[0-9]+
 num_hex		0x[a-fA-F0-9]+
@@ -161,6 +162,7 @@ modifier_bp	[rwx]{1,3}
 
 {event_pmu}	|
 {bpf_object}	|
+{bpf_source}	|
 {event}		{
 			BEGIN(INITIAL);
 			REWIND(1);
@@ -267,6 +269,7 @@ r{num_raw_hex}		{ return raw(yyscanner); }
 
 {modifier_event}	{ return str(yyscanner, PE_MODIFIER_EVENT); }
 {bpf_object}		{ return str(yyscanner, PE_BPF_OBJECT); }
+{bpf_source}		{ return str(yyscanner, PE_BPF_SOURCE); }
 {name}			{ return pmu_str_check(yyscanner); }
 "/"			{ BEGIN(config); return '/'; }
 -			{ return '-'; }
diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y
index 3ee3a32..90d2458 100644
--- a/tools/perf/util/parse-events.y
+++ b/tools/perf/util/parse-events.y
@@ -42,7 +42,7 @@ static inc_group_count(struct list_head *list,
 %token PE_VALUE PE_VALUE_SYM_HW PE_VALUE_SYM_SW PE_RAW PE_TERM
 %token PE_EVENT_NAME
 %token PE_NAME
-%token PE_BPF_OBJECT
+%token PE_BPF_OBJECT PE_BPF_SOURCE
 %token PE_MODIFIER_EVENT PE_MODIFIER_BP
 %token PE_NAME_CACHE_TYPE PE_NAME_CACHE_OP_RESULT
 %token PE_PREFIX_MEM PE_PREFIX_RAW PE_PREFIX_GROUP
@@ -55,6 +55,7 @@ static inc_group_count(struct list_head *list,
 %type <num> PE_TERM
 %type <str> PE_NAME
 %type <str> PE_BPF_OBJECT
+%type <str> PE_BPF_SOURCE
 %type <str> PE_NAME_CACHE_TYPE
 %type <str> PE_NAME_CACHE_OP_RESULT
 %type <str> PE_MODIFIER_EVENT
@@ -431,7 +432,17 @@ PE_BPF_OBJECT
 	struct list_head *list;
 
 	ALLOC_LIST(list);
-	ABORT_ON(parse_events_load_bpf(data, list, $1));
+	ABORT_ON(parse_events_load_bpf(data, list, $1, false));
+	$$ = list;
+}
+|
+PE_BPF_SOURCE
+{
+	struct parse_events_evlist *data = _data;
+	struct list_head *list;
+
+	ALLOC_LIST(list);
+	ABORT_ON(parse_events_load_bpf(data, list, $1, true));
 	$$ = list;
 }
 
-- 
2.1.0

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

[GIT PULL 00/29] perf tools: filtering events using eBPF programs Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 25/29] perf record: Support custom vmlinux path Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 14/29] perf tests: Enforce LLVM test for BPF test Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 18/29] perf probe: Reset args and nargs for probe_trace_event when failure Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 11/29] perf tools: Suppress probing messages when probing by BPF loading Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 13/29] perf tools: Infrastructure for compiling scriptlets when passing '.c' to --event Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 19/29] perf tools: Move linux/filter.h to tools/include Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 05/29] perf probe: Attach trace_probe_event with perf_probe_event Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 21/29] perf tools: Introduce arch_get_reg_info() for x86 Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 03/29] perf ebpf: Add the libbpf glue Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 10/29] perf tools: Attach eBPF program to perf event Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 01/29] perf probe: Try to use symbol table if searching debug info failed Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
    Re: [PATCH 01/29] perf probe: Try to use symbol table if searching  debug info failed Arnaldo Carvalho de Melo <acme@redhat.com> - 2015-08-21 16:20 +0200
    [tip:perf/core] perf probe:   Try to use symbol table if searching debug info failed tip-bot for Wang Nan <tipbot@zytor.com> - 2015-08-22 09:00 +0200
  [PATCH 16/29] bpf tools: Load a program with different instances using preprocessor Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 07/29] perf bpf: Collect 'struct perf_probe_event' for bpf_program Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 04/29] perf tools: Enable passing bpf object file to --event Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 20/29] perf tools: Add BPF_PROLOGUE config options for further patches Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 24/29] perf tools: Use same BPF program if arguments are identical Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 23/29] perf tools: Generate prologue for BPF programs Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 02/29] perf tools: Make perf depend on libbpf Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 29/29] bpf: Introduce function for outputing data to perf event Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 12/29] perf record: Add clang options for compiling BPF scripts Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 06/29] perf record, bpf: Parse and probe eBPF programs probe points Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 27/29] perf tools: Support attach BPF program on uprobe events Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 17/29] perf tools: Fix probe-event.h include Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 28/29] tools lib traceevent: Support function __get_dynamic_array_len Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
    Re: [PATCH 28/29] tools lib traceevent: Support function  __get_dynamic_array_len Arnaldo Carvalho de Melo <acme@redhat.com> - 2015-08-21 18:10 +0200
  [PATCH 15/29] perf test: Add 'perf test BPF' Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:20 +0200
  [PATCH 08/29] perf record: Load all eBPF object into kernel Wang Nan <wangnan0@huawei.com> - 2015-08-21 12:30 +0200

csiph-web