* [PATCH] perf callchain: separate eh/debug frame offset cache.
@ 2015-03-13 7:02 Wang Nan
2015-03-13 9:44 ` Namhyung Kim
2015-03-22 10:13 ` [tip:perf/core] perf callchain: Separate eh/ debug " tip-bot for Wang Nan
0 siblings, 2 replies; 6+ messages in thread
From: Wang Nan @ 2015-03-13 7:02 UTC (permalink / raw)
To: Namhyung Kim, Arnaldo Carvalho de Melo, Jiri Olsa,
linux-kernel@vger.kernel.org
Cc: Ingo Molnar, Li Zefan
Commit f1f13af99a90 ("perf callchain: Cache eh/debug frame offset for
dwarf unwind") introduces a cache for .debug_frame and .eh_frame_hdr.
Unfortunately, it makes them share a same cache (dso->frame_offset).
Which causes unwind failure on ARM:
$ perf test unwind
Test dwarf unwind: FAILED!
The reason is that, if a dso has '.debug_frame' but doesn't have
'.eh_frame_hdr' (like ARM), dso->frame_offset will be filled by offset
of '.debug_frame' during the first time calling of find_proc_info() ->
read_unwind_spec_debug_frame(), and be regarded to '.eh_frame_hdr' when
the second time calling of find_proc_info() ->
read_unwind_spec_eh_frame(), since '.eh_frame_hdr' is checked prior to
'.debug_frame'.
This patch solves the problem by creating two cache fields for
'.eh_frame_hdr' and '.debug_frame'.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
---
tools/perf/util/dso.h | 3 ++-
tools/perf/util/unwind-libunwind.c | 8 ++++----
2 files changed, 6 insertions(+), 5 deletions(-)
diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h
index ced9284..408c65f 100644
--- a/tools/perf/util/dso.h
+++ b/tools/perf/util/dso.h
@@ -139,7 +139,8 @@ struct dso {
u32 status_seen;
size_t file_size;
struct list_head open_entry;
- u64 frame_offset;
+ u64 debug_frame_offset;
+ u64 eh_frame_hdr_offset;
} data;
union { /* Tool specific area */
diff --git a/tools/perf/util/unwind-libunwind.c b/tools/perf/util/unwind-libunwind.c
index e3c40a5..7b09a44 100644
--- a/tools/perf/util/unwind-libunwind.c
+++ b/tools/perf/util/unwind-libunwind.c
@@ -266,7 +266,7 @@ static int read_unwind_spec_eh_frame(struct dso *dso, struct machine *machine,
u64 *fde_count)
{
int ret = -EINVAL, fd;
- u64 offset = dso->data.frame_offset;
+ u64 offset = dso->data.eh_frame_hdr_offset;
if (offset == 0) {
fd = dso__data_fd(dso, machine);
@@ -275,7 +275,7 @@ static int read_unwind_spec_eh_frame(struct dso *dso, struct machine *machine,
/* Check the .eh_frame section for unwinding info */
offset = elf_section_offset(fd, ".eh_frame_hdr");
- dso->data.frame_offset = offset;
+ dso->data.eh_frame_hdr_offset = offset;
}
if (offset)
@@ -291,7 +291,7 @@ static int read_unwind_spec_debug_frame(struct dso *dso,
struct machine *machine, u64 *offset)
{
int fd;
- u64 ofs = dso->data.frame_offset;
+ u64 ofs = dso->data.debug_frame_offset;
if (ofs == 0) {
fd = dso__data_fd(dso, machine);
@@ -300,7 +300,7 @@ static int read_unwind_spec_debug_frame(struct dso *dso,
/* Check the .debug_frame section for unwinding info */
ofs = elf_section_offset(fd, ".debug_frame");
- dso->data.frame_offset = ofs;
+ dso->data.debug_frame_offset = ofs;
}
*offset = ofs;
--
1.8.3.4
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH] perf callchain: separate eh/debug frame offset cache.
2015-03-13 7:02 [PATCH] perf callchain: separate eh/debug frame offset cache Wang Nan
@ 2015-03-13 9:44 ` Namhyung Kim
2015-03-19 6:20 ` Wang Nan
2015-03-22 10:13 ` [tip:perf/core] perf callchain: Separate eh/ debug " tip-bot for Wang Nan
1 sibling, 1 reply; 6+ messages in thread
From: Namhyung Kim @ 2015-03-13 9:44 UTC (permalink / raw)
To: Wang Nan
Cc: Arnaldo Carvalho de Melo, Jiri Olsa, linux-kernel@vger.kernel.org,
Ingo Molnar, Li Zefan
Hi Wang,
On Fri, Mar 13, 2015 at 03:02:56PM +0800, Wang Nan wrote:
> Commit f1f13af99a90 ("perf callchain: Cache eh/debug frame offset for
> dwarf unwind") introduces a cache for .debug_frame and .eh_frame_hdr.
> Unfortunately, it makes them share a same cache (dso->frame_offset).
> Which causes unwind failure on ARM:
>
> $ perf test unwind
> Test dwarf unwind: FAILED!
>
> The reason is that, if a dso has '.debug_frame' but doesn't have
> '.eh_frame_hdr' (like ARM), dso->frame_offset will be filled by offset
> of '.debug_frame' during the first time calling of find_proc_info() ->
> read_unwind_spec_debug_frame(), and be regarded to '.eh_frame_hdr' when
> the second time calling of find_proc_info() ->
> read_unwind_spec_eh_frame(), since '.eh_frame_hdr' is checked prior to
> '.debug_frame'.
>
> This patch solves the problem by creating two cache fields for
> '.eh_frame_hdr' and '.debug_frame'.
>
> Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Thanks,
Namhyung
> ---
> tools/perf/util/dso.h | 3 ++-
> tools/perf/util/unwind-libunwind.c | 8 ++++----
> 2 files changed, 6 insertions(+), 5 deletions(-)
>
> diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h
> index ced9284..408c65f 100644
> --- a/tools/perf/util/dso.h
> +++ b/tools/perf/util/dso.h
> @@ -139,7 +139,8 @@ struct dso {
> u32 status_seen;
> size_t file_size;
> struct list_head open_entry;
> - u64 frame_offset;
> + u64 debug_frame_offset;
> + u64 eh_frame_hdr_offset;
> } data;
>
> union { /* Tool specific area */
> diff --git a/tools/perf/util/unwind-libunwind.c b/tools/perf/util/unwind-libunwind.c
> index e3c40a5..7b09a44 100644
> --- a/tools/perf/util/unwind-libunwind.c
> +++ b/tools/perf/util/unwind-libunwind.c
> @@ -266,7 +266,7 @@ static int read_unwind_spec_eh_frame(struct dso *dso, struct machine *machine,
> u64 *fde_count)
> {
> int ret = -EINVAL, fd;
> - u64 offset = dso->data.frame_offset;
> + u64 offset = dso->data.eh_frame_hdr_offset;
>
> if (offset == 0) {
> fd = dso__data_fd(dso, machine);
> @@ -275,7 +275,7 @@ static int read_unwind_spec_eh_frame(struct dso *dso, struct machine *machine,
>
> /* Check the .eh_frame section for unwinding info */
> offset = elf_section_offset(fd, ".eh_frame_hdr");
> - dso->data.frame_offset = offset;
> + dso->data.eh_frame_hdr_offset = offset;
> }
>
> if (offset)
> @@ -291,7 +291,7 @@ static int read_unwind_spec_debug_frame(struct dso *dso,
> struct machine *machine, u64 *offset)
> {
> int fd;
> - u64 ofs = dso->data.frame_offset;
> + u64 ofs = dso->data.debug_frame_offset;
>
> if (ofs == 0) {
> fd = dso__data_fd(dso, machine);
> @@ -300,7 +300,7 @@ static int read_unwind_spec_debug_frame(struct dso *dso,
>
> /* Check the .debug_frame section for unwinding info */
> ofs = elf_section_offset(fd, ".debug_frame");
> - dso->data.frame_offset = ofs;
> + dso->data.debug_frame_offset = ofs;
> }
>
> *offset = ofs;
> --
> 1.8.3.4
>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] perf callchain: separate eh/debug frame offset cache.
2015-03-13 9:44 ` Namhyung Kim
@ 2015-03-19 6:20 ` Wang Nan
2015-03-19 14:03 ` Arnaldo Carvalho de Melo
0 siblings, 1 reply; 6+ messages in thread
From: Wang Nan @ 2015-03-19 6:20 UTC (permalink / raw)
To: Ingo Molnar
Cc: Namhyung Kim, Arnaldo Carvalho de Melo, Jiri Olsa,
linux-kernel@vger.kernel.org, Li Zefan
Hi Ingo,
Could you please collect this patch? It fixes a bug which prevent unwind for ARM.
Thank you.
On 2015/3/13 17:44, Namhyung Kim wrote:
> Hi Wang,
>
> On Fri, Mar 13, 2015 at 03:02:56PM +0800, Wang Nan wrote:
>> Commit f1f13af99a90 ("perf callchain: Cache eh/debug frame offset for
>> dwarf unwind") introduces a cache for .debug_frame and .eh_frame_hdr.
>> Unfortunately, it makes them share a same cache (dso->frame_offset).
>> Which causes unwind failure on ARM:
>>
>> $ perf test unwind
>> Test dwarf unwind: FAILED!
>>
>> The reason is that, if a dso has '.debug_frame' but doesn't have
>> '.eh_frame_hdr' (like ARM), dso->frame_offset will be filled by offset
>> of '.debug_frame' during the first time calling of find_proc_info() ->
>> read_unwind_spec_debug_frame(), and be regarded to '.eh_frame_hdr' when
>> the second time calling of find_proc_info() ->
>> read_unwind_spec_eh_frame(), since '.eh_frame_hdr' is checked prior to
>> '.debug_frame'.
>>
>> This patch solves the problem by creating two cache fields for
>> '.eh_frame_hdr' and '.debug_frame'.
>>
>> Signed-off-by: Wang Nan <wangnan0@huawei.com>
>
> Acked-by: Namhyung Kim <namhyung@kernel.org>
>
> Thanks,
> Namhyung
>
>
>> ---
>> tools/perf/util/dso.h | 3 ++-
>> tools/perf/util/unwind-libunwind.c | 8 ++++----
>> 2 files changed, 6 insertions(+), 5 deletions(-)
>>
>> diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h
>> index ced9284..408c65f 100644
>> --- a/tools/perf/util/dso.h
>> +++ b/tools/perf/util/dso.h
>> @@ -139,7 +139,8 @@ struct dso {
>> u32 status_seen;
>> size_t file_size;
>> struct list_head open_entry;
>> - u64 frame_offset;
>> + u64 debug_frame_offset;
>> + u64 eh_frame_hdr_offset;
>> } data;
>>
>> union { /* Tool specific area */
>> diff --git a/tools/perf/util/unwind-libunwind.c b/tools/perf/util/unwind-libunwind.c
>> index e3c40a5..7b09a44 100644
>> --- a/tools/perf/util/unwind-libunwind.c
>> +++ b/tools/perf/util/unwind-libunwind.c
>> @@ -266,7 +266,7 @@ static int read_unwind_spec_eh_frame(struct dso *dso, struct machine *machine,
>> u64 *fde_count)
>> {
>> int ret = -EINVAL, fd;
>> - u64 offset = dso->data.frame_offset;
>> + u64 offset = dso->data.eh_frame_hdr_offset;
>>
>> if (offset == 0) {
>> fd = dso__data_fd(dso, machine);
>> @@ -275,7 +275,7 @@ static int read_unwind_spec_eh_frame(struct dso *dso, struct machine *machine,
>>
>> /* Check the .eh_frame section for unwinding info */
>> offset = elf_section_offset(fd, ".eh_frame_hdr");
>> - dso->data.frame_offset = offset;
>> + dso->data.eh_frame_hdr_offset = offset;
>> }
>>
>> if (offset)
>> @@ -291,7 +291,7 @@ static int read_unwind_spec_debug_frame(struct dso *dso,
>> struct machine *machine, u64 *offset)
>> {
>> int fd;
>> - u64 ofs = dso->data.frame_offset;
>> + u64 ofs = dso->data.debug_frame_offset;
>>
>> if (ofs == 0) {
>> fd = dso__data_fd(dso, machine);
>> @@ -300,7 +300,7 @@ static int read_unwind_spec_debug_frame(struct dso *dso,
>>
>> /* Check the .debug_frame section for unwinding info */
>> ofs = elf_section_offset(fd, ".debug_frame");
>> - dso->data.frame_offset = ofs;
>> + dso->data.debug_frame_offset = ofs;
>> }
>>
>> *offset = ofs;
>> --
>> 1.8.3.4
>>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] perf callchain: separate eh/debug frame offset cache.
2015-03-19 6:20 ` Wang Nan
@ 2015-03-19 14:03 ` Arnaldo Carvalho de Melo
2015-03-19 14:11 ` Jiri Olsa
0 siblings, 1 reply; 6+ messages in thread
From: Arnaldo Carvalho de Melo @ 2015-03-19 14:03 UTC (permalink / raw)
To: Jiri Olsa
Cc: Wang Nan, Ingo Molnar, Namhyung Kim, linux-kernel@vger.kernel.org,
Li Zefan
Em Thu, Mar 19, 2015 at 02:20:16PM +0800, Wang Nan escreveu:
> Hi Ingo,
>
>> Could you please collect this patch? It fixes a bug which prevent unwind for ARM.
Hi Jiri, can I have your Acked-by for this change, since you worked on
this unwind code the most?
- Arnaldo
>
> On 2015/3/13 17:44, Namhyung Kim wrote:
> > Hi Wang,
> >
> > On Fri, Mar 13, 2015 at 03:02:56PM +0800, Wang Nan wrote:
> >> Commit f1f13af99a90 ("perf callchain: Cache eh/debug frame offset for
> >> dwarf unwind") introduces a cache for .debug_frame and .eh_frame_hdr.
> >> Unfortunately, it makes them share a same cache (dso->frame_offset).
> >> Which causes unwind failure on ARM:
> >>
> >> $ perf test unwind
> >> Test dwarf unwind: FAILED!
> >>
> >> The reason is that, if a dso has '.debug_frame' but doesn't have
> >> '.eh_frame_hdr' (like ARM), dso->frame_offset will be filled by offset
> >> of '.debug_frame' during the first time calling of find_proc_info() ->
> >> read_unwind_spec_debug_frame(), and be regarded to '.eh_frame_hdr' when
> >> the second time calling of find_proc_info() ->
> >> read_unwind_spec_eh_frame(), since '.eh_frame_hdr' is checked prior to
> >> '.debug_frame'.
> >>
> >> This patch solves the problem by creating two cache fields for
> >> '.eh_frame_hdr' and '.debug_frame'.
> >>
> >> Signed-off-by: Wang Nan <wangnan0@huawei.com>
> >
> > Acked-by: Namhyung Kim <namhyung@kernel.org>
> >
> > Thanks,
> > Namhyung
> >
> >
> >> ---
> >> tools/perf/util/dso.h | 3 ++-
> >> tools/perf/util/unwind-libunwind.c | 8 ++++----
> >> 2 files changed, 6 insertions(+), 5 deletions(-)
> >>
> >> diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h
> >> index ced9284..408c65f 100644
> >> --- a/tools/perf/util/dso.h
> >> +++ b/tools/perf/util/dso.h
> >> @@ -139,7 +139,8 @@ struct dso {
> >> u32 status_seen;
> >> size_t file_size;
> >> struct list_head open_entry;
> >> - u64 frame_offset;
> >> + u64 debug_frame_offset;
> >> + u64 eh_frame_hdr_offset;
> >> } data;
> >>
> >> union { /* Tool specific area */
> >> diff --git a/tools/perf/util/unwind-libunwind.c b/tools/perf/util/unwind-libunwind.c
> >> index e3c40a5..7b09a44 100644
> >> --- a/tools/perf/util/unwind-libunwind.c
> >> +++ b/tools/perf/util/unwind-libunwind.c
> >> @@ -266,7 +266,7 @@ static int read_unwind_spec_eh_frame(struct dso *dso, struct machine *machine,
> >> u64 *fde_count)
> >> {
> >> int ret = -EINVAL, fd;
> >> - u64 offset = dso->data.frame_offset;
> >> + u64 offset = dso->data.eh_frame_hdr_offset;
> >>
> >> if (offset == 0) {
> >> fd = dso__data_fd(dso, machine);
> >> @@ -275,7 +275,7 @@ static int read_unwind_spec_eh_frame(struct dso *dso, struct machine *machine,
> >>
> >> /* Check the .eh_frame section for unwinding info */
> >> offset = elf_section_offset(fd, ".eh_frame_hdr");
> >> - dso->data.frame_offset = offset;
> >> + dso->data.eh_frame_hdr_offset = offset;
> >> }
> >>
> >> if (offset)
> >> @@ -291,7 +291,7 @@ static int read_unwind_spec_debug_frame(struct dso *dso,
> >> struct machine *machine, u64 *offset)
> >> {
> >> int fd;
> >> - u64 ofs = dso->data.frame_offset;
> >> + u64 ofs = dso->data.debug_frame_offset;
> >>
> >> if (ofs == 0) {
> >> fd = dso__data_fd(dso, machine);
> >> @@ -300,7 +300,7 @@ static int read_unwind_spec_debug_frame(struct dso *dso,
> >>
> >> /* Check the .debug_frame section for unwinding info */
> >> ofs = elf_section_offset(fd, ".debug_frame");
> >> - dso->data.frame_offset = ofs;
> >> + dso->data.debug_frame_offset = ofs;
> >> }
> >>
> >> *offset = ofs;
> >> --
> >> 1.8.3.4
> >>
>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] perf callchain: separate eh/debug frame offset cache.
2015-03-19 14:03 ` Arnaldo Carvalho de Melo
@ 2015-03-19 14:11 ` Jiri Olsa
0 siblings, 0 replies; 6+ messages in thread
From: Jiri Olsa @ 2015-03-19 14:11 UTC (permalink / raw)
To: Arnaldo Carvalho de Melo
Cc: Wang Nan, Ingo Molnar, Namhyung Kim, linux-kernel@vger.kernel.org,
Li Zefan
On Thu, Mar 19, 2015 at 11:03:52AM -0300, Arnaldo Carvalho de Melo wrote:
> Em Thu, Mar 19, 2015 at 02:20:16PM +0800, Wang Nan escreveu:
> > Hi Ingo,
> >
> >> Could you please collect this patch? It fixes a bug which prevent unwind for ARM.
>
> Hi Jiri, can I have your Acked-by for this change, since you worked on
> this unwind code the most?
yep, it's ok
Acked-by: Jiri Olsa <jolsa@kernel.org>
jirka
^ permalink raw reply [flat|nested] 6+ messages in thread
* [tip:perf/core] perf callchain: Separate eh/ debug frame offset cache.
2015-03-13 7:02 [PATCH] perf callchain: separate eh/debug frame offset cache Wang Nan
2015-03-13 9:44 ` Namhyung Kim
@ 2015-03-22 10:13 ` tip-bot for Wang Nan
1 sibling, 0 replies; 6+ messages in thread
From: tip-bot for Wang Nan @ 2015-03-22 10:13 UTC (permalink / raw)
To: linux-tip-commits
Cc: namhyung, linux-kernel, tglx, wangnan0, acme, lizefan, jolsa,
mingo, hpa
Commit-ID: 303cb89a6d708da9c24f6f3390ff68a2bd822a13
Gitweb: http://git.kernel.org/tip/303cb89a6d708da9c24f6f3390ff68a2bd822a13
Author: Wang Nan <wangnan0@huawei.com>
AuthorDate: Fri, 13 Mar 2015 15:02:56 +0800
Committer: Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Thu, 19 Mar 2015 13:53:27 -0300
perf callchain: Separate eh/debug frame offset cache.
Commit f1f13af99a90 ("perf callchain: Cache eh/debug frame offset for
dwarf unwind") introduces a cache for .debug_frame and .eh_frame_hdr.
Unfortunately, it makes them share a same cache (dso->frame_offset).
Which causes unwind failure on ARM:
$ perf test unwind
Test dwarf unwind: FAILED!
The reason is that, if a dso has '.debug_frame' but doesn't have
'.eh_frame_hdr' (like ARM), dso->frame_offset will be filled by offset
of '.debug_frame' during the first time calling of find_proc_info() ->
read_unwind_spec_debug_frame(), and be regarded to '.eh_frame_hdr' when
the second time calling of find_proc_info() ->
read_unwind_spec_eh_frame(), since '.eh_frame_hdr' is checked prior to
'.debug_frame'.
This patch solves the problem by creating two cache fields for
'.eh_frame_hdr' and '.debug_frame'.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/55028BA0.1030701@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/util/dso.h | 3 ++-
tools/perf/util/unwind-libunwind.c | 8 ++++----
2 files changed, 6 insertions(+), 5 deletions(-)
diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h
index ced9284..408c65f 100644
--- a/tools/perf/util/dso.h
+++ b/tools/perf/util/dso.h
@@ -139,7 +139,8 @@ struct dso {
u32 status_seen;
size_t file_size;
struct list_head open_entry;
- u64 frame_offset;
+ u64 debug_frame_offset;
+ u64 eh_frame_hdr_offset;
} data;
union { /* Tool specific area */
diff --git a/tools/perf/util/unwind-libunwind.c b/tools/perf/util/unwind-libunwind.c
index e3c40a5..7b09a44 100644
--- a/tools/perf/util/unwind-libunwind.c
+++ b/tools/perf/util/unwind-libunwind.c
@@ -266,7 +266,7 @@ static int read_unwind_spec_eh_frame(struct dso *dso, struct machine *machine,
u64 *fde_count)
{
int ret = -EINVAL, fd;
- u64 offset = dso->data.frame_offset;
+ u64 offset = dso->data.eh_frame_hdr_offset;
if (offset == 0) {
fd = dso__data_fd(dso, machine);
@@ -275,7 +275,7 @@ static int read_unwind_spec_eh_frame(struct dso *dso, struct machine *machine,
/* Check the .eh_frame section for unwinding info */
offset = elf_section_offset(fd, ".eh_frame_hdr");
- dso->data.frame_offset = offset;
+ dso->data.eh_frame_hdr_offset = offset;
}
if (offset)
@@ -291,7 +291,7 @@ static int read_unwind_spec_debug_frame(struct dso *dso,
struct machine *machine, u64 *offset)
{
int fd;
- u64 ofs = dso->data.frame_offset;
+ u64 ofs = dso->data.debug_frame_offset;
if (ofs == 0) {
fd = dso__data_fd(dso, machine);
@@ -300,7 +300,7 @@ static int read_unwind_spec_debug_frame(struct dso *dso,
/* Check the .debug_frame section for unwinding info */
ofs = elf_section_offset(fd, ".debug_frame");
- dso->data.frame_offset = ofs;
+ dso->data.debug_frame_offset = ofs;
}
*offset = ofs;
^ permalink raw reply related [flat|nested] 6+ messages in thread
end of thread, other threads:[~2015-03-22 10:13 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
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2015-03-13 7:02 [PATCH] perf callchain: separate eh/debug frame offset cache Wang Nan
2015-03-13 9:44 ` Namhyung Kim
2015-03-19 6:20 ` Wang Nan
2015-03-19 14:03 ` Arnaldo Carvalho de Melo
2015-03-19 14:11 ` Jiri Olsa
2015-03-22 10:13 ` [tip:perf/core] perf callchain: Separate eh/ debug " tip-bot for Wang Nan
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