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* tools lib traceevent: Support %ps/%pSScott Wood2015-10-221-2/+2
| | | | | | | | | | | | | | | | Commits such as 65dd297ac25565 ("xfs: %pF is only for function pointers") caused a regression because pretty_print() didn't support %ps/%pS. The current %pf/%pF implementation in pretty_print() is what %ps/%pS is supposed to do, so use the same code for %ps/%pS. Addressing the incorrect %pf/%pF implementation is beyond the scope of this patch. Signed-off-by: Scott Wood <scottwood@freescale.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Dave Chinner <david@fromorbit.com> Link: http://lkml.kernel.org/r/20150831211637.GA12848@home.buserror.net Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* tools lib traceevent: update KVM pluginPaolo Bonzini2015-10-201-8/+17
| | | | | | | | | | | | | The format of the role word has changed through the years and the plugin was never updated; some VMX exit reasons were missing too. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: kvm@vger.kernel.org Link: http://lkml.kernel.org/r/1443695293-31127-1-git-send-email-pbonzini@redhat.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* tools lib api fs: No need to use PATH_MAX + 1Jiri Olsa2015-10-052-4/+4
| | | | | | | | | | | | | Because there's no point, PATH_MAX is big enough. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Don Zickus <dzickus@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1444068369-20978-2-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* tools lib symbol: Introduce kallsyms2elf_typeArnaldo Carvalho de Melo2015-09-302-0/+8
| | | | | | | | | | | | | Map 't', 'T' (text, local, global), 'w' and 'W' (weak text, local, global) as STT_FUNC, and the rest as STT_OBJECT Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-sbwcixulpc5v1xuxn3xvm0nn@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* tools lib symbol: Rename kallsyms2elf_type to kallsyms2elf_bindingArnaldo Carvalho de Melo2015-09-301-1/+1
| | | | | | | | | | | | | | | It is about binding, not type, we have just a letter in kallsyms that should map both for the ELF type (STT_FUNC, etc) and to the ELF symbol binding (STB_WEAK, STB_GLOBAL, etc), so rename it now before introducing kallsyms2_elf_type() Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-uu5vj343ms1q2wm55690on6v@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* tools build: Build fixdep helper from perf and basic libsJiri Olsa2015-09-283-3/+9
| | | | | | | | | | | | | Adding the fixdep target into the Makefile.include to ease up building of fixdep helper, that needs to be built before we dive in to the build itself. The user can invoke the fixdep target to build the helper. 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/1443004442-32660-8-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* tools build: Add Makefile.includeJiri Olsa2015-09-283-3/+3
| | | | | | | | | | | | | To ease up build framework code setup for users. More shared code will be added in the following patches. 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/1443004442-32660-2-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* tools lib api fs: Store tracing mountpoint for better error messageJiri Olsa2015-09-281-10/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Storing the actual tracing path mountpoint to display correct error message hint ('Hint:' line). The error hint rediscovers mountpoints, but it could be different from what we actually used in tracing path. Before we'd display debugfs mount even though tracefs was used: $ perf record -e sched:sched_krava ls event syntax error: 'sched:sched_krava' \___ can't access trace events Error: No permissions to read /sys/kernel/debug/tracing/events/sched/sched_krava Hint: Try 'sudo mount -o remount,mode=755 /sys/kernel/debug' ... After this change, correct mountpoint is displayed: $ perf record -e sched:sched_krava ls event syntax error: 'sched:sched_krava' \___ can't access trace events Error: No permissions to read /sys/kernel/debug/tracing/events/sched/sched_krava Hint: Try 'sudo mount -o remount,mode=755 /sys/kernel/debug/tracing' ... Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Raphael Beamonte <raphael.beamonte@gmail.com> Link: http://lkml.kernel.org/r/1442674027-19427-1-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* Merge tag 'perf-core-for-mingo' of ↵Ingo Molnar2015-09-231-2/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: User visible changes: - Fix a segfault in 'perf probe' when removing uprobe events. (Masami Hiramatsu) - Synthesize COMM event for workloads started from the command line in 'perf record' so that we can have the pid->comm mapping before we get the real PERF_RECORD_COMM switching from perf to the workload. (Namhyung Kim) - Fix build tools/vm/ due to removal of tools/lib/api/fs/debugfs.h. (Arnaldo Carvalho de Melo) Infrastructure changes: - Fix the make tarball targets by including the recently added err.h header in the perf MANIFEST file. (Jiri Olsa) - Don't assume that the event parser returns a non empty evlist. (Wang Nan) - Add way to disambiguate feature detection state files, needed to use tools/build feature detection for multiple components in a single O= output dir, which will be the case with tools/perf/ and tools/lib/bpf/. (Arnaldo Carvalho de Melo) - Fixup FEATURE_{TESTS,DISPLAY} inversion in tools/lib/bpf/. (Arnaldo Carvalho de Melo) Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * tools lib bpf: Use FEATURE_USER to allow building in the same dir as perfArnaldo Carvalho de Melo2015-09-221-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When building tools/lib/bpf as part of the tools/perf/ build process, which will happend when we introduce a patch wiring that up, we end up stomping on the feature detection caching mechanism, that uses a file in the output directory (O=) that is shared by libbpf and perf to check if something changed from one build to another that requires redoing the feature detection process. By using the recently introduced FEATURE_USER tools/build/ knob, we can avoid that: Before, every make invokation would run the feature detection: $ make O=/tmp/build/perf -C tools/perf make: Entering directory '/home/git/linux/tools/perf' Auto-detecting system features: ... dwarf: [ on ] ... glibc: [ on ] <SNIP> ... get_cpuid: [ on ] ... bpf: [ on ] GEN perf-archive GEN perf-with-kcore Auto-detecting system features: ... libelf: [ on ] ... bpf: [ on ] <SNIP> After: $ make O=/tmp/build/perf -C tools/perf make: Entering directory '/home/git/linux/tools/perf' BUILD: Doing 'make -j4' parallel build make: Leaving directory '/home/git/linux/tools/perf' $ Because we now have two different feature detection state files: $ ls -la /tmp/build/perf/FEATURE-DUMP* -rw-rw-r--. 1 acme acme 338 Sep 21 17:25 /tmp/build/perf/FEATURE-DUMP -rw-rw-r--. 1 acme acme 33 Sep 21 17:25 /tmp/build/perf/FEATURE-DUMP.libbpf $ Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Stephane Eranian <eranian@google.com> Cc: Wang Nan <wangnan0@huawei.com> Cc: pi3orama@163.com Fixes: 1b76c13e4b36 ("bpf tools: Introduce 'bpf' library and add bpf feature check") Link: http://lkml.kernel.org/n/tip-s6ev9wfqy7pvvs58emys2g90@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * tools lib bpf: Fix up FEATURE_{TESTS,DISPLAY} usageArnaldo Carvalho de Melo2015-09-221-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When libbpf was introduced it wrongly asked for the "libelf" and "bpf" feature tests to be performed (via FEATURE_TESTS), while asking that "libbpf", "libelf-mmap", "libelf-getphdrnum" and "bpf" to have the result of its respective tests to be displayed (via FEATURE_DISPLAY). Due to another recently bug fixed in the tools/build/ infrastructure ("tools build: Fixup feature detection display function name") the results for the entries in the FEATURE_DISPLAY, for this case, were appearing as all succeeding, when two of them (the ones only on the DISPLAY) were not even being performed. Before: $ make -C tools/lib/bpf/ make: Entering directory '/home/git/linux/tools/lib/bpf' Auto-detecting system features: ... libelf: [ on ] ... libelf-getphdrnum: [ OFF ] ... libelf-mmap: [ OFF ] ... bpf: [ on ] <SNIP> After, with FEATURE_TESTS == FEATURE_DISPLAY: Auto-detecting system features: ... libelf: [ on ] ... libelf-getphdrnum: [ on ] ... libelf-mmap: [ on ] ... bpf: [ on ] <SNIP> I just inverted, so that it tests the four features but displays just the libelf and mmap ones, to make it more compact. So it becomes: $ make -C tools/lib/bpf/ make: Entering directory '/home/git/linux/tools/lib/bpf' Auto-detecting system features: ... libelf: [ on ] ... bpf: [ on ] Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Stephane Eranian <eranian@google.com> Cc: Wang Nan <wangnan0@huawei.com> Cc: pi3orama@163.com Fixes: 1b76c13e4b36 ("bpf tools: Introduce 'bpf' library and add bpf feature check") Link: http://lkml.kernel.org/n/tip-y4bd59e6j9rzzojiyeqrg2jq@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | Merge branch 'perf/urgent' into perf/core to pick up fixes before pulling ↵Ingo Molnar2015-09-231-3/+20
|\ \ | |/ |/| | | | | | | new changes Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * tools lib traceevent: Fix string handling in heterogeneous arch environmentsKapileshwar Singh2015-09-221-3/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a trace recorded on a 32-bit device is processed with a 64-bit binary, the higher 32-bits of the address need to ignored. The lack of this results in the output of the 64-bit pointer value to the trace as the 32-bit address lookup fails in find_printk(). Before: burn-1778 [003] 548.600305: bputs: 0xc0046db2s: 2cec5c058d98c After: burn-1778 [003] 548.600305: bputs: 0xc0046db2s: RT throttling activated The problem occurs in PRINT_FIELD when the field is recognized as a pointer to a string (of the type const char *) Heterogeneous architectures cases below can arise and should be handled: * Traces recorded using 32-bit addresses processed on a 64-bit machine * Traces recorded using 64-bit addresses processed on a 32-bit machine Reported-by: Juri Lelli <juri.lelli@arm.com> Signed-off-by: Kapileshwar Singh <kapileshwar.singh@arm.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: David Ahern <dsahern@gmail.com> Cc: Javi Merino <javi.merino@arm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1442928123-13824-1-git-send-email-kapileshwar.singh@arm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | tools lib api cpu: Introduce cpu.[ch] to obtain cpu related informationArnaldo Carvalho de Melo2015-09-143-0/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | E.g.: $ ./cpu__get_max_freq 3200000 It does that, as Kan's patch does, by looking at these files: $ cat /sys/devices/system/cpu/online 0-3 $ ./sysfs__read_ull devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq=3200000 $ I.e. find out the first online CPU, then read its cpufreq info. But do it in tools/lib/api/, so that other tools/ living code can use it, not just perf. Based-on-a-patch-by: Kan Liang <kan.liang@intel.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Stephane Eranian <eranian@google.com> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-915v4cvxqplaub8qco66b9mv@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | tools lib api fs: Introduce sysfs__read_{int,ull}()Arnaldo Carvalho de Melo2015-09-142-0/+49
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To read either an int or an unsigned long long value from the given file. E.g.: $ cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq 3200000 $ ./sysfs__read_ull devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq=3200000 $ Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Stephane Eranian <eranian@google.com> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-4a12m4d5k8m4qgc1vguocvei@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | tools lib api fs: Remove debugfs, tracefs and findfs objectsJiri Olsa2015-09-147-288/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have all the functionality in fs.c, let's remove unneeded objects. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Raphael Beamonte <raphael.beamonte@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1441180605-24737-15-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | tools lib api fs: Replace debugfs/tracefs objects interface with fs.cJiri Olsa2015-09-142-9/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Switching to the fs.c related filesystem framework. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Raphael Beamonte <raphael.beamonte@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1441180605-24737-14-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | tools lib api fs: Make tracing_path_strerror_open message genericJiri Olsa2015-09-141-10/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Making tracing_path__strerror_open_tp message generic by mentioning both debugfs/tracefs words in error message plus the tracing_path instead of debugfs_mountpoint. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Raphael Beamonte <raphael.beamonte@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1441180605-24737-7-git-send-email-jolsa@kernel.org [ Add comment for the ENOENT case out of this patch discussion thread ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | tools lib api fs: Add FSTYPE__configured() methodJiri Olsa2015-09-042-10/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add FSTYPE__configured() (where FSTYPE is one of sysfs, procfs, debugfs, tracefs) interface that returns bool state of the filesystem mount: true - mounted, false - not mounted It will not try to mount the filesystem. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Raphael Beamonte <raphael.beamonte@gmail.com> Cc: David Ahern <dsahern@gmail.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1441180605-24737-13-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | tools lib api fs: Add FSTYPE__mount() methodJiri Olsa2015-09-042-9/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adding FSTYPE__mount (where FSTYPE is, as of now, one of sysfs, procfs, debugfs, tracefs) method that tries to mount the filesystem in case no mount of FSTYPE is found. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Raphael Beamonte <raphael.beamonte@gmail.com> Cc: David Ahern <dsahern@gmail.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1441180605-24737-12-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | tools lib api fs: Add tracefs into fs.c objectJiri Olsa2015-09-042-0/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adding tracefs support into fs.c framework. It'll replace the tracefs object functionality in following patches. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Raphael Beamonte <raphael.beamonte@gmail.com> Cc: David Ahern <dsahern@gmail.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1441180605-24737-11-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | tools lib api fs: Add debugfs into fs.c objectJiri Olsa2015-09-042-6/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adding debugfs support into fs.c framework. It'll replace the debugfs object functionality in following patches. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Raphael Beamonte <raphael.beamonte@gmail.com> Cc: David Ahern <dsahern@gmail.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1441180605-24737-10-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | tools lib api fs: Move SYSFS_MAGIC PROC_SUPER_MAGIC into fs.cJiri Olsa2015-09-042-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's no need to export SYSFS_MAGIC PROC_SUPER_MAGIC in fs.h. Leave them in the fs.c. Link: http://lkml.kernel.org/n/tip-b2cd1bb7yvbazq5oua24oz18@git.kernel.org Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Raphael Beamonte <raphael.beamonte@gmail.com> Cc: David Ahern <dsahern@gmail.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1441180605-24737-9-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | tools lib api fs: Add STR and PATH_MAX macros to fs objectJiri Olsa2015-09-042-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We're going to get rid of findfs.h in following patches, but we'll still need these macros. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Raphael Beamonte <raphael.beamonte@gmail.com> Cc: David Ahern <dsahern@gmail.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1441180605-24737-8-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | tools lib api fs: Move debugfs__strerror_open into tracing_path.c objectJiri Olsa2015-09-043-52/+57
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Moving debugfs__strerror_open out of api/fs/debugfs.c, because it's not debugfs specific. It'll be changed to consider tracefs mount as well in following patches. Renaming it into tracing_path__strerror_open_tp to fit into the namespace. No functional change is intended. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Reviewed-by: Matt Fleming <matt.fleming@intel.com> Cc: Raphael Beamonte <raphael.beamonte@gmail.com> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1441180605-24737-6-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | tools lib api fs: Move tracing_path interface into api/fs/tracing_path.cJiri Olsa2015-09-043-0/+97
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Moving tracing_path interface into api/fs/tracing_path.c out of util.c. It seems generic enough to be used by others, and I couldn't think of better place. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Reviewed-by: Matt Fleming <matt.fleming@intel.com> Reviewed-by: Raphael Beamonte <raphael.beamonte@gmail.com> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1441180605-24737-5-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | tools lib traceevent: Support function __get_dynamic_array_lenHe Kuang2015-09-022-2/+55
|/ | | | | | | | | | | | | | | | | | | | | | | | | Support helper function __get_dynamic_array_len() in libtraceevent, this function is used accompany with __print_array() or __print_hex(), but currently it is not an available function in the function list of process_function(). The total allocated length of the dynamic array is embedded in the top half of __data_loc_##item field. This patch adds new arg type PRINT_DYNAMIC_ARRAY_LEN to return the length to eval_num_arg(), Signed-off-by: He Kuang <hekuang@huawei.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Wang Nan <wangnan0@huawei.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1440822125-52691-32-git-send-email-wangnan0@huawei.com Signed-off-by: Wang Nan <wangnan0@huawei.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* Merge tag 'perf-core-for-mingo' of ↵Ingo Molnar2015-09-012-4/+25
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo: User visible changes: - Add ability to specify to select which registers to record, to reduce the size of perf.data files, and also allow printing the registers in 'perf script': (Stephane Eranian) # perf record --intr-regs=AX,SP usleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.016 MB perf.data (8 samples) ] # perf script -F ip,sym,iregs | tail -5 ffffffff8105f42a native_write_msr_safe AX:0xf SP:0xffff8802629c3c00 ffffffff8105f42a native_write_msr_safe AX:0xf SP:0xffff8802629c3c00 ffffffff81761ac0 _raw_spin_lock AX:0xffff8801bfcf8020 SP:0xffff8802629c3ce8 ffffffff81202bf8 __vma_adjust_trans_huge AX:0x7ffc75200000 SP:0xffff8802629c3b30 ffffffff8122b089 dput AX:0x101 SP:0xffff8802629c3c78 # Infrastructure changes: - Open event on evsel cpus and threads. (Kan Liang) - Add new bpf API to get name from a BPF object. (Wang Nan) Build fixes: - Fix build on powerpc broken by pt/bts. (Adrian Hunter) Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * bpf tools: New API to get name from a BPF objectWang Nan2015-08-312-4/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before this patch there's no way to connect a loaded bpf object to its source file. However, during applying perf's '--filter' to BPF object, without this connection makes things harder, because perf loads all programs together, but '--filter' setting is for each object. The API of bpf_object__open_buffer() is changed to allow passing a name. Fortunately, at this time there's only one user of it (perf test LLVM), so we change it together. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1440742821-44548-2-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
* | Merge branch 'perf-core-for-linus' of ↵Linus Torvalds2015-08-3110-3/+1522
|\ \ | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Ingo Molnar: "Main perf kernel side changes: - uprobes updates/fixes. (Oleg Nesterov) - Add PERF_RECORD_SWITCH to indicate context switches and use it in tooling. (Adrian Hunter) - Support BPF programs attached to uprobes and first steps for BPF tooling support. (Wang Nan) - x86 generic x86 MSR-to-perf PMU driver. (Andy Lutomirski) - x86 Intel PT, LBR and BTS updates. (Alexander Shishkin) - x86 Intel Skylake support. (Andi Kleen) - x86 Intel Knights Landing (KNL) RAPL support. (Dasaratharaman Chandramouli) - x86 Intel Broadwell-DE uncore support. (Kan Liang) - x86 hw breakpoints robustization (Andy Lutomirski) Main perf tooling side changes: - Support Intel PT in several tools, enabling the use of the processor trace feature introduced in Intel Broadwell processors: (Adrian Hunter) # dmesg | grep Performance # [0.188477] Performance Events: PEBS fmt2+, 16-deep LBR, Broadwell events, full-width counters, Intel PMU driver. # perf record -e intel_pt//u -a sleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.216 MB perf.data ] # perf script # then navigate in the tool output to some area, like this one: 184 1030 dl_main (/usr/lib64/ld-2.17.so) => 7f21ba661440 dl_main (/usr/lib64/ld-2.17.so) 185 1457 dl_main (/usr/lib64/ld-2.17.so) => 7f21ba669f10 _dl_new_object (/usr/lib64/ld-2.17.so) 186 9f37 _dl_new_object (/usr/lib64/ld-2.17.so) => 7f21ba677b90 strlen (/usr/lib64/ld-2.17.so) 187 7ba3 strlen (/usr/lib64/ld-2.17.so) => 7f21ba677c75 strlen (/usr/lib64/ld-2.17.so) 188 7c78 strlen (/usr/lib64/ld-2.17.so) => 7f21ba669f3c _dl_new_object (/usr/lib64/ld-2.17.so) 189 9f8a _dl_new_object (/usr/lib64/ld-2.17.so) => 7f21ba65fab0 calloc@plt (/usr/lib64/ld-2.17.so) 190 fab0 calloc@plt (/usr/lib64/ld-2.17.so) => 7f21ba675e70 calloc (/usr/lib64/ld-2.17.so) 191 5e87 calloc (/usr/lib64/ld-2.17.so) => 7f21ba65fa90 malloc@plt (/usr/lib64/ld-2.17.so) 192 fa90 malloc@plt (/usr/lib64/ld-2.17.so) => 7f21ba675e60 malloc (/usr/lib64/ld-2.17.so) 193 5e68 malloc (/usr/lib64/ld-2.17.so) => 7f21ba65fa80 __libc_memalign@plt (/usr/lib64/ld-2.17.so) 194 fa80 __libc_memalign@plt (/usr/lib64/ld-2.17.so) => 7f21ba675d50 __libc_memalign (/usr/lib64/ld-2.17.so) 195 5d63 __libc_memalign (/usr/lib64/ld-2.17.so) => 7f21ba675e20 __libc_memalign (/usr/lib64/ld-2.17.so) 196 5e40 __libc_memalign (/usr/lib64/ld-2.17.so) => 7f21ba675d73 __libc_memalign (/usr/lib64/ld-2.17.so) 197 5d97 __libc_memalign (/usr/lib64/ld-2.17.so) => 7f21ba675e18 __libc_memalign (/usr/lib64/ld-2.17.so) 198 5e1e __libc_memalign (/usr/lib64/ld-2.17.so) => 7f21ba675df9 __libc_memalign (/usr/lib64/ld-2.17.so) 199 5e10 __libc_memalign (/usr/lib64/ld-2.17.so) => 7f21ba669f8f _dl_new_object (/usr/lib64/ld-2.17.so) 200 9fc2 _dl_new_object (/usr/lib64/ld-2.17.so) => 7f21ba678e70 memcpy (/usr/lib64/ld-2.17.so) 201 8e8c memcpy (/usr/lib64/ld-2.17.so) => 7f21ba678ea0 memcpy (/usr/lib64/ld-2.17.so) - Add support for using several Intel PT features (CYC, MTC packets), the relevant documentation was updated in: tools/perf/Documentation/intel-pt.txt briefly describing those packets, its purposes, how to configure them in the event config terms and relevant external documentation for further reading. (Adrian Hunter) - Introduce support for probing at an absolute address, for user and kernel 'perf probe's, useful when one have the symbol maps on a developer machine but not on an embedded system. (Wang Nan) - Add Intel BTS support, with a call-graph script to show it and PT in use in a GUI using 'perf script' python scripting with postgresql and Qt. (Adrian Hunter) - Allow selecting the type of callchains per event, including disabling callchains in all but one entry in an event list, to save space, and also to ask for the callchains collected in one event to be used in other events. (Kan Liang) - Beautify more syscall arguments in 'perf trace': (Arnaldo Carvalho de Melo) * A bunch more translate file/pathnames from pointers to strings. * Convert numbers to strings for the 'keyctl' syscall 'option' arg. * Add missing 'clockid' entries. - Introduce 'srcfile' sort key: (Andi Kleen) # perf record -F 10000 usleep 1 # perf report --stdio --dsos '[kernel.vmlinux]' -s srcfile <SNIP> # Overhead Source File 26.49% copy_page_64.S 5.49% signal.c 0.51% msr.h # It can be combined with other fields, for instance, experiment with '-s srcfile,symbol'. There are some oddities in some distros and with some specific DSOs, being investigated, so your mileage may vary. - Support per-event 'freq' term: (Namhyung Kim) $ perf record -e 'cpu/instructions,freq=1234/',cycles -c 1000 sleep 1 $ perf evlist -F cpu/instructions,freq=1234/: sample_freq=1234 cycles: sample_period=1000 $ - Deref sys_enter pointer args with contents from probe:vfs_getname, showing pathnames instead of pointers in many syscalls in 'perf trace'. (Arnaldo Carvalho de Melo) - Stop collecting /proc/kallsyms in perf.data files, saving about 4.5MB on a typical x86-64 system, use the the symbol resolution routines used in all the other tools (report, top, etc) now that we can ask libtraceevent to use perf's symbol resolution code. (Arnaldo Carvalho de Melo) - Allow filtering out of perf's PID via 'perf record --exclude-perf'. (Wang Nan) - 'perf trace' now supports syscall groups, like strace, i.e: $ trace -e file touch file Will expand 'file' into multiple, file related, syscalls. More work needed to add extra groups for other syscall groups, and also to complement what was added for the 'file' group, included as a proof of concept. (Arnaldo Carvalho de Melo) - Add lock_pi stresser to 'perf bench futex', to test the kernel code related to FUTEX_(UN)LOCK_PI. (Davidlohr Bueso) - Let user have timestamps with per-thread recording in 'perf record' (Adrian Hunter) - ... and tons of other changes, see the shortlog and the Git log for details" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (240 commits) perf evlist: Add backpointer for perf_env to evlist perf tools: Rename perf_session_env to perf_env perf tools: Do not change lib/api/fs/debugfs directly perf tools: Add tracing_path and remove unneeded functions perf buildid: Introduce sysfs/filename__sprintf_build_id perf evsel: Add a backpointer to the evlist a evsel is in perf trace: Add header with copyright and background info perf scripts python: Add new compaction-times script perf stat: Get correct cpu id for print_aggr tools lib traceeveent: Allow for negative numbers in print format perf script: Add --[no-]-demangle/--[no-]-demangle-kernel tracing/uprobes: Do not print '0x (null)' when offset is 0 perf probe: Support probing at absolute address perf probe: Fix error reported when offset without function perf probe: Fix list result when address is zero perf probe: Fix list result when symbol can't be found tools build: Allow duplicate objects in the object list perf tools: Remove export.h from MANIFEST perf probe: Prevent segfault when reading probe point with absolute address perf tools: Update Intel PT documentation ...
| * tools lib traceeveent: Allow for negative numbers in print formatSteven Rostedt2015-08-281-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It was reported that "%-8s" does not parse well when used in the printk format. The '-' is what is throwing it off. Allow that to be included. Reporter note: Example before: transhuge-stres-10730 [004] 5897.713989: mm_compaction_finished: node=0 zone=>-<8s order=-2119871790 ret= Example after: transhuge-stres-4235 [000] 453.149280: mm_compaction_finished: node=0 zone=ffffffff81815d7a order=9 ret= (I will send patches to fix the string handling in the tracepoints so it's on par with in-kernel printing via trace_pipe:) transhuge-stres-10921 [007] ...1 6307.140205: mm_compaction_finished: node=0 zone=Normal order=9 ret=partial Reported-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Tested-by: Vlastimil Babka <vbabka@suse.cz> Cc: Namhyung Kim <namhyung@kernel.org> Link: http://lkml.kernel.org/r/20150827094601.46518bcc@gandalf.local.home Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * tools lib traceevent: Add checks for returned EVENT_ERROR typeDean Nelson2015-08-211-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Running the following perf-stat command on an arm64 system produces the following result... [root@aarch64 ~]# perf stat -e kmem:mm_page_alloc -a sleep 1 Warning: [kmem:mm_page_alloc] function sizeof not defined Warning: Error: expected type 4 but read 0 Segmentation fault [root@aarch64 ~]# The second warning was a result of the first warning not stopping processing after it detected the issue. That is, code that found the issue reported the first problem, but because it did not exit out of the functions smoothly, it caused the other warning to appear and not only that, it later caused the SIGSEGV. Signed-off-by: Dean Nelson <dnelson@redhat.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20150820151632.13927.13791.email-sent-by-dnelson@teal Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * bpf tools: Link all bpf objects onto a listWang Nan2015-08-072-0/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To allow enumeration of all bpf_objects, keep them in a list (hidden to caller). bpf_object__for_each_safe() is introduced to do this iteration. It is safe even user close the object during iteration. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1435716878-189507-23-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * bpf tools: Introduce accessors for struct bpf_programWang Nan2015-08-072-0/+96
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces accessors for user of libbpf to retrieve section name and fd of a opened/loaded eBPF program. 'struct bpf_prog_handler' is used for that purpose. Accessors of programs section name and file descriptor are provided. Set/get private data are also impelmented. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Link: http://lkml.kernel.org/r/1435716878-189507-21-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * bpf tools: Load eBPF programs in object files into kernelWang Nan2015-08-071-0/+90
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch utilizes previous introduced bpf_load_program to load programs in the ELF file into kernel. Result is stored in 'fd' field in 'struct bpf_program'. During loading, it allocs a log buffer and free it before return. Note that that buffer is not passed to bpf_load_program() if the first loading try is successful. Doesn't use a statically allocated log buffer to avoid potention multi-thread problem. Instructions collected during opening is cleared after loading. load_program() is created for loading a 'struct bpf_insn' array into kernel, bpf_program__load() calls it. By this design we have a function loads instructions into kernel. It will be used by further patches, which creates different instances from a program and load them into kernel. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1435716878-189507-20-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * bpf tools: Introduce bpf_load_program() to bpf.cWang Nan2015-08-072-0/+41
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | bpf_load_program() can be used to load bpf program into kernel. To make loading faster, first try to load without logbuf. Try again with logbuf if the first try failed. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1435716878-189507-19-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * bpf tools: Relocate eBPF programsWang Nan2015-08-071-0/+52
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If an eBPF program accesses a map, LLVM generates a load instruction which loads an absolute address into a register, like this: ld_64 r1, <MCOperand Expr:(mymap)> ... call 2 That ld_64 instruction will be recorded in relocation section. To enable the usage of that map, relocation must be done by replacing the immediate value by real map file descriptor so it can be found by eBPF map functions. This patch to the relocation work based on information collected by patches: 'bpf tools: Collect symbol table from SHT_SYMTAB section', 'bpf tools: Collect relocation sections from SHT_REL sections' and 'bpf tools: Record map accessing instructions for each program'. For each instruction which needs relocation, it inject corresponding file descriptor to imm field. As a part of protocol, src_reg is set to BPF_PSEUDO_MAP_FD to notify kernel this is a map loading instruction. This is the final part of map relocation patch. The principle of map relocation is described in commit message of 'bpf tools: Collect symbol table from SHT_SYMTAB section'. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1435716878-189507-18-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * bpf tools: Create eBPF maps defined in an object fileWang Nan2015-08-072-0/+106
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch creates maps based on 'map' section in object file using bpf_create_map(), and stores the fds into an array in 'struct bpf_object'. Previous patches parse ELF object file and collects required data, but doesn't play with the kernel. They belong to the 'opening' phase. This patch is the first patch in 'loading' phase. The 'loaded' field is introduced in 'struct bpf_object' to avoid loading an object twice, because the loading phase clears resources collected during the opening which becomes useless after loading. In this patch, maps_buf is cleared. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1435716878-189507-17-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * bpf tools: Add bpf.c/h for common bpf operationsWang Nan2015-08-073-1/+68
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces bpf.c and bpf.h, which hold common functions issuing bpf syscall. The goal of these two files is to hide syscall completely from user. Note that bpf.c and bpf.h deal with kernel interface only. Things like structure of 'map' section in the ELF object is not cared by of bpf.[ch]. We first introduce bpf_create_map(). Note that, since functions in bpf.[ch] are wrapper of sys_bpf, they don't use OO style naming. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1435716878-189507-16-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * bpf tools: Record map accessing instructions for each programWang Nan2015-08-072-0/+137
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch records the indices of instructions which are needed to be relocated. That information is saved in the 'reloc_desc' field in 'struct bpf_program'. In the loading phase (this patch takes effect in the opening phase), the collected instructions will be replaced by map loading instructions. Since we are going to close the ELF file and clear all data at the end of the 'opening' phase, the ELF information will no longer be valid in the 'loading' phase. We have to locate the instructions before maps are loaded, instead of directly modifying the instruction. 'struct bpf_map_def' is introduced in this patch to let us know how many maps are defined in the object. This is the third part of map relocation. The principle of map relocation is described in commit message of 'bpf tools: Collect symbol table from SHT_SYMTAB section'. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1435716878-189507-15-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * bpf tools: Collect relocation sections from SHT_REL sectionsWang Nan2015-08-071-0/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch collects relocation sections into 'struct object'. Such sections are used for connecting maps to bpf programs. 'reloc' field in 'struct bpf_object' is introduced for storing such information. This patch simply store the data into 'reloc' field. Following patch will parse them to know the exact instructions which are needed to be relocated. Note that the collected data will be invalid after ELF object file is closed. This is the second patch related to map relocation. The first one is 'bpf tools: Collect symbol table from SHT_SYMTAB section'. The principle of map relocation is described in its commit message. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1435716878-189507-14-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * bpf tools: Collect eBPF programs from their own sectionsWang Nan2015-08-071-0/+114
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch collects all programs in an object file into an array of 'struct bpf_program' for further processing. That structure is for representing each eBPF program. 'bpf_prog' should be a better name, but it has been used by linux/filter.h. Although it is a kernel space name, I still prefer to call it 'bpf_program' to prevent possible confusion. bpf_object__add_program() creates a new 'struct bpf_program' object. It first init a variable in stack using bpf_program__init(), then if success, enlarges obj->programs array and copy the new object in. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1435716878-189507-13-git-send-email-wangnan0@huawei.com [ Made bpf_object__add_program() propagate the error (-EINVAL or -ENOMEM) ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * bpf tools: Collect symbol table from SHT_SYMTAB sectionWang Nan2015-08-071-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch collects symbols section. This section is useful when linking BPF maps. What 'bpf_map_xxx()' functions actually require are map's file descriptors (and the internal verifier converts fds into pointers to 'struct bpf_map'), which we don't know when compiling. Therefore, we should make compiler generate a 'ldr_64 r1, <imm>' instruction, and fill the 'imm' field with the actual file descriptor when loading in libbpf. BPF programs should be written in this way: struct bpf_map_def SEC("maps") my_map = { .type = BPF_MAP_TYPE_HASH, .key_size = sizeof(unsigned long), .value_size = sizeof(unsigned long), .max_entries = 1000000, }; SEC("my_func=sys_write") int my_func(void *ctx) { ... bpf_map_update_elem(&my_map, &key, &value, BPF_ANY); ... } Compiler should convert '&my_map' into a 'ldr_64, r1, <imm>' instruction, where imm should be the address of 'my_map'. According to the address, libbpf knows which map it actually referenced, and then fills the imm field with the 'fd' of that map created by it. However, since we never really 'link' the object file, the imm field is only a record in relocation section. Therefore libbpf should do the relocation: 1. In relocation section (type == SHT_REL), positions of each such 'ldr_64' instruction are recorded with a reference of an entry in symbol table (SHT_SYMTAB); 2. From records in symbol table we can find the indics of map variables. Libbpf first record SHT_SYMTAB and positions of each instruction which required bu such operation. Then create file descriptor. Finally, after map creation complete, replace the imm field. This is the first patch of BPF map related stuff. It records SHT_SYMTAB into object's efile field for further use. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1435716878-189507-12-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * bpf tools: Collect map definitions from 'maps' sectionWang Nan2015-08-071-0/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If maps are used by eBPF programs, corresponding object file(s) should contain a section named 'map'. Which contains map definitions. This patch copies the data of the whole section. Map data parsing should be acted just before map loading. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1435716878-189507-11-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * bpf tools: Collect version and license from ELF sectionsWang Nan2015-08-071-0/+53
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Expand bpf_obj_elf_collect() to collect license and kernel version information in eBPF object file. eBPF object file should have a section named 'license', which contains a string. It should also have a section named 'version', contains a u32 LINUX_VERSION_CODE. bpf_obj_validate() is introduced to validate object file after loaded. Currently it only check existence of 'version' section. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1435716878-189507-10-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * bpf tools: Iterate over ELF sections to collect informationWang Nan2015-08-071-0/+53
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | bpf_obj_elf_collect() is introduced to iterate over each elf sections to collection information in eBPF object files. This function will futher enhanced to collect license, kernel version, programs, configs and map information. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1435716878-189507-9-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * bpf tools: Check endianness and make libbpf fail earlyWang Nan2015-08-071-0/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Check endianness according to EHDR. Code is taken from tools/perf/util/symbol-elf.c. Libbpf doesn't magically convert missmatched endianness. Even if we swap eBPF instructions to correct byte order, we are unable to deal with endianness in code logical generated by LLVM. Therefore, libbpf should simply reject missmatched ELF object, and let LLVM to create good code. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1435716878-189507-8-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * bpf tools: Read eBPF object from bufferWang Nan2015-08-072-12/+52
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To support dynamic compiling, this patch allows caller to pass a in-memory buffer to libbpf by bpf_object__open_buffer(). libbpf calls elf_memory() to open it as ELF object file. Because __bpf_object__open() collects all required data and won't need that buffer anymore, libbpf uses that buffer directly instead of clone a new buffer. Caller of libbpf can free that buffer or use it do other things after bpf_object__open_buffer() return. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1435716878-189507-7-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * bpf tools: Open eBPF object file and do basic validationWang Nan2015-08-072-0/+166
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch defines basic interface of libbpf. 'struct bpf_object' will be the handler of each object file. Its internal structure is hide to user. eBPF object files are compiled by LLVM as ELF format. In this patch, libelf is used to open those files, read EHDR and do basic validation according to e_type and e_machine. All elf related staffs are grouped together and reside in efile field of 'struct bpf_object'. bpf_object__elf_finish() is introduced to clear it. After all eBPF programs in an object file are loaded, related ELF information is useless. Close the object file and free those memory. The zfree() and zclose() functions are introduced to ensure setting NULL pointers and negative file descriptors after resources are released. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1435716878-189507-6-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| * bpf tools: Allow caller to set printing functionWang Nan2015-08-072-0/+52
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | By libbpf_set_print(), users of libbpf are allowed to register he/she own debug, info and warning printing functions. Libbpf will use those functions to print messages. If not provided, default info and warning printing functions are fprintf(stderr, ...); default debug printing is NULL. This API is designed to be used by perf, enables it to register its own logging functions to make all logs uniform, instead of separated logging level control. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1435716878-189507-5-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>