Nest the rules properly. No change in functionality.
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/n/tip-jjlmizjmhockUs04wqnScnkl@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Nest the rules properly. No change in functionality.
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/n/tip-wwktuHl4Ra5lyrrretkxmxqf@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Nest the rules properly. No change in functionality.
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/n/tip-dDgivr9xtjrof2vmoyOfwxkj@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Use GCC's -MD feature to generate a dependency file for each feature test .c file,
and include that .d file in the config/feature-checks/Makefile.
This allows us to do two things:
- speed up feature tests
- detect removal or changes in build dependencies - including system libraries/headers
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/n/tip-Jfma8pmPnnqzpxjbs3hpgmsj@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Start the split-out of the feature check code by adding a list of features to be
tested, and rules to process that list by building its matching feature-check
file in config/feature-checks/test-<feature>.c.
Add 'hello' as the initial feature.
This structure will allow us to build split-out feature checks in parallel and
thus speed up feature detection dramatically.
No change in functionality: no feature check is used by the build rules yet.
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/n/tip-pixkihgscFaohfFigq5yt9gs@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
. The libaudit test was failing in some systems due to a unescaped newline, fix
it so that the 'trace' tool can be built in such systems.
. Fix installation of libexec components.
. Add default handler for mmap2 events so that tools that don't explicitely
define an MMAP2 handler don't crash, fix from David Ahern.
. Fix to find line information for probe list, from Masami Hiramatsu.
. Set child_pid after perf_evlist__prepare_workload(), fix from Namhyung Kim.
. Fix infinite loop on invalid perf.data file, from Namhyung Kim.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-urgent-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent
Pull perf/urgent fixes from Arnaldo Carvalho de Melo:
* The libaudit test was failing in some systems due to a unescaped newline, fix
it so that the 'trace' tool can be built in such systems.
* Fix installation of libexec components.
* Add default handler for mmap2 events so that tools that don't explicitely
define an MMAP2 handler don't crash, fix from David Ahern.
* Fix to find line information for probe list, from Masami Hiramatsu.
* Set child_pid after perf_evlist__prepare_workload(), fix from Namhyung Kim.
* Fix infinite loop on invalid perf.data file, from Namhyung Kim.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
perf-record updates the header in the perf.data file at termination.
Without this update perf-report (and other processing built-ins) it
caused an infinite loop when perf report (or something like) called.
This is because the algorithm in __perf_session__process_events()
depends on the data_size which is read from file header. Use file size
directly instead in this case to do the best-effort processing.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: David Ahern <dsahern@gmail.com>
Tested-by: Sonny Rao <sonnyrao@chromium.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Sonny Rao <sonnyrao@chromium.org>
Link: http://lkml.kernel.org/r/1380529188-27193-1-git-send-email-namhyung@kernel.org
Signed-off-by: David Ahern <dsahern@gmail.com>
[ Reworded warning as per Ingo Molnar suggestion, replaces 'perf.data'
with session->filename, to precisely identify the data file involved ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Doing a fresh install on a user home directory needs to first make sure
that the ~/libexec/perf-core/ directory is present so that
'perf-archive' like scripts, 'perf test' attr config files and 'perf
script' scripts can be installed.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-z7ryi3r1b9dn9smbfnab0fdc@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix to find the correct (as much as possible) line information for
listing probes. Without this fix, perf probe --list action will show
incorrect line information as below;
probe:getname_flags (on getname_flags@ksrc/linux-3/fs/namei.c)
probe:getname_flags_1 (on getname:-89@x86/include/asm/current.h)
probe:getname_flags_2 (on user_path_at_empty:-2054@x86/include/asm/current.h)
The minus line number is obviously wrong, and current.h is not related
to the probe point. Deeper investigation discovered that there were 2
issues related to this bug, and minor typos too.
The 1st issue is the rack of considering about nested inlined functions,
which causes the wrong (relative) line number.
The 2nd issue is that the dwarf line info is not correct at those
points. It points 14th line of current.h.
Since it seems that the line info includes somewhat unreliable
information, this fixes perf to try to find correct line information
from both of debuginfo and line info as below.
1) Probe address is the entry of a function instance
In this case, the line is set as the function declared line.
2) Probe address is the entry of an expanded inline function block
In this case, the line is set as the function call-site line.
This means that the line number is relative from the entry line
of caller function (which can be an inlined function if nested)
3) Probe address is inside a function instance or an expanded
inline function block
In this case, perf probe queries the line number from lineinfo
and verify the function declared file is same as the file name
queried from lineinfo.
If the file name is different, it is a failure case. The probe
address is shown as symbol+offset.
4) Probe address is not in the any function instance
This is a failure case, the probe address is shown as
symbol+offset.
With this fix, perf probe -l shows correct probe lines as below;
probe:getname_flags (on getname_flags@ksrc/linux-3/fs/namei.c)
probe:getname_flags_1 (on getname:2@ksrc/linux-3/fs/namei.c)
probe:getname_flags_2 (on user_path_at_empty:4@ksrc/linux-3/fs/namei.c)
Changes at v2:
- Fix typos in the function comments. (Thanks to Namhyung Kim)
- Use die_find_top_inlinefunc instead of die_find_inlinefunc_next.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20130930092144.1693.11058.stgit@udc4-manage.rcp.hitachi.co.jp
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In ubuntu systems the libaudit test was always failing due to the
newline in the printf call not being escaped, which somehow didn't
prevented the test from working as expected on other systems, such
as fedora18.
Fix it by removing the newline, as this is just a test, that program is
just a compile test.
The error messages, obtained using 'make V=1':
CHK libaudit
<stdin>: In function ‘main’:
<stdin>:5:9: error: missing terminating " character [-Werror]
<stdin>:5:2: error: missing terminating " character
<stdin>:6:1: error: missing terminating " character [-Werror]
<stdin>:6:1: error: missing terminating " character
<stdin>:7:2: error: expected expression before ‘return’
<stdin>:8:1: error: expected ‘;’ before ‘}’ token
cc1: all warnings being treated as errors
config/Makefile:241: No libaudit.h found, disables 'trace' tool, please install audit-libs-devel or libaudit-dev
After this change the test works as expected in all systems tested and the
'trace' tool is built when the needed devel packages are installed.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-0trw8qs9hafeopc0vj1sicay@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The commit acf2892270 ("perf stat: Use perf_evlist__prepare/
start_workload()") converted to use the function but forgot to update
child_pid. Fix it.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1380531671-28076-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commands that do not implement an mmap2 handler should at least not die
with a segfault when processing files with MMAP2 events.
Signed-off-by: David Ahern <dsahern@gmail.com>
Link: http://lkml.kernel.org/r/1379900700-5186-5-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Haswell always give an extra LBR record after every TSX abort.
Suppress the extra record.
This only works when the abort is visible in the LBR
If the original abort has already left the 16 LBR entries
the extra entry will will stay.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1379688044-14173-7-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add support for recording and displaying the transaction flags.
They are essentially a new sort key. Also display them
in a nice way to the user.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1379688044-14173-6-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Make perf record -j aware of the new in_tx,no_tx,abort_tx branch qualifiers.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1379688044-14173-5-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Extend the perf branch sorting code to support sorting by in_tx
or abort_tx qualifiers. Also print out those qualifiers.
This also fixes up some of the existing sort key documentation.
We do not support no_tx here, because it's simply not showing
the in_tx flag.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1379688044-14173-4-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In the PEBS handler report the transaction flags using the new
generic transaction flags facility. Most of them come from
the "tsx_tuning" field in PEBSv2, but the abort code is derived
from the RAX register reported in the PEBS record.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1379688044-14173-3-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add a generic qualifier for transaction events, as a new sample
type that returns a flag word. This is particularly useful
for qualifying aborts: to distinguish aborts which happen
due to asynchronous events (like conflicts caused by another
CPU) versus instructions that lead to an abort.
The tuning strategies are very different for those cases,
so it's important to distinguish them easily and early.
Since it's inconvenient and inflexible to filter for this
in the kernel we report all the events out and allow
some post processing in user space.
The flags are based on the Intel TSX events, but should be fairly
generic and mostly applicable to other HTM architectures too. In addition
to various flag words there's also reserved space to report an
program supplied abort code. For TSX this is used to distinguish specific
classes of aborts, like a lock busy abort when doing lock elision.
Flags:
Elision and generic transactions (ELISION vs TRANSACTION)
(HLE vs RTM on TSX; IBM etc. would likely only use TRANSACTION)
Aborts caused by current thread vs aborts caused by others (SYNC vs ASYNC)
Retryable transaction (RETRY)
Conflicts with other threads (CONFLICT)
Transaction write capacity overflow (CAPACITY WRITE)
Transaction read capacity overflow (CAPACITY READ)
Transactions implicitely aborted can also return an abort code.
This can be used to signal specific events to the profiler. A common
case is abort on lock busy in a RTM eliding library (code 0xff)
To handle this case we include the TSX abort code
Common example aborts in TSX would be:
- Data conflict with another thread on memory read.
Flags: TRANSACTION|ASYNC|CONFLICT
- executing a WRMSR in a transaction. Flags: TRANSACTION|SYNC
- HLE transaction in user space is too large
Flags: ELISION|SYNC|CAPACITY-WRITE
The only flag that is somewhat TSX specific is ELISION.
This adds the perf core glue needed for reporting the new flag word out.
v2: Add MEM/MISC
v3: Move transaction to the end
v4: Separate capacity-read/write and remove misc
v5: Remove _SAMPLE. Move abort flags to 32bit. Rename
transaction to txn
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1379688044-14173-2-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add support to perf stat to print the basic transactional execution statistics:
Total cycles, Cycles in Transaction, Cycles in aborted transsactions
using the in_tx and in_tx_checkpoint qualifiers.
Transaction Starts and Elision Starts, to compute the average transaction
length.
This is a reasonable overview over the success of the transactions.
Also support architectures that have a transaction aborted cycles
counter like POWER8. Since that is awkward to handle in the kernel
abstract handle both cases here.
Enable with a new --transaction / -T option.
This requires measuring these events in a group, since they depend on each
other.
This is implemented by using TM sysfs events exported by the kernel
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Arnaldo Carvalho de Melo <acme@infradead.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1377128846-977-5-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
/proc/sys/kernel/perf_event_max_sample_rate will accept
negative values as well as 0.
Negative values are unreasonable, and 0 causes a
divide by zero exception in perf_proc_update_handler.
This patch enforces a lower limit of 1.
Signed-off-by: Knut Petersen <Knut_Petersen@t-online.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/5242DB0C.4070005@t-online.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Some of the node comparisons in hist.c dropped the upper
32bit by using an int variable to store the compare
result. This broke various 64bit fields, causing
incorrect collapsing (found for the TSX transaction field)
Just use int64_t always.
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1380637335-30110-1-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently the cap_user_time_zero capability has different tests than
cap_user_time; even though they expose the exact same data.
Switch from CONSTANT && NONSTOP to sched_clock_stable to also deal
with multi cabinet machines and drop the tsc_disabled() check.. non of
this will work sanely without tsc anyway.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-nmgn0j0muo1r4c94vlfh23xy@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While auditing the list_entry usage due to a trinity bug I found that
perf_pmu_migrate_context violates the rules for
perf_event::event_entry.
The problem is that perf_event::event_entry is a RCU list element, and
hence we must wait for a full RCU grace period before re-using the
element after deletion.
Therefore the usage in perf_pmu_migrate_context() which re-uses the
entry immediately is broken. For now introduce another list_head into
perf_event for this specific usage.
This doesn't actually fix the trinity report because that never goes
through this code.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-mkj72lxagw1z8fvjm648iznw@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull drm fixes from Dave Airlie:
"Nothing too major, radeon still has some dpm changes for off by
default.
Radeon, intel, msm:
- radeon: a few more dpm fixes (still off by default), uvd fixes
- i915: runtime warn backtrace and regression fix
- msm: iommu changes fallout"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (27 commits)
drm/msm: use drm_gem_dumb_destroy helper
drm/msm: deal with mach/iommu.h removal
drm/msm: Remove iommu include from mdp4_kms.c
drm/msm: Odd PTR_ERR usage
drm/i915: Fix up usage of SHRINK_STOP
drm/radeon: fix hdmi audio on DCE3.0/3.1 asics
drm/i915: preserve pipe A quirk in i9xx_set_pipeconf
drm/i915/tv: clear adjusted_mode.flags
drm/i915/dp: increase i2c-over-aux retry interval on AUX DEFER
drm/radeon/cik: fix overflow in vram fetch
drm/radeon: add missing hdmi callbacks for rv6xx
drm/i915: Use a temporary va_list for two-pass string handling
drm/radeon/uvd: lower msg&fb buffer requirements on UVD3
drm/radeon: disable tests/benchmarks if accel is disabled
drm/radeon: don't set default clocks for SI when DPM is disabled
drm/radeon/dpm/ci: filter clocks based on voltage/clk dep tables
drm/radeon/dpm/si: filter clocks based on voltage/clk dep tables
drm/radeon/dpm/ni: filter clocks based on voltage/clk dep tables
drm/radeon/dpm/btc: filter clocks based on voltage/clk dep tables
drm/radeon/dpm: fetch the max clk from voltage dep tables helper
...
This reverts commit de95ab5364.
Markus Trippelsdorf reported that this commit broke 'perf top':
> I just see a gray screen with no text at all. Sometimes the
> following error messages are printed:
>
> *** Error in `perf': invalid fastbin entry (free): 0x00000000029b18c0
> ***
> *** Error in `perf': malloc(): memory corruption (fast): 0x0000000000ee0b10 ***
While this code is fixable, the commit itself fails on several levels:
- it should have been a separate helper function
- why the heck does it do strchr() twice
- it casts a const char * over into char *
- sloppy style
- it's not even a regression fix!
So lets revert it and re-try the patch in v3.13.
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ingo Molnar
Namhyung Kim
Arnaldo Carvalho de Melo
Masami Hiramatsu
David Ahern
Andi Kleen
Knut Petersen
Peter Zijlstra
Linus Torvalds