* [PATCH v2 1/4] perf test: Keep test result clean if '-v' not set
2015-11-04 2:25 [PATCH v2 0/4] perf bpf: Improve error code delivering and output Wang Nan
@ 2015-11-04 2:25 ` Wang Nan
2015-11-04 2:25 ` [PATCH v2 2/4] perf tools: Mute libbpf when " Wang Nan
` (2 subsequent siblings)
3 siblings, 0 replies; 8+ messages in thread
From: Wang Nan @ 2015-11-04 2:25 UTC (permalink / raw)
To: acme, namhyung
Cc: lizefan, pi3orama, linux-kernel, Wang Nan,
Arnaldo Carvalho de Melo
According to [1], 'perf state' should avoid output too much information
if '-v' not set, only 'Ok', 'FAIL' or 'Skip' need to be printed.
This patch removes sereval stderr output to make output clean.
Before this patch:
# perf test dummy
23: Test using a dummy software event to keep tracking : (not supported) Ok
After this patch:
# perf test dummy
23: Test using a dummy software event to keep tracking : Skip
[1] http://lkml.kernel.org/r/20151020134155.GE4400@redhat.com
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/n/tip-446450727-218554-1-git-send-email-wangnan0@huawei.com
---
tools/perf/tests/attr.c | 3 +--
tools/perf/tests/code-reading.c | 8 ++++----
tools/perf/tests/keep-tracking.c | 4 ++--
tools/perf/tests/llvm.c | 11 ++++-------
tools/perf/tests/switch-tracking.c | 4 ++--
5 files changed, 13 insertions(+), 17 deletions(-)
diff --git a/tools/perf/tests/attr.c b/tools/perf/tests/attr.c
index 2dfc9ad..638875a 100644
--- a/tools/perf/tests/attr.c
+++ b/tools/perf/tests/attr.c
@@ -171,6 +171,5 @@ int test__attr(void)
!lstat(path_perf, &st))
return run_dir(path_dir, path_perf);
- fprintf(stderr, " (omitted)");
- return 0;
+ return TEST_SKIP;
}
diff --git a/tools/perf/tests/code-reading.c b/tools/perf/tests/code-reading.c
index 49b1959..a767a64 100644
--- a/tools/perf/tests/code-reading.c
+++ b/tools/perf/tests/code-reading.c
@@ -613,16 +613,16 @@ int test__code_reading(void)
case TEST_CODE_READING_OK:
return 0;
case TEST_CODE_READING_NO_VMLINUX:
- fprintf(stderr, " (no vmlinux)");
+ pr_debug("no vmlinux\n");
return 0;
case TEST_CODE_READING_NO_KCORE:
- fprintf(stderr, " (no kcore)");
+ pr_debug("no kcore\n");
return 0;
case TEST_CODE_READING_NO_ACCESS:
- fprintf(stderr, " (no access)");
+ pr_debug("no access\n");
return 0;
case TEST_CODE_READING_NO_KERNEL_OBJ:
- fprintf(stderr, " (no kernel obj)");
+ pr_debug("no kernel obj\n");
return 0;
default:
return -1;
diff --git a/tools/perf/tests/keep-tracking.c b/tools/perf/tests/keep-tracking.c
index 4d4b983..a2e2269 100644
--- a/tools/perf/tests/keep-tracking.c
+++ b/tools/perf/tests/keep-tracking.c
@@ -90,8 +90,8 @@ int test__keep_tracking(void)
evsel->attr.enable_on_exec = 0;
if (perf_evlist__open(evlist) < 0) {
- fprintf(stderr, " (not supported)");
- err = 0;
+ pr_debug("Unable to open dummy and cycles event\n");
+ err = TEST_SKIP;
goto out_err;
}
diff --git a/tools/perf/tests/llvm.c b/tools/perf/tests/llvm.c
index 52d5597..512d362 100644
--- a/tools/perf/tests/llvm.c
+++ b/tools/perf/tests/llvm.c
@@ -36,7 +36,7 @@ static int test__bpf_parsing(void *obj_buf, size_t obj_buf_sz)
static int test__bpf_parsing(void *obj_buf __maybe_unused,
size_t obj_buf_sz __maybe_unused)
{
- fprintf(stderr, " (skip bpf parsing)");
+ pr_debug("Skip bpf parsing\n");
return 0;
}
#endif
@@ -55,7 +55,7 @@ int test__llvm(void)
* and clang is not found in $PATH, and this is not perf test -v
*/
if (verbose == 0 && !llvm_param.user_set_param && llvm__search_clang()) {
- fprintf(stderr, " (no clang, try 'perf test -v LLVM')");
+ pr_debug("No clang and no verbosive, skip this test\n");
return TEST_SKIP;
}
@@ -86,11 +86,8 @@ int test__llvm(void)
err = llvm__compile_bpf("-", &obj_buf, &obj_buf_sz);
verbose = old_verbose;
- if (err) {
- if (!verbose)
- fprintf(stderr, " (use -v to see error message)");
- return -1;
- }
+ if (err)
+ return TEST_FAIL;
err = test__bpf_parsing(obj_buf, obj_buf_sz);
free(obj_buf);
diff --git a/tools/perf/tests/switch-tracking.c b/tools/perf/tests/switch-tracking.c
index e698742..a02af50 100644
--- a/tools/perf/tests/switch-tracking.c
+++ b/tools/perf/tests/switch-tracking.c
@@ -366,7 +366,7 @@ int test__switch_tracking(void)
/* Third event */
if (!perf_evlist__can_select_event(evlist, sched_switch)) {
- fprintf(stderr, " (no sched_switch)");
+ pr_debug("No sched_switch\n");
err = 0;
goto out;
}
@@ -442,7 +442,7 @@ int test__switch_tracking(void)
}
if (perf_evlist__open(evlist) < 0) {
- fprintf(stderr, " (not supported)");
+ pr_debug("Not supported\n");
err = 0;
goto out;
}
--
1.8.3.4
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCH v2 2/4] perf tools: Mute libbpf when '-v' not set
2015-11-04 2:25 [PATCH v2 0/4] perf bpf: Improve error code delivering and output Wang Nan
2015-11-04 2:25 ` [PATCH v2 1/4] perf test: Keep test result clean if '-v' not set Wang Nan
@ 2015-11-04 2:25 ` Wang Nan
2015-11-04 2:25 ` [PATCH v2 3/4] bpf tools: Improve libbpf error reporting Wang Nan
2015-11-04 2:25 ` [PATCH v2 4/4] perf tools: Improve BPF related error messages output Wang Nan
3 siblings, 0 replies; 8+ messages in thread
From: Wang Nan @ 2015-11-04 2:25 UTC (permalink / raw)
To: acme, namhyung
Cc: lizefan, pi3orama, linux-kernel, Wang Nan,
Arnaldo Carvalho de Melo
According to [1], libbpf should be muted. This patch reset info and
warning message level to ensure libbpf doesn't output anything even
if error happened.
[1] http://lkml.kernel.org/r/20151020151255.GF5119@kernel.org
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
---
tools/perf/util/bpf-loader.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c
index ba6f752..0c5d174 100644
--- a/tools/perf/util/bpf-loader.c
+++ b/tools/perf/util/bpf-loader.c
@@ -26,8 +26,8 @@ static int libbpf_##name(const char *fmt, ...) \
return ret; \
}
-DEFINE_PRINT_FN(warning, 0)
-DEFINE_PRINT_FN(info, 0)
+DEFINE_PRINT_FN(warning, 1)
+DEFINE_PRINT_FN(info, 1)
DEFINE_PRINT_FN(debug, 1)
struct bpf_prog_priv {
--
1.8.3.4
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCH v2 3/4] bpf tools: Improve libbpf error reporting
2015-11-04 2:25 [PATCH v2 0/4] perf bpf: Improve error code delivering and output Wang Nan
2015-11-04 2:25 ` [PATCH v2 1/4] perf test: Keep test result clean if '-v' not set Wang Nan
2015-11-04 2:25 ` [PATCH v2 2/4] perf tools: Mute libbpf when " Wang Nan
@ 2015-11-04 2:25 ` Wang Nan
2015-11-04 22:01 ` Arnaldo Carvalho de Melo
2015-11-04 2:25 ` [PATCH v2 4/4] perf tools: Improve BPF related error messages output Wang Nan
3 siblings, 1 reply; 8+ messages in thread
From: Wang Nan @ 2015-11-04 2:25 UTC (permalink / raw)
To: acme, namhyung
Cc: lizefan, pi3orama, linux-kernel, Wang Nan,
Arnaldo Carvalho de Melo
In this patch, a series libbpf specific error numbers and
libbpf_strerror() are created to help reporting error to caller.
Functions are updated to pass correct error number through macro
CHECK_ERR().
All users of bpf_object__open{_buffer}() and bpf_program__title()
in perf are modified accordingly.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
---
tools/lib/bpf/libbpf.c | 149 ++++++++++++++++++++++++++++-------------
tools/lib/bpf/libbpf.h | 12 ++++
tools/perf/tests/llvm.c | 2 +-
tools/perf/util/bpf-loader.c | 8 +--
tools/perf/util/parse-events.c | 4 +-
5 files changed, 120 insertions(+), 55 deletions(-)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 4252fc2..74c64b1 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -61,6 +61,62 @@ void libbpf_set_print(libbpf_print_fn_t warn,
__pr_debug = debug;
}
+#define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0]))
+#define STRERR_BUFSIZE 128
+
+struct {
+ int code;
+ const char *msg;
+} libbpf_strerror_table[] = {
+ {LIBBPF_ERRNO__ELIBELF, "Something wrong in libelf"},
+ {LIBBPF_ERRNO__EFORMAT, "BPF object format invalid"},
+ {LIBBPF_ERRNO__EKVERSION, "'version' section incorrect or lost"},
+ {LIBBPF_ERRNO__EENDIAN, "Endian missmatch"},
+ {LIBBPF_ERRNO__EINTERNAL, "Internal error in libbpf"},
+ {LIBBPF_ERRNO__ERELOC, "Relocation failed"},
+ {LIBBPF_ERRNO__ELOAD, "Failed to load program"},
+};
+
+int libbpf_strerror(int err, char *buf, size_t size)
+{
+ unsigned int i;
+
+ if (!buf || !size)
+ return -1;
+
+ err = err > 0 ? err : -err;
+
+ if (err < LIBBPF_ERRNO__START) {
+ int ret;
+
+ ret = strerror_r(err, buf, size);
+ buf[size - 1] = '\0';
+ return ret;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(libbpf_strerror_table); i++) {
+ if (libbpf_strerror_table[i].code == err) {
+ const char *msg;
+
+ msg = libbpf_strerror_table[i].msg;
+ snprintf(buf, size, "%s", msg);
+ buf[size - 1] = '\0';
+ return 0;
+ }
+ }
+
+ snprintf(buf, size, "Unknown libbpf error %d", err);
+ buf[size - 1] = '\0';
+ return -1;
+}
+
+#define CHECK_ERR(action, err, out) do { \
+ err = action; \
+ if (err) \
+ goto out; \
+} while(0)
+
+
/* Copied from tools/perf/util/util.h */
#ifndef zfree
# define zfree(ptr) ({ free(*ptr); *ptr = NULL; })
@@ -258,7 +314,7 @@ static struct bpf_object *bpf_object__new(const char *path,
obj = calloc(1, sizeof(struct bpf_object) + strlen(path) + 1);
if (!obj) {
pr_warning("alloc memory failed for %s\n", path);
- return NULL;
+ return ERR_PTR(-ENOMEM);
}
strcpy(obj->path, path);
@@ -305,7 +361,7 @@ static int bpf_object__elf_init(struct bpf_object *obj)
if (obj_elf_valid(obj)) {
pr_warning("elf init: internal error\n");
- return -EEXIST;
+ return -LIBBPF_ERRNO__ELIBELF;
}
if (obj->efile.obj_buf_sz > 0) {
@@ -331,14 +387,14 @@ static int bpf_object__elf_init(struct bpf_object *obj)
if (!obj->efile.elf) {
pr_warning("failed to open %s as ELF file\n",
obj->path);
- err = -EINVAL;
+ err = -LIBBPF_ERRNO__ELIBELF;
goto errout;
}
if (!gelf_getehdr(obj->efile.elf, &obj->efile.ehdr)) {
pr_warning("failed to get EHDR from %s\n",
obj->path);
- err = -EINVAL;
+ err = -LIBBPF_ERRNO__EFORMAT;
goto errout;
}
ep = &obj->efile.ehdr;
@@ -346,7 +402,7 @@ static int bpf_object__elf_init(struct bpf_object *obj)
if ((ep->e_type != ET_REL) || (ep->e_machine != 0)) {
pr_warning("%s is not an eBPF object file\n",
obj->path);
- err = -EINVAL;
+ err = -LIBBPF_ERRNO__EFORMAT;
goto errout;
}
@@ -374,14 +430,14 @@ bpf_object__check_endianness(struct bpf_object *obj)
goto mismatch;
break;
default:
- return -EINVAL;
+ return -LIBBPF_ERRNO__EENDIAN;
}
return 0;
mismatch:
pr_warning("Error: endianness mismatch.\n");
- return -EINVAL;
+ return -LIBBPF_ERRNO__EENDIAN;
}
static int
@@ -402,7 +458,7 @@ bpf_object__init_kversion(struct bpf_object *obj,
if (size != sizeof(kver)) {
pr_warning("invalid kver section in %s\n", obj->path);
- return -EINVAL;
+ return -LIBBPF_ERRNO__EFORMAT;
}
memcpy(&kver, data, sizeof(kver));
obj->kern_version = kver;
@@ -444,7 +500,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
if (!elf_rawdata(elf_getscn(elf, ep->e_shstrndx), NULL)) {
pr_warning("failed to get e_shstrndx from %s\n",
obj->path);
- return -EINVAL;
+ return -LIBBPF_ERRNO__EFORMAT;
}
while ((scn = elf_nextscn(elf, scn)) != NULL) {
@@ -456,7 +512,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
if (gelf_getshdr(scn, &sh) != &sh) {
pr_warning("failed to get section header from %s\n",
obj->path);
- err = -EINVAL;
+ err = -LIBBPF_ERRNO__EFORMAT;
goto out;
}
@@ -464,7 +520,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
if (!name) {
pr_warning("failed to get section name from %s\n",
obj->path);
- err = -EINVAL;
+ err = -LIBBPF_ERRNO__EFORMAT;
goto out;
}
@@ -472,7 +528,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
if (!data) {
pr_warning("failed to get section data from %s(%s)\n",
name, obj->path);
- err = -EINVAL;
+ err = -LIBBPF_ERRNO__EFORMAT;
goto out;
}
pr_debug("section %s, size %ld, link %d, flags %lx, type=%d\n",
@@ -495,7 +551,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
if (obj->efile.symbols) {
pr_warning("bpf: multiple SYMTAB in %s\n",
obj->path);
- err = -EEXIST;
+ err = -LIBBPF_ERRNO__EFORMAT;
} else
obj->efile.symbols = data;
} else if ((sh.sh_type == SHT_PROGBITS) &&
@@ -504,7 +560,8 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
err = bpf_object__add_program(obj, data->d_buf,
data->d_size, name, idx);
if (err) {
- char errmsg[128];
+ char errmsg[STRERR_BUFSIZE];
+
strerror_r(-err, errmsg, sizeof(errmsg));
pr_warning("failed to alloc program %s (%s): %s",
name, obj->path, errmsg);
@@ -576,7 +633,7 @@ bpf_program__collect_reloc(struct bpf_program *prog,
if (!gelf_getrel(data, i, &rel)) {
pr_warning("relocation: failed to get %d reloc\n", i);
- return -EINVAL;
+ return -LIBBPF_ERRNO__EFORMAT;
}
insn_idx = rel.r_offset / sizeof(struct bpf_insn);
@@ -587,20 +644,20 @@ bpf_program__collect_reloc(struct bpf_program *prog,
&sym)) {
pr_warning("relocation: symbol %"PRIx64" not found\n",
GELF_R_SYM(rel.r_info));
- return -EINVAL;
+ return -LIBBPF_ERRNO__EFORMAT;
}
if (insns[insn_idx].code != (BPF_LD | BPF_IMM | BPF_DW)) {
pr_warning("bpf: relocation: invalid relo for insns[%d].code 0x%x\n",
insn_idx, insns[insn_idx].code);
- return -EINVAL;
+ return -LIBBPF_ERRNO__ERELOC;
}
map_idx = sym.st_value / sizeof(struct bpf_map_def);
if (map_idx >= nr_maps) {
pr_warning("bpf relocation: map_idx %d large than %d\n",
(int)map_idx, (int)nr_maps - 1);
- return -EINVAL;
+ return -LIBBPF_ERRNO__ERELOC;
}
prog->reloc_desc[i].insn_idx = insn_idx;
@@ -683,7 +740,7 @@ bpf_program__relocate(struct bpf_program *prog, int *map_fds)
if (insn_idx >= (int)prog->insns_cnt) {
pr_warning("relocation out of range: '%s'\n",
prog->section_name);
- return -ERANGE;
+ return -LIBBPF_ERRNO__ERELOC;
}
insns[insn_idx].src_reg = BPF_PSEUDO_MAP_FD;
insns[insn_idx].imm = map_fds[map_idx];
@@ -721,7 +778,7 @@ static int bpf_object__collect_reloc(struct bpf_object *obj)
if (!obj_elf_valid(obj)) {
pr_warning("Internal error: elf object is closed\n");
- return -EINVAL;
+ return -LIBBPF_ERRNO__EINTERNAL;
}
for (i = 0; i < obj->efile.nr_reloc; i++) {
@@ -734,21 +791,21 @@ static int bpf_object__collect_reloc(struct bpf_object *obj)
if (shdr->sh_type != SHT_REL) {
pr_warning("internal error at %d\n", __LINE__);
- return -EINVAL;
+ return -LIBBPF_ERRNO__EINTERNAL;
}
prog = bpf_object__find_prog_by_idx(obj, idx);
if (!prog) {
pr_warning("relocation failed: no %d section\n",
idx);
- return -ENOENT;
+ return -LIBBPF_ERRNO__ERELOC;
}
err = bpf_program__collect_reloc(prog, nr_maps,
shdr, data,
obj->efile.symbols);
if (err)
- return -EINVAL;
+ return err;
}
return 0;
}
@@ -777,7 +834,7 @@ load_program(struct bpf_insn *insns, int insns_cnt,
goto out;
}
- ret = -EINVAL;
+ ret = -LIBBPF_ERRNO__ELOAD;
pr_warning("load bpf program failed: %s\n", strerror(errno));
if (log_buf) {
@@ -831,7 +888,7 @@ static int bpf_object__validate(struct bpf_object *obj)
if (obj->kern_version == 0) {
pr_warning("%s doesn't provide kernel version\n",
obj->path);
- return -EINVAL;
+ return -LIBBPF_ERRNO__EKVERSION;
}
return 0;
}
@@ -840,32 +897,28 @@ static struct bpf_object *
__bpf_object__open(const char *path, void *obj_buf, size_t obj_buf_sz)
{
struct bpf_object *obj;
+ int err;
if (elf_version(EV_CURRENT) == EV_NONE) {
pr_warning("failed to init libelf for %s\n", path);
- return NULL;
+ return ERR_PTR(-LIBBPF_ERRNO__ELIBELF);
}
obj = bpf_object__new(path, obj_buf, obj_buf_sz);
- if (!obj)
- return NULL;
+ if (IS_ERR(obj))
+ return obj;
- if (bpf_object__elf_init(obj))
- goto out;
- if (bpf_object__check_endianness(obj))
- goto out;
- if (bpf_object__elf_collect(obj))
- goto out;
- if (bpf_object__collect_reloc(obj))
- goto out;
- if (bpf_object__validate(obj))
- goto out;
+ CHECK_ERR(bpf_object__elf_init(obj), err, out);
+ CHECK_ERR(bpf_object__check_endianness(obj), err, out);
+ CHECK_ERR(bpf_object__elf_collect(obj), err, out);
+ CHECK_ERR(bpf_object__collect_reloc(obj), err, out);
+ CHECK_ERR(bpf_object__validate(obj), err, out);
bpf_object__elf_finish(obj);
return obj;
out:
bpf_object__close(obj);
- return NULL;
+ return ERR_PTR(err);
}
struct bpf_object *bpf_object__open(const char *path)
@@ -922,6 +975,8 @@ int bpf_object__unload(struct bpf_object *obj)
int bpf_object__load(struct bpf_object *obj)
{
+ int err;
+
if (!obj)
return -EINVAL;
@@ -931,18 +986,16 @@ int bpf_object__load(struct bpf_object *obj)
}
obj->loaded = true;
- if (bpf_object__create_maps(obj))
- goto out;
- if (bpf_object__relocate(obj))
- goto out;
- if (bpf_object__load_progs(obj))
- goto out;
+
+ CHECK_ERR(bpf_object__create_maps(obj), err, out);
+ CHECK_ERR(bpf_object__relocate(obj), err, out);
+ CHECK_ERR(bpf_object__load_progs(obj), err, out);
return 0;
out:
bpf_object__unload(obj);
pr_warning("failed to load object '%s'\n", obj->path);
- return -EINVAL;
+ return err;
}
void bpf_object__close(struct bpf_object *obj)
@@ -990,7 +1043,7 @@ const char *
bpf_object__get_name(struct bpf_object *obj)
{
if (!obj)
- return NULL;
+ return ERR_PTR(-EINVAL);
return obj->path;
}
@@ -1043,7 +1096,7 @@ const char *bpf_program__title(struct bpf_program *prog, bool dup)
title = strdup(title);
if (!title) {
pr_warning("failed to strdup program title\n");
- return NULL;
+ return ERR_PTR(-ENOMEM);
}
}
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index f16170c..c2606ae 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -10,6 +10,18 @@
#include <stdio.h>
#include <stdbool.h>
+#include <linux/err.h>
+
+#define LIBBPF_ERRNO__START 4000
+#define LIBBPF_ERRNO__ELIBELF 4000 /* Something wrong in libelf */
+#define LIBBPF_ERRNO__EFORMAT 4001 /* BPF object format invalid */
+#define LIBBPF_ERRNO__EKVERSION 4002 /* Incorrect or no 'version' section */
+#define LIBBPF_ERRNO__EENDIAN 4003 /* Endian missmatch */
+#define LIBBPF_ERRNO__EINTERNAL 4004 /* Internal error in libbpf */
+#define LIBBPF_ERRNO__ERELOC 4005 /* Relocation failed */
+#define LIBBPF_ERRNO__ELOAD 4006 /* Failed to load program */
+
+int libbpf_strerror(int err, char *buf, size_t size);
/*
* In include/linux/compiler-gcc.h, __printf is defined. However
diff --git a/tools/perf/tests/llvm.c b/tools/perf/tests/llvm.c
index 512d362..8f713f6 100644
--- a/tools/perf/tests/llvm.c
+++ b/tools/perf/tests/llvm.c
@@ -27,7 +27,7 @@ static int test__bpf_parsing(void *obj_buf, size_t obj_buf_sz)
struct bpf_object *obj;
obj = bpf_object__open_buffer(obj_buf, obj_buf_sz, NULL);
- if (!obj)
+ if (IS_ERR(obj))
return -1;
bpf_object__close(obj);
return 0;
diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c
index 0c5d174..76f07ce 100644
--- a/tools/perf/util/bpf-loader.c
+++ b/tools/perf/util/bpf-loader.c
@@ -59,9 +59,9 @@ struct bpf_object *bpf__prepare_load(const char *filename, bool source)
} else
obj = bpf_object__open(filename);
- if (!obj) {
+ if (IS_ERR(obj)) {
pr_debug("bpf: failed to load %s\n", filename);
- return ERR_PTR(-EINVAL);
+ return obj;
}
return obj;
@@ -96,9 +96,9 @@ config_bpf_program(struct bpf_program *prog)
int err;
config_str = bpf_program__title(prog, false);
- if (!config_str) {
+ if (IS_ERR(config_str)) {
pr_debug("bpf: unable to get title for program\n");
- return -EINVAL;
+ return PTR_ERR(config_str);
}
priv = calloc(sizeof(*priv), 1);
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index bee6058..c75b25d 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -632,11 +632,11 @@ int parse_events_load_bpf(struct parse_events_evlist *data,
struct bpf_object *obj;
obj = bpf__prepare_load(bpf_file_name, source);
- if (IS_ERR(obj) || !obj) {
+ if (IS_ERR(obj)) {
char errbuf[BUFSIZ];
int err;
- err = obj ? PTR_ERR(obj) : -EINVAL;
+ err = PTR_ERR(obj);
if (err == -ENOTSUP)
snprintf(errbuf, sizeof(errbuf),
--
1.8.3.4
^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: [PATCH v2 3/4] bpf tools: Improve libbpf error reporting
2015-11-04 2:25 ` [PATCH v2 3/4] bpf tools: Improve libbpf error reporting Wang Nan
@ 2015-11-04 22:01 ` Arnaldo Carvalho de Melo
2015-11-05 1:48 ` Wangnan (F)
0 siblings, 1 reply; 8+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-11-04 22:01 UTC (permalink / raw)
To: Wang Nan; +Cc: namhyung, lizefan, pi3orama, linux-kernel
Em Wed, Nov 04, 2015 at 02:25:58AM +0000, Wang Nan escreveu:
> In this patch, a series libbpf specific error numbers and
> libbpf_strerror() are created to help reporting error to caller.
> Functions are updated to pass correct error number through macro
> CHECK_ERR().
>
> All users of bpf_object__open{_buffer}() and bpf_program__title()
> in perf are modified accordingly.
So, before I get:
[root@zoo ~]# perf record -e /tmp/foo.o sleep 1
event syntax error: '/tmp/foo.o'
\___ Invalid argument: Are you root and runing a CONFIG_BPF_SYSCALL kernel?
(add -v to see detail)
Run 'perf list' for a list of valid events
Usage: perf record [<options>] [<command>]
or: perf record [<options>] -- <command> [<options>]
-e, --event <event> event selector. use 'perf list' to list available events
And now:
[root@zoo ~]# perf record -e /tmp/foo.o sleep 1
event syntax error: '/tmp/foo.o'
\___ Unknown error 4006
(add -v to see detail)
Run 'perf list' for a list of valid events
Usage: perf record [<options>] [<command>]
or: perf record [<options>] -- <command> [<options>]
-e, --event <event> event selector. use 'perf list' to list available events
[root@zoo ~]#
Can you please fix this? The relevant strerror() routine should know about the
errors it handles and produce an informative message.
- Arnaldo
> Signed-off-by: Wang Nan <wangnan0@huawei.com>
> Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
> Cc: Namhyung Kim <namhyung@kernel.org>
> ---
> tools/lib/bpf/libbpf.c | 149 ++++++++++++++++++++++++++++-------------
> tools/lib/bpf/libbpf.h | 12 ++++
> tools/perf/tests/llvm.c | 2 +-
> tools/perf/util/bpf-loader.c | 8 +--
> tools/perf/util/parse-events.c | 4 +-
> 5 files changed, 120 insertions(+), 55 deletions(-)
>
> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
> index 4252fc2..74c64b1 100644
> --- a/tools/lib/bpf/libbpf.c
> +++ b/tools/lib/bpf/libbpf.c
> @@ -61,6 +61,62 @@ void libbpf_set_print(libbpf_print_fn_t warn,
> __pr_debug = debug;
> }
>
> +#define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0]))
> +#define STRERR_BUFSIZE 128
> +
> +struct {
> + int code;
> + const char *msg;
> +} libbpf_strerror_table[] = {
> + {LIBBPF_ERRNO__ELIBELF, "Something wrong in libelf"},
> + {LIBBPF_ERRNO__EFORMAT, "BPF object format invalid"},
> + {LIBBPF_ERRNO__EKVERSION, "'version' section incorrect or lost"},
> + {LIBBPF_ERRNO__EENDIAN, "Endian missmatch"},
> + {LIBBPF_ERRNO__EINTERNAL, "Internal error in libbpf"},
> + {LIBBPF_ERRNO__ERELOC, "Relocation failed"},
> + {LIBBPF_ERRNO__ELOAD, "Failed to load program"},
> +};
> +
> +int libbpf_strerror(int err, char *buf, size_t size)
> +{
> + unsigned int i;
> +
> + if (!buf || !size)
> + return -1;
> +
> + err = err > 0 ? err : -err;
> +
> + if (err < LIBBPF_ERRNO__START) {
> + int ret;
> +
> + ret = strerror_r(err, buf, size);
> + buf[size - 1] = '\0';
> + return ret;
> + }
> +
> + for (i = 0; i < ARRAY_SIZE(libbpf_strerror_table); i++) {
> + if (libbpf_strerror_table[i].code == err) {
> + const char *msg;
> +
> + msg = libbpf_strerror_table[i].msg;
> + snprintf(buf, size, "%s", msg);
> + buf[size - 1] = '\0';
> + return 0;
> + }
> + }
> +
> + snprintf(buf, size, "Unknown libbpf error %d", err);
> + buf[size - 1] = '\0';
> + return -1;
> +}
> +
> +#define CHECK_ERR(action, err, out) do { \
> + err = action; \
> + if (err) \
> + goto out; \
> +} while(0)
> +
> +
> /* Copied from tools/perf/util/util.h */
> #ifndef zfree
> # define zfree(ptr) ({ free(*ptr); *ptr = NULL; })
> @@ -258,7 +314,7 @@ static struct bpf_object *bpf_object__new(const char *path,
> obj = calloc(1, sizeof(struct bpf_object) + strlen(path) + 1);
> if (!obj) {
> pr_warning("alloc memory failed for %s\n", path);
> - return NULL;
> + return ERR_PTR(-ENOMEM);
> }
>
> strcpy(obj->path, path);
> @@ -305,7 +361,7 @@ static int bpf_object__elf_init(struct bpf_object *obj)
>
> if (obj_elf_valid(obj)) {
> pr_warning("elf init: internal error\n");
> - return -EEXIST;
> + return -LIBBPF_ERRNO__ELIBELF;
> }
>
> if (obj->efile.obj_buf_sz > 0) {
> @@ -331,14 +387,14 @@ static int bpf_object__elf_init(struct bpf_object *obj)
> if (!obj->efile.elf) {
> pr_warning("failed to open %s as ELF file\n",
> obj->path);
> - err = -EINVAL;
> + err = -LIBBPF_ERRNO__ELIBELF;
> goto errout;
> }
>
> if (!gelf_getehdr(obj->efile.elf, &obj->efile.ehdr)) {
> pr_warning("failed to get EHDR from %s\n",
> obj->path);
> - err = -EINVAL;
> + err = -LIBBPF_ERRNO__EFORMAT;
> goto errout;
> }
> ep = &obj->efile.ehdr;
> @@ -346,7 +402,7 @@ static int bpf_object__elf_init(struct bpf_object *obj)
> if ((ep->e_type != ET_REL) || (ep->e_machine != 0)) {
> pr_warning("%s is not an eBPF object file\n",
> obj->path);
> - err = -EINVAL;
> + err = -LIBBPF_ERRNO__EFORMAT;
> goto errout;
> }
>
> @@ -374,14 +430,14 @@ bpf_object__check_endianness(struct bpf_object *obj)
> goto mismatch;
> break;
> default:
> - return -EINVAL;
> + return -LIBBPF_ERRNO__EENDIAN;
> }
>
> return 0;
>
> mismatch:
> pr_warning("Error: endianness mismatch.\n");
> - return -EINVAL;
> + return -LIBBPF_ERRNO__EENDIAN;
> }
>
> static int
> @@ -402,7 +458,7 @@ bpf_object__init_kversion(struct bpf_object *obj,
>
> if (size != sizeof(kver)) {
> pr_warning("invalid kver section in %s\n", obj->path);
> - return -EINVAL;
> + return -LIBBPF_ERRNO__EFORMAT;
> }
> memcpy(&kver, data, sizeof(kver));
> obj->kern_version = kver;
> @@ -444,7 +500,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
> if (!elf_rawdata(elf_getscn(elf, ep->e_shstrndx), NULL)) {
> pr_warning("failed to get e_shstrndx from %s\n",
> obj->path);
> - return -EINVAL;
> + return -LIBBPF_ERRNO__EFORMAT;
> }
>
> while ((scn = elf_nextscn(elf, scn)) != NULL) {
> @@ -456,7 +512,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
> if (gelf_getshdr(scn, &sh) != &sh) {
> pr_warning("failed to get section header from %s\n",
> obj->path);
> - err = -EINVAL;
> + err = -LIBBPF_ERRNO__EFORMAT;
> goto out;
> }
>
> @@ -464,7 +520,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
> if (!name) {
> pr_warning("failed to get section name from %s\n",
> obj->path);
> - err = -EINVAL;
> + err = -LIBBPF_ERRNO__EFORMAT;
> goto out;
> }
>
> @@ -472,7 +528,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
> if (!data) {
> pr_warning("failed to get section data from %s(%s)\n",
> name, obj->path);
> - err = -EINVAL;
> + err = -LIBBPF_ERRNO__EFORMAT;
> goto out;
> }
> pr_debug("section %s, size %ld, link %d, flags %lx, type=%d\n",
> @@ -495,7 +551,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
> if (obj->efile.symbols) {
> pr_warning("bpf: multiple SYMTAB in %s\n",
> obj->path);
> - err = -EEXIST;
> + err = -LIBBPF_ERRNO__EFORMAT;
> } else
> obj->efile.symbols = data;
> } else if ((sh.sh_type == SHT_PROGBITS) &&
> @@ -504,7 +560,8 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
> err = bpf_object__add_program(obj, data->d_buf,
> data->d_size, name, idx);
> if (err) {
> - char errmsg[128];
> + char errmsg[STRERR_BUFSIZE];
> +
> strerror_r(-err, errmsg, sizeof(errmsg));
> pr_warning("failed to alloc program %s (%s): %s",
> name, obj->path, errmsg);
> @@ -576,7 +633,7 @@ bpf_program__collect_reloc(struct bpf_program *prog,
>
> if (!gelf_getrel(data, i, &rel)) {
> pr_warning("relocation: failed to get %d reloc\n", i);
> - return -EINVAL;
> + return -LIBBPF_ERRNO__EFORMAT;
> }
>
> insn_idx = rel.r_offset / sizeof(struct bpf_insn);
> @@ -587,20 +644,20 @@ bpf_program__collect_reloc(struct bpf_program *prog,
> &sym)) {
> pr_warning("relocation: symbol %"PRIx64" not found\n",
> GELF_R_SYM(rel.r_info));
> - return -EINVAL;
> + return -LIBBPF_ERRNO__EFORMAT;
> }
>
> if (insns[insn_idx].code != (BPF_LD | BPF_IMM | BPF_DW)) {
> pr_warning("bpf: relocation: invalid relo for insns[%d].code 0x%x\n",
> insn_idx, insns[insn_idx].code);
> - return -EINVAL;
> + return -LIBBPF_ERRNO__ERELOC;
> }
>
> map_idx = sym.st_value / sizeof(struct bpf_map_def);
> if (map_idx >= nr_maps) {
> pr_warning("bpf relocation: map_idx %d large than %d\n",
> (int)map_idx, (int)nr_maps - 1);
> - return -EINVAL;
> + return -LIBBPF_ERRNO__ERELOC;
> }
>
> prog->reloc_desc[i].insn_idx = insn_idx;
> @@ -683,7 +740,7 @@ bpf_program__relocate(struct bpf_program *prog, int *map_fds)
> if (insn_idx >= (int)prog->insns_cnt) {
> pr_warning("relocation out of range: '%s'\n",
> prog->section_name);
> - return -ERANGE;
> + return -LIBBPF_ERRNO__ERELOC;
> }
> insns[insn_idx].src_reg = BPF_PSEUDO_MAP_FD;
> insns[insn_idx].imm = map_fds[map_idx];
> @@ -721,7 +778,7 @@ static int bpf_object__collect_reloc(struct bpf_object *obj)
>
> if (!obj_elf_valid(obj)) {
> pr_warning("Internal error: elf object is closed\n");
> - return -EINVAL;
> + return -LIBBPF_ERRNO__EINTERNAL;
> }
>
> for (i = 0; i < obj->efile.nr_reloc; i++) {
> @@ -734,21 +791,21 @@ static int bpf_object__collect_reloc(struct bpf_object *obj)
>
> if (shdr->sh_type != SHT_REL) {
> pr_warning("internal error at %d\n", __LINE__);
> - return -EINVAL;
> + return -LIBBPF_ERRNO__EINTERNAL;
> }
>
> prog = bpf_object__find_prog_by_idx(obj, idx);
> if (!prog) {
> pr_warning("relocation failed: no %d section\n",
> idx);
> - return -ENOENT;
> + return -LIBBPF_ERRNO__ERELOC;
> }
>
> err = bpf_program__collect_reloc(prog, nr_maps,
> shdr, data,
> obj->efile.symbols);
> if (err)
> - return -EINVAL;
> + return err;
> }
> return 0;
> }
> @@ -777,7 +834,7 @@ load_program(struct bpf_insn *insns, int insns_cnt,
> goto out;
> }
>
> - ret = -EINVAL;
> + ret = -LIBBPF_ERRNO__ELOAD;
> pr_warning("load bpf program failed: %s\n", strerror(errno));
>
> if (log_buf) {
> @@ -831,7 +888,7 @@ static int bpf_object__validate(struct bpf_object *obj)
> if (obj->kern_version == 0) {
> pr_warning("%s doesn't provide kernel version\n",
> obj->path);
> - return -EINVAL;
> + return -LIBBPF_ERRNO__EKVERSION;
> }
> return 0;
> }
> @@ -840,32 +897,28 @@ static struct bpf_object *
> __bpf_object__open(const char *path, void *obj_buf, size_t obj_buf_sz)
> {
> struct bpf_object *obj;
> + int err;
>
> if (elf_version(EV_CURRENT) == EV_NONE) {
> pr_warning("failed to init libelf for %s\n", path);
> - return NULL;
> + return ERR_PTR(-LIBBPF_ERRNO__ELIBELF);
> }
>
> obj = bpf_object__new(path, obj_buf, obj_buf_sz);
> - if (!obj)
> - return NULL;
> + if (IS_ERR(obj))
> + return obj;
>
> - if (bpf_object__elf_init(obj))
> - goto out;
> - if (bpf_object__check_endianness(obj))
> - goto out;
> - if (bpf_object__elf_collect(obj))
> - goto out;
> - if (bpf_object__collect_reloc(obj))
> - goto out;
> - if (bpf_object__validate(obj))
> - goto out;
> + CHECK_ERR(bpf_object__elf_init(obj), err, out);
> + CHECK_ERR(bpf_object__check_endianness(obj), err, out);
> + CHECK_ERR(bpf_object__elf_collect(obj), err, out);
> + CHECK_ERR(bpf_object__collect_reloc(obj), err, out);
> + CHECK_ERR(bpf_object__validate(obj), err, out);
>
> bpf_object__elf_finish(obj);
> return obj;
> out:
> bpf_object__close(obj);
> - return NULL;
> + return ERR_PTR(err);
> }
>
> struct bpf_object *bpf_object__open(const char *path)
> @@ -922,6 +975,8 @@ int bpf_object__unload(struct bpf_object *obj)
>
> int bpf_object__load(struct bpf_object *obj)
> {
> + int err;
> +
> if (!obj)
> return -EINVAL;
>
> @@ -931,18 +986,16 @@ int bpf_object__load(struct bpf_object *obj)
> }
>
> obj->loaded = true;
> - if (bpf_object__create_maps(obj))
> - goto out;
> - if (bpf_object__relocate(obj))
> - goto out;
> - if (bpf_object__load_progs(obj))
> - goto out;
> +
> + CHECK_ERR(bpf_object__create_maps(obj), err, out);
> + CHECK_ERR(bpf_object__relocate(obj), err, out);
> + CHECK_ERR(bpf_object__load_progs(obj), err, out);
>
> return 0;
> out:
> bpf_object__unload(obj);
> pr_warning("failed to load object '%s'\n", obj->path);
> - return -EINVAL;
> + return err;
> }
>
> void bpf_object__close(struct bpf_object *obj)
> @@ -990,7 +1043,7 @@ const char *
> bpf_object__get_name(struct bpf_object *obj)
> {
> if (!obj)
> - return NULL;
> + return ERR_PTR(-EINVAL);
> return obj->path;
> }
>
> @@ -1043,7 +1096,7 @@ const char *bpf_program__title(struct bpf_program *prog, bool dup)
> title = strdup(title);
> if (!title) {
> pr_warning("failed to strdup program title\n");
> - return NULL;
> + return ERR_PTR(-ENOMEM);
> }
> }
>
> diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
> index f16170c..c2606ae 100644
> --- a/tools/lib/bpf/libbpf.h
> +++ b/tools/lib/bpf/libbpf.h
> @@ -10,6 +10,18 @@
>
> #include <stdio.h>
> #include <stdbool.h>
> +#include <linux/err.h>
> +
> +#define LIBBPF_ERRNO__START 4000
> +#define LIBBPF_ERRNO__ELIBELF 4000 /* Something wrong in libelf */
> +#define LIBBPF_ERRNO__EFORMAT 4001 /* BPF object format invalid */
> +#define LIBBPF_ERRNO__EKVERSION 4002 /* Incorrect or no 'version' section */
> +#define LIBBPF_ERRNO__EENDIAN 4003 /* Endian missmatch */
> +#define LIBBPF_ERRNO__EINTERNAL 4004 /* Internal error in libbpf */
> +#define LIBBPF_ERRNO__ERELOC 4005 /* Relocation failed */
> +#define LIBBPF_ERRNO__ELOAD 4006 /* Failed to load program */
> +
> +int libbpf_strerror(int err, char *buf, size_t size);
>
> /*
> * In include/linux/compiler-gcc.h, __printf is defined. However
> diff --git a/tools/perf/tests/llvm.c b/tools/perf/tests/llvm.c
> index 512d362..8f713f6 100644
> --- a/tools/perf/tests/llvm.c
> +++ b/tools/perf/tests/llvm.c
> @@ -27,7 +27,7 @@ static int test__bpf_parsing(void *obj_buf, size_t obj_buf_sz)
> struct bpf_object *obj;
>
> obj = bpf_object__open_buffer(obj_buf, obj_buf_sz, NULL);
> - if (!obj)
> + if (IS_ERR(obj))
> return -1;
> bpf_object__close(obj);
> return 0;
> diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c
> index 0c5d174..76f07ce 100644
> --- a/tools/perf/util/bpf-loader.c
> +++ b/tools/perf/util/bpf-loader.c
> @@ -59,9 +59,9 @@ struct bpf_object *bpf__prepare_load(const char *filename, bool source)
> } else
> obj = bpf_object__open(filename);
>
> - if (!obj) {
> + if (IS_ERR(obj)) {
> pr_debug("bpf: failed to load %s\n", filename);
> - return ERR_PTR(-EINVAL);
> + return obj;
> }
>
> return obj;
> @@ -96,9 +96,9 @@ config_bpf_program(struct bpf_program *prog)
> int err;
>
> config_str = bpf_program__title(prog, false);
> - if (!config_str) {
> + if (IS_ERR(config_str)) {
> pr_debug("bpf: unable to get title for program\n");
> - return -EINVAL;
> + return PTR_ERR(config_str);
> }
>
> priv = calloc(sizeof(*priv), 1);
> diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
> index bee6058..c75b25d 100644
> --- a/tools/perf/util/parse-events.c
> +++ b/tools/perf/util/parse-events.c
> @@ -632,11 +632,11 @@ int parse_events_load_bpf(struct parse_events_evlist *data,
> struct bpf_object *obj;
>
> obj = bpf__prepare_load(bpf_file_name, source);
> - if (IS_ERR(obj) || !obj) {
> + if (IS_ERR(obj)) {
> char errbuf[BUFSIZ];
> int err;
>
> - err = obj ? PTR_ERR(obj) : -EINVAL;
> + err = PTR_ERR(obj);
>
> if (err == -ENOTSUP)
> snprintf(errbuf, sizeof(errbuf),
> --
> 1.8.3.4
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH v2 3/4] bpf tools: Improve libbpf error reporting
2015-11-04 22:01 ` Arnaldo Carvalho de Melo
@ 2015-11-05 1:48 ` Wangnan (F)
2015-11-05 2:07 ` Wangnan (F)
0 siblings, 1 reply; 8+ messages in thread
From: Wangnan (F) @ 2015-11-05 1:48 UTC (permalink / raw)
To: Arnaldo Carvalho de Melo; +Cc: namhyung, lizefan, pi3orama, linux-kernel
On 2015/11/5 6:01, Arnaldo Carvalho de Melo wrote:
> Em Wed, Nov 04, 2015 at 02:25:58AM +0000, Wang Nan escreveu:
>> In this patch, a series libbpf specific error numbers and
>> libbpf_strerror() are created to help reporting error to caller.
>> Functions are updated to pass correct error number through macro
>> CHECK_ERR().
>>
>> All users of bpf_object__open{_buffer}() and bpf_program__title()
>> in perf are modified accordingly.
> So, before I get:
>
> [root@zoo ~]# perf record -e /tmp/foo.o sleep 1
> event syntax error: '/tmp/foo.o'
> \___ Invalid argument: Are you root and runing a CONFIG_BPF_SYSCALL kernel?
>
> (add -v to see detail)
> Run 'perf list' for a list of valid events
>
> Usage: perf record [<options>] [<command>]
> or: perf record [<options>] -- <command> [<options>]
>
> -e, --event <event> event selector. use 'perf list' to list available events
>
>
> And now:
>
> [root@zoo ~]# perf record -e /tmp/foo.o sleep 1
> event syntax error: '/tmp/foo.o'
> \___ Unknown error 4006
>
> (add -v to see detail)
> Run 'perf list' for a list of valid events
>
> Usage: perf record [<options>] [<command>]
> or: perf record [<options>] -- <command> [<options>]
>
> -e, --event <event> event selector. use 'perf list' to list available events
> [root@zoo ~]#
>
> Can you please fix this? The relevant strerror() routine should know about the
> errors it handles and produce an informative message.
>
> - Arnaldo
>
An libbpf related patches are losted because yesterday I didn't know
your head.
Today I'd like to merge my two patchsets and send them to you together.
Thank you.
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH v2 3/4] bpf tools: Improve libbpf error reporting
2015-11-05 1:48 ` Wangnan (F)
@ 2015-11-05 2:07 ` Wangnan (F)
0 siblings, 0 replies; 8+ messages in thread
From: Wangnan (F) @ 2015-11-05 2:07 UTC (permalink / raw)
To: Arnaldo Carvalho de Melo; +Cc: namhyung, lizefan, pi3orama, linux-kernel
On 2015/11/5 9:48, Wangnan (F) wrote:
>
>
> On 2015/11/5 6:01, Arnaldo Carvalho de Melo wrote:
>> Em Wed, Nov 04, 2015 at 02:25:58AM +0000, Wang Nan escreveu:
>>> In this patch, a series libbpf specific error numbers and
>>> libbpf_strerror() are created to help reporting error to caller.
>>> Functions are updated to pass correct error number through macro
>>> CHECK_ERR().
>>>
>>> All users of bpf_object__open{_buffer}() and bpf_program__title()
>>> in perf are modified accordingly.
>> So, before I get:
>>
>> [root@zoo ~]# perf record -e /tmp/foo.o sleep 1
>> event syntax error: '/tmp/foo.o'
>> \___ Invalid argument: Are you root and
>> runing a CONFIG_BPF_SYSCALL kernel?
>>
>> (add -v to see detail)
>> Run 'perf list' for a list of valid events
>>
>> Usage: perf record [<options>] [<command>]
>> or: perf record [<options>] -- <command> [<options>]
>>
>> -e, --event <event> event selector. use 'perf list' to list
>> available events
>>
>>
>> And now:
>>
>> [root@zoo ~]# perf record -e /tmp/foo.o sleep 1
>> event syntax error: '/tmp/foo.o'
>> \___ Unknown error 4006
>>
>> (add -v to see detail)
>> Run 'perf list' for a list of valid events
>>
>> Usage: perf record [<options>] [<command>]
>> or: perf record [<options>] -- <command> [<options>]
>>
>> -e, --event <event> event selector. use 'perf list' to list
>> available events
>> [root@zoo ~]#
>>
>> Can you please fix this? The relevant strerror() routine should know
>> about the
>> errors it handles and produce an informative message.
>>
>> - Arnaldo
>>
>
> An libbpf related patches are losted because yesterday I didn't know
> your head.
>
Nothing losted...
You won't see this after 4/4. However, I can fix this "Unknown error 4006"
reporting in this patch.
Thank you.
^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH v2 4/4] perf tools: Improve BPF related error messages output
2015-11-04 2:25 [PATCH v2 0/4] perf bpf: Improve error code delivering and output Wang Nan
` (2 preceding siblings ...)
2015-11-04 2:25 ` [PATCH v2 3/4] bpf tools: Improve libbpf error reporting Wang Nan
@ 2015-11-04 2:25 ` Wang Nan
3 siblings, 0 replies; 8+ messages in thread
From: Wang Nan @ 2015-11-04 2:25 UTC (permalink / raw)
To: acme, namhyung
Cc: lizefan, pi3orama, linux-kernel, Wang Nan,
Arnaldo Carvalho de Melo
A series of bpf loader related error code is introduced to help error
delivering. Functions are improved to return those new error code.
Functions which return pointers are adjusted to encode error code into
return value using "ERR_PTR".
bpf_loader_strerror() are introduced to convert those error message to
string. It detected the value of error code and calls libbpf_strerror()
and strerror_r() accordingly, so caller don't need to consider checking
the range of error code. bpf__strerror_head() is updated so existing
strerror functions can support these error code automatically.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
---
tools/perf/util/bpf-loader.c | 98 +++++++++++++++++++++++++++++++++++++-----
tools/perf/util/bpf-loader.h | 18 ++++++++
tools/perf/util/parse-events.c | 7 +--
3 files changed, 110 insertions(+), 13 deletions(-)
diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c
index 76f07ce..375f254 100644
--- a/tools/perf/util/bpf-loader.c
+++ b/tools/perf/util/bpf-loader.c
@@ -14,6 +14,10 @@
#include "probe-finder.h" // for MAX_PROBES
#include "llvm-utils.h"
+#if BPF_LOADER_ERRNO__END >= LIBBPF_ERRNO__START
+# error Too many BPF loader error code
+#endif
+
#define DEFINE_PRINT_FN(name, level) \
static int libbpf_##name(const char *fmt, ...) \
{ \
@@ -53,7 +57,7 @@ struct bpf_object *bpf__prepare_load(const char *filename, bool source)
err = llvm__compile_bpf(filename, &obj_buf, &obj_buf_sz);
if (err)
- return ERR_PTR(err);
+ return ERR_PTR(-BPF_LOADER_ERRNO__ECOMPILE);
obj = bpf_object__open_buffer(obj_buf, obj_buf_sz, filename);
free(obj_buf);
} else
@@ -113,14 +117,14 @@ config_bpf_program(struct bpf_program *prog)
if (err < 0) {
pr_debug("bpf: '%s' is not a valid config string\n",
config_str);
- err = -EINVAL;
+ err = -BPF_LOADER_ERRNO__ECONFIG;
goto errout;
}
if (pev->group && strcmp(pev->group, PERF_BPF_PROBE_GROUP)) {
pr_debug("bpf: '%s': group for event is set and not '%s'.\n",
config_str, PERF_BPF_PROBE_GROUP);
- err = -EINVAL;
+ err = -BPF_LOADER_ERRNO__EGROUP;
goto errout;
} else if (!pev->group)
pev->group = strdup(PERF_BPF_PROBE_GROUP);
@@ -132,9 +136,9 @@ config_bpf_program(struct bpf_program *prog)
}
if (!pev->event) {
- pr_debug("bpf: '%s': event name is missing\n",
+ pr_debug("bpf: '%s': event name is missing. Section name should be 'key=value'\n",
config_str);
- err = -EINVAL;
+ err = -BPF_LOADER_ERRNO__EEVENTNAME;
goto errout;
}
pr_debug("bpf: config '%s' is ok\n", config_str);
@@ -285,7 +289,7 @@ int bpf__foreach_tev(struct bpf_object *obj,
(void **)&priv);
if (err || !priv) {
pr_debug("bpf: failed to get private field\n");
- return -EINVAL;
+ return -BPF_LOADER_ERRNO__EINTERNAL;
}
pev = &priv->pev;
@@ -308,13 +312,65 @@ int bpf__foreach_tev(struct bpf_object *obj,
return 0;
}
+#define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0]))
+
+struct {
+ int code;
+ const char *msg;
+} bpf_loader_strerror_table[] = {
+ {BPF_LOADER_ERRNO__ECONFIG, "Invalid config string"},
+ {BPF_LOADER_ERRNO__EGROUP, "Invalid group name"},
+ {BPF_LOADER_ERRNO__EEVENTNAME, "No event name found in config string"},
+ {BPF_LOADER_ERRNO__EINTERNAL, "BPF loader internal error"},
+ {BPF_LOADER_ERRNO__ECOMPILE, "Error when compiling BPF scriptlet"},
+};
+
+static int
+bpf_loader_strerror(int err, char *buf, size_t size)
+{
+ unsigned int i;
+
+ if (!buf || !size)
+ return -1;
+
+ err = err > 0 ? err : -err;
+
+ if (err > LIBBPF_ERRNO__START)
+ return libbpf_strerror(err, buf, size);
+
+ if (err < BPF_LOADER_ERRNO__START) {
+ char sbuf[STRERR_BUFSIZE], *msg;
+
+ msg = strerror_r(err, sbuf, sizeof(sbuf));
+ snprintf(buf, size, "%s", msg);
+ buf[size - 1] = '\0';
+ return 0;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(bpf_loader_strerror_table); i++) {
+ if (bpf_loader_strerror_table[i].code == err) {
+ const char *msg;
+
+ msg = bpf_loader_strerror_table[i].msg;
+ snprintf(buf, size, "%s", msg);
+ buf[size - 1] = '\0';
+ return 0;
+ }
+ }
+
+ snprintf(buf, size, "Unknown bpf loader error %d", err);
+ buf[size - 1] = '\0';
+ return -1;
+}
+
#define bpf__strerror_head(err, buf, size) \
char sbuf[STRERR_BUFSIZE], *emsg;\
if (!size)\
return 0;\
if (err < 0)\
err = -err;\
- emsg = strerror_r(err, sbuf, sizeof(sbuf));\
+ bpf_loader_strerror(err, sbuf, sizeof(sbuf));\
+ emsg = sbuf;\
switch (err) {\
default:\
scnprintf(buf, size, "%s", emsg);\
@@ -330,13 +386,34 @@ int bpf__foreach_tev(struct bpf_object *obj,
}\
buf[size - 1] = '\0';
+int bpf__strerror_prepare_load(const char *filename, bool source,
+ int err, char *buf, size_t size)
+{
+ size_t n;
+ int ret;
+
+ n = snprintf(buf, size, "Failed to load %s%s: ",
+ filename, source ? " from source" : "");
+ if (n >= size) {
+ buf[size - 1] = '\0';
+ return 0;
+ }
+ buf += n;
+ size -= n;
+
+ ret = bpf_loader_strerror(err, buf, size);
+ buf[size - 1] = '\0';
+ return ret;
+}
+
int bpf__strerror_probe(struct bpf_object *obj __maybe_unused,
int err, char *buf, size_t size)
{
bpf__strerror_head(err, buf, size);
bpf__strerror_entry(EEXIST, "Probe point exist. Try use 'perf probe -d \"*\"'");
- bpf__strerror_entry(EPERM, "You need to be root, and /proc/sys/kernel/kptr_restrict should be 0\n");
- bpf__strerror_entry(ENOENT, "You need to check probing points in BPF file\n");
+ bpf__strerror_entry(EACCES, "You need to be root");
+ bpf__strerror_entry(EPERM, "You need to be root, and /proc/sys/kernel/kptr_restrict should be 0");
+ bpf__strerror_entry(ENOENT, "You need to check probing points in BPF file");
bpf__strerror_end(buf, size);
return 0;
}
@@ -345,7 +422,8 @@ int bpf__strerror_load(struct bpf_object *obj __maybe_unused,
int err, char *buf, size_t size)
{
bpf__strerror_head(err, buf, size);
- bpf__strerror_entry(EINVAL, "%s: Are you root and runing a CONFIG_BPF_SYSCALL kernel?",
+ bpf__strerror_entry(LIBBPF_ERRNO__ELOAD,
+ "%s: Validate your program and check 'license'/'version' sections in your object",
emsg)
bpf__strerror_end(buf, size);
return 0;
diff --git a/tools/perf/util/bpf-loader.h b/tools/perf/util/bpf-loader.h
index ccd8d7f..490c78c 100644
--- a/tools/perf/util/bpf-loader.h
+++ b/tools/perf/util/bpf-loader.h
@@ -11,6 +11,14 @@
#include "probe-event.h"
#include "debug.h"
+#define BPF_LOADER_ERRNO__START 3900
+#define BPF_LOADER_ERRNO__ECONFIG 3900 /* Invalid config string */
+#define BPF_LOADER_ERRNO__EGROUP 3901 /* Invalid group name */
+#define BPF_LOADER_ERRNO__EEVENTNAME 3902 /* Event name is missing */
+#define BPF_LOADER_ERRNO__EINTERNAL 3903 /* BPF loader internal error */
+#define BPF_LOADER_ERRNO__ECOMPILE 3904 /* Error when compiling BPF scriptlet */
+#define BPF_LOADER_ERRNO__END 3905
+
struct bpf_object;
#define PERF_BPF_PROBE_GROUP "perf_bpf_probe"
@@ -19,6 +27,8 @@ typedef int (*bpf_prog_iter_callback_t)(struct probe_trace_event *tev,
#ifdef HAVE_LIBBPF_SUPPORT
struct bpf_object *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);
void bpf__clear(void);
@@ -67,6 +77,14 @@ __bpf_strerror(char *buf, size_t size)
return 0;
}
+int bpf__strerror_prepare_load(const char *filename __maybe_unused,
+ bool source __maybe_unused,
+ int err __maybe_unused,
+ char *buf, size_t size)
+{
+ return __bpf_strerror(buf, size);
+}
+
static inline int
bpf__strerror_probe(struct bpf_object *obj __maybe_unused,
int err __maybe_unused,
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index c75b25d..e48d9da 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -642,9 +642,10 @@ int parse_events_load_bpf(struct parse_events_evlist *data,
snprintf(errbuf, sizeof(errbuf),
"BPF support is not compiled");
else
- snprintf(errbuf, sizeof(errbuf),
- "BPF object file '%s' is invalid",
- bpf_file_name);
+ bpf__strerror_prepare_load(bpf_file_name,
+ source,
+ -err, errbuf,
+ sizeof(errbuf));
data->error->help = strdup("(add -v to see detail)");
data->error->str = strdup(errbuf);
--
1.8.3.4
^ permalink raw reply related [flat|nested] 8+ messages in thread