At the cost of an extra pointer, we can avoid the O(logN) cost of
finding the first element in the tree (smallest node).
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20181206191819.30182-6-dave@stgolabs.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When testing 'perf top' on a armhf system (32-bit, Orange Pi Zero), I
noticed that 'arch_cpu_idle' dominated, add it to the list of idle
symbols, so that we can see what is that being done when not idle.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-4q2b5g4p2hrstrhp9t2mrlho@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Those are simple enough, and usually not produced by root, instead by
whatever user is running java, rust, Node.js JIT code that end up
generating those /tmp/perf-PID.map for resolution of symbols in the
anonymous executable maps.
Having to use --force to resolve symbols in 'perf top' is a distraction,
as recently I experienced when node.js symbols were not being resolved
by 'perf top'.
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Hítalo Silva <hitalos@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/n/tip-tk2jgo2v4v2yjuj28axbpppo@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Perf can take minutes to parse an image when -ffunction-section is used.
This is especially true with the kernel image when it is compiled this
way, which is the arm64 default since the patcheset "Enable deadcode
elimination at link time".
Perf organize maps using a rbtree. Whenever perf finds a new symbols, it
first searches this rbtree for the map it belongs to, by strcmp()'aring
section names. When it finds the map with the right name, it uses it to
add the symbol. With a usual image there aren't so many maps but when
using -ffunction-section there's basically one map per function. With
the kernel image that's north of 40,000 maps. For most symbols perf has
to parses the entire rbtree to eventually create a new map and add it.
Consequently perf spends most of the time browsing a rbtree that keeps
getting larger.
This performance fix introduces a secondary rbtree that indexes maps
based on the section name.
Signed-off-by: Eric Saint-Etienne <eric.saint.etienne@oracle.com>
Reviewed-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Reviewed-by: David Aldridge <david.aldridge@oracle.com>
Reviewed-by: Rob Gardner <rob.gardner@oracle.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1542822679-25591-1-git-send-email-eric.saint.etienne@oracle.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We were not considering 'B' and 'b' (BSS, uninitialized data objects,
that gets set to zero at program start), do it so that we can resolve
more symbols in tools doing resolution of data operands, like 'perf c2c'.
When using vmlinux, i.e. an ELF symbol table, those were already
considered, as the decision was about STT_FUNC or STT_OBJECT, and the
later covers BSS symbols.
# grep -i ' b ' /proc/kallsyms | head -20 | tail -5
ffffffffa789d030 b execute_command
ffffffffa789d038 b initcall_command_line
ffffffffa789d040 b static_command_line
ffffffffa789d048 B ROOT_DEV
ffffffffa789d050 b once.73786
#
# readelf -s /lib/modules/`uname -r`/build/vmlinux | grep ROOT_DEV
79219: ffffffff8289d048 4 OBJECT GLOBAL DEFAULT 58 ROOT_DEV
#
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: https://lkml.kernel.org/n/tip-z960xobig39ca1pmp5brl2fr@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Continuing to group annotation options in an annotation specific struct.
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: https://lkml.kernel.org/n/tip-astei92tzxp4yccag5pxb2h7@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Create maps for x86 PTI entry trampolines, based on symbols found in
kallsyms. It is also necessary to keep track of whether the trampolines
have been mapped particularly when the kernel dso is kcore.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1526986485-6562-9-git-send-email-adrian.hunter@intel.com
[ Fix extra_kernel_map_info.cnt designed struct initializer on gcc 4.4.7 (centos:6, etc) ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Identify extra kernel maps by name so that they can be distinguished
from the kernel map and module maps.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1526986485-6562-8-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When kernel symbols are derived from /proc/kallsyms only (not using
vmlinux or /proc/kcore) map_groups__split_kallsyms() is used. However
that function makes assumptions that are not true with entry trampoline
symbols. For now, remove the entry trampoline symbols at that point, as
they are no longer needed at that point.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1526986485-6562-7-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
On x86_64 the PTI entry trampolines are not in the kernel map created by
perf tools. That results in the addresses having no symbols and prevents
annotation. It also causes Intel PT to have decoding errors at the
trampoline addresses.
Workaround that by creating maps for the trampolines.
At present the kernel does not export information revealing where the
trampolines are. Until that happens, the addresses are hardcoded.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1526986485-6562-6-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The first symbol is not necessarily in the kernel text. Instead of
using the first symbol, use the _stest symbol to identify the kernel map
when loading kcore.
This allows for the introduction of symbols to identify the x86_64 PTI
entry trampolines.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1525866228-30321-6-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Since it mainly will populate symtabs of its maps (kernel modules).
While looking at this I wonder if map_groups__split_kallsyms_for_kcore()
shouldn't be all that we need, seems much simpler.
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: https://lkml.kernel.org/n/tip-3d1f3iby76popdr8ia9yimsc@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It was only using the map to obtain its kmap, so do the validation in
its called, __dso__load_kallsyms() and pass the kmap, that will be used
in the following patches in similar simplifications.
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: https://lkml.kernel.org/n/tip-u6p9hbonlqzpl6o1z9xzxd75@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Only the 'dso' is needed, so ditch the struct used to pass (map, dso),
passing just the used 'dso' pointer.
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: https://lkml.kernel.org/n/tip-17a4gkk1cs4up4smkviymi2g@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Remove the split of symbol tables for data (MAP__VARIABLE) and for
functions (MAP__FUNCTION), its unneeded and there were various places
doing two lookups to find a symbol, so simplify this.
We still will consider only the symbols that matched the filters in
place, i.e. see the (elf_(sec,sym)|symbol_type)__filter() routines in
the patch, just so that we consider only the same symbols as before,
to reduce the possibility of regressions.
All the tests on 50-something build environments, in varios versions
of lots of distros and cross build environments were performed without
build regressions, as usual with all pull requests the other tests were
also performed: 'perf test' and 'make -C tools/perf build-test'.
Also this was done at a great granularity so that regressions can be
bisected more easily.
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: https://lkml.kernel.org/n/tip-hiq0fy2rsleupnqqwuojo1ne@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Its equivalent, one less use of enum map_type.
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: https://lkml.kernel.org/n/tip-6m18iv1ty7nh7kxlfmn89sgz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There is code that needs to see if a resolved address is a function, so,
since we're going to ditch the MAP__{FUNCTION,VARIABLE} split, store
that info in the per symbol struct.
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: https://lkml.kernel.org/n/tip-9ugwxz0i8ryg5702rx8u5q6z@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
One more step to ditch MAP__{VARIABLE,FUNCTION}
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: https://lkml.kernel.org/n/tip-919d1k13ts62pjipnpibvgwd@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Only the symbol core needs to use that, so provide a __ variant for that
case, that will end up removed when we ditch the MAP__ split.
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: https://lkml.kernel.org/n/tip-x29k9e1ohastsoqbilp3mguh@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Now this is only used in the symbols.c file, where it will finally
disappear when we remove the MAP_{FUNCTION,VARIABLE} split.
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: https://lkml.kernel.org/n/tip-a9t4d4hfrycczq9vpsk5sr8q@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
All users want MAP__FUNCTION, and this split is going away.
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: https://lkml.kernel.org/n/tip-sm72zwt1f03ma5uw78l6zze0@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Removing the map_type, that is going away.
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: https://lkml.kernel.org/n/tip-18iiiw25r75xn7zlppjldk48@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Another step in the road to elliminate the MAP_{FUNCTION,VARIABLE}
separation, reducing the exposure to these details in the tools using
the symbol APIs.
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: https://lkml.kernel.org/n/tip-8a1hvrqe3r5i0kw865u3uxwt@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Shorter, should be equivalent code, use 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: https://lkml.kernel.org/n/tip-q90olng8sfkvrnsrwu7xnul6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In the TUI the 's' hotkey can be used to switch to another perf.data
file in the current directory, but that got broken in Fixes:
b01141f4f5 ("perf annotate: Initialize the priv are in symbol__new()"),
that would show this once another file was chosen:
┌─Fatal Error─────────────────────────────────────┐
│Annotation needs to be init before symbol__init()│
│ │
│ │
│Press any key... │
└─────────────────────────────────────────────────┘
Fix it by just silently bailing out if symbol__annotation_init() was already
called, just like is done with symbol__init(), i.e. they are done just once at
session start, not when switching to a new perf.data file.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Martin Liška <mliska@suse.cz>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Thomas Richter <tmricht@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: b01141f4f5 ("perf annotate: Initialize the priv are in symbol__new()")
Link: https://lkml.kernel.org/n/tip-ogppdtpzfax7y1h6gjdv5s6u@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It's passed along several hists entries in --hierarchy mode, so it's
better we keep track of it.
The current fail I see is that it gets removed in hierarchy --mem-mode
mode, where it's shared in the different hierarchies, but removed from
the template hist entry, so the report crashes.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180307155020.32613-6-jolsa@kernel.org
[ Rename mem_info__aloc() to mem_info__new(), to fix the typo and use the convention for constructors ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
It simplifies and centralizes the code. The kernel mmap name is set for
machine type, which we know from the beginning, so there's no reason to
generate it every time we need it.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180215122635.24029-5-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The current code in dso__load() calls is_regular_file(), but it checks
its return value only after calling symsrc__init().
That can make symsrc__init() block in elf_* functions on reading
the file if the file happens to be device and not regular one.
Call symsrc__init() only for regular files. Also remove the
symsrc__destroy() cleanup, which is not needed now, because we call
symsrc__init() only for regular files.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180215122635.24029-3-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit d80406453a ("perf symbols: Allow user probes on versioned
symbols") allows user to find default versioned symbols (with "@@") in
map. However, it did not enable normal versioned symbol (with "@") for
perf-probe. E.g.
=====
# ./perf probe -x /lib64/libc-2.25.so malloc_get_state
Failed to find symbol malloc_get_state in /usr/lib64/libc-2.25.so
Error: Failed to add events.
=====
This solves above issue by improving perf-probe symbol search function,
as below.
=====
# ./perf probe -x /lib64/libc-2.25.so malloc_get_state
Added new event:
probe_libc:malloc_get_state (on malloc_get_state in /usr/lib64/libc-2.25.so)
You can now use it in all perf tools, such as:
perf record -e probe_libc:malloc_get_state -aR sleep 1
# ./perf probe -l
probe_libc:malloc_get_state (on malloc_get_state@GLIBC_2.2.5 in /usr/lib64/libc-2.25.so)
=====
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Acked-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: bhargavb <bhargavaramudu@gmail.com>
Cc: linux-rt-users@vger.kernel.org
Link: http://lkml.kernel.org/r/151275049269.24652.1639103455496216255.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that we have caches in place to speed up the process of finding
inlined frames and srcline information repeatedly, we can enable this
useful option by default.
Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20171019113836.5548-6-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Andi reported a performance drop in single threaded perf tools such as
'perf script' due to the growing number of locks being put in place to
allow for multithreaded tools, so wrap the POSIX threads rwlock routines
with the names used for such kinds of locks in the Linux kernel and then
allow for tools to ask for those locks to be used or not.
I.e. a tool may have a multithreaded phase and then switch to single
threaded, like the upcoming patches for the synthesizing of
PERF_RECORD_{FORK,MMAP,etc} for pre-existing processes to then switch to
single threaded mode in 'perf top'.
The init routines will not be conditional, this way starting as single
threaded to then move to multi threaded mode should be possible.
Reported-by: Andi Kleen <ak@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20170404161739.GH12903@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
During work on perf report for s390 I ran into the following issue:
0 0x318 [0x78]: PERF_RECORD_MMAP -1/0:
[0x3ff804d6990(0xfffffc007fb2966f) @ 0]:
x /lib/modules/4.12.0perf1+/kernel/drivers/s390/net/qeth_l2.ko
This is a PERF_RECORD_MMAP entry of the perf.data file with an invalid
module size for qeth_l2.ko (the s390 ethernet device driver).
Even a mainframe does not have 0xfffffc007fb2966f bytes of main memory.
It turned out that this wrong size is created by the perf record
command. What happens is this function call sequence from
__cmd_record():
perf_session__new():
perf_session__create_kernel_maps():
machine__create_kernel_maps():
machine__create_modules(): Creates map for all loaded kernel modules.
modules__parse(): Reads /proc/modules and extracts module name and
load address (1st and last column)
machine__create_module(): Called for every module found in /proc/modules.
Creates a new map for every module found and enters
module name and start address into the map. Since the
module end address is unknown it is set to zero.
This ends up with a kernel module map list sorted by module start
addresses. All module end addresses are zero.
Last machine__create_kernel_maps() calls function map_groups__fixup_end().
This function iterates through the maps and assigns each map entry's
end address the successor map entry start address. The last entry of the
map group has no successor, so ~0 is used as end to consume the remaining
memory.
Later __cmd_record calls function record__synthesize() which in turn calls
perf_event__synthesize_kernel_mmap() and perf_event__synthesize_modules()
to create PERF_REPORT_MMAP entries into the perf.data file.
On s390 this results in the last module qeth_l2.ko
(which has highest start address, see module table:
[root@s8360047 perf]# cat /proc/modules
qeth_l2 86016 1 - Live 0x000003ff804d6000
qeth 266240 1 qeth_l2, Live 0x000003ff80296000
ccwgroup 24576 1 qeth, Live 0x000003ff80218000
vmur 36864 0 - Live 0x000003ff80182000
qdio 143360 2 qeth_l2,qeth, Live 0x000003ff80002000
[root@s8360047 perf]# )
to be the last entry and its map has an end address of ~0.
When the PERF_RECORD_MMAP entry is created for kernel module qeth_l2.ko
its start address and length is written. The length is calculated in line:
event->mmap.len = pos->end - pos->start;
and results in 0xffffffffffffffff - 0x3ff804d6990(*) = 0xfffffc007fb2966f
(*) On s390 the module start address is actually determined by a __weak function
named arch__fix_module_text_start() in machine__create_module().
I think this improvable. We can use the module size (2nd column of /proc/modules)
to get each loaded kernel module size and calculate its end address.
Only for map entries which do not have a valid end address (end is still zero)
we can use the heuristic we have now, that is use successor start address or ~0.
Signed-off-by: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Cc: Zvonko Kosic <zvonko.kosic@de.ibm.com>
LPU-Reference: 20170803134902.47207-2-tmricht@linux.vnet.ibm.com
Link: http://lkml.kernel.org/n/tip-nmoqij5b5vxx7rq2ckwu8iaj@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If a stripped binary is placed in the cache, the user is in a situation
where there's a cached elf file present, but it doesn't have any symtab
to use for name resolution. Grab the debuginfo for binaries that don't
end in .ko. This yields a better chance of resolving symbols from older
traces.
Signed-off-by: Krister Johansen <kjlx@templeofstupid.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1499305693-1599-7-git-send-email-kjlx@templeofstupid.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Teach buildid-cache how to add, remove, and update binary objects from
other mount namespaces. Allow probe events tracing binaries in
different namespaces to add their objects to the probe and build-id
caches too. As a handy side effect, this also lets us access SDT probes
in binaries from alternate mount namespaces.
Signed-off-by: Krister Johansen <kjlx@templeofstupid.com>
Tested-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1499305693-1599-5-git-send-email-kjlx@templeofstupid.com
[ Add util/namespaces.c to tools/perf/util/python-ext-sources, to fix the python binding 'perf test' ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If a process is in a mountns and has symbols in /tmp/perf-<pid>.map,
look first in the namespace using the tgid for the pidns that the
process might be in. If the map isn't found there, try looking in the
mountns where perf is running, and use the tgid that's appropriate for
perf's pid namespace. If all else fails, use the original pid.
This allows us to locate a symbol map file in the mount namespace, if it
was generated there. However, we also try the tool's /tmp in case it's
there instead.
Signed-off-by: Krister Johansen <kjlx@templeofstupid.com>
Tested-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1499305693-1599-3-git-send-email-kjlx@templeofstupid.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Teach perf how to resolve symbols from binaries that are in a different
mount namespace from the tool. This allows perf to generate meaningful
stack traces even if the binary resides in a different mount namespace
from the tool.
Signed-off-by: Krister Johansen <kjlx@templeofstupid.com>
Tested-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1499305693-1599-2-git-send-email-kjlx@templeofstupid.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The commit e7ee404757 ("perf symbols: Fix symbols searching for module
in buildid-cache") added the function to check kernel modules reside in
the build-id cache. This was because there's no way to identify a DSO
which is actually a kernel module. So it searched linkname of the file
and find ".ko" suffix.
But this does not work for compressed kernel modules and now such DSOs
hCcave correct symtab_type now. So no need to check it anymore. This
patch essentially reverts the commit.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170608073109.30699-10-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Symbol versioning, as in glibc, results in symbols being defined as:
<real symbol>@[@]<version>
(Note that "@@" identifies a default symbol, if the symbol name is
repeated.)
perf is currently unable to deal with this, and is unable to create user
probes at such symbols:
--
$ nm /lib/powerpc64le-linux-gnu/libpthread.so.0 | grep pthread_create
0000000000008d30 t __pthread_create_2_1
0000000000008d30 T pthread_create@@GLIBC_2.17
$ /usr/bin/sudo perf probe -v -x /lib/powerpc64le-linux-gnu/libpthread.so.0 pthread_create
probe-definition(0): pthread_create
symbol:pthread_create file:(null) line:0 offset:0 return:0 lazy:(null)
0 arguments
Open Debuginfo file: /usr/lib/debug/lib/powerpc64le-linux-gnu/libpthread-2.19.so
Try to find probe point from debuginfo.
Probe point 'pthread_create' not found.
Error: Failed to add events. Reason: No such file or directory (Code: -2)
--
One is not able to specify the fully versioned symbol, either, due to
syntactic conflicts with other uses of "@" by perf:
--
$ /usr/bin/sudo perf probe -v -x /lib/powerpc64le-linux-gnu/libpthread.so.0 pthread_create@@GLIBC_2.17
probe-definition(0): pthread_create@@GLIBC_2.17
Semantic error :SRC@SRC is not allowed.
0 arguments
Error: Command Parse Error. Reason: Invalid argument (Code: -22)
--
This patch ignores versioning for default symbols, thus allowing probes to be
created for these symbols:
--
$ /usr/bin/sudo ./perf probe -x /lib/powerpc64le-linux-gnu/libpthread.so.0 pthread_create
Added new event:
probe_libpthread:pthread_create (on pthread_create in /lib/powerpc64le-linux-gnu/libpthread-2.19.so)
You can now use it in all perf tools, such as:
perf record -e probe_libpthread:pthread_create -aR sleep 1
$ /usr/bin/sudo ./perf record -e probe_libpthread:pthread_create -aR ./test 2
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.052 MB perf.data (2 samples) ]
$ /usr/bin/sudo ./perf script
test 2915 [000] 19124.260729: probe_libpthread:pthread_create: (3fff99248d38)
test 2916 [000] 19124.260962: probe_libpthread:pthread_create: (3fff99248d38)
$ /usr/bin/sudo ./perf probe --del=probe_libpthread:pthread_create
Removed event: probe_libpthread:pthread_create
--
Committer note:
Change the variable storing the result of strlen() to 'int', to fix the build
on debian:experimental-x-mipsel, fedora:24-x-ARC-uClibc, ubuntu:16.04-x-arm,
etc:
util/symbol.c: In function 'symbol__match_symbol_name':
util/symbol.c:422:11: error: comparison between signed and unsigned integer expressions [-Werror=sign-compare]
if (len < versioning - name)
^
Signed-off-by: Paul A. Clarke <pc@us.ibm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Link: http://lkml.kernel.org/r/c2b18d9c-17f8-9285-4868-f58b6359ccac@us.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
That is the case of _text on s390, and we have some functions that return an
address, using address zero to report problems, oops.
This would lead the symbol loading routines to not use "_text" as the reference
relocation symbol, or the first symbol for the kernel, but use instead
"_stext", that is at the same address on x86_64 and others, but not on s390:
[acme@localhost perf-4.11.0-rc6]$ head -15 /proc/kallsyms
0000000000000000 T _text
0000000000000418 t iplstart
0000000000000800 T start
000000000000080a t .base
000000000000082e t .sk8x8
0000000000000834 t .gotr
0000000000000842 t .cmd
0000000000000846 t .parm
000000000000084a t .lowcase
0000000000010000 T startup
0000000000010010 T startup_kdump
0000000000010214 t startup_kdump_relocated
0000000000011000 T startup_continue
00000000000112a0 T _ehead
0000000000100000 T _stext
[acme@localhost perf-4.11.0-rc6]$
Which in turn would make 'perf test vmlinux' to fail because it wouldn't find
the symbols before "_stext" in kallsyms.
Fix it by using the return value only for errors and storing the
address, when the symbol is successfully found, in a provided pointer
arg.
Before this patch:
After:
[acme@localhost perf-4.11.0-rc6]$ tools/perf/perf test -v 1
1: vmlinux symtab matches kallsyms :
--- start ---
test child forked, pid 40693
Looking at the vmlinux_path (8 entries long)
Using /usr/lib/debug/lib/modules/3.10.0-654.el7.s390x/vmlinux for symbols
ERR : 0: _text not on kallsyms
ERR : 0x418: iplstart not on kallsyms
ERR : 0x800: start not on kallsyms
ERR : 0x80a: .base not on kallsyms
ERR : 0x82e: .sk8x8 not on kallsyms
ERR : 0x834: .gotr not on kallsyms
ERR : 0x842: .cmd not on kallsyms
ERR : 0x846: .parm not on kallsyms
ERR : 0x84a: .lowcase not on kallsyms
ERR : 0x10000: startup not on kallsyms
ERR : 0x10010: startup_kdump not on kallsyms
ERR : 0x10214: startup_kdump_relocated not on kallsyms
ERR : 0x11000: startup_continue not on kallsyms
ERR : 0x112a0: _ehead not on kallsyms
<SNIP warnings>
test child finished with -1
---- end ----
vmlinux symtab matches kallsyms: FAILED!
[acme@localhost perf-4.11.0-rc6]$
After:
[acme@localhost perf-4.11.0-rc6]$ tools/perf/perf test -v 1
1: vmlinux symtab matches kallsyms :
--- start ---
test child forked, pid 47160
<SNIP warnings>
test child finished with 0
---- end ----
vmlinux symtab matches kallsyms: Ok
[acme@localhost perf-4.11.0-rc6]$
Reported-by: Michael Petlan <mpetlan@redhat.com>
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-9x9bwgd3btwdk1u51xie93fz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Disentangling util.h header mess a bit more.
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-aj6je8ly377i4upedmjzdsq6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
More stuff that came from git, out of the hodge-podge that is util.h
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-e3lana4gctz3ub4hn4y29hkw@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To pave the way for further cleanups where linux/kernel.h may stop being
included in some header.
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-qqxan6tfsl6qx3l0v3nwgjvk@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The current symbols__fixup_end() heuristic for the last entry in the rb
tree is suboptimal as it leads to not being able to recognize the symbol
in the call graph in a couple of corner cases, for example:
i) If the symbol has a start address (f.e. exposed via kallsyms)
that is at a page boundary, then the roundup(curr->start, 4096)
for the last entry will result in curr->start == curr->end with
a symbol length of zero.
ii) If the symbol has a start address that is shortly before a page
boundary, then also here, curr->end - curr->start will just be
very few bytes, where it's unrealistic that we could perform a
match against.
Instead, change the heuristic to roundup(curr->start, 4096) + 4096, so
that we can catch such corner cases and have a better chance to find
that specific symbol. It's still just best effort as the real end of the
symbol is unknown to us (and could even be at a larger offset than the
current range), but better than the current situation.
Alexei reported that he recently run into case i) with a JITed eBPF
program (these are all page aligned) as the last symbol which wasn't
properly shown in the call graph (while other eBPF program symbols in
the rb tree were displayed correctly). Since this is a generic issue,
lets try to improve the heuristic a bit.
Reported-and-Tested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Fixes: 2e538c4a18 ("perf tools: Improve kernel/modules symbol lookup")
Link: http://lkml.kernel.org/r/bb5c80d27743be6f12afc68405f1956a330e1bc9.1489614365.git.daniel@iogearbox.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
After commit 5baecbcd9c ("perf symbols: we can now read separate
debug-info files based on a build ID") and when --symfs option is used
perf failed to pick up symbols for file with the same name between host
and sysroot specified by --symfs option. One can see message like this:
bin/bash with build id 26f0062cb6950d4d1ab0fd9c43eae8b10ca42062 not found, continuing without symbols
It happens because code added by 5baecbcd9c opens files directly by
dso->long_name without symbol_conf.symfs consideration, which as result
picks one from the host. It reads its build ID and later even code finds
another proper file in directory pointed by --symfs perf ignores it
because build id mismatches.
Fix is to use __symbol__join_symfs to adjust file name according to
--symfs setting. If no --symfs passed the operation would noop and picks
the same host file as before.
Also note in latter tree after 5baecbcd9c commit additional check for
'!dso->has_build_id' was added, so to observe error condition 'perf
record' should run with --no-buildid, so perf.data itself would not have
build id for target binary in buildid perf section and 'perf report'
will pass '!dso->has_build_id' condition. Or target binary should not
have build id, but the same binary on host has build id, again
'!dso->has_build_id' will pass in this case and incorrect build id could
be read if --symfs is used.
Signed-off-by: Victor Kamensky <kamensky@cisco.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Chris Phlipot <cphlipot0@gmail.com>
Cc: Dima Kogan <dima@secretsauce.net>
Cc: He Kuang <hekuang@huawei.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: xe-linux-external@cisco.com
Fixes: 5baecbcd9c ("perf symbols: we can now read separate debug-info files based on a build ID")
Link: http://lkml.kernel.org/r/1486424908-17094-1-git-send-email-kamensky@cisco.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fixes a perf diff regression issue which was introduced by commit
5baecbcd9c ("perf symbols: we can now read separate debug-info files
based on a build ID")
The binary name could be same when perf diff different binaries. Build
id is used to distinguish between them.
However, the previous patch assumes the same binary name has same build
id. So it overwrites the build id according to the binary name,
regardless of whether the build id is set or not.
Check the has_build_id in dso__load. If the build id is already set, use
it.
Before the fix:
$ perf diff 1.perf.data 2.perf.data
# Event 'cycles'
#
# Baseline Delta Shared Object Symbol
# ........ ....... ................ .............................
#
99.83% -99.80% tchain_edit [.] f2
0.12% +99.81% tchain_edit [.] f3
0.02% -0.01% [ixgbe] [k] ixgbe_read_reg
After the fix:
$ perf diff 1.perf.data 2.perf.data
# Event 'cycles'
#
# Baseline Delta Shared Object Symbol
# ........ ....... ................ .............................
#
99.83% +0.10% tchain_edit [.] f3
0.12% -0.08% tchain_edit [.] f2
Signed-off-by: Kan Liang <kan.liang@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
CC: Dima Kogan <dima@secretsauce.net>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Fixes: 5baecbcd9c ("perf symbols: we can now read separate debug-info files based on a build ID")
Link: http://lkml.kernel.org/r/1481642984-13593-1-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Before this patch perf panics if kptr_restrict is set to 1 and perf is
owned by root with suid set:
$ whoami
wangnan
$ ls -l ./perf
-rwsr-xr-x 1 root root 19781908 Sep 21 19:29 /home/wangnan/perf
$ cat /proc/sys/kernel/kptr_restrict
1
$ cat /proc/sys/kernel/perf_event_paranoid
-1
$ ./perf record -a
Segmentation fault (core dumped)
$
The reason is that perf assumes it is allowed to read kptr from
/proc/kallsyms when euid is root, but in fact the kernel doesn't allow
reading kptr when euid and uid do not match with each other:
$ cp /bin/cat .
$ sudo chown root:root ./cat
$ sudo chmod u+s ./cat
$ cat /proc/kallsyms | grep do_fork
0000000000000000 T _do_fork <--- kptr is hidden even euid is root
$ sudo cat /proc/kallsyms | grep do_fork
ffffffff81080230 T _do_fork
See lib/vsprintf.c for kernel side code.
This patch fixes this problem by checking both uid and euid.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/20161115040617.69788-3-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add a function to find the last symbol in a DSO. This will be used when
parsing address filters to calculate a region that includes the entire
DSO.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: http://lkml.kernel.org/r/1474641528-18776-7-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
