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Linux kernel
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Jaroslav reported errors from valgrind over perf python script:
# echo 0 > /sys/devices/system/cpu/cpu4/online
# valgrind ./test.py
==7524== Memcheck, a memory error detector
...
==7524== Command: ./test.py
==7524==
pid 7526 exited
==7524== Invalid read of size 8
==7524== at 0xCC2C2B3: perf_mmap__read_forward (evlist.c:780)
==7524== by 0xCC2A681: pyrf_evlist__read_on_cpu (python.c:959)
...
==7524== Address 0x65c4868 is 16 bytes after a block of size 459,36..
==7524== at 0x4C2B955: calloc (vg_replace_malloc.c:711)
==7524== by 0xCC2F484: zalloc (util.h:35)
==7524== by 0xCC2F484: perf_evlist__alloc_mmap (evlist.c:978)
...
The reason for this is in the python interface, that allows a script to
pass arbitrary cpu number, which is then used to access struct
perf_evlist::mmap array. That's obviously wrong and works only when if
all cpus are available and fails if some cpu is missing, like in the
example above.
This patch makes pyrf_evlist__read_on_cpu() search the evlist's maps
array for the proper map to access.
It's linear search at the moment. Based on the way how is the
read_on_cpu used, I don't think we need to be fast in here. But we
could add some hash in the middle to make it fast/er.
We don't allow python interface to set write_backward event attribute,
so it's safe to check only evlist's mmaps.
Reported-by: Jaroslav Škarvada <jskarvad@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Joe Mario <jmario@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180817114556.28000-3-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Store the real cpu number in 'struct perf_mmap', which will be used by
python interface that allows user to read a particular memory map for
given cpu.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jaroslav Škarvada <jskarvad@redhat.com>
Cc: Joe Mario <jmario@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180817114556.28000-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Having comp carrying the compression ID, we no longer need return the
extension. Removing it and updating the automated test.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180817094813.15086-14-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add implementation of the is_compressed callback for gzip.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180817094813.15086-13-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add implementation of the is_compressed callback for lzma.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180817094813.15086-12-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add is_compressed callback to the compressions array, that returns 0 if
the file is compressed or != 0 if not.
The new callback is used to recognize the situation when we have a
'compressed' object, like:
/lib/modules/.../drivers/net/ethernet/intel/igb/igb.ko.xz
but we need to read its debug data from debuginfo files, which might not
be compressed, like:
/root/.debug/.build-id/d6/...c4b301f/debug
So even for a 'compressed' object we read debug data from a plain
uncompressed object. To keep this transparent, we detect this in
decompress_kmodule() and return the file descriptor to the uncompressed
file.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180817094813.15086-11-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We will add a compression check in the following patch and it makes it
easier if the file processing is done in a single place. It also makes
the current code simpler.
The decompress_kmodule function now returns the fd of the uncompressed
file and the file name in the pathname arg, if it's provided.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180817094813.15086-10-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Once we parsed out the compression ID, we dont need to iterate all
available compressions and we can call it directly.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180817094813.15086-9-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add comp to 'struct dso' to hold the compression index. It will be used
in the following patches.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180817094813.15086-8-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Store a decompression ID in 'struct kmod_path', so it can be later
stored in 'struct dso'.
Switch 'struct kmod_path's 'comp' from 'bool' to 'int' to return the
compressions array index. Add 0 index item into compressions array, so
that the comp usage stays as it was: 0 - no compression, != 0
compression index.
Update the kmod_path tests.
Committer notes:
Use a designated initializer + terminating comma, e.g. { .fmt = NULL, }, to fix
the build in several distros:
centos:6: util/dso.c:201: error: missing initializer
centos:6: util/dso.c:201: error: (near initialization for 'compressions[0].decompress')
debian:9: util/dso.c:201:24: error: missing field 'decompress' initializer [-Werror,-Wmissing-field-initializers]
fedora:25: util/dso.c:201:24: error: missing field 'decompress' initializer [-Werror,-Wmissing-field-initializers]
fedora:26: util/dso.c:201:24: error: missing field 'decompress' initializer [-Werror,-Wmissing-field-initializers]
fedora:27: util/dso.c:201:24: error: missing field 'decompress' initializer [-Werror,-Wmissing-field-initializers]
oraclelinux:6: util/dso.c:201: error: missing initializer
oraclelinux:6: util/dso.c:201: error: (near initialization for 'compressions[0].decompress')
ubuntu:12.04.5: util/dso.c:201:2: error: missing initializer [-Werror=missing-field-initializers]
ubuntu:12.04.5: util/dso.c:201:2: error: (near initialization for 'compressions[0].decompress') [-Werror=missing-field-initializers]
ubuntu:16.04: util/dso.c:201:24: error: missing field 'decompress' initializer [-Werror,-Wmissing-field-initializers]
ubuntu:16.10: util/dso.c:201:24: error: missing field 'decompress' initializer [-Werror,-Wmissing-field-initializers]
ubuntu:16.10: util/dso.c:201:24: error: missing field 'decompress' initializer [-Werror,-Wmissing-field-initializers]
ubuntu:17.10: util/dso.c:201:24: error: missing field 'decompress' initializer [-Werror,-Wmissing-field-initializers]
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180817094813.15086-7-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There's no outside user of it.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180817094813.15086-6-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There's no outside user of it.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180817094813.15086-5-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There's no need to call dso__needs_decompress() twice in the function.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180817094813.15086-4-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There's no need to call dso__needs_decompress() twice in the function.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180817094813.15086-3-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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