So that we can use -T == --timestamp, asking for PERF_SAMPLE_TIME:

  $ perf record -aT
  $ perf report -D | grep PERF_RECORD_
  <SNIP>
   3   5951915425 0x47530 [0x58]: PERF_RECORD_SAMPLE(IP, 1): 16811/16811: 0xffffffff8138c1a2 period: 215979 cpu:3
   3   5952026879 0x47588 [0x90]: PERF_RECORD_SAMPLE(IP, 1): 16811/16811: 0xffffffff810cb480 period: 215979 cpu:3
   3   5952059959 0x47618 [0x38]: PERF_RECORD_FORK(6853:6853):(16811:16811)
   3   5952138878 0x47650 [0x78]: PERF_RECORD_SAMPLE(IP, 1): 16811/16811: 0xffffffff811bac35 period: 431478 cpu:3
   3   5952375068 0x476c8 [0x30]: PERF_RECORD_COMM: find:6853
   3   5952395923 0x476f8 [0x50]: PERF_RECORD_MMAP 6853/6853: [0x400000(0x25000) @ 0]: /usr/bin/find
   3   5952413756 0x47748 [0xa0]: PERF_RECORD_SAMPLE(IP, 1): 6853/6853: 0xffffffff810d080f period: 859332 cpu:3
   3   5952419837 0x477e8 [0x58]: PERF_RECORD_MMAP 6853/6853: [0x3f44600000(0x21d000) @ 0]: /lib64/ld-2.5.so
   3   5952437929 0x47840 [0x48]: PERF_RECORD_MMAP 6853/6853: [0x7fff7e1c9000(0x1000) @ 0x7fff7e1c9000]: [vdso]
   3   5952570127 0x47888 [0x58]: PERF_RECORD_MMAP 6853/6853: [0x3f46200000(0x218000) @ 0]: /lib64/libselinux.so.1
   3   5952623637 0x478e0 [0x58]: PERF_RECORD_MMAP 6853/6853: [0x3f44a00000(0x356000) @ 0]: /lib64/libc-2.5.so
   3   5952675720 0x47938 [0x58]: PERF_RECORD_MMAP 6853/6853: [0x3f44e00000(0x204000) @ 0]: /lib64/libdl-2.5.so
   3   5952710080 0x47990 [0x58]: PERF_RECORD_MMAP 6853/6853: [0x3f45a00000(0x246000) @ 0]: /lib64/libsepol.so.1
   3   5952847802 0x479e8 [0x58]: PERF_RECORD_SAMPLE(IP, 1): 6853/6853: 0xffffffff813897f0 period: 1142536 cpu:3
  <SNIP>

First column is the cpu and the second the timestamp.

That way we can investigate problems in the event stream.

If the new perf binary is run on an older kernel, it will disable this feature
automatically.
Tested-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NIan Munsie <imunsie@au1.ibm.com>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Ian Munsie <imunsie@au1.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <1291318772-30880-5-git-send-email-acme@infradead.org>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

At perf_session__process_event, so that we reduce the number of lines in eache
tool sample processing routine that now receives a sample_data pointer already
parsed.

This will also be useful in the next patch, where we'll allow sample the
identity fields in MMAP, FORK, EXIT, etc, when it will be possible to see (cpu,
timestamp) just after before every event.

Also validate callchains in perf_session__process_event, i.e. as early as
possible, and keep a counter of the number of events discarded due to invalid
callchains, warning the user about it if it happens.

There is an assumption that was kept that all events have the same sample_type,
that will be dealt with in the future, when this preexisting limitation will be
removed.
Tested-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NIan Munsie <imunsie@au1.ibm.com>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Ian Munsie <imunsie@au1.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <1291318772-30880-4-git-send-email-acme@infradead.org>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Collecting build-ids for long running sessions may take a long time
because it needs to traverse the whole just collected perf.data stream
of events, marking the DSOs that had hits and then looking for the
.note.gnu.build-id ELF section.

For things like the 'trace' tool that records and right away consumes
the data on systems where its unlikely that the DSOs being monitored
will change while 'trace' runs, it is desirable to remove build id
collection, so add a -B/--no-buildid option to perf record to allow such
use case.

Longer term we'll avoid all this if we, at DSO load time, in the kernel,
take advantage of this slow code path to collect the build-id and stash
it somewhere, so that we can insert it in the PERF_RECORD_MMAP event.
Reported-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The 59365d13 commit, even being reverted by 33e0d57f, showed a non robust
behavior in 'perf record': it really should just warn the user that some
functionality will not be available.

The new behavior then becomes:

	[acme@felicio linux]$ ls -la /proc/{kallsyms,modules}
	-r-------- 1 root root 0 Nov 22 12:19 /proc/kallsyms
	-r-------- 1 root root 0 Nov 22 12:19 /proc/modules
	[acme@felicio linux]$ perf record ls -R > /dev/null
	Couldn't record kernel reference relocation symbol
	Symbol resolution may be skewed if relocation was used (e.g. kexec).
	Check /proc/kallsyms permission or run as root.
	[ perf record: Woken up 1 times to write data ]
	[ perf record: Captured and wrote 0.004 MB perf.data (~161 samples) ]
	[acme@felicio linux]$ perf report --stdio
	[kernel.kallsyms] with build id 77b05e00e64e4de1c9347d83879779b540d69f00 not found, continuing without symbols
	# Events: 98  cycles
	#
	# Overhead  Command    Shared Object                Symbol
	# ........  .......  ...............  ....................
	#
	    48.26%       ls  [kernel]         [k] ffffffff8102b92b
	    22.49%       ls  libc-2.12.90.so  [.] __strlen_sse2
	     8.35%       ls  libc-2.12.90.so  [.] __GI___strcoll_l
	     8.17%       ls  ls               [.]            11580
	     3.35%       ls  libc-2.12.90.so  [.] _IO_new_file_xsputn
	     3.33%       ls  libc-2.12.90.so  [.] _int_malloc
	     1.88%       ls  libc-2.12.90.so  [.] _int_free
	     0.84%       ls  libc-2.12.90.so  [.] malloc_consolidate
	     0.84%       ls  libc-2.12.90.so  [.] __readdir64
	     0.83%       ls  ls               [.] strlen@plt
	     0.83%       ls  libc-2.12.90.so  [.] __GI_fwrite_unlocked
	     0.83%       ls  libc-2.12.90.so  [.] __memcpy_sse2

	#
	# (For a higher level overview, try: perf report --sort comm,dso)
	#
[acme@felicio linux]$

It still has the build-ids for DSOs in the maps with hits:

[acme@felicio linux]$ perf buildid-list
77b05e00e64e4de1c9347d83879779b540d69f00 [kernel.kallsyms]
09c4a431a4a8b648fcfc2c2bdda70f56050ddff1 /bin/ls
af75ea9ad951d25e0f038901a11b3846dccb29a4 /lib64/libc-2.12.90.so
[acme@felicio linux]$

That can be used in another machine to resolve kernel symbols.

Cc: Eugene Teo <eugeneteo@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jesper Juhl <jj@chaosbits.net>
Cc: Marcus Meissner <meissner@suse.de>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This patch makes several changes to "perf stat":

- "perf stat" will no longer go ahead and run the application when one or
more of the specified events could not be opened.
- Use error() and die() instead of pr_err() so that the output is more
consistent with "perf top" and "perf record".
- Handle permission errors in a more robust way, and in a similar way to
"perf record" and "perf top".

In addition, the sys_perf_event_open() error handling of "perf top" and "perf
record" is made more consistent and adds the following phrase when an event
doesn't open (with something ther than an access or permission error):

"/bin/dmesg may provide additional information."

This is added because kernel code doesn't have a good way of expressing
detailed errors to user space, so its only avenue is to use printk's.  However,
many users may not think of looking at dmesg to find out why an event is being
rejected.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <fweisbec@gmail.com>
Cc: Ian Munsie <ianmunsi@au1.ibm.com>
Cc: Michael Ellerman <michaele@au1.ibm.com>
LKML-Reference: <1290217044-26293-1-git-send-email-cjashfor@linux.vnet.ibm.com>
Signed-off-by: NCorey Ashford <cjashfor@linux.vnet.ibm.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Other perf commands that invoke perf record, such as perf trace, may
want to reuse the options used by perf record.

This makes them non-static and renames them to avoid clashes with
other 'options' variables.
Signed-off-by: NTom Zanussi <tom.zanussi@linux.intel.com>
Acked-by: NArnaldo Carvalho de Melo <acme@ghostprotocols.net>

We want just the script output, not internal details about the record phase.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

If we include a newline character in the string argument to perror()
then the output will be split across two lines like so,

    Unable to read perf file descriptor
    : No space left on device

Deleting the newline character prints a much more readable error,

    Unable to read perf file descriptor: No space left on device

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <89e77b54659bc3798b23a5596c2debb7f6f4cf27.1283010281.git.matt@console-pimps.org>
Signed-off-by: NMatt Fleming <matt@console-pimps.org>
Signed-off-by: NArnaldo Carvalho de Melo <acme@felicio.ghostprotocols.net>

So that we reduce the noise when looking for leaks using tools such as
valgrind.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <new-submission>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

So that we can reduce the noise on valgrind when looking for memory
leaks.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <new-submission>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

guest_kallsyms is redundant here, remove it.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Yanmin Zhang <yanmin_zhang@linux.intel.com>
LKML-Reference: <4C241140.9090008@cn.fujitsu.com>
Signed-off-by: NGui Jianfeng <guijianfeng@cn.fujitsu.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

At exit, perf record will kill the process it was profiling by sending a
SIGTERM to child_pid (if it had been initialised), but in certain situations
child_pid may be 0 and perf would mistakenly kill more processes than intended.

child_pid is set to the return of fork() to either 0 or the pid of the child.
Ordinarily this would not present an issue as the child calls execvp to spawn
the process to be profiled and would therefore never run it's sig_atexit and
never attempt to kill pid 0.

However, if a nonexistant binary had been passed in to perf record the call to
execvp would fail and child_pid would be left set to 0. The child would then
exit and it's atexit handler, finding that child_pid was initialised to 0,
would call kill(0, SIGTERM), resulting in every process within it's process
group being killed.

In the case that perf was being run directly from the shell this typically
would not be an issue as the shell isolates the process.  However, if perf was
being called from another program it could kill unexpected processes, which may
even include X.

This patch changes the logic of the test for whether child_pid was initialised
to only consider positive pids as valid, thereby never attempting to kill pid
0.

Cc: David S. Miller <davem@davemloft.net>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <1276072680-17378-1-git-send-email-imunsie@au1.ibm.com>
Signed-off-by: NIan Munsie <imunsie@au1.ibm.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

There are situations where there is enough information in the perf.data
to process the samples. Updating the buildid cache may add unecessary
overhead in terms of disk space and time (copying large elf images).

A persistent option to do this already exists via the perfconfig file,
simply do:

[buildid]
dir = /dev/null

This patch provides a way to suppress builid cache updates on a per-run
basis.  It addds a new option, -N, to perf record. Buildids are still
generated in the perf.data file.

Cc: David S. Miller <davem@davemloft.net>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4c19ef89.93ecd80a.40dc.fffff8e9@mx.google.com>
Signed-off-by: NStephane Eranian <eranian@google.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

A bug was introduced by commit c45c6ea2.

Perf record was scanning /proc/PID to create synthetic PERF_RECOR_MMAP
entries even though it was running in per-thread mode. There was a bogus
check to select what mmaps to synthesize. We only need all processes in
system-wide mode.

Cc: David S. Miller <davem@davemloft.net>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <4c192107.4f1ee30a.4316.fffff98e@mx.google.com>
Signed-off-by: NStephane Eranian <eranian@google.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add the capacility to track data mmap()s. This can be used together
with PERF_SAMPLE_ADDR for data profiling.
Signed-off-by: NAnton Blanchard <anton@samba.org>
[Updated code for stable perf ABI]
Signed-off-by: NEric B Munson <ebmunson@us.ibm.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1274193049-25997-1-git-send-email-ebmunson@us.ibm.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

In a shared multi-core environment, users want to analyze why their
program was slow. In particular, if the code ran slower only on certain
CPUs due to interference from other programs or kernel threads, the user
should be able to notice that.

Sample usage:

perf record -f -a -- sleep 3
perf report --sort cpu,comm

Workload:

program is running on 16 CPUs
Experiencing interference from an antagonist only on 4 CPUs.

  Samples: 106218177676 cycles

  Overhead  CPU          Command
  ........  ...  ...............

     6.25%  2            program
     6.24%  6            program
     6.24%  11           program
     6.24%  5            program
     6.24%  9            program
     6.24%  10           program
     6.23%  15           program
     6.23%  7            program
     6.23%  3            program
     6.23%  14           program
     6.22%  1            program
     6.20%  13           program
     3.17%  12           program
     3.15%  8            program
     3.14%  0            program
     3.13%  4            program
     3.11%  4         antagonist
     3.11%  0         antagonist
     3.10%  8         antagonist
     3.07%  12        antagonist

Cc: David S. Miller <davem@davemloft.net>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <20100505181612.GA5091@sharma-home.net>
Signed-off-by: NArun Sharma <aruns@google.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This patch adds a -C option to stat, record, top to designate a list of CPUs to
monitor. CPUs can be specified as a comma-separated list or ranges, no space
allowed.

Examples:
$ perf record -a -C0-1,4-7 sleep 1
$ perf top -C0-4
$ perf stat -a -C1,2,3,4 sleep 1

With perf record in per-thread mode with inherit mode on, samples are collected
only when the thread runs on the designated CPUs.

The -C option does not turn on system-wide mode automatically.

Cc: David S. Miller <davem@davemloft.net>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <4bff9496.d345d80a.41fe.7b00@mx.google.com>
Signed-off-by: NStephane Eranian <eranian@google.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When forking the child to be traced, we should check the correct
return value from fork() and not a local variable which is otherwise
unused.
Signed-off-by: NBorislav Petkov <bp@alien8.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <20100531211818.GA30175@liondog.tnic>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>

It seems a waste of space to create a buffer per
event, share it per-cpu.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20100521090710.634824884@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Since it is not allowed to create cross-cpu (or
cross-task) buffers, this option is no longer valid.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20100521090710.582740993@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Perf record repeatedly calls gettimeofday() which adds noise to the performance
measurements.  Since gettimeofday() is only used for the error printf, delete
it.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <20100518225240.GC25589@sgi.com>
Signed-off-by: NRuss Anderson <rja@sgi.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Without the bloated cplus_demangle from binutils, i.e building with:

$ make NO_DEMANGLE=1 O=~acme/git/build/perf -j3 -C tools/perf/ install

Before:

   text	   data	    bss	    dec	    hex	filename
 471851	  29280	4025056	4526187	 45106b	/home/acme/bin/perf

After:

[acme@doppio linux-2.6-tip]$ size ~/bin/perf
   text	   data	    bss	    dec	    hex	filename
 446886	  29232	4008576	4484694	 446e56	/home/acme/bin/perf

So its a 5.3% size reduction in code, but the interesting part is in the git
diff --stat output:

 19 files changed, 20 insertions(+), 1909 deletions(-)

If we ever need some of the things we got from git but weren't using, we just
have to go to the git repo and get fresh, uptodate source code bits.

Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To avoid problems like the one fixed by Stephane Eranian in 3de29cab, now
we'll got this instead:

	bench/sched-messaging.c:259: error: negative width in bit-field ‘<anonymous>’
	bench/sched-messaging.c:261: error: negative width in bit-field ‘<anonymous>’

Which is rather cryptic, but is how BUILD_BUG_ON_ZERO works, so kernel
hackers should be already used to this.

With it in place found some problems, fixed by changing the affected
variables to sensible types or changed some OPT_INTEGER to OPT_UINTEGER.

Next csets will go thru converting each of the remaining OPT_ so that
review can be made easier by grouping changes per type per patch.

Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The -c option defines the user requested sampling period. It was implemented
using an unsigned int variable but the type of the option was OPT_LONG. Thus,
the option parser was overwriting memory belonging to other variables, namely
the mmap_pages leading to a zero page sampling buffer. The bug was exposed only
when compiling at -O0, probably because the compiler was padding variables at
higher optimization levels.

This patch fixes this problem by declaring user_interval as u64. This also
avoids wrap-around issues for large period on 32-bit systems.

Commiter note:

Made it use OPT_U64(user_interval) after implementing OPT_U64 in the
previous patch.

Cc: David S. Miller <davem@davemloft.net>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4bf11ae9.e88cd80a.06b0.ffffa8e3@mx.google.com>
Signed-off-by: NStephane Eranian <eranian@google.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

By default, event inheritance across fork and pthread_create was on but the -i
option of stat and record, which enabled inheritance, led to believe it was off
by default.

This patch fixes this logic by inverting the meaning of the -i option.  By
default inheritance is on whether you attach to a process (-p), a thread (-t)
or start a process. If you pass -i, then you turn off inheritance. Turning off
inheritance if you don't need it, helps limit perf resource usage as well.

The patch also fixes perf stat -t xxxx and perf record -t xxxx which did not
start the counters.
Acked-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4bea9d2f.d60ce30a.0b5b.08e1@mx.google.com>
Signed-off-by: NStephane Eranian <eranian@google.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Usually "_text" is enough, but I received reports that its not always
available, so fallback to "_stext" for the symbol we use to check if we
need to apply any relocation to all the symbols in the kernel symtab,
for when, for instance, kexec is being used.
Reported-by: NDarren Hart <dvhltc@us.ibm.com>
Reported-by: NSteven Rostedt <rostedt@goodmis.org>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

In order to provide a more rubust and deterministic reordering
algorithm, we need to know when we reach a point where we just
did a pass through over every counter buffers to read every thing
they had.

This patch introduces a new PERF_RECORD_FINISHED_ROUND pseudo event
that only consist in an event header and doesn't need to contain
anything.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>

Fix a couple of inefficiencies and redundancies related to
have_tracepoints() and its use when checking whether to write
TRACE_INFO.

First, there's no need to use get_tracepoints_path() in
have_tracepoints() - we really just want the part that checks whether
any attributes correspondo to tracepoints.

Second, we really don't care about raw_samples per se - tracepoints
are always raw_samples.  In any case, the have_tracepoints() check
should be sufficient to decide whether or not to write TRACE_INFO.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>,
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: NFrederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1273030770.6383.6.camel@tropicana>
Signed-off-by: NTom Zanussi <tzanussi@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The current perf code implicitly assumes SAMPLE_RAW means tracepoints
are being used, but doesn't check for that.  It happily records the
TRACE_INFO even if SAMPLE_RAW is used without tracepoints, but when the
perf data is read it won't go any further when it finds TRACE_INFO but
no tracepoints, and displays misleading errors.

This adds a check for both in perf-record, and won't record TRACE_INFO
unless both are true.  This at least allows perf report -D to dump raw
events, and avoids triggering a misleading error condition in perf
trace.  It doesn't actually enable the non-tracepoint raw events to be
displayed in perf trace, since perf trace currently only deals with
tracepoint events.

Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1272865861.7932.16.camel@tropicana>
Signed-off-by: NTom Zanussi <tzanussi@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

With this I was able to actually test Tom Zanussi's two previous patches
in my usual perf testing ways, i.e. without any tracepoints activated.

Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Currently, perf 'live mode' writes build-ids at the end of the
session, which isn't actually useful for processing live mode events.

What would be better would be to have the build-ids sent before any of
the samples that reference them, which can be done by processing the
event stream and retrieving the build-ids on the first hit.  Doing
that in perf-record itself, however, is off-limits.

This patch introduces perf-inject, which does the same job while
leaving perf-record untouched.  Normal mode perf still records the
build-ids at the end of the session as it should, but for live mode,
perf-inject can be injected in between the record and report steps
e.g.:

perf record -o - ./hackbench 10 | perf inject -v -b | perf report -v -i -

perf-inject reads a perf-record event stream and repipes it to stdout.
At any point the processing code can inject other events into the
event stream - in this case build-ids (-b option) are read and
injected as needed into the event stream.

Build-ids are just the first user of perf-inject - potentially
anything that needs userspace processing to augment the trace stream
with additional information could make use of this facility.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1272696080-16435-3-git-send-email-tzanussi@gmail.com>
Signed-off-by: NTom Zanussi <tzanussi@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

It doesn't really make sense to record the build ids at the end of a
live mode session - live mode samples need that information during the
trace rather than at the end.

Leave event__synthesize_build_id() in place, however; we'll still be
using that to synthesize build ids in a more timely fashion in a
future patch.

Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1272696080-16435-2-git-send-email-tzanussi@gmail.com>
Signed-off-by: NTom Zanussi <tzanussi@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

struct kernel_info and kerninfo__ are too vague, what they really
describe are machines, virtual ones or hosts.

There are more changes to introduce helpers to shorten function calls
and to make more clear what is really being done, but I left that for
subsequent patches.

Cc: Avi Kivity <avi@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Zhang, Yanmin <yanmin_zhang@linux.intel.com>
LKML-Reference: <new-submission>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Here is the patch of userspace perf tool.
Signed-off-by: NZhang Yanmin <yanmin_zhang@linux.intel.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Trace events are mostly used for tracing and then require not to
be lost when possible. As opposite to hardware events that really
require to trigger after a given sample period, trace events mostly
need to trigger everytime.

It is a frustrating experience to trace with perf and realize we
lost a lot of events because we forgot the "-c 1" option.

Then default sample_period to 1 for trace events but let the user
override it.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>

Force the overwriting mode by default if append mode is not explicit.
Adding -f every time one uses perf on a daily basis quickly becomes a
burden.

Keep the -f among the options though to avoid breaking some random
users scripts.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>

Bypasses the build_id perf header code and replaces it with a
synthesized event and processing function that accomplishes the
same thing, used when reading/writing perf data to/from a pipe.
Signed-off-by: NTom Zanussi <tzanussi@gmail.com>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Cc: fweisbec@gmail.com
Cc: rostedt@goodmis.org
Cc: k-keiichi@bx.jp.nec.com
Cc: acme@ghostprotocols.net
LKML-Reference: <1270184365-8281-9-git-send-email-tzanussi@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Bypasses the tracing_data perf header code and replaces it with
a synthesized event and processing function that accomplishes
the same thing, used when reading/writing perf data to/from a
pipe.

The tracing data is pretty large, and this patch doesn't attempt
to break it down into component events.  The tracing_data event
itself doesn't actually contain the tracing data, rather it
arranges for the event processing code to skip over it after
it's read, using the skip return value added to the event
processing loop in a previous patch.
Signed-off-by: NTom Zanussi <tzanussi@gmail.com>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Cc: fweisbec@gmail.com
Cc: rostedt@goodmis.org
Cc: k-keiichi@bx.jp.nec.com
Cc: acme@ghostprotocols.net
LKML-Reference: <1270184365-8281-8-git-send-email-tzanussi@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Bypasses the event type perf header code and replaces it with a
synthesized event and processing function that accomplishes the
same thing, used when reading/writing perf data to/from a pipe.
Signed-off-by: NTom Zanussi <tzanussi@gmail.com>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Cc: fweisbec@gmail.com
Cc: rostedt@goodmis.org
Cc: k-keiichi@bx.jp.nec.com
Cc: acme@ghostprotocols.net
LKML-Reference: <1270184365-8281-7-git-send-email-tzanussi@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Bypasses the attr perf header code and replaces it with a
synthesized event and processing function that accomplishes the
same thing, used when reading/writing perf data to/from a pipe.

Making the attrs into events allows them to be streamed over a
pipe along with the rest of the header data (in later patches).
It also paves the way to allowing events to be added and removed
from perf sessions dynamically.
Signed-off-by: NTom Zanussi <tzanussi@gmail.com>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Cc: fweisbec@gmail.com
Cc: rostedt@goodmis.org
Cc: k-keiichi@bx.jp.nec.com
Cc: acme@ghostprotocols.net
LKML-Reference: <1270184365-8281-6-git-send-email-tzanussi@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>