Wang Nan [Mon, 4 Jul 2016 11:02:42 +0000 (11:02 +0000)]
tools lib bpf: Add license header
Adding a missing license descriptopn header to files in libbpf, make it
LGPL-2.1.
Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Eric Leblond <eleblond@stamus-networks.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1467630162-193121-1-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Jiri Olsa [Mon, 4 Jul 2016 12:16:23 +0000 (14:16 +0200)]
perf unwind: Call unwind__prepare_access for forked thread
Currently we call unwind__prepare_access for map event. In case we
report fork event the thread inherits its parent's maps and
unwind__prepare_access is never called for the thread.
This causes unwind__get_entries seeing uninitialized
unwind_libunwind_ops and thus returning no callchain.
Adding unwind__prepare_access calls for fork even processing.
Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1467634583-29147-5-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Jiri Olsa [Mon, 4 Jul 2016 12:16:22 +0000 (14:16 +0200)]
perf unwind: Add initialized arg into unwind__prepare_access
Adding initialized arg into unwind__prepare_access to get feedback about
the initialization state.
It's not possible to get it from error code, because we return 0 even in
case we don't recognize dso, which is valid.
The 'initialized' value is used in following patch to speedup
unwind__prepare_access calls logic in fork path.
Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1467634583-29147-4-git-send-email-jolsa@kernel.org
[ Remove ; after static inline function signatures, fixes build break ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Jiri Olsa [Mon, 4 Jul 2016 12:16:21 +0000 (14:16 +0200)]
perf tests: Fix hist accumulation test
User's values from .perfconfig could overload the default callchain
setup and cause this test to fail. Making sure the test is using
default callchain_param values.
Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1467634583-29147-3-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Jiri Olsa [Mon, 4 Jul 2016 12:16:20 +0000 (14:16 +0200)]
perf header: Transform nodes string info to struct
Storing NUMA info within struct numa_node instead of strings. This way
it's usable in future patches.
Also it turned out it's slightly less code involved than using strings.
Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1467634583-29147-2-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf buildid-cache: Scan and import user SDT events to probe cache
perf buildid-cache --add <binary> scans given binary and add
the SDT events to probe cache. "sdt_" prefix is appended for
all SDT providers to avoid event-name clash with other pre-defined
events. It is possible to use the cached SDT events as other cached
events, via perf probe --add "sdt_<provider>:<event>=<event>".
e.g.
----
# perf buildid-cache --add /lib/libc-2.17.so
# perf probe --cache --list | head -n 5
/usr/lib/libc-2.17.so (a6fb821bdf53660eb2c29f778757aef294d3d392):
sdt_libc:setjmp=setjmp
sdt_libc:longjmp=longjmp
sdt_libc:longjmp_target=longjmp_target
sdt_libc:memory_heap_new=memory_heap_new
# perf probe -x /usr/lib/libc-2.17.so \
-a sdt_libc:memory_heap_new=memory_heap_new
Added new event:
sdt_libc:memory_heap_new (on memory_heap_new
in /usr/lib/libc-2.17.so)
You can now use it in all perf tools, such as:
perf record -e sdt_libc:memory_heap_new -aR sleep 1
# perf probe -l
sdt_libc:memory_heap_new (on new_heap+183 in /usr/lib/libc-2.17.so)
----
Note that SDT event entries in probe-cache file is somewhat different
from normal cached events. Normal one starts with "#", but SDTs are
starting with "%".
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Hemant Kumar <hemant@linux.vnet.ibm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/146736025058.27797.13043265488541434502.stgit@devbox Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Allow user to set group name for adding new event. Note that user must
ensure that the group name doesn't conflict with existing group name
carefully.
E.g. Existing group name can conflict with other events. Especially,
using the group name reserved for kernel modules can hide kernel
embedded events when loading modules.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Hemant Kumar <hemant@linux.vnet.ibm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/146736024091.27797.9471545190066268995.stgit@devbox Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch serves the initial support to identify and list SDT events in
binaries. When programs containing SDT markers are compiled, gcc with
the help of assembler directives identifies them and places them in the
section ".note.stapsdt".
To find these markers from the binaries, one needs to traverse through
this section and parse the relevant details like the name, type and
location of the marker. Also, the original location could be skewed due
to the effect of prelinking. If that is the case, the locations need to
be adjusted.
The functions in this patch open a given ELF, find out the SDT section,
parse the relevant details, adjust the location (if necessary) and
populate them in a list.
A typical note entry in ".note.stapsdt" section is as follows :
The above shows an excerpt from the section ".note.stapsdt". 'nhdr' is
a structure which has the note name size (n_namesz), note description
size (n_desc_sz) and note type (n_type).
So, in order to parse the note note info, we need nhdr to tell us where
to start from. As can be seen from <sys/sdt.h>, the name of the SDT
notes given is "stapsdt". But this is not the identifier of the note.
After that, we go to description of the note to find out its location, the
address of the ".stapsdt.base" section and the semaphore address.
Then, we find the provider name and the SDT marker name and then follow the
arguments.
Signed-off-by: Hemant Kumar <hemant@linux.vnet.ibm.com> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/146736022628.27797.1201368329092908163.stgit@devbox Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf build: Add feature detection for libelf's elf_getshdrstrndx()
That appeared after 0.140, and will be used in the SDT code, so, to
avoid bisection break on older systems, add a feature detection and
provide a stub with a pr_debug() to keep it building.
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Hemant Kumar <hemant@linux.vnet.ibm.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-80y0eldgweorqnwha9rvfxjr@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
'perf probe --del' removes caches when '--cache' is given. Note that
the delete pattern is not the same as for normal events.
If you cached probes with event name, --del "eventname" works as
expected. However, if you skipped it, the cached probes doesn't have
actual event name. In that case --del "probe-desc" is required (wildcard
is acceptable). For example a cache entry has the probe-desc "vfs_read
$params", you can remove it with --del 'vfs_read*'.
Before analyzing debuginfo, try to find a corresponding entry from probe
cache always. This does not depend on --cache, the --cache enables to
store/update cache, but looking up the cache is always enabled.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Hemant Kumar <hemant@linux.vnet.ibm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/146736019226.27797.16366402884098398857.stgit@devbox Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1467113345-12669-4-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf trace beauty eventfd: No need to include eventfd.h
Old systems such as RHEL5 lack this file, and what we need is
already under ifdefs, so just ditch this #include.
Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-dzbjfllw6znuoy37skwnwa4r@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf trace beauty sched_policy: Define SCHED_RESET_ON_FORK for older systems
RHEL5 for instance doesn't have this one, help it.
Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-3adewnii78zi110eovfciopy@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf annotate: Add number of samples to the header
Staring at annotations of large functions is useless if there's only a
few samples in them. Report the number of samples in the header to make
this easier to determine.
Committer note:
The change amounts to:
- Percent | Source code & Disassembly of perf-vdso.so for cycles:u
------------------------------------------------------------------
+ Percent | Source code & Disassembly of perf-vdso.so for cycles:u (3278 samples)
+--------------------------------------------------------------------------------
Ravi Bangoria [Thu, 30 Jun 2016 06:14:19 +0000 (11:44 +0530)]
perf evsel: Utility function to fetch arch
Add Utility function to fetch arch using evsel. (evsel->env->arch)
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Anton Blanchard <anton@ozlabs.org> Cc: Daniel Axtens <dja@axtens.net> Cc: David Laight <David.Laight@ACULAB.COM> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/1467267262-4589-2-git-send-email-ravi.bangoria@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Colin King <colin.king@canonical.com> Acked-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: He Kuang <hekuang@huawei.com> Cc: Namhyung Kim <namhyung@kernel.org> Link: http://lkml.kernel.org/r/1467116617-8318-1-git-send-email-colin.king@canonical.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Andi Kleen [Fri, 24 Jun 2016 20:41:25 +0000 (13:41 -0700)]
perf tools: Add documentation for perf.data on disk format
Add some documentation for the on disk format of perf.data. This is not
documenting the actual perf events -- which are documented in
perf_event.h -- but just the additional headers that perf record adds
around them when writing the data to disk.
Wang Nan [Fri, 24 Jun 2016 11:22:11 +0000 (11:22 +0000)]
perf data ctf: Add '--all' option for 'perf data convert'
After this patch, 'perf data convert' convert comm events to output CTF
stream.
Result:
# perf record -a sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.378 MB perf.data (73 samples) ]
# perf data convert --to-ctf ./out.ctf
[ perf data convert: Converted 'perf.data' into CTF data './out.ctf' ]
[ perf data convert: Converted and wrote 0.003 MB (73 samples) ]
# perf data convert --all --to-ctf ./out.ctf
[ perf data convert: Converted 'perf.data' into CTF data './out.ctf' ]
[ perf data convert: Converted and wrote 0.023 MB (73 samples, 384 non-samples) ]
Wang Nan [Fri, 24 Jun 2016 11:22:09 +0000 (11:22 +0000)]
perf data ctf: Prepare collect non-sample events
Following commits are going to allow 'perf data convert' to collect not
only samples, but also non-sample events like comm and fork. In this
patch we count non-sample events using c.non_sample_count, and prepare
to print number of both type of events like:
# ~/perf data convert --all --to-ctf ./out.ctf
[ perf data convert: Converted 'perf.data' into CTF data './out.ctf' ]
[ perf data convert: Converted and wrote 0.846 MB (6508 samples, 686 non-samples) ]
Wang Nan [Fri, 24 Jun 2016 11:22:08 +0000 (11:22 +0000)]
perf data ctf: Add 'all' option
If 'all' option is selected, 'perf data convert' should convert not only
samples, but non-sample events such as comm and fork. Add this option in
perf_data_convert_opts. Following commits will add cmdline option to
select it.
Wang Nan [Fri, 24 Jun 2016 11:22:07 +0000 (11:22 +0000)]
perf data ctf: Pass convert options through opts structure
Following commits will add new option to 'perf data convert'. All options
should be grouped into a structure and passed to low level converter
(currently there's only one converter).
Introduce data-convert.h and define 'struct perf_data_convert_opts' in
it. Pass 'force' through opts.
Wang Nan [Fri, 24 Jun 2016 11:22:06 +0000 (11:22 +0000)]
perf data ctf: Add value_set_string() helper
There are many value_set_##x helper for integer, but only for integer.
This patch adds value_set_string() helper to help following commits
create string fields.
Jiri Olsa [Fri, 24 Jun 2016 12:40:25 +0000 (14:40 +0200)]
perf symbols: Use proper dso name for is_regular_file
Marc reported use of uninitialized memory:
> In commit "403567217d3f perf symbols: Do not read symbols/data from
> device files" a check to uninitialzied memory was added. This leads to
> the following valgrind output:
>
> ==24515== Syscall param stat(file_name) points to uninitialised byte(s)
> ==24515== at 0x75B26D5: _xstat (in /lib/x86_64-linux-gnu/libc-2.22.so)
> ==24515== by 0x4E548D: stat (stat.h:454)
> ==24515== by 0x4E548D: is_regular_file (util.c:687)
> ==24515== by 0x4A5BEE: dso__load (symbol.c:1435)
> ==24515== by 0x4BB1AE: map__load (map.c:289)
> ==24515== by 0x4BB1AE: map__find_symbol (map.c:333)
> ==24515== by 0x4835B3: thread__find_addr_location (event.c:1300)
> ==24515== by 0x4B5342: add_callchain_ip (machine.c:1652)
> ==24515== by 0x4B5342: thread__resolve_callchain_sample (machine.c:1906)
> ==24515== by 0x4B9E7D: thread__resolve_callchain (machine.c:1958)
> ==24515== by 0x441B3E: process_event (builtin-script.c:795)
> ==24515== by 0x441B3E: process_sample_event (builtin-script.c:920)
> ==24515== by 0x4BEE29: perf_evlist__deliver_sample (session.c:1192)
> ==24515== by 0x4BEE29: machines__deliver_event (session.c:1229)
> ==24515== by 0x4BF770: perf_session__deliver_event (session.c:1286)
> ==24515== by 0x4BF770: ordered_events__deliver_event (session.c:114)
> ==24515== by 0x4C1D17: __ordered_events__flush (ordered-events.c:207)
> ==24515== by 0x4C1D17: ordered_events__flush.part.3 (ordered-events.c:274)
> ==24515== by 0x4BF44C: perf_session__process_user_event (session.c:1325)
> ==24515== by 0x4BF44C: perf_session__process_event (session.c:1451)
> ==24515== Address 0x807c6a0 is 0 bytes inside a block of size 4,096 alloc'd
> ==24515== at 0x4C29C0F: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
> ==24515== by 0x4A5BCB: dso__load (symbol.c:1421)
> ==24515== by 0x4BB1AE: map__load (map.c:289)
> ==24515== by 0x4BB1AE: map__find_symbol (map.c:333)
> ==24515== by 0x4835B3: thread__find_addr_location (event.c:1300)
> ==24515== by 0x4B5342: add_callchain_ip (machine.c:1652)
> ==24515== by 0x4B5342: thread__resolve_callchain_sample (machine.c:1906)
> ==24515== by 0x4B9E7D: thread__resolve_callchain (machine.c:1958)
> ==24515== by 0x441B3E: process_event (builtin-script.c:795)
> ==24515== by 0x441B3E: process_sample_event (builtin-script.c:920)
> ==24515== by 0x4BEE29: perf_evlist__deliver_sample (session.c:1192)
> ==24515== by 0x4BEE29: machines__deliver_event (session.c:1229)
> ==24515== by 0x4BF770: perf_session__deliver_event (session.c:1286)
> ==24515== by 0x4BF770: ordered_events__deliver_event (session.c:114)
> ==24515== by 0x4C1D17: __ordered_events__flush (ordered-events.c:207)
> ==24515== by 0x4C1D17: ordered_events__flush.part.3 (ordered-events.c:274)
> ==24515== by 0x4BF44C: perf_session__process_user_event (session.c:1325)
> ==24515== by 0x4BF44C: perf_session__process_event (session.c:1451)
> ==24515== by 0x4C0EAC: __perf_session__process_events (session.c:1804)
> ==24515== by 0x4C0EAC: perf_session__process_events (session.c:1858)
The reason was a typo that passed global 'name' variable as the
is_regular_file argument instead dso->long_name.
Reported-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Wang Nan <wangnan0@huawei.com> Fixes: 403567217d3f ("perf symbols: Do not read symbols/data from device files") Link: http://lkml.kernel.org/r/1466772025-17471-2-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Wang Nan [Mon, 27 Jun 2016 10:24:05 +0000 (10:24 +0000)]
perf record: Prepare picking perf_event_mmap_page from multiple evlists
Following commits introduce new evlists to record. This patch adjusts
record__pick_pc() and introduces perf_evlist__pick_pc() to read control
page from one specific evlist. record__pick_pc() will be improved to
search control page from multiple evlists.
Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nilay Vaish <nilayvaish@gmail.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1467023052-146749-4-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Wang Nan [Mon, 27 Jun 2016 10:24:04 +0000 (10:24 +0000)]
perf record: Prepare reading from multiple evlists in record__mmap_read_all()
Following commits introduce new evlists to record. This patch adjusts
record__mmap_read_all() and record__mmap_read(): converting original
record__mmap_read_all() to record__mmap_read_evlist(), read from one
evlist; makes record__mmap_read() reading from specific evlist.
record__mmap_read_all() will be improved to read from multiple evlists.
Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nilay Vaish <nilayvaish@gmail.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1467023052-146749-3-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Wang Nan [Mon, 27 Jun 2016 10:24:03 +0000 (10:24 +0000)]
perf record: Move mmap setup block to separate function
Following commits introduce multiple evlists to record. This patch
extracts perf_evlist__mmap_ex() processing to a new function, creates
record__mmap() and record__mmap_evlist() to wrap perf_evlist__mmap_ex()
and its error processing. They will be improvemented to create mmap for
all evlists.
Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nilay Vaish <nilayvaish@gmail.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1467023052-146749-2-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Jiri Olsa [Fri, 24 Jun 2016 12:40:24 +0000 (14:40 +0200)]
perf data convert: Include config.h header
Otherwise some compiler might scream:
$ make LIBBABELTRACE_DIR=/opt/libbabeltrace/ LIBBABELTRACE=1
BUILD: Doing 'make -j4' parallel build
CC util/data-convert-bt.o
util/data-convert-bt.c: In function ‘convert__config’:
util/data-convert-bt.c:1299:19: error: implicit declaration of function ‘perf_config_u64’ [-Werror=implicit-function-declaration]
c->queue_size = perf_config_u64(var, value);
...
Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Marc Kleine-Budde <mkl@pengutronix.de> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Taeung Song <treeze.taeung@gmail.com> Cc: Wang Nan <wangnan0@huawei.com> Fixes: 41840d211c51 ("perf config: Move config declarations from util/cache.h to util/config.h") Link: http://lkml.kernel.org/r/1466772025-17471-1-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Wang Nan [Sat, 25 Jun 2016 01:41:58 +0000 (01:41 +0000)]
perf build: Add libbabeltrace to build-test
'make build-test' doesn't test LIBBABELTRACE=1. It misses a building
failure caused by commit 41840d211c51 ("perf config: Move config
declarations from util/cache.h to util/config.h"), breaks bisect.
I.e. it will find the right objdump from the environment data recorded
in the perf.data file + these triplets.
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Anton Blanchard <anton@ozlabs.org> Cc: Daniel Axtens <dja@axtens.net> Cc: Michael Ellerman <mpe@ellerman.id.au> Link: http://lkml.kernel.org/r/1466769240-12376-7-git-send-email-ravi.bangoria@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Naveen N. Rao [Fri, 24 Jun 2016 11:53:58 +0000 (17:23 +0530)]
perf annotate: Generalize handling of 'ret' instructions
Introduce helper to detect 'ret' instructions and use the same in the TUI.
A helper is needed since some architectures such as powerpc have more
than one return instruction.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Anton Blanchard <anton@ozlabs.org> Cc: Daniel Axtens <dja@axtens.net> Cc: Michael Ellerman <mpe@ellerman.id.au> Link: http://lkml.kernel.org/r/1466769240-12376-5-git-send-email-ravi.bangoria@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Ravi Bangoria [Fri, 24 Jun 2016 11:53:55 +0000 (17:23 +0530)]
perf annotate: Remove unused hist_entry__annotate function
hist_entry__annotate looks part of API but I don't find any caller
of this function. Removing it.
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Anton Blanchard <anton@ozlabs.org> Cc: Daniel Axtens <dja@axtens.net> Cc: Michael Ellerman <mpe@ellerman.id.au> Link: http://lkml.kernel.org/r/1466769240-12376-2-git-send-email-ravi.bangoria@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf/x86/intel: Add MSR_LAST_BRANCH_FROM_x quirk for ctx switch
Add quirk for context switch to save/restore the value of
MSR_LAST_BRANCH_FROM_x when LBR is enabled and there is potential for
kernel addresses to be in the lbr_from register.
To test this patch, use a perf tool and kernel with the patch
next in this series. That patch removes the work around that masked
the hw bug:
$ ./lbr_perf record --call-graph lbr -e cycles:k sleep 1
where lbr_perf is the patched perf tool, that allows to specify :k
on lbr mode. The above command will trigger a #GPF :
perf/x86/intel: Fix MSR_LAST_BRANCH_FROM_x bug when no TSX
Intel's SDM states that bits 61:62 in MSR_LAST_BRANCH_FROM_x are the
TSX flags for formats with LBR_TSX flags (i.e. LBR_FORMAT_EIP_EFLAGS2).
However, when the CPU has TSX support deactivated, bits 61:62 actually
behave as follows:
- For wrmsr(), bits 61:62 are considered part of the sign extension.
- When capturing branches, the LBR hw will always clear bits 61:62.
regardless of the sign extension.
Therefore, if:
1) LBR has TSX format.
2) CPU has no TSX support enabled.
... then any value passed to wrmsr() must be sign extended to 63 bits
and any value from rdmsr() must be converted to have a sign extension
of 61 bits, ignoring the values at TSX flags.
This bug was masked by the work-around to the Intel's CPU bug:
BJ94. "LBR May Contain Incorrect Information When Using FREEZE_LBRS_ON_PMI"
in Document Number: 324643-037US.
The aforementioned work-around uses hw flags to filter out all kernel
branches, limiting LBR callstack to user level execution only.
Since user addresses are not sign extended, they do not trigger the wrmsr()
bug in MSR_LAST_BRANCH_FROM_x when saved/restored at context switch.
Linus Torvalds [Sun, 26 Jun 2016 17:08:49 +0000 (10:08 -0700)]
Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"Two straightforward fixes.
One is a concurrency issue only affecting SAS connected SATA drives,
but which could hang the storage subsystem if it triggers (because the
outstanding command count on error never goes back to zero) and the
other is a NO_TAG fallout from the switch to hostwide tags which
causes the system to crash on module insertion (we've checked
carefully and only the 53c700 family of drivers is vulnerable to this
issue)"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
53c700: fix BUG on untagged commands
scsi: fix race between simultaneous decrements of ->host_failed
Ingo Molnar [Sun, 26 Jun 2016 10:41:59 +0000 (12:41 +0200)]
Merge tag 'perf-core-for-mingo-20160623' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
New features:
- Add 'callindent' option to 'perf script -F', to indent the Intel PT
call stack, making this output more ftrace-like (Adrian Hunter, Andi Kleen)
User visible changes:
- Enlarge 'pid' column width, to cope with large pids (Jiri Olsa)
Infrastructure changes:
- Fix cross platform unwind (He Kuang)
- Make destructors accept NULL, behaving like free() (Arnaldo Carvalho de Melo)
- Remove reference to perl interpreted in the recently added 'perf script'
stackcollapse python script (Arnaldo Carvalho de Melo)
- Rename CLASS__for_each() macros to CLASS__for_each_entry(), to use the
list_for_each_entry() semantics, as most of these class specific loop helpers
are list_for_each_entry*() wrappers (Arnaldo Carvalho de Melo)
- Expose the hist_browser code, will be used with data structures other
than perf_evsel (Jiri Olsa)
- Refactor 'perf config' (Taeung Song)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
Linus Torvalds [Sat, 25 Jun 2016 15:53:38 +0000 (08:53 -0700)]
Merge branch 'for-linus-4.7-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes part 2 from Chris Mason:
"This has one patch from Omar to bring iterate_shared back to btrfs.
We have a tree of work we queue up for directory items and it doesn't
lend itself well to shared access. While we're cleaning it up, Omar
has changed things to use an exclusive lock when there are delayed
items"
* 'for-linus-4.7-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix ->iterate_shared() by upgrading i_rwsem for delayed nodes
Linus Torvalds [Sat, 25 Jun 2016 15:42:31 +0000 (08:42 -0700)]
Merge branch 'for-linus-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
"I have a two part pull this time because one of the patches Dave
Sterba collected needed to be against v4.7-rc2 or higher (we used
rc4). I try to make my for-linus-xx branch testable on top of the
last major so we can hand fixes to people on the list more easily, so
I've split this pull in two.
This first part has some fixes and two performance improvements that
we've been testing for some time.
Josef's two performance fixes are most notable. The transid tracking
patch makes a big improvement on pretty much every workload"
* 'for-linus-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: Force stripesize to the value of sectorsize
btrfs: fix disk_i_size update bug when fallocate() fails
Btrfs: fix error handling in map_private_extent_buffer
Btrfs: fix error return code in btrfs_init_test_fs()
Btrfs: don't do nocow check unless we have to
btrfs: fix deadlock in delayed_ref_async_start
Btrfs: track transid for delayed ref flushing
Linus Torvalds [Sat, 25 Jun 2016 13:55:48 +0000 (06:55 -0700)]
Merge tag 'sound-4.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"Again pretty calm weeks: we've had only a few trivial / stable
HD-audio fixes in addition to a possible race fix for snd-dummy driver
spotted by syzkaller"
* tag 'sound-4.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: dummy: Fix a use-after-free at closing
ALSA: hda / realtek - add two more Thinkpad IDs (5050,5053) for tpt460 fixup
ALSA: hda - Fix the headset mic jack detection on Dell machine
ALSA: hda/tegra: iomem fixups for sparse warnings
ALSA: hdac_regmap - fix the register access for runtime PM
Linus Torvalds [Sat, 25 Jun 2016 13:38:42 +0000 (06:38 -0700)]
Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Thomas Gleixner:
"A couple of scheduler fixes:
- force watchdog reset while processing sysrq-w
- fix a deadlock when enabling trace events in the scheduler
- fixes to the throttled next buddy logic
- fixes for the average accounting (missing serialization and
underflow handling)
- allow kernel threads for fallback to online but not active cpus"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/core: Allow kthreads to fall back to online && !active cpus
sched/fair: Do not announce throttled next buddy in dequeue_task_fair()
sched/fair: Initialize throttle_count for new task-groups lazily
sched/fair: Fix cfs_rq avg tracking underflow
kernel/sysrq, watchdog, sched/core: Reset watchdog on all CPUs while processing sysrq-w
sched/debug: Fix deadlock when enabling sched events
sched/fair: Fix post_init_entity_util_avg() serialization
Omar Sandoval [Fri, 20 May 2016 20:50:33 +0000 (13:50 -0700)]
Btrfs: fix ->iterate_shared() by upgrading i_rwsem for delayed nodes
Commit fe742fd4f90f ("Revert "btrfs: switch to ->iterate_shared()"")
backed out the conversion to ->iterate_shared() for Btrfs because the
delayed inode handling in btrfs_real_readdir() is racy. However, we can
still do readdir in parallel if there are no delayed nodes.
This is a temporary fix which upgrades the shared inode lock to an
exclusive lock only when we have delayed items until we come up with a
more complete solution. While we're here, rename the
btrfs_{get,put}_delayed_items functions to make it very clear that
they're just for readdir.
Tested with xfstests and by doing a parallel kernel build:
while make tinyconfig && make -j4 && git clean dqfx; do
:
done
along with a bunch of parallel finds in another shell:
while true; do
for ((i=0; i<4; i++)); do
find . >/dev/null &
done
wait
done
Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Chris Mason <clm@fb.com>
Linus Torvalds [Sat, 25 Jun 2016 13:01:48 +0000 (06:01 -0700)]
Merge tag 'powerpc-4.7-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
"mm/radix (Aneesh Kumar K.V):
- Update to tlb functions ric argument
- Flush page walk cache when freeing page table
- Update Radix tree size as per ISA 3.0
mm/hash (Aneesh Kumar K.V):
- Use the correct PPP mask when updating HPTE
- Don't add memory coherence if cache inhibited is set
eeh (Gavin Shan):
- Fix invalid cached PE primary bus
bpf/jit (Naveen N. Rao):
- Disable classic BPF JIT on ppc64le
.. and fix faults caused by radix patching of SLB miss handler
(Michael Ellerman)"
* tag 'powerpc-4.7-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/bpf/jit: Disable classic BPF JIT on ppc64le
powerpc: Fix faults caused by radix patching of SLB miss handler
powerpc/eeh: Fix invalid cached PE primary bus
powerpc/mm/radix: Update Radix tree size as per ISA 3.0
powerpc/mm/hash: Don't add memory coherence if cache inhibited is set
powerpc/mm/hash: Use the correct PPP mask when updating HPTE
powerpc/mm/radix: Flush page walk cache when freeing page table
powerpc/mm/radix: Update to tlb functions ric argument
Michael Ellerman [Sat, 25 Jun 2016 11:53:30 +0000 (21:53 +1000)]
Fix build break in fork.c when THREAD_SIZE < PAGE_SIZE
Commit b235beea9e99 ("Clarify naming of thread info/stack allocators")
breaks the build on some powerpc configs, where THREAD_SIZE < PAGE_SIZE:
kernel/fork.c:235:2: error: implicit declaration of function 'free_thread_stack'
kernel/fork.c:355:8: error: assignment from incompatible pointer type
stack = alloc_thread_stack_node(tsk, node);
^
Fix it by renaming free_stack() to free_thread_stack(), and updating the
return type of alloc_thread_stack_node().
Fixes: b235beea9e99 ("Clarify naming of thread info/stack allocators") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Sat, 25 Jun 2016 02:08:33 +0000 (19:08 -0700)]
Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
"Two weeks worth of fixes here"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (41 commits)
init/main.c: fix initcall_blacklisted on ia64, ppc64 and parisc64
autofs: don't get stuck in a loop if vfs_write() returns an error
mm/page_owner: avoid null pointer dereference
tools/vm/slabinfo: fix spelling mistake: "Ocurrences" -> "Occurrences"
fs/nilfs2: fix potential underflow in call to crc32_le
oom, suspend: fix oom_reaper vs. oom_killer_disable race
ocfs2: disable BUG assertions in reading blocks
mm, compaction: abort free scanner if split fails
mm: prevent KASAN false positives in kmemleak
mm/hugetlb: clear compound_mapcount when freeing gigantic pages
mm/swap.c: flush lru pvecs on compound page arrival
memcg: css_alloc should return an ERR_PTR value on error
memcg: mem_cgroup_migrate() may be called with irq disabled
hugetlb: fix nr_pmds accounting with shared page tables
Revert "mm: disable fault around on emulated access bit architecture"
Revert "mm: make faultaround produce old ptes"
mailmap: add Boris Brezillon's email
mailmap: add Antoine Tenart's email
mm, sl[au]b: add __GFP_ATOMIC to the GFP reclaim mask
mm: mempool: kasan: don't poot mempool objects in quarantine
...
Linus Torvalds [Sat, 25 Jun 2016 01:52:31 +0000 (18:52 -0700)]
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma
Pull rdma fixes from Doug Ledford:
"This is the second batch of queued up rdma patches for this rc cycle.
There isn't anything really major in here. It's passed 0day,
linux-next, and local testing across a wide variety of hardware.
There are still a few known issues to be tracked down, but this should
amount to the vast majority of the rdma RC fixes.
Round two of 4.7 rc fixes:
- A couple minor fixes to the rdma core
- Multiple minor fixes to hfi1
- Multiple minor fixes to mlx4/mlx4
- A few minor fixes to i40iw"
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma: (31 commits)
IB/srpt: Reduce QP buffer size
i40iw: Enable level-1 PBL for fast memory registration
i40iw: Return correct max_fast_reg_page_list_len
i40iw: Correct status check on i40iw_get_pble
i40iw: Correct CQ arming
IB/rdmavt: Correct qp_priv_alloc() return value test
IB/hfi1: Don't zero out qp->s_ack_queue in rvt_reset_qp
IB/hfi1: Fix deadlock with txreq allocation slow path
IB/mlx4: Prevent cross page boundary allocation
IB/mlx4: Fix memory leak if QP creation failed
IB/mlx4: Verify port number in flow steering create flow
IB/mlx4: Fix error flow when sending mads under SRIOV
IB/mlx4: Fix the SQ size of an RC QP
IB/mlx5: Fix wrong naming of port_rcv_data counter
IB/mlx5: Fix post send fence logic
IB/uverbs: Initialize ib_qp_init_attr with zeros
IB/core: Fix false search of the IB_SA_WELL_KNOWN_GUID
IB/core: Fix RoCE v1 multicast join logic issue
IB/core: Fix no default GIDs when netdevice reregisters
IB/hfi1: Send a pkey change event on driver pkey update
...
Linus Torvalds [Sat, 25 Jun 2016 01:36:15 +0000 (18:36 -0700)]
Merge tag 'hwmon-for-linus-v4.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging
Pull hwmon fix from Guenter Roeck:
"Improve fan type detection for dell-smm to prevent kernel hang"
* tag 'hwmon-for-linus-v4.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
hwmon: (dell-smm) Cache fan_type() calls and change fan detection
Linus Torvalds [Sat, 25 Jun 2016 01:29:55 +0000 (18:29 -0700)]
Merge tag 'acpi-4.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI fix from Rafael Wysocki:
"Stable-candidate fix for a deadlock in ACPICA introduced during the
4.5 development cycle by a commit attempting to improve the handling
of AML code that doesn't belong to any namespace objects in a given
definition block (Lv Zheng)"
* tag 'acpi-4.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPICA: Namespace: Fix deadlock triggered by MLC support in dynamic table loading
Linus Torvalds [Sat, 25 Jun 2016 01:03:22 +0000 (18:03 -0700)]
Merge tag 'pm-4.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
"Fix for a latent cpufreq driver bug uncovered by a recent ACPICA
change and several fixes for the devfreq framework, including one fix
for an issue introduced recently.
Specifics:
- Fix a latent initialization issue in the pcc-cpufreq driver
(incorrect initial value of a structure field) that has been
uncovered by a recent ACPICA commit (Mike Galbraith).
- Add a missing notification in an update_devfreq() error code path
forgotten by a recent devfreq commit (Chanwoo Choi).
- Fix devfreq device frequency initialization (Lukasz Luba).
- Fix an incorrect IS_ERR() check in the devfreq framework discovered
by the Smatch checker (Dan Carpenter).
- Drop two excessive put_device() calls from the devfreq framework
(MyungJoo Ham, Cai Zhiyong).
- Fix a possible memory leak in the devfreq framework and drop an
unnecessary kfree() invocation from it (MyungJoo Ham)"
* tag 'pm-4.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / devfreq: Send the DEVFREQ_POSTCHANGE notification when target() is failed
cpufreq: pcc-cpufreq: Fix doorbell.access_width
PM / devfreq: fix initialization of current frequency in last status
PM / devfreq: exynos-nocp: Remove incorrect IS_ERR() check
PM / devfreq: remove double put_device
PM / devfreq: fix double call put_device
PM / devfreq: fix duplicated kfree on devfreq pointer
PM / devfreq: devm_kzalloc to have dev pointer more precisely
Linus Torvalds [Sat, 25 Jun 2016 00:51:14 +0000 (17:51 -0700)]
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon:
"Here are a few more arm64 fixes, but things do finally appear to be
slowing down. The main fix is avoiding hibernation in a previously
unanticipated situation where we have CPUs parked in the kernel, but
it's all good stuff.
- Fix icache/dcache sync for anonymous pages under migration
- Correct the ASID limit check
- Fix parallel builds of Image and Image.gz
- Refuse to hibernate when we have CPUs that we can't offline"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: hibernate: Don't hibernate on systems with stuck CPUs
arm64: smp: Add function to determine if cpus are stuck in the kernel
arm64: mm: remove page_mapping check in __sync_icache_dcache
arm64: fix boot image dependencies to not generate invalid images
arm64: update ASID limit
Rasmus Villemoes [Fri, 24 Jun 2016 21:50:30 +0000 (14:50 -0700)]
init/main.c: fix initcall_blacklisted on ia64, ppc64 and parisc64
When I replaced kasprintf("%pf") with a direct call to
sprint_symbol_no_offset I must have broken the initcall blacklisting
feature on the arches where dereference_function_descriptor() is
non-trivial.
Fixes: c8cdd2be213f (init/main.c: simplify initcall_blacklisted()) Link: http://lkml.kernel.org/r/1466027283-4065-1-git-send-email-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Yang Shi <yang.shi@linaro.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Petr Mladek <pmladek@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sudip Mukherjee [Fri, 24 Jun 2016 21:50:24 +0000 (14:50 -0700)]
mm/page_owner: avoid null pointer dereference
We have dereferenced page_ext before checking it. Lets check it first
and then used it.
Fixes: f86e4271978b ("mm: check the return value of lookup_page_ext for all call sites") Link: http://lkml.kernel.org/r/1465249059-7883-1-git-send-email-sudipm.mukherjee@gmail.com Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Torsten Hilbrich [Fri, 24 Jun 2016 21:50:18 +0000 (14:50 -0700)]
fs/nilfs2: fix potential underflow in call to crc32_le
The value `bytes' comes from the filesystem which is about to be
mounted. We cannot trust that the value is always in the range we
expect it to be.
Check its value before using it to calculate the length for the crc32_le
call. It value must be larger (or equal) sumoff + 4.
This fixes a kernel bug when accidentially mounting an image file which
had the nilfs2 magic value 0x3434 at the right offset 0x406 by chance.
The bytes 0x01 0x00 were stored at 0x408 and were interpreted as a
s_bytes value of 1. This caused an underflow when substracting sumoff +
4 (20) in the call to crc32_le.
Michal Hocko [Fri, 24 Jun 2016 21:50:16 +0000 (14:50 -0700)]
oom, suspend: fix oom_reaper vs. oom_killer_disable race
Tetsuo has reported the following potential oom_killer_disable vs.
oom_reaper race:
(1) freeze_processes() starts freezing user space threads.
(2) Somebody (maybe a kenrel thread) calls out_of_memory().
(3) The OOM killer calls mark_oom_victim() on a user space thread
P1 which is already in __refrigerator().
(4) oom_killer_disable() sets oom_killer_disabled = true.
(5) P1 leaves __refrigerator() and enters do_exit().
(6) The OOM reaper calls exit_oom_victim(P1) before P1 can call
exit_oom_victim(P1).
(7) oom_killer_disable() returns while P1 not yet finished
(8) P1 perform IO/interfere with the freezer.
This situation is unfortunate. We cannot move oom_killer_disable after
all the freezable kernel threads are frozen because the oom victim might
depend on some of those kthreads to make a forward progress to exit so
we could deadlock. It is also far from trivial to teach the oom_reaper
to not call exit_oom_victim() because then we would lose a guarantee of
the OOM killer and oom_killer_disable forward progress because
exit_mm->mmput might block and never call exit_oom_victim.
It seems the easiest way forward is to workaround this race by calling
try_to_freeze_tasks again after oom_killer_disable. This will make sure
that all the tasks are frozen or it bails out.
Fixes: 449d777d7ad6 ("mm, oom_reaper: clear TIF_MEMDIE for all tasks queued for oom_reaper") Link: http://lkml.kernel.org/r/1466597634-16199-1-git-send-email-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Gang He [Fri, 24 Jun 2016 21:50:13 +0000 (14:50 -0700)]
ocfs2: disable BUG assertions in reading blocks
According to some high-load testing, these two BUG assertions were
encountered, this led system panic. Actually, there were some
discussions about removing these two BUG() assertions, it would not
bring any side effect.
Then, I did the the following changes,
1) use the existing macro CATCH_BH_JBD_RACES to wrap BUG() in the
ocfs2_read_blocks_sync function like before.
2) disable the macro CATCH_BH_JBD_RACES in Makefile by default.
Link: http://lkml.kernel.org/r/1466574294-26863-1-git-send-email-ghe@suse.com Signed-off-by: Gang He <ghe@suse.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Joseph Qi <joseph.qi@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Rientjes [Fri, 24 Jun 2016 21:50:10 +0000 (14:50 -0700)]
mm, compaction: abort free scanner if split fails
If the memory compaction free scanner cannot successfully split a free
page (only possible due to per-zone low watermark), terminate the free
scanner rather than continuing to scan memory needlessly. If the
watermark is insufficient for a free page of order <= cc->order, then
terminate the scanner since all future splits will also likely fail.
This prevents the compaction freeing scanner from scanning all memory on
very large zones (very noticeable for zones > 128GB, for instance) when
all splits will likely fail while holding zone->lock.
compaction_alloc() iterating a 128GB zone has been benchmarked to take
over 400ms on some systems whereas any free page isolated and ready to
be split ends up failing in split_free_page() because of the low
watermark check and thus the iteration continues.
The next time compaction occurs, the freeing scanner will likely start
at the end of the zone again since no success was made previously and we
get the same lengthy iteration until the zone is brought above the low
watermark. All thp page faults can take >400ms in such a state without
this fix.
Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1606211820350.97086@chino.kir.corp.google.com Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Hugh Dickins <hughd@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dmitry Vyukov [Fri, 24 Jun 2016 21:50:07 +0000 (14:50 -0700)]
mm: prevent KASAN false positives in kmemleak
When kmemleak dumps contents of leaked objects it reads whole objects
regardless of user-requested size. This upsets KASAN. Disable KASAN
checks around object dump.
Gerald Schaefer [Fri, 24 Jun 2016 21:50:04 +0000 (14:50 -0700)]
mm/hugetlb: clear compound_mapcount when freeing gigantic pages
While working on s390 support for gigantic hugepages I ran into the
following "Bad page state" warning when freeing gigantic pages:
BUG: Bad page state in process bash pfn:580001
page:000003d116000040 count:0 mapcount:0 mapping:ffffffff00000000 index:0x0
flags: 0x7fffc0000000000()
page dumped because: non-NULL mapping
This is because page->compound_mapcount, which is part of a union with
page->mapping, is initialized with -1 in prep_compound_gigantic_page(),
and not cleared again during destroy_compound_gigantic_page(). Fix this
by clearing the compound_mapcount in destroy_compound_gigantic_page()
before clearing compound_head.
Interestingly enough, the warning will not show up on x86_64, although
this should not be architecture specific. Apparently there is an
endianness issue, combined with the fact that the union contains both a
64 bit ->mapping pointer and a 32 bit atomic_t ->compound_mapcount as
members. The resulting bogus page->mapping on x86_64 therefore contains 00000000ffffffff instead of ffffffff00000000 on s390, which will falsely
trigger the PageAnon() check in free_pages_prepare() because
page->mapping & PAGE_MAPPING_ANON is true on little-endian architectures
like x86_64 in this case (the page is not compound anymore,
->compound_head was already cleared before). As a result, page->mapping
will be cleared before doing the checks in free_pages_check().
Not sure if the bogus "PageAnon() returning true" on x86_64 for the
first tail page of a gigantic page (at this stage) has other theoretical
implications, but they would also be fixed with this patch.
Link: http://lkml.kernel.org/r/1466612719-5642-1-git-send-email-gerald.schaefer@de.ibm.com Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Luiz Capitulino <lcapitulino@redhat.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Lukasz Odzioba [Fri, 24 Jun 2016 21:50:01 +0000 (14:50 -0700)]
mm/swap.c: flush lru pvecs on compound page arrival
Currently we can have compound pages held on per cpu pagevecs, which
leads to a lot of memory unavailable for reclaim when needed. In the
systems with hundreads of processors it can be GBs of memory.
On of the way of reproducing the problem is to not call munmap
explicitly on all mapped regions (i.e. after receiving SIGTERM). After
that some pages (with THP enabled also huge pages) may end up on
lru_add_pvec, example below.
void main() {
#pragma omp parallel
{
size_t size = 55 * 1000 * 1000; // smaller than MEM/CPUS
void *p = mmap(NULL, size, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS , -1, 0);
if (p != MAP_FAILED)
memset(p, 0, size);
//munmap(p, size); // uncomment to make the problem go away
}
}
When we run it with THP enabled it will leave significant amount of
memory on lru_add_pvec. This memory will be not reclaimed if we hit
OOM, so when we run above program in a loop:
for i in `seq 100`; do ./a.out; done
many processes (95% in my case) will be killed by OOM.
The primary point of the LRU add cache is to save the zone lru_lock
contention with a hope that more pages will belong to the same zone and
so their addition can be batched. The huge page is already a form of
batched addition (it will add 512 worth of memory in one go) so skipping
the batching seems like a safer option when compared to a potential
excess in the caching which can be quite large and much harder to fix
because lru_add_drain_all is way to expensive and it is not really clear
what would be a good moment to call it.
Similarly we can reproduce the problem on lru_deactivate_pvec by adding:
madvise(p, size, MADV_FREE); after memset.
This patch flushes lru pvecs on compound page arrival making the problem
less severe - after applying it kill rate of above example drops to 0%,
due to reducing maximum amount of memory held on pvec from 28MB (with
THP) to 56kB per CPU.
Suggested-by: Michal Hocko <mhocko@suse.com> Link: http://lkml.kernel.org/r/1466180198-18854-1-git-send-email-lukasz.odzioba@intel.com Signed-off-by: Lukasz Odzioba <lukasz.odzioba@intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Ming Li <mingli199x@qq.com> Cc: Minchan Kim <minchan@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tejun Heo [Fri, 24 Jun 2016 21:49:58 +0000 (14:49 -0700)]
memcg: css_alloc should return an ERR_PTR value on error
mem_cgroup_css_alloc() was returning NULL on failure while cgroup core
expected it to return an ERR_PTR value leading to the following NULL
deref after a css allocation failure. Fix it by return
ERR_PTR(-ENOMEM) instead. I'll also update cgroup core so that it
can handle NULL returns.
Tejun Heo [Fri, 24 Jun 2016 21:49:54 +0000 (14:49 -0700)]
memcg: mem_cgroup_migrate() may be called with irq disabled
mem_cgroup_migrate() uses local_irq_disable/enable() but can be called
with irq disabled from migrate_page_copy(). This ends up enabling irq
while holding a irq context lock triggering the following lockdep
warning. Fix it by using irq_save/restore instead.
=================================
[ INFO: inconsistent lock state ]
4.7.0-rc1+ #52 Tainted: G W
---------------------------------
inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage.
kcompactd0/151 [HC0[0]:SC0[0]:HE1:SE1] takes:
(&(&ctx->completion_lock)->rlock){+.?.-.}, at: [<000000000038fd96>] aio_migratepage+0x156/0x1e8
{IN-SOFTIRQ-W} state was registered at:
__lock_acquire+0x5b6/0x1930
lock_acquire+0xee/0x270
_raw_spin_lock_irqsave+0x66/0xb0
aio_complete+0x98/0x328
dio_complete+0xe4/0x1e0
blk_update_request+0xd4/0x450
scsi_end_request+0x48/0x1c8
scsi_io_completion+0x272/0x698
blk_done_softirq+0xca/0xe8
__do_softirq+0xc8/0x518
irq_exit+0xee/0x110
do_IRQ+0x6a/0x88
io_int_handler+0x11a/0x25c
__mutex_unlock_slowpath+0x144/0x1d8
__mutex_unlock_slowpath+0x140/0x1d8
kernfs_iop_permission+0x64/0x80
__inode_permission+0x9e/0xf0
link_path_walk+0x6e/0x510
path_lookupat+0xc4/0x1a8
filename_lookup+0x9c/0x160
user_path_at_empty+0x5c/0x70
SyS_readlinkat+0x68/0x140
system_call+0xd6/0x270
irq event stamp: 971410
hardirqs last enabled at (971409): migrate_page_move_mapping+0x3ea/0x588
hardirqs last disabled at (971410): _raw_spin_lock_irqsave+0x3c/0xb0
softirqs last enabled at (970526): __do_softirq+0x460/0x518
softirqs last disabled at (970519): irq_exit+0xee/0x110
other info that might help us debug this:
Possible unsafe locking scenario:
After revert of 5c0a85fad949 ("mm: make faultaround produce old ptes")
faultaround doesn't have dependencies on hardware accessed bit, so let's
revert this one too.
Link: http://lkml.kernel.org/r/1465893750-44080-3-git-send-email-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reported-by: "Huang, Ying" <ying.huang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Vinayak Menon <vinmenon@codeaurora.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Antoine Tenart [Fri, 24 Jun 2016 21:49:42 +0000 (14:49 -0700)]
mailmap: add Boris Brezillon's email
There are different versions of Boris' name and email in the log, and
one typo. Add his emails in mailmap to have all of his contributions
under the same name/email tuple.
Link: http://lkml.kernel.org/r/20160609130323.27706-2-antoine.tenart@free-electrons.com Signed-off-by: Antoine Tenart <antoine.tenart@free-electrons.com> Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Fri, 24 Jun 2016 21:49:37 +0000 (14:49 -0700)]
mm, sl[au]b: add __GFP_ATOMIC to the GFP reclaim mask
Commit d0164adc89f6 ("mm, page_alloc: distinguish between being unable
to sleep, unwilling to sleep and avoiding waking kswapd") modified
__GFP_WAIT to explicitly identify the difference between atomic callers
and those that were unwilling to sleep. Later the definition was
removed entirely.
The GFP_RECLAIM_MASK is the set of flags that affect watermark checking
and reclaim behaviour but __GFP_ATOMIC was never added. Without it,
atomic users of the slab allocator strip the __GFP_ATOMIC flag and
cannot access the page allocator atomic reserves. This patch addresses
the problem.
The user-visible impact depends on the workload but potentially atomic
allocations unnecessarily fail without this path.
Link: http://lkml.kernel.org/r/20160610093832.GK2527@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Reported-by: Marcin Wojtas <mw@semihalf.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: <stable@vger.kernel.org> [4.4+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrey Ryabinin [Fri, 24 Jun 2016 21:49:34 +0000 (14:49 -0700)]
mm: mempool: kasan: don't poot mempool objects in quarantine
Currently we may put reserved by mempool elements into quarantine via
kasan_kfree(). This is totally wrong since quarantine may really free
these objects. So when mempool will try to use such element,
use-after-free will happen. Or mempool may decide that it no longer
need that element and double-free it.
So don't put object into quarantine in kasan_kfree(), just poison it.
Rename kasan_kfree() to kasan_poison_kfree() to respect that.
Also, we shouldn't use kasan_slab_alloc()/kasan_krealloc() in
kasan_unpoison_element() because those functions may update allocation
stacktrace. This would be wrong for the most of the remove_element call
sites.
(The only call site where we may want to update alloc stacktrace is
in mempool_alloc(). Kmemleak solves this by calling
kmemleak_update_trace(), so we could make something like that too.
But this is out of scope of this patch).
Michal Hocko [Fri, 24 Jun 2016 21:49:28 +0000 (14:49 -0700)]
jbd2: get rid of superfluous __GFP_REPEAT
jbd2_alloc is explicit about its allocation preferences wrt. the
allocation size. Sub page allocations go to the slab allocator and
larger are using either the page allocator or vmalloc. This is all good
but the logic is unnecessarily complex.
1) as per Ted, the vmalloc fallback is a left-over:
: jbd2_alloc is only passed in the bh->b_size, which can't be PAGE_SIZE, so
: the code path that calls vmalloc() should never get called. When we
: conveted jbd2_alloc() to suppor sub-page size allocations in commit
: d2eecb039368, there was an assumption that it could be called with a size
: greater than PAGE_SIZE, but that's certaily not true today.
Moreover vmalloc allocation might even lead to a deadlock because the
callers expect GFP_NOFS context while vmalloc is GFP_KERNEL.
2) __GFP_REPEAT for requests <= PAGE_ALLOC_COSTLY_ORDER is ignored
since the flag was introduced.
Let's simplify the code flow and use the slab allocator for sub-page
requests and the page allocator for others. Even though order > 0 is
not currently used as per above leave that option open.
Link: http://lkml.kernel.org/r/1464599699-30131-18-git-send-email-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Jan Kara <jack@suse.cz> Cc: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Fri, 24 Jun 2016 21:49:25 +0000 (14:49 -0700)]
unicore32: get rid of superfluous __GFP_REPEAT
__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.
PGALLOC_GFP uses __GFP_REPEAT but it is only used in pte_alloc_one,
pte_alloc_one_kernel which does order-0 request. This means that this
flag has never been actually useful here because it has always been used
only for PAGE_ALLOC_COSTLY requests.
Michal Hocko [Fri, 24 Jun 2016 21:49:22 +0000 (14:49 -0700)]
tile: get rid of superfluous __GFP_REPEAT
__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.
pgtable_alloc_one uses __GFP_REPEAT flag for L2_USER_PGTABLE_ORDER but
the order is either 0 or 3 if L2_KERNEL_PGTABLE_SHIFT for HPAGE_SHIFT.
This means that this flag has never been actually useful here because it
has always been used only for PAGE_ALLOC_COSTLY requests.
Michal Hocko [Fri, 24 Jun 2016 21:49:20 +0000 (14:49 -0700)]
sh: get rid of superfluous __GFP_REPEAT
__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.
PGALLOC_GFP uses __GFP_REPEAT but {pgd,pmd}_alloc allocate from
{pgd,pmd}_cache but both caches are allocating up to PAGE_SIZE objects.
This means that this flag has never been actually useful here because it
has always been used only for PAGE_ALLOC_COSTLY requests.
Link: http://lkml.kernel.org/r/1464599699-30131-15-git-send-email-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Rich Felker <dalias@libc.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Fri, 24 Jun 2016 21:49:17 +0000 (14:49 -0700)]
s390: get rid of superfluous __GFP_REPEAT
__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.
page_table_alloc then uses the flag for a single page allocation. This
means that this flag has never been actually useful here because it has
always been used only for PAGE_ALLOC_COSTLY requests.
Link: http://lkml.kernel.org/r/1464599699-30131-14-git-send-email-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Fri, 24 Jun 2016 21:49:14 +0000 (14:49 -0700)]
sparc: get rid of superfluous __GFP_REPEAT
__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.
{pud,pmd}_alloc_one is using __GFP_REPEAT but it always allocates from
pgtable_cache which is initialzed to PAGE_SIZE objects. This means that
this flag has never been actually useful here because it has always been
used only for PAGE_ALLOC_COSTLY requests.
Michal Hocko [Fri, 24 Jun 2016 21:49:12 +0000 (14:49 -0700)]
powerpc: get rid of superfluous __GFP_REPEAT
__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.
{pud,pmd}_alloc_one are allocating from {PGT,PUD}_CACHE initialized in
pgtable_cache_init which doesn't have larger than sizeof(void *) << 12
size and that fits into !costly allocation request size.
PGALLOC_GFP is used only in radix__pgd_alloc which uses either order-0
or order-4 requests. The first one doesn't need the flag while the
second does. Drop __GFP_REPEAT from PGALLOC_GFP and add it for the
order-4 one.
This means that this flag has never been actually useful here because it
has always been used only for PAGE_ALLOC_COSTLY requests.
Michal Hocko [Fri, 24 Jun 2016 21:49:09 +0000 (14:49 -0700)]
score: get rid of superfluous __GFP_REPEAT
__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.
pte_alloc_one{_kernel} allocate PTE_ORDER which is 0. This means that
this flag has never been actually useful here because it has always been
used only for PAGE_ALLOC_COSTLY requests.
Michal Hocko [Fri, 24 Jun 2016 21:49:06 +0000 (14:49 -0700)]
parisc: get rid of superfluous __GFP_REPEAT
__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.
pmd_alloc_one allocate PMD_ORDER which is 1. This means that this flag
has never been actually useful here because it has always been used only
for PAGE_ALLOC_COSTLY requests.
projects / linux-beck.git / log