Adding endianity swapping for event header attached via sample_id_all.
Currently we dont do that and it's causing wrong data to be read when
running report on architecture with different endianity than the record.
The perf is currently able to process 32-bit PPC samples on 32-bit
and 64-bit x86.
Together with other endianity patches, this change fixies perf report
discrepancies on origin and target systems as described in test 1
below, e.g. following perf report diff:
...
0.12% ps [kernel.kallsyms] [k] clear_page
- 0.12% awk bash [.] alloc_word_desc
+ 0.12% awk bash [.] yyparse
0.11% beah-rhts-task libpython2.6.so.1.0 [.] 0x5560e
0.10% perf libc-2.12.so [.] __ctype_toupper_loc
- 0.09% rhts-test-runne bash [.] maybe_make_export_env
+ 0.09% rhts-test-runne bash [.] 0x385a0
0.09% ps [kernel.kallsyms] [k] page_fault
...
Note, running following to test perf endianity handling:
test 1)
- origin system:
# perf record -a -- sleep 10 (any perf record will do)
# perf report > report.origin
# perf archive perf.data
- copy the perf.data, report.origin and perf.data.tar.bz2
to a target system and run:
# tar xjvf perf.data.tar.bz2 -C ~/.debug
# perf report > report.target
# diff -u report.origin report.target
- the diff should produce no output
(besides some white space stuff and possibly different
date/TZ output)
test 2)
- origin system:
# perf record -ag -fo /tmp/perf.data -- sleep 1
- mount origin system root to the target system on /mnt/origin
- target system:
# perf script --symfs /mnt/origin -I -i /mnt/origin/tmp/perf.data \
--kallsyms /mnt/origin/proc/kallsyms
- complete perf.data header is displayed
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Tested-by: David Ahern <dsahern@gmail.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338380624-7443-3-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
$ perf script -i /tmp/perf.data
...
gcc 13623 544315.062858: context-switches:
ffffffff815f65c9 __schedule ([kernel.kallsyms])
ffffffff81087cea __cond_resched ([kernel.kallsyms])
ffffffff815f6b92 _cond_resched ([kernel.kallsyms])
ffffffff815fb87a do_page_fault ([kernel.kallsyms])
ffffffff815f8465 page_fault ([kernel.kallsyms])
2b7a71ea0303 _dl_lookup_symbol_x ([kernel.kallsyms])
2b7a71ea1eb5 _dl_relocate_object ([kernel.kallsyms])
2b7a71e99b2e dl_main ([kernel.kallsyms])
2b7a71eab7f4 _dl_sysdep_start ([kernel.kallsyms])
All DSO's in a callchain are printed as [kernel.kallsyms].
git bisect chased it to:
547a92e0ae is the first bad commit
commit 547a92e0ae
Author: Akihiro Nagai <akihiro.nagai.hw@hitachi.com>
Date: Mon Jan 30 13:42:57 2012 +0900
perf script: Unify the expressions indicating "unknown"
The perf script command uses various expressions to indicate "unknown".
It is unfriendly for user scripts to parse it. So, this patch unifies
the expressions to "[unknown]".
Looks like a copy-paste in that the other references use al.map but this one
should be node->map.
With this patch you get:
$ perf script -i /tmp/perf.data
...
gcc 13623 544315.062858: context-switches:
ffffffff815f65c9 __schedule ([kernel.kallsyms])
ffffffff81087cea __cond_resched ([kernel.kallsyms])
ffffffff815f6b92 _cond_resched ([kernel.kallsyms])
ffffffff815fb87a do_page_fault ([kernel.kallsyms])
ffffffff815f8465 page_fault ([kernel.kallsyms])
2b7a71ea0303 _dl_lookup_symbol_x (/lib64/ld-2.14.90.so)
2b7a71ea1eb5 _dl_relocate_object (/lib64/ld-2.14.90.so)
2b7a71e99b2e dl_main (/lib64/ld-2.14.90.so)
2b7a71eab7f4 _dl_sysdep_start (/lib64/ld-2.14.90.so)
Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Akihiro Nagai <akihiro.nagai.hw@hitachi.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1338353906-60706-1-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In __perf_session__process_pipe_events(), there was a risk we would read
more than what a union perf_event struct can hold. this could happen in
case, perf is reading a file which contains new record types it does not
know about and which are larger than anything it knows about.
In general, perf is supposed to skip records it does not understand, but
in pipe mode, those have to be read and ignored. The fixed size header
contains the size of the record, but that size may be larger than union
perf_event, yet it was used as the backing to the read in:
union perf_event event;
void *p;
size = event->header.size;
p = &event;
p += sizeof(struct perf_event_header);
if (size - sizeof(struct perf_event_header)) {
err = readn(self->fd, p, size - sizeof(struct perf_event_header));
We fix this by allocating a buffer based on the size reported in the
header. We reuse the buffer as much as we can. We realloc in case it
becomes too small. In the common case, the performance impact is
negligible.
Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1337081295-10303-3-git-send-email-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When the perf data file is read cross architectures, the
perf_event__attr_swap function takes care about endianness of all the
struct fields except the bitfield flags.
The bitfield flags need to be transformed as well, since the bitfield
binary storage differs for both endians.
ABI says:
Bit-fields are allocated from right to left (least to most significant)
on little-endian implementations and from left to right (most to least
significant) on big-endian implementations.
The above seems to be byte specific, so we need to reverse each byte of
the bitfield. 'Internet' also says this might be implementation specific
and we probably need proper fix and carry perf_event_attr bitfield flags
in separate data file FEAT_ section. Thought this seems to work for now.
Note, running following to test perf endianity handling:
test 1)
- origin system:
# perf record -a -- sleep 10 (any perf record will do)
# perf report > report.origin
# perf archive perf.data
- copy the perf.data, report.origin and perf.data.tar.bz2
to a target system and run:
# tar xjvf perf.data.tar.bz2 -C ~/.debug
# perf report > report.target
# diff -u report.origin report.target
- the diff should produce no output
(besides some white space stuff and possibly different
date/TZ output)
test 2)
- origin system:
# perf record -ag -fo /tmp/perf.data -- sleep 1
- mount origin system root to the target system on /mnt/origin
- target system:
# perf script --symfs /mnt/origin -I -i /mnt/origin/tmp/perf.data \
--kallsyms /mnt/origin/proc/kallsyms
- complete perf.data header is displayed
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Tested-by: David Ahern <dsahern@gmail.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1337151548-2396-3-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fixes and improvements for perf/core:
- perf_target: abstraction for --uid, --pid, --tid, --cpu, --all-cpus handling,
eliminating code duplicated in the tools, having constraints that apply to
all of them, from Namhyung Kim
- Fixes for handling fallback to cpu-clock on PPC, from David Ahern
- Fix for processing events with unknown size, from Jiri Olsa
- Compilation fix on 32-bit, from Jiri Olsa
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The perf diff command is broken since:
perf hists: Threaded addition and sorting of entries
commit 1980c2ebd7
Several places were broken:
- hists data need to be collected into opened sessions instead
of into events
- session's hists data need to be initialized properly when the
session is created
- hist_entry__pcnt_snprintf: the percentage and displacement
buffer preparation must not use 'ret' because it's used
as a pointer to the final buffer
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120322133726.GB1601@m.brq.redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The default input file for perf report is not handled the same way as
perf record does it for its output file. This leads to unexpected
behavior of perf report, etc. E.g.:
# perf record -a -e cpu-cycles sleep 2 | perf report | cat
failed to open perf.data: No such file or directory (try 'perf record' first)
While perf record writes to a fifo, perf report expects perf.data to be
read. This patch changes this to accept fifos as input file.
Applies to the following commands:
perf annotate
perf buildid-list
perf evlist
perf kmem
perf lock
perf report
perf sched
perf script
perf timechart
Also fixes char const* -> const char* type declaration for filename
strings.
v2:
* Prevent potential null pointer access to input_name in
builtin-report.c. Needed due to removal of patch "perf report: Setup
browser if stdout is a pipe"
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1323248577-11268-5-git-send-email-robert.richter@amd.com
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>