Perf tool fails to unwind user stack if the event raises in a shared
object. This patch improves tests/dwarf-unwind.c to demonstrate the
problem by utilizing commonly used glibc function "bsearch". If perf is
not statically linked, the testcase will try to unwind a mixed call
trace.
By debugging libunwind I found that there is a bug in unwind-libunwind:
it always passes 0 as segbase to libunwind, cause libunwind unable to
locate debug_frame entry fir first level ip address (I add some more
debugging output into libunwind to make things clear):
>_Uarm_dwarf_find_debug_frame: start_ip = 10be98, end_ip = 10c2a4
>_Uarm_dwarf_find_debug_frame: found debug_frame table `/lib/libc-2.18.so': segbase=0x0, len=7, gp=0x0, table_data=0x449388
>_Uarm_dwarf_search_unwind_table: call lookup:ip = b6cd3bcc, segbase = 0, rel_ip = b6cd3bcc
>lookup: e->start_ip_offset = bcf18 (rel_ip = b6cd3bcc)
>lookup: e->start_ip_offset = 6d314 (rel_ip = b6cd3bcc)
>lookup: e->start_ip_offset = 33d0c (rel_ip = b6cd3bcc)
...
>lookup: e->start_ip_offset = 15d0c (rel_ip = b6cd3bcc)
>lookup: e->start_ip_offset = 15c40 (rel_ip = b6cd3bcc)
>_Uarm_dwarf_search_unwind_table: IP b6cd3bcc inside range b6c12000-b6d4c000, but no explicit unwind info found
>put_rs_cache: unmasking signals/interrupts and releasing lock
>_Uarm_dwarf_step: returning -10
>_Uarm_step: dwarf_step()=-10
This patch passes map->start as segbase to dwarf_find_debug_frame(), so
di will be initialized correctly.
In addition, dso and executable are different when setting segbase. This
patch first check whether the elf is executable, and pass segbase only
for shared object.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1421203007-75799-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The unwind__get_entries() already receives the thread parameter, from where it can
obtain the matching machine structure, shorten the signature.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-isjc6bm8mv4612mhi6af64go@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Normally the callchain_param.record_mode is used only for record path.
But as it might need to prepare something for dwarf unwinding, setup
this info for perf report too.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1412556363-26229-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This reverts commit 3090ffb5a2.
Re-enable the mmap2 interface as we will have a user soon.
Since things have changed since perf disabled mmap2, small tweaks
to the revert had to be done:
o commit 9d4ecc88 forced (n!=8) to become (n<7)
o a new libunwind test needed updating to use mmap2 interface
Signed-off-by: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/r/1401461382-209586-1-git-send-email-dzickus@redhat.com
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Combine all definitions into a common tools/include/linux/types.h and
kill the wild growth elsewhere. Move DECLARE_BITMAP to its proper
bitmap.h header.
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Link: http://lkml.kernel.org/n/tip-azczs7qcv6h9xek9od10hiv2@git.kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Forcing the code to always search thread by pid/tid pair.
The PID value will be needed in future to determine the process thread
leader for map groups sharing.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1394805606-25883-3-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding mask info into struct regs_dump to make the registers information
compact.
The mask was always passed along, so logically the mask info fits more
into the struct regs_dump.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Jean Pihet <jean.pihet@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1389098853-14466-9-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding dwarf unwind test, that setups live machine data over the perf
test thread and does the remote unwind.
At this moment this test fails due to bug in the max_stack processing in
unwind__get_entries function. This is fixed in following patch.
Need to use -fno-optimize-sibling-calls for test compilation, otherwise
'krava_*' function calls are optimized into jumps and ommited from the
stack unwind.
So far it's enabled only for x86.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Jean Pihet <jean.pihet@linaro.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1389098853-14466-6-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
