Commit Graph

17 Commits

Author SHA1 Message Date
Arnaldo Carvalho de Melo b3c9ac0846 perf callchains: Store the map together with the symbol
We need this to know where a symbol in a callchain came from,
for various reasons, among them precise annotation from a
TUI/GUI tool.

Signed-off-by: Arnaldo Carvalho de Melo <acme@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>
LKML-Reference: <1269459619-982-5-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-26 08:52:57 +01:00
Frederic Weisbecker 301fde27c7 perf: Fix orphan callchain branches
Callchains have markers inside their capture to tell we
enter a context (kernel, user, ...).

Those are not displayed in the callchains but they are
incidentally an active part of the radix tree where
callchains are stored, just like any other address.

If we have the two following callchains:

addr1 -> addr2 -> user context -> addr3
addr1 -> addr2 -> user context -> addr4
addr1 -> addr2 -> addr 5

This is pretty common if addr1 and addr2 are part of an
interrupt path, addr3 and addr4 are user addresses and
addr5 is a kernel non interrupt path.

This will be stored as follows in the tree:

                   addr1
                   addr2
                   /   \
                  /     addr5
            user context
               /    \
             addr3  addr4

But we ignore the context markers in the report, hence
the addr3 and addr4 will appear as orphan branches:

    |--28.30%-- hrtimer_interrupt
    |          smp_apic_timer_interrupt
    |          apic_timer_interrupt
    |          |           <------------- here, no parent!
    |          |          |
    |          |          |--11.11%-- 0x7fae7bccb875
    |          |          |
    |          |          |--11.11%-- 0xffffffffff60013b
    |          |          |
    |          |          |--11.11%-- __pthread_mutex_lock_internal
    |          |          |
    |          |          |--11.11%-- __errno_location

Fix this by removing the context markers when we process the
callchains to the tree.

Reported-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1269274173-20328-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-03-22 18:47:34 +01:00
Arnaldo Carvalho de Melo 6beba7adbe perf tools: Unify debug messages mechanisms
We were using eprintf in some places, that looks at a global
'verbose' level, and at other places passing a 'v' parameter to
specify the verbosity level, unify it by introducing
pr_{err,warning,debug,etc}, just like in the kernel.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1256153646-10097-1-git-send-email-acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-23 08:22:47 +02:00
Ingo Molnar 83a0944fa9 perf: Enable more compiler warnings
Related to a shadowed variable bug fix Valdis Kletnieks noticed
that perf does not get built with -Wshadow, which could have
helped us avoid the bug.

So enable -Wshadow and also enable the following warnings on
perf builds, in addition to the already enabled -Wall -Wextra
-std=gnu99 warnings:

 -Wcast-align
 -Wformat=2
 -Wshadow
 -Winit-self
 -Wpacked
 -Wredundant-decls
 -Wstack-protector
 -Wstrict-aliasing=3
 -Wswitch-default
 -Wswitch-enum
 -Wno-system-headers
 -Wundef
 -Wvolatile-register-var
 -Wwrite-strings
 -Wbad-function-cast
 -Wmissing-declarations
 -Wmissing-prototypes
 -Wnested-externs
 -Wold-style-definition
 -Wstrict-prototypes
 -Wdeclaration-after-statement

And change/fix the perf code to build cleanly under GCC 4.3.2.

The list of warnings enablement is rather arbitrary: it's based
on my (quick) reading of the GCC manpages and trying them on
perf.

I categorized the warnings based on individually enabling them
and looking whether they trigger something in the perf build.
If i liked those warnings (i.e. if they trigger for something
that arguably could be improved) i enabled the warning.

If the warnings seemed to come from language laywers spamming
the build with tons of nuisance warnings i generally kept them
off. Most of the sign conversion related warnings were in
this category. (A second patch enabling some of the sign
warnings might be welcome - sign bugs can be nasty.)

I also kept warnings that seem to make sense from their manpage
description and which produced no actual warnings on our code
base. These warnings might still be turned off if they end up
being a nuisance.

I also left out a few warnings that are not supported in older
compilers.

[ Note that these changes might break the build on older
  compilers i did not test, or on non-x86 architectures that
  produce different warnings, so more testing would be welcome. ]

Reported-by: Valdis.Kletnieks@vt.edu
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-16 10:47:47 +02:00
Frederic Weisbecker c0a8865e32 perf tools: callchain: Fix bad rounding of minimum rate
Sometimes we get callchain branches that have a rate under the
limit given by the user.

Say you launched:

 perf record -f -g -a ./hackbench 10
 perf report -g fractal,10.0

And you got:

2.33%       hackbench  [kernel]                  [k] _spin_lock_irqsave
                |
                |--78.57%-- remove_wait_queue
                |          poll_freewait
                |          do_sys_poll
                |          sys_poll
                |          sysenter_dispatch
                |          0xf7ffa430
                |          0x1ffadea3c
                |
                |--7.14%-- __up_read
                |          up_read
                |          do_page_fault
                |          page_fault
                |          0xf7ffa430
                |          0xa0df710000000a
                ...

It is abnormal to get a 7.14% branch whereas we passed a 10%
filter.

The problem is that we round down the minimum threshold. This
happens mostly when we have very low number of events. If the
total amount of your branch is 4 and you have a subranch of 3
events, filtering to 90% will be computed like follows:

  limit = 4 * 0.9;

The result is about 3.6, but the cast to integer will round
down to 3. It means that our filter is actually of 75%

We must then explicitly round up the minimum threshold.

Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: acme@redhat.com
Cc: peterz@infradead.org
Cc: efault@gmx.de
LKML-Reference: <20090809024235.GA10146@nowhere>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 13:07:46 +02:00
Frederic Weisbecker b0efe213f8 perf tools: callchain: Fix spurious 'perf report' warnings: ignore empty callchains
When the callchain tree comes to insert an empty backtrace, it
raises a spurious warning about the fact we are inserting an
empty. This is spurious because the radix tree assumes it did
something wrong to reach this state. But it didn't, we just met
an empty callchain that has to be ignored.

This happens occasionally with certain types of call-chain
recordings. If it happens it's a big nuisance as perf report
output starts with thousands of warning lines.

Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1249690585-9145-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:54:41 +02:00
Frederic Weisbecker 1953287bfe perf tools: Fix call-chain cumul hit based sub-total (fractal mode)
The callchain fractal mode builds each new total hits in a new
branch of profiling by using the parent's hits of the current
branch plus the hits of the children.

This is wrong, the total hits of a branch should be made of the
sum of every children hits, we must ignore the parent hits in
this scope.

This patch also fixes another mistake with the hit counting.

Now the rates are correct.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-09 12:54:33 +02:00
Frederic Weisbecker 805d127d62 perf report: Add "Fractal" mode output - support callchains with relative overhead rate
The current callchain displays the overhead rates as absolute:
relative to the total overhead.

This patch provides relative overhead percentage, in which each
branch of the callchain tree is a independant instrumentated object.

This provides a 'fractal' view of the call-chain profile: each
sub-graph looks like a profile in itself - relative to its parent.

You can produce such output by using the "fractal" mode
that you can abbreviate via f, fr, fra, frac, etc...

./perf report -s sym -c fractal

Example:

     8.46%  [k] copy_user_generic_string
                |
                |--52.01%-- generic_file_aio_read
                |          do_sync_read
                |          vfs_read
                |          |
                |          |--97.20%-- sys_pread64
                |          |          system_call_fastpath
                |          |          pread64
                |          |
                |           --2.81%-- sys_read
                |                     system_call_fastpath
                |                     __read
                |
                |--39.85%-- generic_file_buffered_write
                |          __generic_file_aio_write_nolock
                |          generic_file_aio_write
                |          do_sync_write
                |          reiserfs_file_write
                |          vfs_write
                |          |
                |          |--97.05%-- sys_pwrite64
                |          |          system_call_fastpath
                |          |          __pwrite64
                |          |
                |           --2.95%-- sys_write
                |                     system_call_fastpath
                |                     __write_nocancel
[...]

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246772361-9960-5-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-05 10:30:23 +02:00
Frederic Weisbecker e05b876c22 perf_counter tools: callchains: Manage the cumul hits on the fly
The cumul hits are the number of hits of every childs of a node
plus the hits of the current nodes, required for percentage
computing of a branch.

Theses numbers are calculated during the sorting of the branches of
the callchain tree using a depth first postfix traversal, so that
cumulative hits are propagated in the right order.

But if we plan to implement percentages relative to the parent and not
absolute percentages (relative to the whole overhead), we need to know
the cumulative hits of the parent before computing the children
because the relative minimum acceptable number of entries (ie: minimum
rate against the cumulative hits from the parent) is the basis to
filter the children against a given rate.

Then we need to handle the cumul hits on the fly to prepare the
implementation of relative overhead rates.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246772361-9960-4-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-05 10:30:22 +02:00
Frederic Weisbecker c20ab37ef3 perf_counter tools: Set the minimum percent for callchains to be displayed
Callchains output may become a burden on a trace because even
rarely hit site are exposed. This can be too much information.

Let the user set a threshold as a minimum percent of hits using
the new pattern for the -c option:

    -c mode,min_percent

Example:

$ perf report -s sym -c flat,4

     8.25%  [k] copy_user_generic_string
             4.19%
                copy_user_generic_string
                generic_file_aio_read
                do_sync_read
                vfs_read
                sys_pread64
                system_call_fastpath
                pread64

     5.39%  [k] search_by_key
     4.63%  0x00000000009e0a
     2.36%  [k] memcpy_c
[...]

$ perf report -s sym -c graph,2

     8.25%  [k] copy_user_generic_string
                |
                |--4.31%-- generic_file_aio_read
                |          do_sync_read
                |          vfs_read
                |          |
                |           --4.19%-- sys_pread64
                |                     system_call_fastpath
                |                     pread64
                |
                 --3.24%-- generic_file_buffered_write
                           __generic_file_aio_write_nolock
                           generic_file_aio_write
                           do_sync_write
                           reiserfs_file_write
                           vfs_write
                           |
                            --3.14%-- sys_pwrite64
                                      system_call_fastpath
                                      __pwrite64

     5.39%  [k] search_by_key
                |
                 --2.23%-- reiserfs_update_sd_size

     4.63%  0x00000000009e0a

     2.36%  [k] memcpy_c
[...]

You can also omit it and it will default to 0.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246558475-10624-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-02 21:38:37 +02:00
Frederic Weisbecker 4eb3e4788b perf report: Add support for callchain graph output
Currently, the printing of callchains is done in a single
vertical level, this is the "flat" mode:

8.25%  [k] copy_user_generic_string
             4.19%
                copy_user_generic_string
                generic_file_aio_read
                do_sync_read
                vfs_read
                sys_pread64
                system_call_fastpath
                pread64

This patch introduces a new "graph" mode which provides a
hierarchical output of factorized paths recursively sorted:

 8.25%  [k] copy_user_generic_string
                |
                |--4.31%-- generic_file_aio_read
                |          do_sync_read
                |          vfs_read
                |          |
                |          |--4.19%-- sys_pread64
                |          |          system_call_fastpath
                |          |          pread64
                |          |
                |           --0.12%-- sys_read
                |                     system_call_fastpath
                |                     __read
                |
                |--3.24%-- generic_file_buffered_write
                |          __generic_file_aio_write_nolock
                |          generic_file_aio_write
                |          do_sync_write
                |          reiserfs_file_write
                |          vfs_write
                |          |
                |          |--3.14%-- sys_pwrite64
                |          |          system_call_fastpath
                |          |          __pwrite64
                |          |
                |           --0.10%-- sys_write
[...]

The command line has then changed.

By providing the -c option, the callchain will output in the
flat mode by default.

But you can override it:

    perf report -c graph

or

    perf report -c flat

You can also pass the abreviated mode:

    perf report -c g

or

    perf report -c gra

will both make use of the graph mode.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246550301-8954-3-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-02 20:47:15 +02:00
Frederic Weisbecker 14f4654cbd perf_counter tools: Create new chain_for_each_child() iterator
Iterating through children of a node in the callchain tree
shows something that may be quite confusing at a first glance.
The head is the children field of the parent and the list nodes
are in the brothers field of the children.

This is because the childs are linked to the parent as a list
of "brothers" using the "children" list of the parent as a
head:

  ---------------
 | Parent (head) |-------------------------------------
  ---------------                                      |
     |                                                 |
  children                                             |
     |                                                 |
  -----------               -----------                |
 | 1st child |---brother---| 2nd child |---brother-----
  -----------               -----------

This makes the following strange pattern often occuring:

 list_for_each_entry(child, &parent->children, brothers) {
        // do something with children
 }

Abstract it to chain_for_each_child() to factorize and simplify
this pattern.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246550301-8954-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-02 20:47:14 +02:00
Ingo Molnar f37a291c52 perf_counter tools: Add more warnings and fix/annotate them
Enable -Wextra. This found a few real bugs plus a number
of signed/unsigned type mismatches/uncleanlinesses. It
also required a few annotations

All things considered it was still worth it so lets try with
this enabled for now.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-01 12:49:48 +02:00
Frederic Weisbecker deac911cbd perf_counter tools: Various fixes for callchains
The symbol resolving has of course revealed some bugs in the
callchain tree handling. This patch fixes some of them,
including:

- inherit the children from the parents while splitting a node
- fix list range moving
- fix indexes setting in callchains
- create a child on the current node if the path doesn't match in
  the existent children (was only done on the root)
- compare using symbols when possible so that we can match a function
  using any ip inside by referring to its start address.

The practical effects are:

- remove double callchains
- fix upside down or any random order of callchains
- fix wrong paths
- fix bad hits and percentage accounts

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246419315-9968-4-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-01 09:58:52 +02:00
Frederic Weisbecker 4424961ad6 perf_counter tools: Resolve symbols in callchains
This patch resolves the names, when possible, of each ip
present in the callchains while using the -c option with perf
report.

Example:

5.40%  [k] __d_lookup
             5.37%
                perf_callchain
                perf_counter_overflow
                intel_pmu_handle_irq
                perf_counter_nmi_handler
                notifier_call_chain
                atomic_notifier_call_chain
                notify_die
                do_nmi
                nmi
                do_lookup
                __link_path_walk
                path_walk
                do_path_lookup
                user_path_at
                sys_faccessat
                sys_access
                system_call_fastpath
                0x7fb609846f77

             0.01%
                perf_callchain
                perf_counter_overflow
                intel_pmu_handle_irq
                perf_counter_nmi_handler
                notifier_call_chain
                atomic_notifier_call_chain
                notify_die
                do_nmi
                nmi
                do_lookup
                __link_path_walk
                path_walk
                do_path_lookup
                user_path_at
                sys_faccessat

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246419315-9968-3-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-01 09:58:26 +02:00
Frederic Weisbecker 9198aa77b6 perf_counter tools: Fix storage size allocation of callchain list
Fix a confusion while giving the size of a callchain list
during its allocation. We are using the wrong structure size.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246419315-9968-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-01 09:58:23 +02:00
Frederic Weisbecker 8cb76d99d7 perf_counter tools: Prepare a small callchain framework
We plan to display the callchains depending on some user-configurable
parameters.

To gather the callchains stats from the recorded stream in a fast way,
this patch introduces an ad hoc radix tree adapted for callchains and also
a rbtree to sort these callchains once we have gathered every events
from the stream.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1246026481-8314-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-06-26 16:47:00 +02:00