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* [PATCH 0/9] perf annotation of BPF programs
@ 2019-02-09  1:16 Song Liu
  2019-02-09  1:16 ` [PATCH 1/9] perf, bpf: consider events with attr.bpf_event as side-band events Song Liu
                   ` (5 more replies)
  0 siblings, 6 replies; 13+ messages in thread
From: Song Liu @ 2019-02-09  1:16 UTC (permalink / raw)
  To: netdev, linux-kernel; +Cc: ast, daniel, kernel-team, peterz, acme, Song Liu

This series enables annotation of BPF programs in perf.

perf tool gathers information via sys_bpf and (optionally) stores them in
perf.data as headers.

Patch 1/9 fixes a minor issue in kernel;
Patch 2/9 to 4/9 introduce new helper functions and use them in perf and
     bpftool;
Patch 5/9 and 6/9 saves information of bpf program in perf_env;
Patch 7/9 adds --bpf-event options to perf-top;
Patch 8/9 enables annotation of bpf programs based on information gathered
     in 5/9 and 6/9;
Patch 9/9 handles information of short living BPF program that are loaded
     during perf-record or perf-top.

Commands tested during developments are perf-top, perf-record, perf-report,
and perf-annotate.

===================== Note on patch dependency  ========================
This set has dependency in both bpf-next tree and tip/perf/core. Current
version is developed on bpf-next tree with the following commits
cherry-picked from tip/perf/core:

(from 1/10 to 10/10)
commit 76193a94522f ("perf, bpf: Introduce PERF_RECORD_KSYMBOL")
commit d764ac646491 ("tools headers uapi: Sync tools/include/uapi/linux/perf_event.h")
commit 6ee52e2a3fe4 ("perf, bpf: Introduce PERF_RECORD_BPF_EVENT")
commit df063c83aa2c ("tools headers uapi: Sync tools/include/uapi/linux/perf_event.h")
commit 9aa0bfa370b2 ("perf tools: Handle PERF_RECORD_KSYMBOL")
commit 45178a928a4b ("perf tools: Handle PERF_RECORD_BPF_EVENT")
commit 7b612e291a5a ("perf tools: Synthesize PERF_RECORD_* for loaded BPF programs")
commit a40b95bcd30c ("perf top: Synthesize BPF events for pre-existing loaded BPF programs")
commit 6934058d9fb6 ("bpf: Add module name [bpf] to ksymbols for bpf programs")
commit 811184fb6977 ("perf bpf: Fix synthesized PERF_RECORD_KSYMBOL/BPF_EVENT")
========================================================================

Song Liu (9):
  perf, bpf: consider events with attr.bpf_event as side-band events
  bpf: libbpf: introduce bpf_program__get_prog_info_linear()
  bpf: bpftool: use bpf_program__get_prog_info_linear() in
    prog.c:do_dump()
  perf, bpf: synthesize bpf events with
    bpf_program__get_prog_info_linear()
  perf, bpf: save bpf_prog_info in a rbtree in perf_env
  perf, bpf: save btf in a rbtree in perf_env
  perf-top: add option --bpf-event
  perf, bpf: enable annotation of bpf program
  perf, bpf: save information about short living bpf programs

 kernel/events/core.c        |   3 +-
 tools/bpf/bpftool/prog.c    | 266 ++++++---------------------
 tools/lib/bpf/libbpf.c      | 251 ++++++++++++++++++++++++++
 tools/lib/bpf/libbpf.h      |  63 +++++++
 tools/lib/bpf/libbpf.map    |   3 +
 tools/perf/Makefile.config  |   2 +-
 tools/perf/builtin-record.c |  15 +-
 tools/perf/builtin-top.c    |  15 +-
 tools/perf/util/annotate.c  | 149 ++++++++++++++-
 tools/perf/util/bpf-event.c | 351 +++++++++++++++++++++++++++---------
 tools/perf/util/bpf-event.h |  48 ++++-
 tools/perf/util/dso.c       |   1 +
 tools/perf/util/dso.h       |  33 ++--
 tools/perf/util/env.c       | 148 +++++++++++++++
 tools/perf/util/env.h       |  12 ++
 tools/perf/util/evlist.c    |  20 ++
 tools/perf/util/evlist.h    |   2 +
 tools/perf/util/header.c    | 231 +++++++++++++++++++++++-
 tools/perf/util/header.h    |   2 +
 tools/perf/util/symbol.c    |   1 +
 20 files changed, 1304 insertions(+), 312 deletions(-)

--
2.17.1

^ permalink raw reply	[flat|nested] 13+ messages in thread

* [PATCH 1/9] perf, bpf: consider events with attr.bpf_event as side-band events
  2019-02-09  1:16 [PATCH 0/9] perf annotation of BPF programs Song Liu
@ 2019-02-09  1:16 ` Song Liu
  2019-02-09  1:16 ` [PATCH 2/9] bpf: libbpf: introduce bpf_program__get_prog_info_linear() Song Liu
                   ` (4 subsequent siblings)
  5 siblings, 0 replies; 13+ messages in thread
From: Song Liu @ 2019-02-09  1:16 UTC (permalink / raw)
  To: netdev, linux-kernel; +Cc: ast, daniel, kernel-team, peterz, acme, Song Liu

Events with bpf_event should be considered as side-band event, as they
carry information about BPF programs.

Fixes: 6ee52e2a3fe4 ("perf, bpf: Introduce PERF_RECORD_BPF_EVENT")
Signed-off-by: Song Liu <songliubraving@fb.com>
---
 kernel/events/core.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 0a8dab322111..9403bdda5f8c 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -4238,7 +4238,8 @@ static bool is_sb_event(struct perf_event *event)
 	if (attr->mmap || attr->mmap_data || attr->mmap2 ||
 	    attr->comm || attr->comm_exec ||
 	    attr->task || attr->ksymbol ||
-	    attr->context_switch)
+	    attr->context_switch ||
+	    attr->bpf_event)
 		return true;
 	return false;
 }
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 13+ messages in thread

* [PATCH 2/9] bpf: libbpf: introduce bpf_program__get_prog_info_linear()
  2019-02-09  1:16 [PATCH 0/9] perf annotation of BPF programs Song Liu
  2019-02-09  1:16 ` [PATCH 1/9] perf, bpf: consider events with attr.bpf_event as side-band events Song Liu
@ 2019-02-09  1:16 ` Song Liu
  2019-02-09  1:16 ` [PATCH 3/9] bpf: bpftool: use bpf_program__get_prog_info_linear() in prog.c:do_dump() Song Liu
                   ` (3 subsequent siblings)
  5 siblings, 0 replies; 13+ messages in thread
From: Song Liu @ 2019-02-09  1:16 UTC (permalink / raw)
  To: netdev, linux-kernel; +Cc: ast, daniel, kernel-team, peterz, acme, Song Liu

Currently, bpf_prog_info includes 9 arrays. The user has the option to
fetch any combination of these arrays. However, this requires a lot of
handling of these arrays. This work becomes more tricky when we need to
store bpf_prog_info to a file, because these arrays are allocated
independently.

This patch introduces struct bpf_prog_info_linear, which stores arrays
of bpf_prog_info in continues memory. Helper functions are introduced
to unify the work to get different information of bpf_prog_info.
Specifically, bpf_program__get_prog_info_linear() allows the user to
select which arrays to fetch, and handles details for the user.

Plesae see the comments before enum bpf_prog_info_array for more details
and examples.

Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Song Liu <songliubraving@fb.com>
---
 tools/lib/bpf/libbpf.c   | 251 +++++++++++++++++++++++++++++++++++++++
 tools/lib/bpf/libbpf.h   |  63 ++++++++++
 tools/lib/bpf/libbpf.map |   3 +
 3 files changed, 317 insertions(+)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index e3c39edfb9d3..1f808c555747 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -113,6 +113,11 @@ void libbpf_print(enum libbpf_print_level level, const char *format, ...)
 # define LIBBPF_ELF_C_READ_MMAP ELF_C_READ
 #endif
 
+static inline __u64 ptr_to_u64(const void *ptr)
+{
+	return (__u64) (unsigned long) ptr;
+}
+
 struct bpf_capabilities {
 	/* v4.14: kernel support for program & map names. */
 	__u32 name:1;
@@ -2979,3 +2984,249 @@ bpf_perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size,
 	ring_buffer_write_tail(header, data_tail);
 	return ret;
 }
+
+struct bpf_prog_info_array_desc {
+	int	array_offset;	/* e.g. offset of jited_prog_insns */
+	int	count_offset;	/* e.g. offset of jited_prog_len */
+	int	size_offset;	/* > 0: offset of rec size,
+				 * < 0: fix size of -size_offset
+				 */
+};
+
+static struct bpf_prog_info_array_desc bpf_prog_info_array_desc[] = {
+	[BPF_PROG_INFO_JITED_INSNS] = {
+		offsetof(struct bpf_prog_info, jited_prog_insns),
+		offsetof(struct bpf_prog_info, jited_prog_len),
+		-1,
+	},
+	[BPF_PROG_INFO_XLATED_INSNS] = {
+		offsetof(struct bpf_prog_info, xlated_prog_insns),
+		offsetof(struct bpf_prog_info, xlated_prog_len),
+		-1,
+	},
+	[BPF_PROG_INFO_MAP_IDS] = {
+		offsetof(struct bpf_prog_info, map_ids),
+		offsetof(struct bpf_prog_info, nr_map_ids),
+		-(int)sizeof(__u32),
+	},
+	[BPF_PROG_INFO_JITED_KSYMS] = {
+		offsetof(struct bpf_prog_info, jited_ksyms),
+		offsetof(struct bpf_prog_info, nr_jited_ksyms),
+		-(int)sizeof(__u64),
+	},
+	[BPF_PROG_INFO_JITED_FUNC_LENS] = {
+		offsetof(struct bpf_prog_info, jited_func_lens),
+		offsetof(struct bpf_prog_info, nr_jited_func_lens),
+		-(int)sizeof(__u32),
+	},
+	[BPF_PROG_INFO_FUNC_INFO] = {
+		offsetof(struct bpf_prog_info, func_info),
+		offsetof(struct bpf_prog_info, nr_func_info),
+		offsetof(struct bpf_prog_info, func_info_rec_size),
+	},
+	[BPF_PROG_INFO_LINE_INFO] = {
+		offsetof(struct bpf_prog_info, line_info),
+		offsetof(struct bpf_prog_info, nr_line_info),
+		offsetof(struct bpf_prog_info, line_info_rec_size),
+	},
+	[BPF_PROG_INFO_JITED_LINE_INFO] = {
+		offsetof(struct bpf_prog_info, jited_line_info),
+		offsetof(struct bpf_prog_info, nr_jited_line_info),
+		offsetof(struct bpf_prog_info, jited_line_info_rec_size),
+	},
+	[BPF_PROG_INFO_PROG_TAGS] = {
+		offsetof(struct bpf_prog_info, prog_tags),
+		offsetof(struct bpf_prog_info, nr_prog_tags),
+		-(int)sizeof(__u8) * BPF_TAG_SIZE,
+	},
+
+};
+
+static __u32 bpf_prog_info_read_offset_u32(struct bpf_prog_info *info, int offset)
+{
+	__u32 *array = (__u32 *)info;
+
+	if (offset >= 0)
+		return array[offset / sizeof(__u32)];
+	return -(int)offset;
+}
+
+static __u64 bpf_prog_info_read_offset_u64(struct bpf_prog_info *info, int offset)
+{
+	__u64 *array = (__u64 *)info;
+
+	if (offset >= 0)
+		return array[offset / sizeof(__u64)];
+	return -(int)offset;
+}
+
+static void bpf_prog_info_set_offset_u32(struct bpf_prog_info *info, int offset,
+					 __u32 val)
+{
+	__u32 *array = (__u32 *)info;
+
+	if (offset >= 0)
+		array[offset / sizeof(__u32)] = val;
+}
+
+static void bpf_prog_info_set_offset_u64(struct bpf_prog_info *info, int offset,
+					 __u64 val)
+{
+	__u64 *array = (__u64 *)info;
+
+	if (offset >= 0)
+		array[offset / sizeof(__u64)] = val;
+}
+
+struct bpf_prog_info_linear *
+bpf_program__get_prog_info_linear(int fd, __u64 arrays)
+{
+	struct bpf_prog_info_linear *info_linear;
+	struct bpf_prog_info info = {};
+	__u32 info_len = sizeof(info);
+	__u32 data_len = 0;
+	int i, err;
+	void *ptr;
+
+	if (arrays >> BPF_PROG_INFO_LAST_ARRAY)
+		return ERR_PTR(-EINVAL);
+
+	/* step 1: get array dimensions */
+	err = bpf_obj_get_info_by_fd(fd, &info, &info_len);
+	if (err) {
+		pr_debug("can't get prog info: %s", strerror(errno));
+		return ERR_PTR(-EFAULT);
+	}
+
+	/* step 2: calculate total size of all arrays */
+	for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) {
+		bool include_array = (arrays & (1UL << i)) > 0;
+		struct bpf_prog_info_array_desc *desc;
+		__u32 count, size;
+
+		desc = bpf_prog_info_array_desc + i;
+
+		/* kernel is too old to support this field */
+		if (info_len < desc->array_offset + sizeof(__u32) ||
+		    info_len < desc->count_offset + sizeof(__u32) ||
+		    (desc->size_offset > 0 && info_len < desc->size_offset))
+			include_array = false;
+
+		if (!include_array) {
+			arrays &= ~(1UL << i);	/* clear the bit */
+			continue;
+		}
+
+		count = bpf_prog_info_read_offset_u32(&info, desc->count_offset);
+		size = bpf_prog_info_read_offset_u32(&info, desc->size_offset);
+
+		data_len += count * size;
+	}
+
+	/* step 3: allocate continuous memory */
+	data_len = roundup(data_len, sizeof(__u64));
+	info_linear = malloc(sizeof(struct bpf_prog_info_linear) + data_len);
+	if (!info_linear)
+		return ERR_PTR(-ENOMEM);
+
+	/* step 4: fill data to info_linear->info */
+	info_linear->arrays = arrays;
+	memset(&info_linear->info, 0, sizeof(info));
+	ptr = info_linear->data;
+
+	for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) {
+		struct bpf_prog_info_array_desc *desc;
+		__u32 count, size;
+
+		if ((arrays & (1UL << i)) == 0)
+			continue;
+
+		desc = bpf_prog_info_array_desc + i;
+		count = bpf_prog_info_read_offset_u32(&info, desc->count_offset);
+		size = bpf_prog_info_read_offset_u32(&info, desc->size_offset);
+		bpf_prog_info_set_offset_u32(&info_linear->info,
+					     desc->count_offset, count);
+		bpf_prog_info_set_offset_u32(&info_linear->info,
+					     desc->size_offset, size);
+		bpf_prog_info_set_offset_u64(&info_linear->info,
+					     desc->array_offset,
+					     ptr_to_u64(ptr));
+		ptr += count * size;
+	}
+
+	/* step 5: call syscall again to get required arrays */
+	err = bpf_obj_get_info_by_fd(fd, &info_linear->info, &info_len);
+	if (err) {
+		pr_debug("can't get prog info: %s", strerror(errno));
+		free(info_linear);
+		return ERR_PTR(-EFAULT);
+	}
+
+	/* step 6: verify the data */
+	for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) {
+		struct bpf_prog_info_array_desc *desc;
+		__u32 v1, v2;
+
+		if ((arrays & (1UL << i)) == 0)
+			continue;
+
+		desc = bpf_prog_info_array_desc + i;
+		v1 = bpf_prog_info_read_offset_u32(&info, desc->count_offset);
+		v2 = bpf_prog_info_read_offset_u32(&info_linear->info,
+						   desc->count_offset);
+		if (v1 != v2)
+			pr_warning("%s: mismatch in element count\n", __func__);
+
+		v1 = bpf_prog_info_read_offset_u32(&info, desc->size_offset);
+		v2 = bpf_prog_info_read_offset_u32(&info_linear->info,
+						   desc->size_offset);
+		if (v1 != v2)
+			pr_warning("%s: mismatch in rec size\n", __func__);
+	}
+
+	/* step 7: update info_len and data_len */
+	info_linear->info_len = sizeof(struct bpf_prog_info);
+	info_linear->data_len = data_len;
+
+	return info_linear;
+}
+
+void bpf_program__bpil_addr_to_offs(struct bpf_prog_info_linear *info_linear)
+{
+	int i;
+
+	for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) {
+		struct bpf_prog_info_array_desc *desc;
+		__u64 addr, offs;
+
+		if ((info_linear->arrays & (1UL << i)) == 0)
+			continue;
+
+		desc = bpf_prog_info_array_desc + i;
+		addr = bpf_prog_info_read_offset_u64(&info_linear->info,
+						     desc->array_offset);
+		offs = addr - ptr_to_u64(info_linear->data);
+		bpf_prog_info_set_offset_u64(&info_linear->info,
+					     desc->array_offset, offs);
+	}
+}
+
+void bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear)
+{
+	int i;
+
+	for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) {
+		struct bpf_prog_info_array_desc *desc;
+		__u64 addr, offs;
+
+		if ((info_linear->arrays & (1UL << i)) == 0)
+			continue;
+
+		desc = bpf_prog_info_array_desc + i;
+		offs = bpf_prog_info_read_offset_u64(&info_linear->info,
+						     desc->array_offset);
+		addr = offs + ptr_to_u64(info_linear->data);
+		bpf_prog_info_set_offset_u64(&info_linear->info,
+					     desc->array_offset, addr);
+	}
+}
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index 69a7c25eaccc..4d357c26fbd2 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -372,6 +372,69 @@ LIBBPF_API bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex);
 LIBBPF_API bool bpf_probe_helper(enum bpf_func_id id,
 				 enum bpf_prog_type prog_type, __u32 ifindex);
 
+/*
+ * Get bpf_prog_info in continuous memory
+ *
+ * struct bpf_prog_info has multiple arrays. The user has option to choose
+ * arrays to fetch from kernel. The following APIs provide uniform way to
+ * fetch these data. All arrays in bpf_prog_info are stored in singile
+ * continuous memory region. This makes it easy to store the info in a
+ * file.
+ *
+ * Before writing bpf_prog_info_linear to files, it is necessary to
+ * translate pointers bpf_prog_info to offsets. Helper functions
+ * bpf_program__bpil_addr_to_offs() and bpf_program__bpil_offs_to_addr()
+ * are introduced to switch between pointers and offsets.
+ *
+ * Examples:
+ *   # To fetch map_ids and prog_tags:
+ *   __u64 arrays = (1UL << BPF_PROG_INFO_MAP_IDS) |
+ *           (1UL << BPF_PROG_INFO_PROG_TAGS);
+ *   struct bpf_prog_info_linear *info_linear =
+ *           bpf_program__get_prog_info_linear(fd, arrays);
+ *
+ *   # To save data in file
+ *   bpf_program__bpil_addr_to_offs(info_linear);
+ *   write(f, info_linear, sizeof(*info_linear) + info_linear->data_len);
+ *
+ *   # To read data from file
+ *   read(f, info_linear, <proper_size>);
+ *   bpf_program__bpil_offs_to_addr(info_linear);
+ */
+enum bpf_prog_info_array {
+	BPF_PROG_INFO_FIRST_ARRAY = 0,
+	BPF_PROG_INFO_JITED_INSNS = 0,
+	BPF_PROG_INFO_XLATED_INSNS,
+	BPF_PROG_INFO_MAP_IDS,
+	BPF_PROG_INFO_JITED_KSYMS,
+	BPF_PROG_INFO_JITED_FUNC_LENS,
+	BPF_PROG_INFO_FUNC_INFO,
+	BPF_PROG_INFO_LINE_INFO,
+	BPF_PROG_INFO_JITED_LINE_INFO,
+	BPF_PROG_INFO_PROG_TAGS,
+	BPF_PROG_INFO_LAST_ARRAY,
+};
+
+struct bpf_prog_info_linear {
+	/* size of struct bpf_prog_info, when the tool is compiled */
+	__u32			info_len;
+	/* total bytes allocated for data, round up to 8 bytes */
+	__u32			data_len;
+	/* which arrays are included in data */
+	__u64			arrays;
+	struct bpf_prog_info	info;
+	__u8			data[];
+};
+
+LIBBPF_API struct bpf_prog_info_linear *
+bpf_program__get_prog_info_linear(int fd, __u64 arrays);
+
+LIBBPF_API void
+bpf_program__bpil_addr_to_offs(struct bpf_prog_info_linear *info_linear);
+
+LIBBPF_API void
+bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear);
+
 #ifdef __cplusplus
 } /* extern "C" */
 #endif
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index 5fc8222209f8..5f2fceec6ea7 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -145,4 +145,7 @@ LIBBPF_0.0.2 {
 		btf_ext__new;
 		btf_ext__reloc_func_info;
 		btf_ext__reloc_line_info;
+		bpf_program__get_prog_info_linear;
+		bpf_program__bpil_addr_to_offs;
+		bpf_program__bpil_offs_to_addr;
 } LIBBPF_0.0.1;
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 13+ messages in thread

* [PATCH 3/9] bpf: bpftool: use bpf_program__get_prog_info_linear() in prog.c:do_dump()
  2019-02-09  1:16 [PATCH 0/9] perf annotation of BPF programs Song Liu
  2019-02-09  1:16 ` [PATCH 1/9] perf, bpf: consider events with attr.bpf_event as side-band events Song Liu
  2019-02-09  1:16 ` [PATCH 2/9] bpf: libbpf: introduce bpf_program__get_prog_info_linear() Song Liu
@ 2019-02-09  1:16 ` Song Liu
  2019-02-09  1:17 ` [PATCH 4/9] perf, bpf: synthesize bpf events with bpf_program__get_prog_info_linear() Song Liu
                   ` (2 subsequent siblings)
  5 siblings, 0 replies; 13+ messages in thread
From: Song Liu @ 2019-02-09  1:16 UTC (permalink / raw)
  To: netdev, linux-kernel; +Cc: ast, daniel, kernel-team, peterz, acme, Song Liu

This patches uses bpf_program__get_prog_info_linear() to simplify the
logic in prog.c do_dump().

Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Song Liu <songliubraving@fb.com>
---
 tools/bpf/bpftool/prog.c | 266 +++++++++------------------------------
 1 file changed, 59 insertions(+), 207 deletions(-)

diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
index 0640e9bc0ada..206b820df7c2 100644
--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c
@@ -393,41 +393,31 @@ static int do_show(int argc, char **argv)
 
 static int do_dump(int argc, char **argv)
 {
-	unsigned int finfo_rec_size, linfo_rec_size, jited_linfo_rec_size;
-	void *func_info = NULL, *linfo = NULL, *jited_linfo = NULL;
-	unsigned int nr_finfo, nr_linfo = 0, nr_jited_linfo = 0;
+	struct bpf_prog_info_linear *info_linear;
 	struct bpf_prog_linfo *prog_linfo = NULL;
-	unsigned long *func_ksyms = NULL;
-	struct bpf_prog_info info = {};
-	unsigned int *func_lens = NULL;
+	enum {DUMP_JITED, DUMP_XLATED} mode;
 	const char *disasm_opt = NULL;
-	unsigned int nr_func_ksyms;
-	unsigned int nr_func_lens;
+	struct bpf_prog_info *info;
 	struct dump_data dd = {};
-	__u32 len = sizeof(info);
+	void *func_info = NULL;
 	struct btf *btf = NULL;
-	unsigned int buf_size;
 	char *filepath = NULL;
 	bool opcodes = false;
 	bool visual = false;
 	char func_sig[1024];
 	unsigned char *buf;
 	bool linum = false;
-	__u32 *member_len;
-	__u64 *member_ptr;
+	__u32 member_len;
+	__u64 arrays;
 	ssize_t n;
-	int err;
 	int fd;
 
 	if (is_prefix(*argv, "jited")) {
 		if (disasm_init())
 			return -1;
-
-		member_len = &info.jited_prog_len;
-		member_ptr = &info.jited_prog_insns;
+		mode = DUMP_JITED;
 	} else if (is_prefix(*argv, "xlated")) {
-		member_len = &info.xlated_prog_len;
-		member_ptr = &info.xlated_prog_insns;
+		mode = DUMP_XLATED;
 	} else {
 		p_err("expected 'xlated' or 'jited', got: %s", *argv);
 		return -1;
@@ -466,175 +456,50 @@ static int do_dump(int argc, char **argv)
 		return -1;
 	}
 
-	err = bpf_obj_get_info_by_fd(fd, &info, &len);
-	if (err) {
-		p_err("can't get prog info: %s", strerror(errno));
-		return -1;
-	}
-
-	if (!*member_len) {
-		p_info("no instructions returned");
-		close(fd);
-		return 0;
-	}
+	if (mode == DUMP_JITED)
+		arrays = 1UL << BPF_PROG_INFO_JITED_INSNS;
+	else
+		arrays = 1UL << BPF_PROG_INFO_XLATED_INSNS;
 
-	buf_size = *member_len;
+	arrays |= 1UL << BPF_PROG_INFO_JITED_KSYMS;
+	arrays |= 1UL << BPF_PROG_INFO_JITED_FUNC_LENS;
+	arrays |= 1UL << BPF_PROG_INFO_FUNC_INFO;
+	arrays |= 1UL << BPF_PROG_INFO_LINE_INFO;
+	arrays |= 1UL << BPF_PROG_INFO_JITED_LINE_INFO;
 
-	buf = malloc(buf_size);
-	if (!buf) {
-		p_err("mem alloc failed");
-		close(fd);
+	info_linear = bpf_program__get_prog_info_linear(fd, arrays);
+	close(fd);
+	if (IS_ERR_OR_NULL(info_linear)) {
+		p_err("can't get prog info: %s", strerror(errno));
 		return -1;
 	}
 
-	nr_func_ksyms = info.nr_jited_ksyms;
-	if (nr_func_ksyms) {
-		func_ksyms = malloc(nr_func_ksyms * sizeof(__u64));
-		if (!func_ksyms) {
-			p_err("mem alloc failed");
-			close(fd);
-			goto err_free;
-		}
-	}
-
-	nr_func_lens = info.nr_jited_func_lens;
-	if (nr_func_lens) {
-		func_lens = malloc(nr_func_lens * sizeof(__u32));
-		if (!func_lens) {
-			p_err("mem alloc failed");
-			close(fd);
+	info = &info_linear->info;
+	if (mode == DUMP_JITED) {
+		if (info->jited_prog_len == 0) {
+			p_info("no instructions returned");
 			goto err_free;
 		}
-	}
-
-	nr_finfo = info.nr_func_info;
-	finfo_rec_size = info.func_info_rec_size;
-	if (nr_finfo && finfo_rec_size) {
-		func_info = malloc(nr_finfo * finfo_rec_size);
-		if (!func_info) {
-			p_err("mem alloc failed");
-			close(fd);
+		buf = (unsigned char *)(info->jited_prog_insns);
+		member_len = info->jited_prog_len;
+	} else {	/* DUMP_XLATED */
+		if (info->xlated_prog_len == 0) {
+			p_err("error retrieving insn dump: kernel.kptr_restrict set?");
 			goto err_free;
 		}
+		buf = (unsigned char *)info->xlated_prog_insns;
+		member_len = info->xlated_prog_len;
 	}
 
-	linfo_rec_size = info.line_info_rec_size;
-	if (info.nr_line_info && linfo_rec_size && info.btf_id) {
-		nr_linfo = info.nr_line_info;
-		linfo = malloc(nr_linfo * linfo_rec_size);
-		if (!linfo) {
-			p_err("mem alloc failed");
-			close(fd);
-			goto err_free;
-		}
-	}
-
-	jited_linfo_rec_size = info.jited_line_info_rec_size;
-	if (info.nr_jited_line_info &&
-	    jited_linfo_rec_size &&
-	    info.nr_jited_ksyms &&
-	    info.nr_jited_func_lens &&
-	    info.btf_id) {
-		nr_jited_linfo = info.nr_jited_line_info;
-		jited_linfo = malloc(nr_jited_linfo * jited_linfo_rec_size);
-		if (!jited_linfo) {
-			p_err("mem alloc failed");
-			close(fd);
-			goto err_free;
-		}
-	}
-
-	memset(&info, 0, sizeof(info));
-
-	*member_ptr = ptr_to_u64(buf);
-	*member_len = buf_size;
-	info.jited_ksyms = ptr_to_u64(func_ksyms);
-	info.nr_jited_ksyms = nr_func_ksyms;
-	info.jited_func_lens = ptr_to_u64(func_lens);
-	info.nr_jited_func_lens = nr_func_lens;
-	info.nr_func_info = nr_finfo;
-	info.func_info_rec_size = finfo_rec_size;
-	info.func_info = ptr_to_u64(func_info);
-	info.nr_line_info = nr_linfo;
-	info.line_info_rec_size = linfo_rec_size;
-	info.line_info = ptr_to_u64(linfo);
-	info.nr_jited_line_info = nr_jited_linfo;
-	info.jited_line_info_rec_size = jited_linfo_rec_size;
-	info.jited_line_info = ptr_to_u64(jited_linfo);
-
-	err = bpf_obj_get_info_by_fd(fd, &info, &len);
-	close(fd);
-	if (err) {
-		p_err("can't get prog info: %s", strerror(errno));
-		goto err_free;
-	}
-
-	if (*member_len > buf_size) {
-		p_err("too many instructions returned");
-		goto err_free;
-	}
-
-	if (info.nr_jited_ksyms > nr_func_ksyms) {
-		p_err("too many addresses returned");
-		goto err_free;
-	}
-
-	if (info.nr_jited_func_lens > nr_func_lens) {
-		p_err("too many values returned");
-		goto err_free;
-	}
-
-	if (info.nr_func_info != nr_finfo) {
-		p_err("incorrect nr_func_info %d vs. expected %d",
-		      info.nr_func_info, nr_finfo);
-		goto err_free;
-	}
-
-	if (info.func_info_rec_size != finfo_rec_size) {
-		p_err("incorrect func_info_rec_size %d vs. expected %d",
-		      info.func_info_rec_size, finfo_rec_size);
-		goto err_free;
-	}
-
-	if (linfo && info.nr_line_info != nr_linfo) {
-		p_err("incorrect nr_line_info %u vs. expected %u",
-		      info.nr_line_info, nr_linfo);
-		goto err_free;
-	}
-
-	if (info.line_info_rec_size != linfo_rec_size) {
-		p_err("incorrect line_info_rec_size %u vs. expected %u",
-		      info.line_info_rec_size, linfo_rec_size);
-		goto err_free;
-	}
-
-	if (jited_linfo && info.nr_jited_line_info != nr_jited_linfo) {
-		p_err("incorrect nr_jited_line_info %u vs. expected %u",
-		      info.nr_jited_line_info, nr_jited_linfo);
-		goto err_free;
-	}
-
-	if (info.jited_line_info_rec_size != jited_linfo_rec_size) {
-		p_err("incorrect jited_line_info_rec_size %u vs. expected %u",
-		      info.jited_line_info_rec_size, jited_linfo_rec_size);
-		goto err_free;
-	}
-
-	if ((member_len == &info.jited_prog_len &&
-	     info.jited_prog_insns == 0) ||
-	    (member_len == &info.xlated_prog_len &&
-	     info.xlated_prog_insns == 0)) {
-		p_err("error retrieving insn dump: kernel.kptr_restrict set?");
-		goto err_free;
-	}
-
-	if (info.btf_id && btf__get_from_id(info.btf_id, &btf)) {
+	if (info->btf_id && btf__get_from_id(info->btf_id, &btf)) {
 		p_err("failed to get btf");
 		goto err_free;
 	}
 
-	if (nr_linfo) {
-		prog_linfo = bpf_prog_linfo__new(&info);
+	func_info = (void *)info->func_info;
+
+	if (info->nr_line_info) {
+		prog_linfo = bpf_prog_linfo__new(info);
 		if (!prog_linfo)
 			p_info("error in processing bpf_line_info.  continue without it.");
 	}
@@ -647,9 +512,9 @@ static int do_dump(int argc, char **argv)
 			goto err_free;
 		}
 
-		n = write(fd, buf, *member_len);
+		n = write(fd, buf, member_len);
 		close(fd);
-		if (n != *member_len) {
+		if (n != member_len) {
 			p_err("error writing output file: %s",
 			      n < 0 ? strerror(errno) : "short write");
 			goto err_free;
@@ -657,19 +522,19 @@ static int do_dump(int argc, char **argv)
 
 		if (json_output)
 			jsonw_null(json_wtr);
-	} else if (member_len == &info.jited_prog_len) {
+	} else if (mode == DUMP_JITED) {
 		const char *name = NULL;
 
-		if (info.ifindex) {
-			name = ifindex_to_bfd_params(info.ifindex,
-						     info.netns_dev,
-						     info.netns_ino,
+		if (info->ifindex) {
+			name = ifindex_to_bfd_params(info->ifindex,
+						     info->netns_dev,
+						     info->netns_ino,
 						     &disasm_opt);
 			if (!name)
 				goto err_free;
 		}
 
-		if (info.nr_jited_func_lens && info.jited_func_lens) {
+		if (info->nr_jited_func_lens && info->jited_func_lens) {
 			struct kernel_sym *sym = NULL;
 			struct bpf_func_info *record;
 			char sym_name[SYM_MAX_NAME];
@@ -677,17 +542,16 @@ static int do_dump(int argc, char **argv)
 			__u64 *ksyms = NULL;
 			__u32 *lens;
 			__u32 i;
-
-			if (info.nr_jited_ksyms) {
+			if (info->nr_jited_ksyms) {
 				kernel_syms_load(&dd);
-				ksyms = (__u64 *) info.jited_ksyms;
+				ksyms = (__u64 *) info->jited_ksyms;
 			}
 
 			if (json_output)
 				jsonw_start_array(json_wtr);
 
-			lens = (__u32 *) info.jited_func_lens;
-			for (i = 0; i < info.nr_jited_func_lens; i++) {
+			lens = (__u32 *) info->jited_func_lens;
+			for (i = 0; i < info->nr_jited_func_lens; i++) {
 				if (ksyms) {
 					sym = kernel_syms_search(&dd, ksyms[i]);
 					if (sym)
@@ -699,7 +563,7 @@ static int do_dump(int argc, char **argv)
 				}
 
 				if (func_info) {
-					record = func_info + i * finfo_rec_size;
+					record = func_info + i * info->func_info_rec_size;
 					btf_dumper_type_only(btf, record->type_id,
 							     func_sig,
 							     sizeof(func_sig));
@@ -736,49 +600,37 @@ static int do_dump(int argc, char **argv)
 			if (json_output)
 				jsonw_end_array(json_wtr);
 		} else {
-			disasm_print_insn(buf, *member_len, opcodes, name,
+			disasm_print_insn(buf, member_len, opcodes, name,
 					  disasm_opt, btf, NULL, 0, 0, false);
 		}
 	} else if (visual) {
 		if (json_output)
 			jsonw_null(json_wtr);
 		else
-			dump_xlated_cfg(buf, *member_len);
+			dump_xlated_cfg(buf, member_len);
 	} else {
 		kernel_syms_load(&dd);
-		dd.nr_jited_ksyms = info.nr_jited_ksyms;
-		dd.jited_ksyms = (__u64 *) info.jited_ksyms;
+		dd.nr_jited_ksyms = info->nr_jited_ksyms;
+		dd.jited_ksyms = (__u64 *) info->jited_ksyms;
 		dd.btf = btf;
 		dd.func_info = func_info;
-		dd.finfo_rec_size = finfo_rec_size;
+		dd.finfo_rec_size = info->func_info_rec_size;
 		dd.prog_linfo = prog_linfo;
 
 		if (json_output)
-			dump_xlated_json(&dd, buf, *member_len, opcodes,
+			dump_xlated_json(&dd, buf, member_len, opcodes,
 					 linum);
 		else
-			dump_xlated_plain(&dd, buf, *member_len, opcodes,
+			dump_xlated_plain(&dd, buf, member_len, opcodes,
 					  linum);
 		kernel_syms_destroy(&dd);
 	}
 
-	free(buf);
-	free(func_ksyms);
-	free(func_lens);
-	free(func_info);
-	free(linfo);
-	free(jited_linfo);
-	bpf_prog_linfo__free(prog_linfo);
+	free(info_linear);
 	return 0;
 
 err_free:
-	free(buf);
-	free(func_ksyms);
-	free(func_lens);
-	free(func_info);
-	free(linfo);
-	free(jited_linfo);
-	bpf_prog_linfo__free(prog_linfo);
+	free(info_linear);
 	return -1;
 }
 
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 13+ messages in thread

* [PATCH 4/9] perf, bpf: synthesize bpf events with bpf_program__get_prog_info_linear()
  2019-02-09  1:16 [PATCH 0/9] perf annotation of BPF programs Song Liu
                   ` (2 preceding siblings ...)
  2019-02-09  1:16 ` [PATCH 3/9] bpf: bpftool: use bpf_program__get_prog_info_linear() in prog.c:do_dump() Song Liu
@ 2019-02-09  1:17 ` Song Liu
  2019-02-09  1:17 ` [PATCH 5/9] perf, bpf: save bpf_prog_info in a rbtree in perf_env Song Liu
  2019-02-11 18:54 ` [PATCH 0/9] perf annotation of BPF programs Arnaldo Carvalho de Melo
  5 siblings, 0 replies; 13+ messages in thread
From: Song Liu @ 2019-02-09  1:17 UTC (permalink / raw)
  To: netdev, linux-kernel; +Cc: ast, daniel, kernel-team, peterz, acme, Song Liu

With bpf_program__get_prog_info_linear, we can simplify the logic that
synthesizes bpf events.

This patch doesn't change the behavior of the code.

Signed-off-by: Song Liu <songliubraving@fb.com>
---
 tools/perf/util/bpf-event.c | 118 ++++++++++++------------------------
 1 file changed, 40 insertions(+), 78 deletions(-)

diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c
index 796ef793f4ce..e6dfb95029e5 100644
--- a/tools/perf/util/bpf-event.c
+++ b/tools/perf/util/bpf-event.c
@@ -3,7 +3,9 @@
 #include <stdlib.h>
 #include <bpf/bpf.h>
 #include <bpf/btf.h>
+#include <bpf/libbpf.h>
 #include <linux/btf.h>
+#include <linux/err.h>
 #include "bpf-event.h"
 #include "debug.h"
 #include "symbol.h"
@@ -49,99 +51,62 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_tool *tool,
 {
 	struct ksymbol_event *ksymbol_event = &event->ksymbol_event;
 	struct bpf_event *bpf_event = &event->bpf_event;
-	u32 sub_prog_cnt, i, func_info_rec_size = 0;
-	u8 (*prog_tags)[BPF_TAG_SIZE] = NULL;
-	struct bpf_prog_info info = { .type = 0, };
-	u32 info_len = sizeof(info);
-	void *func_infos = NULL;
-	u64 *prog_addrs = NULL;
+	struct bpf_prog_info_linear *info_linear;
+	struct bpf_prog_info *info;
 	struct btf *btf = NULL;
-	u32 *prog_lens = NULL;
 	bool has_btf = false;
-	char errbuf[512];
+	u32 sub_prog_cnt, i;
 	int err = 0;
+	u64 arrays;
 
-	/* Call bpf_obj_get_info_by_fd() to get sizes of arrays */
-	err = bpf_obj_get_info_by_fd(fd, &info, &info_len);
+	arrays = 1UL << BPF_PROG_INFO_JITED_KSYMS;
+	arrays |= 1UL << BPF_PROG_INFO_JITED_FUNC_LENS;
+	arrays |= 1UL << BPF_PROG_INFO_FUNC_INFO;
+	arrays |= 1UL << BPF_PROG_INFO_PROG_TAGS;
 
-	if (err) {
-		pr_debug("%s: failed to get BPF program info: %s, aborting\n",
-			 __func__, str_error_r(errno, errbuf, sizeof(errbuf)));
+	info_linear = bpf_program__get_prog_info_linear(fd, arrays);
+	if (IS_ERR_OR_NULL(info_linear)) {
+		info_linear = NULL;
+		pr_debug("%s: failed to get BPF program info. aborting\n", __func__);
 		return -1;
 	}
-	if (info_len < offsetof(struct bpf_prog_info, prog_tags)) {
+
+	if (info_linear->info_len < offsetof(struct bpf_prog_info, prog_tags)) {
 		pr_debug("%s: the kernel is too old, aborting\n", __func__);
 		return -2;
 	}
 
+	info = &info_linear->info;
+
 	/* number of ksyms, func_lengths, and tags should match */
-	sub_prog_cnt = info.nr_jited_ksyms;
-	if (sub_prog_cnt != info.nr_prog_tags ||
-	    sub_prog_cnt != info.nr_jited_func_lens)
+	sub_prog_cnt = info->nr_jited_ksyms;
+	if (sub_prog_cnt != info->nr_prog_tags ||
+	    sub_prog_cnt != info->nr_jited_func_lens)
 		return -1;
 
 	/* check BTF func info support */
-	if (info.btf_id && info.nr_func_info && info.func_info_rec_size) {
+	if (info->btf_id && info->nr_func_info && info->func_info_rec_size) {
 		/* btf func info number should be same as sub_prog_cnt */
-		if (sub_prog_cnt != info.nr_func_info) {
+		if (sub_prog_cnt != info->nr_func_info) {
 			pr_debug("%s: mismatch in BPF sub program count and BTF function info count, aborting\n", __func__);
-			return -1;
-		}
-		if (btf__get_from_id(info.btf_id, &btf)) {
-			pr_debug("%s: failed to get BTF of id %u, aborting\n", __func__, info.btf_id);
-			return -1;
+			err = -1;
+			goto out;
 		}
-		func_info_rec_size = info.func_info_rec_size;
-		func_infos = calloc(sub_prog_cnt, func_info_rec_size);
-		if (!func_infos) {
-			pr_debug("%s: failed to allocate memory for func_infos, aborting\n", __func__);
-			return -1;
+		if (btf__get_from_id(info->btf_id, &btf)) {
+			pr_debug("%s: failed to get BTF of id %u, aborting\n", __func__, info->btf_id);
+			err = -1;
+			btf = NULL;
+			goto out;
 		}
 		has_btf = true;
 	}
 
-	/*
-	 * We need address, length, and tag for each sub program.
-	 * Allocate memory and call bpf_obj_get_info_by_fd() again
-	 */
-	prog_addrs = calloc(sub_prog_cnt, sizeof(u64));
-	if (!prog_addrs) {
-		pr_debug("%s: failed to allocate memory for prog_addrs, aborting\n", __func__);
-		goto out;
-	}
-	prog_lens = calloc(sub_prog_cnt, sizeof(u32));
-	if (!prog_lens) {
-		pr_debug("%s: failed to allocate memory for prog_lens, aborting\n", __func__);
-		goto out;
-	}
-	prog_tags = calloc(sub_prog_cnt, BPF_TAG_SIZE);
-	if (!prog_tags) {
-		pr_debug("%s: failed to allocate memory for prog_tags, aborting\n", __func__);
-		goto out;
-	}
-
-	memset(&info, 0, sizeof(info));
-	info.nr_jited_ksyms = sub_prog_cnt;
-	info.nr_jited_func_lens = sub_prog_cnt;
-	info.nr_prog_tags = sub_prog_cnt;
-	info.jited_ksyms = ptr_to_u64(prog_addrs);
-	info.jited_func_lens = ptr_to_u64(prog_lens);
-	info.prog_tags = ptr_to_u64(prog_tags);
-	info_len = sizeof(info);
-	if (has_btf) {
-		info.nr_func_info = sub_prog_cnt;
-		info.func_info_rec_size = func_info_rec_size;
-		info.func_info = ptr_to_u64(func_infos);
-	}
-
-	err = bpf_obj_get_info_by_fd(fd, &info, &info_len);
-	if (err) {
-		pr_debug("%s: failed to get BPF program info, aborting\n", __func__);
-		goto out;
-	}
-
 	/* Synthesize PERF_RECORD_KSYMBOL */
 	for (i = 0; i < sub_prog_cnt; i++) {
+		u8 (*prog_tags)[BPF_TAG_SIZE] = (void *)(info->prog_tags);
+		__u32 *prog_lens = (__u32 *)(info->jited_func_lens);
+		__u64 *prog_addrs = (__u64 *)(info->jited_ksyms);
+		void *func_infos = (void *)(info->func_info);
 		const struct bpf_func_info *finfo;
 		const char *short_name = NULL;
 		const struct btf_type *t;
@@ -163,13 +128,13 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_tool *tool,
 					 KSYM_NAME_LEN - name_len,
 					 prog_tags[i], BPF_TAG_SIZE);
 		if (has_btf) {
-			finfo = func_infos + i * info.func_info_rec_size;
+			finfo = func_infos + i * info->func_info_rec_size;
 			t = btf__type_by_id(btf, finfo->type_id);
 			short_name = btf__name_by_offset(btf, t->name_off);
 		} else if (i == 0 && sub_prog_cnt == 1) {
 			/* no subprog */
-			if (info.name[0])
-				short_name = info.name;
+			if (info->name[0])
+				short_name = info->name;
 		} else
 			short_name = "F";
 		if (short_name)
@@ -195,9 +160,9 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_tool *tool,
 			},
 			.type = PERF_BPF_EVENT_PROG_LOAD,
 			.flags = 0,
-			.id = info.id,
+			.id = info->id,
 		};
-		memcpy(bpf_event->tag, prog_tags[i], BPF_TAG_SIZE);
+		memcpy(bpf_event->tag, info->tag, BPF_TAG_SIZE);
 		memset((void *)event + event->header.size, 0, machine->id_hdr_size);
 		event->header.size += machine->id_hdr_size;
 		err = perf_tool__process_synth_event(tool, event,
@@ -205,10 +170,7 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_tool *tool,
 	}
 
 out:
-	free(prog_tags);
-	free(prog_lens);
-	free(prog_addrs);
-	free(func_infos);
+	free(info_linear);
 	free(btf);
 	return err ? -1 : 0;
 }
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 13+ messages in thread

* [PATCH 5/9] perf, bpf: save bpf_prog_info in a rbtree in perf_env
  2019-02-09  1:16 [PATCH 0/9] perf annotation of BPF programs Song Liu
                   ` (3 preceding siblings ...)
  2019-02-09  1:17 ` [PATCH 4/9] perf, bpf: synthesize bpf events with bpf_program__get_prog_info_linear() Song Liu
@ 2019-02-09  1:17 ` Song Liu
  2019-02-14 12:26   ` Jiri Olsa
  2019-02-14 12:33   ` Jiri Olsa
  2019-02-11 18:54 ` [PATCH 0/9] perf annotation of BPF programs Arnaldo Carvalho de Melo
  5 siblings, 2 replies; 13+ messages in thread
From: Song Liu @ 2019-02-09  1:17 UTC (permalink / raw)
  To: netdev, linux-kernel; +Cc: ast, daniel, kernel-team, peterz, acme, Song Liu

bpf_prog_info contains information necessary to annotate bpf programs.
This patch saves bpf_prog_info for bpf programs loaded in the system.

perf-record saves bpf_prog_info information as headers to perf.data.
A new header type HEADER_BPF_PROG_INFO is introduced for this data.

Signed-off-by: Song Liu <songliubraving@fb.com>
---
 tools/perf/builtin-record.c |   2 +-
 tools/perf/builtin-top.c    |   2 +-
 tools/perf/util/bpf-event.c |  39 ++++++++---
 tools/perf/util/bpf-event.h |  15 +++-
 tools/perf/util/env.c       |  83 ++++++++++++++++++++++
 tools/perf/util/env.h       |   9 +++
 tools/perf/util/header.c    | 134 +++++++++++++++++++++++++++++++++++-
 tools/perf/util/header.h    |   1 +
 8 files changed, 271 insertions(+), 14 deletions(-)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 88ea11d57c6f..2355e0a9eda0 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -1083,7 +1083,7 @@ static int record__synthesize(struct record *rec, bool tail)
 		return err;
 	}
 
-	err = perf_event__synthesize_bpf_events(tool, process_synthesized_event,
+	err = perf_event__synthesize_bpf_events(session, process_synthesized_event,
 						machine, opts);
 	if (err < 0)
 		pr_warning("Couldn't synthesize bpf events.\n");
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 5a486d4de56e..27d8d42e0a4d 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -1216,7 +1216,7 @@ static int __cmd_top(struct perf_top *top)
 
 	init_process_thread(top);
 
-	ret = perf_event__synthesize_bpf_events(&top->tool, perf_event__process,
+	ret = perf_event__synthesize_bpf_events(top->session, perf_event__process,
 						&top->session->machines.host,
 						&top->record_opts);
 	if (ret < 0)
diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c
index e6dfb95029e5..ead599bc4f4e 100644
--- a/tools/perf/util/bpf-event.c
+++ b/tools/perf/util/bpf-event.c
@@ -1,15 +1,13 @@
 // SPDX-License-Identifier: GPL-2.0
 #include <errno.h>
 #include <stdlib.h>
-#include <bpf/bpf.h>
-#include <bpf/btf.h>
-#include <bpf/libbpf.h>
-#include <linux/btf.h>
 #include <linux/err.h>
 #include "bpf-event.h"
 #include "debug.h"
 #include "symbol.h"
 #include "machine.h"
+#include "env.h"
+#include "session.h"
 
 #define ptr_to_u64(ptr)    ((__u64)(unsigned long)(ptr))
 
@@ -42,7 +40,7 @@ int machine__process_bpf_event(struct machine *machine __maybe_unused,
  *   -1 for failures;
  *   -2 for lack of kernel support.
  */
-static int perf_event__synthesize_one_bpf_prog(struct perf_tool *tool,
+static int perf_event__synthesize_one_bpf_prog(struct perf_session *session,
 					       perf_event__handler_t process,
 					       struct machine *machine,
 					       int fd,
@@ -52,17 +50,29 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_tool *tool,
 	struct ksymbol_event *ksymbol_event = &event->ksymbol_event;
 	struct bpf_event *bpf_event = &event->bpf_event;
 	struct bpf_prog_info_linear *info_linear;
+	struct perf_tool *tool = session->tool;
+	struct bpf_prog_info_node *info_node;
 	struct bpf_prog_info *info;
 	struct btf *btf = NULL;
 	bool has_btf = false;
+	struct perf_env *env;
 	u32 sub_prog_cnt, i;
 	int err = 0;
 	u64 arrays;
 
+	/*
+	 * for perf-record and perf-report use header.env;
+	 * otherwise, use global perf_env.
+	 */
+	env = session->data ? &session->header.env : &perf_env;
+
 	arrays = 1UL << BPF_PROG_INFO_JITED_KSYMS;
 	arrays |= 1UL << BPF_PROG_INFO_JITED_FUNC_LENS;
 	arrays |= 1UL << BPF_PROG_INFO_FUNC_INFO;
 	arrays |= 1UL << BPF_PROG_INFO_PROG_TAGS;
+	arrays |= 1UL << BPF_PROG_INFO_JITED_INSNS;
+	arrays |= 1UL << BPF_PROG_INFO_LINE_INFO;
+	arrays |= 1UL << BPF_PROG_INFO_JITED_LINE_INFO;
 
 	info_linear = bpf_program__get_prog_info_linear(fd, arrays);
 	if (IS_ERR_OR_NULL(info_linear)) {
@@ -151,8 +161,8 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_tool *tool,
 						     machine, process);
 	}
 
-	/* Synthesize PERF_RECORD_BPF_EVENT */
 	if (opts->bpf_event) {
+		/* Synthesize PERF_RECORD_BPF_EVENT */
 		*bpf_event = (struct bpf_event){
 			.header = {
 				.type = PERF_RECORD_BPF_EVENT,
@@ -165,6 +175,19 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_tool *tool,
 		memcpy(bpf_event->tag, info->tag, BPF_TAG_SIZE);
 		memset((void *)event + event->header.size, 0, machine->id_hdr_size);
 		event->header.size += machine->id_hdr_size;
+
+		/* save bpf_prog_info to env */
+		info_node = malloc(sizeof(struct bpf_prog_info_node));
+		if (info_node) {
+			info_node->info_linear = info_linear;
+			perf_env__insert_bpf_prog_info(env, info_node);
+			info_linear = NULL;
+		}
+
+		/*
+		 * process after saving bpf_prog_info to env, so that
+		 * required information is ready for look up
+		 */
 		err = perf_tool__process_synth_event(tool, event,
 						     machine, process);
 	}
@@ -175,7 +198,7 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_tool *tool,
 	return err ? -1 : 0;
 }
 
-int perf_event__synthesize_bpf_events(struct perf_tool *tool,
+int perf_event__synthesize_bpf_events(struct perf_session *session,
 				      perf_event__handler_t process,
 				      struct machine *machine,
 				      struct record_opts *opts)
@@ -209,7 +232,7 @@ int perf_event__synthesize_bpf_events(struct perf_tool *tool,
 			continue;
 		}
 
-		err = perf_event__synthesize_one_bpf_prog(tool, process,
+		err = perf_event__synthesize_one_bpf_prog(session, process,
 							  machine, fd,
 							  event, opts);
 		close(fd);
diff --git a/tools/perf/util/bpf-event.h b/tools/perf/util/bpf-event.h
index 7890067e1a37..11e6730b6105 100644
--- a/tools/perf/util/bpf-event.h
+++ b/tools/perf/util/bpf-event.h
@@ -3,19 +3,28 @@
 #define __PERF_BPF_EVENT_H
 
 #include <linux/compiler.h>
+#include <bpf/bpf.h>
+#include <bpf/btf.h>
+#include <bpf/libbpf.h>
+#include <linux/btf.h>
+#include <linux/rbtree.h>
 #include "event.h"
 
 struct machine;
 union perf_event;
 struct perf_sample;
-struct perf_tool;
 struct record_opts;
 
+struct bpf_prog_info_node {
+	struct bpf_prog_info_linear	*info_linear;
+	struct rb_node			rb_node;
+};
+
 #ifdef HAVE_LIBBPF_SUPPORT
 int machine__process_bpf_event(struct machine *machine, union perf_event *event,
 			       struct perf_sample *sample);
 
-int perf_event__synthesize_bpf_events(struct perf_tool *tool,
+int perf_event__synthesize_bpf_events(struct perf_session *session,
 				      perf_event__handler_t process,
 				      struct machine *machine,
 				      struct record_opts *opts);
@@ -27,7 +36,7 @@ static inline int machine__process_bpf_event(struct machine *machine __maybe_unu
 	return 0;
 }
 
-static inline int perf_event__synthesize_bpf_events(struct perf_tool *tool __maybe_unused,
+static inline int perf_event__synthesize_bpf_events(struct perf_session *session __maybe_unused,
 						    perf_event__handler_t process __maybe_unused,
 						    struct machine *machine __maybe_unused,
 						    struct record_opts *opts __maybe_unused)
diff --git a/tools/perf/util/env.c b/tools/perf/util/env.c
index 4c23779e271a..665b6fe3c7b2 100644
--- a/tools/perf/util/env.c
+++ b/tools/perf/util/env.c
@@ -8,10 +8,86 @@
 
 struct perf_env perf_env;
 
+void perf_env__insert_bpf_prog_info(struct perf_env *env,
+				    struct bpf_prog_info_node *info_node)
+{
+	__u32 prog_id = info_node->info_linear->info.id;
+	struct bpf_prog_info_node *node;
+	struct rb_node *parent = NULL;
+	struct rb_node **p;
+
+	down_write(&env->bpf_info_lock);
+	p = &env->bpf_prog_infos.rb_node;
+
+	while (*p != NULL) {
+		parent = *p;
+		node = rb_entry(parent, struct bpf_prog_info_node, rb_node);
+		if (prog_id < node->info_linear->info.id) {
+			p = &(*p)->rb_left;
+		} else if (prog_id > node->info_linear->info.id) {
+			p = &(*p)->rb_right;
+		} else {
+			pr_debug("duplicated bpf prog info %u\n", prog_id);
+			up_write(&env->bpf_info_lock);
+			return;
+		}
+	}
+
+	rb_link_node(&info_node->rb_node, parent, p);
+	rb_insert_color(&info_node->rb_node, &env->bpf_prog_infos);
+	up_write(&env->bpf_info_lock);
+}
+
+struct bpf_prog_info_node *perf_env__find_bpf_prog_info(struct perf_env *env,
+							__u32 prog_id)
+{
+	struct bpf_prog_info_node *node = NULL;
+	struct rb_node *n;
+
+	down_read(&env->bpf_info_lock);
+	n = env->bpf_prog_infos.rb_node;
+
+	while (n) {
+		node = rb_entry(n, struct bpf_prog_info_node, rb_node);
+		if (prog_id < node->info_linear->info.id)
+			n = n->rb_left;
+		else if (prog_id > node->info_linear->info.id)
+			n = n->rb_right;
+		else
+			break;
+	}
+
+	up_read(&env->bpf_info_lock);
+	return node;
+}
+
+/* purge data in bpf_prog_infos tree */
+static void purge_bpf_info(struct perf_env *env)
+{
+	struct rb_root *root;
+	struct rb_node *next;
+
+	down_write(&env->bpf_info_lock);
+
+	root = &env->bpf_prog_infos;
+	next = rb_first(root);
+
+	while (next) {
+		struct bpf_prog_info_node *node;
+
+		node = rb_entry(next, struct bpf_prog_info_node, rb_node);
+		next = rb_next(&node->rb_node);
+		rb_erase_init(&node->rb_node, root);
+		free(node);
+	}
+	up_write(&env->bpf_info_lock);
+}
+
 void perf_env__exit(struct perf_env *env)
 {
 	int i;
 
+	purge_bpf_info(env);
 	zfree(&env->hostname);
 	zfree(&env->os_release);
 	zfree(&env->version);
@@ -38,6 +114,12 @@ void perf_env__exit(struct perf_env *env)
 	zfree(&env->memory_nodes);
 }
 
+static void init_bpf_rb_trees(struct perf_env *env)
+{
+	env->bpf_prog_infos = RB_ROOT;
+	init_rwsem(&env->bpf_info_lock);
+}
+
 int perf_env__set_cmdline(struct perf_env *env, int argc, const char *argv[])
 {
 	int i;
@@ -59,6 +141,7 @@ int perf_env__set_cmdline(struct perf_env *env, int argc, const char *argv[])
 
 	env->nr_cmdline = argc;
 
+	init_bpf_rb_trees(env);
 	return 0;
 out_free:
 	zfree(&env->cmdline_argv);
diff --git a/tools/perf/util/env.h b/tools/perf/util/env.h
index d01b8355f4ca..5894a177b7cf 100644
--- a/tools/perf/util/env.h
+++ b/tools/perf/util/env.h
@@ -3,7 +3,10 @@
 #define __PERF_ENV_H
 
 #include <linux/types.h>
+#include <linux/rbtree.h>
 #include "cpumap.h"
+#include "rwsem.h"
+#include "bpf-event.h"
 
 struct cpu_topology_map {
 	int	socket_id;
@@ -64,6 +67,8 @@ struct perf_env {
 	struct memory_node	*memory_nodes;
 	unsigned long long	 memory_bsize;
 	u64                     clockid_res_ns;
+	struct rw_semaphore	bpf_info_lock;
+	struct rb_root		bpf_prog_infos;
 };
 
 extern struct perf_env perf_env;
@@ -80,4 +85,8 @@ const char *perf_env__arch(struct perf_env *env);
 const char *perf_env__raw_arch(struct perf_env *env);
 int perf_env__nr_cpus_avail(struct perf_env *env);
 
+void perf_env__insert_bpf_prog_info(struct perf_env *env,
+				    struct bpf_prog_info_node *info_node);
+struct bpf_prog_info_node *perf_env__find_bpf_prog_info(struct perf_env *env,
+							__u32 prog_id);
 #endif /* __PERF_ENV_H */
diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index dec6d218c31c..2ae76a9d06f6 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -1080,6 +1080,51 @@ static int write_clockid(struct feat_fd *ff,
 			sizeof(ff->ph->env.clockid_res_ns));
 }
 
+static int write_bpf_prog_info(struct feat_fd *ff,
+			       struct perf_evlist *evlist __maybe_unused)
+{
+	struct perf_env *env = &ff->ph->env;
+	struct rb_root *root;
+	struct rb_node *next;
+	u32 count = 0;
+	int ret;
+
+	down_read(&env->bpf_info_lock);
+
+	root = &env->bpf_prog_infos;
+	next = rb_first(root);
+	while (next) {
+		++count;
+		next = rb_next(next);
+	}
+
+	ret = do_write(ff, &count, sizeof(count));
+
+	if (ret < 0)
+		goto out;
+
+	next = rb_first(root);
+	while (next) {
+		struct bpf_prog_info_node *node;
+		size_t len;
+
+		node = rb_entry(next, struct bpf_prog_info_node, rb_node);
+		next = rb_next(&node->rb_node);
+		len = sizeof(struct bpf_prog_info_linear) +
+			node->info_linear->data_len;
+
+		/* before writing to file, translate address to offset */
+		bpf_program__bpil_addr_to_offs(node->info_linear);
+		ret = do_write(ff, node->info_linear, len);
+		bpf_program__bpil_offs_to_addr(node->info_linear);
+		if (ret < 0)
+			goto out;
+	}
+out:
+	up_read(&env->bpf_info_lock);
+	return ret;
+}
+
 static int cpu_cache_level__sort(const void *a, const void *b)
 {
 	struct cpu_cache_level *cache_a = (struct cpu_cache_level *)a;
@@ -1560,6 +1605,29 @@ static void print_clockid(struct feat_fd *ff, FILE *fp)
 		ff->ph->env.clockid_res_ns * 1000);
 }
 
+static void print_bpf_prog_info(struct feat_fd *ff, FILE *fp)
+{
+	struct perf_env *env = &ff->ph->env;
+	struct rb_root *root;
+	struct rb_node *next;
+
+	down_read(&env->bpf_info_lock);
+
+	root = &env->bpf_prog_infos;
+	next = rb_first(root);
+
+	while (next) {
+		struct bpf_prog_info_node *node;
+
+		node = rb_entry(next, struct bpf_prog_info_node, rb_node);
+		next = rb_next(&node->rb_node);
+		fprintf(fp, "# bpf_prog_info of id %u\n",
+			node->info_linear->info.id);
+	}
+
+	up_read(&env->bpf_info_lock);
+}
+
 static void free_event_desc(struct perf_evsel *events)
 {
 	struct perf_evsel *evsel;
@@ -2592,6 +2660,69 @@ static int process_clockid(struct feat_fd *ff,
 	return 0;
 }
 
+static int process_bpf_prog_info(struct feat_fd *ff,
+				 void *data __maybe_unused)
+{
+	struct bpf_prog_info_linear *info_linear;
+	struct bpf_prog_info_node *info_node;
+	struct perf_env *env = &ff->ph->env;
+	u32 count, i;
+	int err = -1;
+
+	if (do_read_u32(ff, &count))
+		return -1;
+
+	down_write(&env->bpf_info_lock);
+
+	for (i = 0; i < count; ++i) {
+		u32 info_len, data_len;
+
+		info_linear = NULL;
+		info_node = NULL;
+		if (do_read_u32(ff, &info_len))
+			goto out;
+		if (do_read_u32(ff, &data_len))
+			goto out;
+
+		if (info_len > sizeof(struct bpf_prog_info)) {
+			pr_warning("detected invalid bpf_prog_info\n");
+			goto out;
+		}
+
+		info_linear = malloc(sizeof(struct bpf_prog_info_linear) +
+				     data_len);
+		if (!info_linear)
+			goto out;
+		info_linear->info_len = sizeof(struct bpf_prog_info);
+		info_linear->data_len = data_len;
+		if (do_read_u64(ff, (u64 *)(&info_linear->arrays)))
+			goto out;
+		if (__do_read(ff, &info_linear->info, info_len))
+			goto out;
+		if (info_len < sizeof(struct bpf_prog_info))
+			memset(((void *)(&info_linear->info)) + info_len, 0,
+			       sizeof(struct bpf_prog_info) - info_len);
+
+		if (__do_read(ff, info_linear->data, data_len))
+			goto out;
+		info_node = malloc(sizeof(struct bpf_prog_info_node));
+		if (!info_node)
+			goto out;
+
+		/* after reading from file, translate offset to address */
+		bpf_program__bpil_offs_to_addr(info_linear);
+		info_node->info_linear = info_linear;
+		perf_env__insert_bpf_prog_info(env, info_node);
+	}
+
+	return 0;
+out:
+	free(info_linear);
+	free(info_node);
+	up_write(&env->bpf_info_lock);
+	return err;
+}
+
 struct feature_ops {
 	int (*write)(struct feat_fd *ff, struct perf_evlist *evlist);
 	void (*print)(struct feat_fd *ff, FILE *fp);
@@ -2651,7 +2782,8 @@ static const struct feature_ops feat_ops[HEADER_LAST_FEATURE] = {
 	FEAT_OPN(CACHE,		cache,		true),
 	FEAT_OPR(SAMPLE_TIME,	sample_time,	false),
 	FEAT_OPR(MEM_TOPOLOGY,	mem_topology,	true),
-	FEAT_OPR(CLOCKID,       clockid,        false)
+	FEAT_OPR(CLOCKID,       clockid,        false),
+	FEAT_OPR(BPF_PROG_INFO, bpf_prog_info,  false)
 };
 
 struct header_print_data {
diff --git a/tools/perf/util/header.h b/tools/perf/util/header.h
index 0d553ddca0a3..0785c91b4c3a 100644
--- a/tools/perf/util/header.h
+++ b/tools/perf/util/header.h
@@ -39,6 +39,7 @@ enum {
 	HEADER_SAMPLE_TIME,
 	HEADER_MEM_TOPOLOGY,
 	HEADER_CLOCKID,
+	HEADER_BPF_PROG_INFO,
 	HEADER_LAST_FEATURE,
 	HEADER_FEAT_BITS	= 256,
 };
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 13+ messages in thread

* Re: [PATCH 0/9] perf annotation of BPF programs
  2019-02-09  1:16 [PATCH 0/9] perf annotation of BPF programs Song Liu
                   ` (4 preceding siblings ...)
  2019-02-09  1:17 ` [PATCH 5/9] perf, bpf: save bpf_prog_info in a rbtree in perf_env Song Liu
@ 2019-02-11 18:54 ` Arnaldo Carvalho de Melo
  2019-02-11 20:10   ` Song Liu
  5 siblings, 1 reply; 13+ messages in thread
From: Arnaldo Carvalho de Melo @ 2019-02-11 18:54 UTC (permalink / raw)
  To: Song Liu
  Cc: netdev, linux-kernel, ast, daniel, kernel-team, peterz,
	Jiri Olsa, Namhyung Kim, Andi Kleen, Stephane Eranian,
	Arnaldo Carvalho de Melo

Em Fri, Feb 08, 2019 at 05:16:56PM -0800, Song Liu escreveu:
> This series enables annotation of BPF programs in perf.
> 
> perf tool gathers information via sys_bpf and (optionally) stores them in
> perf.data as headers.

Jiri, Stephane, this is the patchkit I mentioned in the context of doing
away with perf.data headers and instead package everything as userspace
PERF_RECORD_ metadata events.

Song, please add Jiri and Namhyung in future perf patchkits, they are
listed as perf tools reviewers in MAINTAINANERS and Jiri also is working
on something directly related.

Thanks,

- Arnaldo
 
> Patch 1/9 fixes a minor issue in kernel;
> Patch 2/9 to 4/9 introduce new helper functions and use them in perf and
>      bpftool;
> Patch 5/9 and 6/9 saves information of bpf program in perf_env;
> Patch 7/9 adds --bpf-event options to perf-top;
> Patch 8/9 enables annotation of bpf programs based on information gathered
>      in 5/9 and 6/9;
> Patch 9/9 handles information of short living BPF program that are loaded
>      during perf-record or perf-top.
> 
> Commands tested during developments are perf-top, perf-record, perf-report,
> and perf-annotate.
> 
> ===================== Note on patch dependency  ========================
> This set has dependency in both bpf-next tree and tip/perf/core. Current
> version is developed on bpf-next tree with the following commits
> cherry-picked from tip/perf/core:
> 
> (from 1/10 to 10/10)
> commit 76193a94522f ("perf, bpf: Introduce PERF_RECORD_KSYMBOL")
> commit d764ac646491 ("tools headers uapi: Sync tools/include/uapi/linux/perf_event.h")
> commit 6ee52e2a3fe4 ("perf, bpf: Introduce PERF_RECORD_BPF_EVENT")
> commit df063c83aa2c ("tools headers uapi: Sync tools/include/uapi/linux/perf_event.h")
> commit 9aa0bfa370b2 ("perf tools: Handle PERF_RECORD_KSYMBOL")
> commit 45178a928a4b ("perf tools: Handle PERF_RECORD_BPF_EVENT")
> commit 7b612e291a5a ("perf tools: Synthesize PERF_RECORD_* for loaded BPF programs")
> commit a40b95bcd30c ("perf top: Synthesize BPF events for pre-existing loaded BPF programs")
> commit 6934058d9fb6 ("bpf: Add module name [bpf] to ksymbols for bpf programs")
> commit 811184fb6977 ("perf bpf: Fix synthesized PERF_RECORD_KSYMBOL/BPF_EVENT")
> ========================================================================
> 
> Song Liu (9):
>   perf, bpf: consider events with attr.bpf_event as side-band events
>   bpf: libbpf: introduce bpf_program__get_prog_info_linear()
>   bpf: bpftool: use bpf_program__get_prog_info_linear() in
>     prog.c:do_dump()
>   perf, bpf: synthesize bpf events with
>     bpf_program__get_prog_info_linear()
>   perf, bpf: save bpf_prog_info in a rbtree in perf_env
>   perf, bpf: save btf in a rbtree in perf_env
>   perf-top: add option --bpf-event
>   perf, bpf: enable annotation of bpf program
>   perf, bpf: save information about short living bpf programs
> 
>  kernel/events/core.c        |   3 +-
>  tools/bpf/bpftool/prog.c    | 266 ++++++---------------------
>  tools/lib/bpf/libbpf.c      | 251 ++++++++++++++++++++++++++
>  tools/lib/bpf/libbpf.h      |  63 +++++++
>  tools/lib/bpf/libbpf.map    |   3 +
>  tools/perf/Makefile.config  |   2 +-
>  tools/perf/builtin-record.c |  15 +-
>  tools/perf/builtin-top.c    |  15 +-
>  tools/perf/util/annotate.c  | 149 ++++++++++++++-
>  tools/perf/util/bpf-event.c | 351 +++++++++++++++++++++++++++---------
>  tools/perf/util/bpf-event.h |  48 ++++-
>  tools/perf/util/dso.c       |   1 +
>  tools/perf/util/dso.h       |  33 ++--
>  tools/perf/util/env.c       | 148 +++++++++++++++
>  tools/perf/util/env.h       |  12 ++
>  tools/perf/util/evlist.c    |  20 ++
>  tools/perf/util/evlist.h    |   2 +
>  tools/perf/util/header.c    | 231 +++++++++++++++++++++++-
>  tools/perf/util/header.h    |   2 +
>  tools/perf/util/symbol.c    |   1 +
>  20 files changed, 1304 insertions(+), 312 deletions(-)
> 
> --
> 2.17.1

^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH 0/9] perf annotation of BPF programs
  2019-02-11 18:54 ` [PATCH 0/9] perf annotation of BPF programs Arnaldo Carvalho de Melo
@ 2019-02-11 20:10   ` Song Liu
  0 siblings, 0 replies; 13+ messages in thread
From: Song Liu @ 2019-02-11 20:10 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo
  Cc: netdev, linux-kernel, ast, daniel, Kernel Team, peterz,
	Jiri Olsa, Namhyung Kim, Andi Kleen, Stephane Eranian,
	Arnaldo Carvalho de Melo



> On Feb 11, 2019, at 10:54 AM, Arnaldo Carvalho de Melo <acme@redhat.com> wrote:
> 
> Em Fri, Feb 08, 2019 at 05:16:56PM -0800, Song Liu escreveu:
>> This series enables annotation of BPF programs in perf.
>> 
>> perf tool gathers information via sys_bpf and (optionally) stores them in
>> perf.data as headers.
> 
> Jiri, Stephane, this is the patchkit I mentioned in the context of doing
> away with perf.data headers and instead package everything as userspace
> PERF_RECORD_ metadata events.
> 
> Song, please add Jiri and Namhyung in future perf patchkits, they are
> listed as perf tools reviewers in MAINTAINANERS and Jiri also is working
> on something directly related.
> 
> Thanks,
> 
> - Arnaldo

Thanks Arnaldo! I will keep Jiri and Namhyung in the loop. 

Song




>> Patch 1/9 fixes a minor issue in kernel;
>> Patch 2/9 to 4/9 introduce new helper functions and use them in perf and
>>     bpftool;
>> Patch 5/9 and 6/9 saves information of bpf program in perf_env;
>> Patch 7/9 adds --bpf-event options to perf-top;
>> Patch 8/9 enables annotation of bpf programs based on information gathered
>>     in 5/9 and 6/9;
>> Patch 9/9 handles information of short living BPF program that are loaded
>>     during perf-record or perf-top.
>> 
>> Commands tested during developments are perf-top, perf-record, perf-report,
>> and perf-annotate.
>> 
>> ===================== Note on patch dependency  ========================
>> This set has dependency in both bpf-next tree and tip/perf/core. Current
>> version is developed on bpf-next tree with the following commits
>> cherry-picked from tip/perf/core:
>> 
>> (from 1/10 to 10/10)
>> commit 76193a94522f ("perf, bpf: Introduce PERF_RECORD_KSYMBOL")
>> commit d764ac646491 ("tools headers uapi: Sync tools/include/uapi/linux/perf_event.h")
>> commit 6ee52e2a3fe4 ("perf, bpf: Introduce PERF_RECORD_BPF_EVENT")
>> commit df063c83aa2c ("tools headers uapi: Sync tools/include/uapi/linux/perf_event.h")
>> commit 9aa0bfa370b2 ("perf tools: Handle PERF_RECORD_KSYMBOL")
>> commit 45178a928a4b ("perf tools: Handle PERF_RECORD_BPF_EVENT")
>> commit 7b612e291a5a ("perf tools: Synthesize PERF_RECORD_* for loaded BPF programs")
>> commit a40b95bcd30c ("perf top: Synthesize BPF events for pre-existing loaded BPF programs")
>> commit 6934058d9fb6 ("bpf: Add module name [bpf] to ksymbols for bpf programs")
>> commit 811184fb6977 ("perf bpf: Fix synthesized PERF_RECORD_KSYMBOL/BPF_EVENT")
>> ========================================================================
>> 
>> Song Liu (9):
>>  perf, bpf: consider events with attr.bpf_event as side-band events
>>  bpf: libbpf: introduce bpf_program__get_prog_info_linear()
>>  bpf: bpftool: use bpf_program__get_prog_info_linear() in
>>    prog.c:do_dump()
>>  perf, bpf: synthesize bpf events with
>>    bpf_program__get_prog_info_linear()
>>  perf, bpf: save bpf_prog_info in a rbtree in perf_env
>>  perf, bpf: save btf in a rbtree in perf_env
>>  perf-top: add option --bpf-event
>>  perf, bpf: enable annotation of bpf program
>>  perf, bpf: save information about short living bpf programs
>> 
>> kernel/events/core.c        |   3 +-
>> tools/bpf/bpftool/prog.c    | 266 ++++++---------------------
>> tools/lib/bpf/libbpf.c      | 251 ++++++++++++++++++++++++++
>> tools/lib/bpf/libbpf.h      |  63 +++++++
>> tools/lib/bpf/libbpf.map    |   3 +
>> tools/perf/Makefile.config  |   2 +-
>> tools/perf/builtin-record.c |  15 +-
>> tools/perf/builtin-top.c    |  15 +-
>> tools/perf/util/annotate.c  | 149 ++++++++++++++-
>> tools/perf/util/bpf-event.c | 351 +++++++++++++++++++++++++++---------
>> tools/perf/util/bpf-event.h |  48 ++++-
>> tools/perf/util/dso.c       |   1 +
>> tools/perf/util/dso.h       |  33 ++--
>> tools/perf/util/env.c       | 148 +++++++++++++++
>> tools/perf/util/env.h       |  12 ++
>> tools/perf/util/evlist.c    |  20 ++
>> tools/perf/util/evlist.h    |   2 +
>> tools/perf/util/header.c    | 231 +++++++++++++++++++++++-
>> tools/perf/util/header.h    |   2 +
>> tools/perf/util/symbol.c    |   1 +
>> 20 files changed, 1304 insertions(+), 312 deletions(-)
>> 
>> --
>> 2.17.1


^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH 5/9] perf, bpf: save bpf_prog_info in a rbtree in perf_env
  2019-02-09  1:17 ` [PATCH 5/9] perf, bpf: save bpf_prog_info in a rbtree in perf_env Song Liu
@ 2019-02-14 12:26   ` Jiri Olsa
  2019-02-14 17:01     ` Song Liu
  2019-02-14 12:33   ` Jiri Olsa
  1 sibling, 1 reply; 13+ messages in thread
From: Jiri Olsa @ 2019-02-14 12:26 UTC (permalink / raw)
  To: Song Liu; +Cc: netdev, linux-kernel, ast, daniel, kernel-team, peterz, acme

On Fri, Feb 08, 2019 at 05:17:01PM -0800, Song Liu wrote:

SNIP

> diff --git a/tools/perf/util/env.h b/tools/perf/util/env.h
> index d01b8355f4ca..5894a177b7cf 100644
> --- a/tools/perf/util/env.h
> +++ b/tools/perf/util/env.h
> @@ -3,7 +3,10 @@
>  #define __PERF_ENV_H
>  
>  #include <linux/types.h>
> +#include <linux/rbtree.h>
>  #include "cpumap.h"
> +#include "rwsem.h"
> +#include "bpf-event.h"
>  
>  struct cpu_topology_map {
>  	int	socket_id;
> @@ -64,6 +67,8 @@ struct perf_env {
>  	struct memory_node	*memory_nodes;
>  	unsigned long long	 memory_bsize;
>  	u64                     clockid_res_ns;
> +	struct rw_semaphore	bpf_info_lock;

why's the lock needed?

jirka

^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH 5/9] perf, bpf: save bpf_prog_info in a rbtree in perf_env
  2019-02-09  1:17 ` [PATCH 5/9] perf, bpf: save bpf_prog_info in a rbtree in perf_env Song Liu
  2019-02-14 12:26   ` Jiri Olsa
@ 2019-02-14 12:33   ` Jiri Olsa
  2019-02-14 17:03     ` Song Liu
  1 sibling, 1 reply; 13+ messages in thread
From: Jiri Olsa @ 2019-02-14 12:33 UTC (permalink / raw)
  To: Song Liu; +Cc: netdev, linux-kernel, ast, daniel, kernel-team, peterz, acme

On Fri, Feb 08, 2019 at 05:17:01PM -0800, Song Liu wrote:
> bpf_prog_info contains information necessary to annotate bpf programs.
> This patch saves bpf_prog_info for bpf programs loaded in the system.
> 
> perf-record saves bpf_prog_info information as headers to perf.data.
> A new header type HEADER_BPF_PROG_INFO is introduced for this data.

please move those 2 changes into separate patches then

it's hard to make comments when I don't see the rest of
the patches on the list please resend the patchset

thanks,
jirka

^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH 5/9] perf, bpf: save bpf_prog_info in a rbtree in perf_env
  2019-02-14 12:26   ` Jiri Olsa
@ 2019-02-14 17:01     ` Song Liu
  0 siblings, 0 replies; 13+ messages in thread
From: Song Liu @ 2019-02-14 17:01 UTC (permalink / raw)
  To: Jiri Olsa; +Cc: Netdev, linux-kernel, ast, daniel, Kernel Team, peterz, acme



> On Feb 14, 2019, at 4:26 AM, Jiri Olsa <jolsa@redhat.com> wrote:
> 
> On Fri, Feb 08, 2019 at 05:17:01PM -0800, Song Liu wrote:
> 
> SNIP
> 
>> diff --git a/tools/perf/util/env.h b/tools/perf/util/env.h
>> index d01b8355f4ca..5894a177b7cf 100644
>> --- a/tools/perf/util/env.h
>> +++ b/tools/perf/util/env.h
>> @@ -3,7 +3,10 @@
>> #define __PERF_ENV_H
>> 
>> #include <linux/types.h>
>> +#include <linux/rbtree.h>
>> #include "cpumap.h"
>> +#include "rwsem.h"
>> +#include "bpf-event.h"
>> 
>> struct cpu_topology_map {
>> 	int	socket_id;
>> @@ -64,6 +67,8 @@ struct perf_env {
>> 	struct memory_node	*memory_nodes;
>> 	unsigned long long	 memory_bsize;
>> 	u64                     clockid_res_ns;
>> +	struct rw_semaphore	bpf_info_lock;
> 
> why's the lock needed?
> 
> jirka

It protects the retries for bpf_prog_info and btf. For perf-top, 
we will have one thread writing to the trees, while the main 
thread reading from them. 

Let me add comments to clarify. 

Thanks,
Song

^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH 5/9] perf, bpf: save bpf_prog_info in a rbtree in perf_env
  2019-02-14 12:33   ` Jiri Olsa
@ 2019-02-14 17:03     ` Song Liu
  2019-02-15  7:41       ` Jiri Olsa
  0 siblings, 1 reply; 13+ messages in thread
From: Song Liu @ 2019-02-14 17:03 UTC (permalink / raw)
  To: Jiri Olsa; +Cc: Netdev, linux-kernel, ast, daniel, Kernel Team, peterz, acme



> On Feb 14, 2019, at 4:33 AM, Jiri Olsa <jolsa@redhat.com> wrote:
> 
> On Fri, Feb 08, 2019 at 05:17:01PM -0800, Song Liu wrote:
>> bpf_prog_info contains information necessary to annotate bpf programs.
>> This patch saves bpf_prog_info for bpf programs loaded in the system.
>> 
>> perf-record saves bpf_prog_info information as headers to perf.data.
>> A new header type HEADER_BPF_PROG_INFO is introduced for this data.
> 
> please move those 2 changes into separate patches then

Do you mean one patch to save data in rbtree, then a separate patch 
to save data in perf.data file?

Thanks,
Song

> 
> it's hard to make comments when I don't see the rest of
> the patches on the list please resend the patchset
> 
> thanks,
> jirka


^ permalink raw reply	[flat|nested] 13+ messages in thread

* Re: [PATCH 5/9] perf, bpf: save bpf_prog_info in a rbtree in perf_env
  2019-02-14 17:03     ` Song Liu
@ 2019-02-15  7:41       ` Jiri Olsa
  0 siblings, 0 replies; 13+ messages in thread
From: Jiri Olsa @ 2019-02-15  7:41 UTC (permalink / raw)
  To: Song Liu; +Cc: Netdev, linux-kernel, ast, daniel, Kernel Team, peterz, acme

On Thu, Feb 14, 2019 at 05:03:03PM +0000, Song Liu wrote:
> 
> 
> > On Feb 14, 2019, at 4:33 AM, Jiri Olsa <jolsa@redhat.com> wrote:
> > 
> > On Fri, Feb 08, 2019 at 05:17:01PM -0800, Song Liu wrote:
> >> bpf_prog_info contains information necessary to annotate bpf programs.
> >> This patch saves bpf_prog_info for bpf programs loaded in the system.
> >> 
> >> perf-record saves bpf_prog_info information as headers to perf.data.
> >> A new header type HEADER_BPF_PROG_INFO is introduced for this data.
> > 
> > please move those 2 changes into separate patches then
> 
> Do you mean one patch to save data in rbtree, then a separate patch 
> to save data in perf.data file?

yes

jirka

^ permalink raw reply	[flat|nested] 13+ messages in thread

end of thread, other threads:[~2019-02-15  7:42 UTC | newest]

Thread overview: 13+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-02-09  1:16 [PATCH 0/9] perf annotation of BPF programs Song Liu
2019-02-09  1:16 ` [PATCH 1/9] perf, bpf: consider events with attr.bpf_event as side-band events Song Liu
2019-02-09  1:16 ` [PATCH 2/9] bpf: libbpf: introduce bpf_program__get_prog_info_linear() Song Liu
2019-02-09  1:16 ` [PATCH 3/9] bpf: bpftool: use bpf_program__get_prog_info_linear() in prog.c:do_dump() Song Liu
2019-02-09  1:17 ` [PATCH 4/9] perf, bpf: synthesize bpf events with bpf_program__get_prog_info_linear() Song Liu
2019-02-09  1:17 ` [PATCH 5/9] perf, bpf: save bpf_prog_info in a rbtree in perf_env Song Liu
2019-02-14 12:26   ` Jiri Olsa
2019-02-14 17:01     ` Song Liu
2019-02-14 12:33   ` Jiri Olsa
2019-02-14 17:03     ` Song Liu
2019-02-15  7:41       ` Jiri Olsa
2019-02-11 18:54 ` [PATCH 0/9] perf annotation of BPF programs Arnaldo Carvalho de Melo
2019-02-11 20:10   ` Song Liu

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