linux.git/tools/perf/util, branch v5.0-rc2

perf symbols: Add 'arch_cpu_idle' to the list of kernel idle symbols

2019-01-09T19:21:15+00:00

When testing 'perf top' on a armhf system (32-bit, Orange Pi Zero), I
noticed that 'arch_cpu_idle' dominated, add it to the list of idle
symbols, so that we can see what is that being done when not idle.

Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: https://lkml.kernel.org/n/tip-4q2b5g4p2hrstrhp9t2mrlho@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Make find_vdso_map() more modular

2019-01-08T16:28:13+00:00

In preparation for checking that the vectors page on the ARM
architecture, refactor the find_vdso_map() function to accept finding an
arbitrary string and create a dedicated helper function for that under
util/find-map.c and update the filename to find-map.c and all references
to it: perf-read-vdso.c and util/vdso.c.

Signed-off-by: Florian Fainelli 
Acked-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Chris Healy 
Cc: Greg Kroah-Hartman 
Cc: Kim Phillips 
Cc: Lucas Stach 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Russell King 
Cc: Thomas Gleixner 
Cc: Thomas Richter 
Link: http://lkml.kernel.org/r/20181221034337.26663-2-f.fainelli@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo

Merge tag 'perf-core-for-mingo-4.21-20190104' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent

2019-01-08T15:31:19+00:00

Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:

perf annotate:

  Ivan Krylov:

  - Pass filename to objdump via execl, fixing usage with filenames
    with special characters.

perf report:

  Jin Yao:

     Fix wrong iteration count in --branch-history

perf stat:

  Jin Yao:

  - Fix endless wait for child process

perf test:

  Arnaldo Carvalho de Melo:

  - Use a fallback to get the pathname in vfs_getname in

tools build:

  Jiri Olsa:

  - Allow overriding CFLAGS assignments.

Misc:

  Arnaldo Carvalho de Melo:

  - Syncronize UAPI headers

  Mattias Jacobsson:

  - Remove redundant va_end() in strbuf_addv()

Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Ingo Molnar

Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2019-01-07T00:30:14+00:00

Pull perf tooling updates form Ingo Molnar:
 "A final batch of perf tooling changes: mostly fixes and small
  improvements"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (29 commits)
  perf session: Add comment for perf_session__register_idle_thread()
  perf thread-stack: Fix thread stack processing for the idle task
  perf thread-stack: Allocate an array of thread stacks
  perf thread-stack: Factor out thread_stack__init()
  perf thread-stack: Allow for a thread stack array
  perf thread-stack: Avoid direct reference to the thread's stack
  perf thread-stack: Tidy thread_stack__bottom() usage
  perf thread-stack: Simplify some code in thread_stack__process()
  tools gpio: Allow overriding CFLAGS
  tools power turbostat: Override CFLAGS assignments and add LDFLAGS to build command
  tools thermal tmon: Allow overriding CFLAGS assignments
  tools power x86_energy_perf_policy: Override CFLAGS assignments and add LDFLAGS to build command
  perf c2c: Increase the HITM ratio limit for displayed cachelines
  perf c2c: Change the default coalesce setup
  perf trace beauty ioctl: Beautify USBDEVFS_ commands
  perf trace beauty: Export function to get the files for a thread
  perf trace: Wire up ioctl's USBDEBFS_ cmd table generator
  perf beauty ioctl: Add generator for USBDEVFS_ ioctl commands
  tools headers uapi: Grab a copy of usbdevice_fs.h
  perf trace: Store the major number for a file when storing its pathname
  ...

perf strbuf: Remove redundant va_end() in strbuf_addv()

2019-01-04T15:54:49+00:00

Each call to va_copy() should have one, and only one, corresponding call
to va_end(). In strbuf_addv() some code paths result in va_end() getting
called multiple times. Remove the superfluous va_end().

Signed-off-by: Mattias Jacobsson <2pi@mok.nu>
Cc: Jiri Olsa 
Cc: Peter Zijlstra 
Cc: Sanskriti Sharma 
Link: http://lkml.kernel.org/r/20181229141750.16945-1-2pi@mok.nu
Fixes: ce49d8436cff ("perf strbuf: Match va_{add,copy} with va_end")
Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Pass filename to objdump via execl

2019-01-04T15:54:49+00:00

The symbol__disassemble() function uses shell to launch objdump and
filter its output via grep. Passing filenames by interpolating them into
the command line via "%s" may lead to problems if said filenames contain
special characters.

Instead, pass the filename as a command line argument where it is not
subject to any kind of interpretation, then use quoted shell
interpolation to build the strings we need safely.

Signed-off-by: Ivan Krylov 
Acked-by: Jiri Olsa 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexander Shishkin 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/20181014111803.5d83b806@Tarkus
Signed-off-by: Arnaldo Carvalho de Melo

perf report: Fix wrong iteration count in --branch-history

2019-01-04T15:54:49+00:00

By calculating the removed loops, we can get the iteration count.

But the iteration count could be reported incorrectly, reporting
impossibly high counts.

That's because previous code uses the number of removed LBR entries for
the iteration count. That's not good. Fix this by increasing the
iteration count when a loop is detected.

When matching the chain, the iteration count would be added up, finally we need
to compute the average value when printing out.

For example,

  $ perf report --branch-history --stdio --no-children

Before:

  ---f2 +0
     |
     |--33.62%--f1 +9 (cycles:1)
     |          f1 +0
     |          main +22 (cycles:1)
     |          main +17
     |          main +38 (cycles:1)
     |          main +27
     |          f1 +26 (cycles:1)
     |          f1 +24
     |          f2 +27 (cycles:7)
     |          f2 +0
     |          f1 +19 (cycles:1)
     |          f1 +14
     |          f2 +27 (cycles:11)
     |          f2 +0
     |          f1 +9 (cycles:1 iter:2968 avg_cycles:3)
     |          f1 +0
     |          main +22 (cycles:1 iter:2968 avg_cycles:3)
     |          main +17
     |          main +38 (cycles:1 iter:2968 avg_cycles:3)

2968 is an impossible high iteration count and avg_cycles is too small.

After:

  ---f2 +0
     |
     |--33.62%--f1 +9 (cycles:1)
     |          f1 +0
     |          main +22 (cycles:1)
     |          main +17
     |          main +38 (cycles:1)
     |          main +27
     |          f1 +26 (cycles:1)
     |          f1 +24
     |          f2 +27 (cycles:7)
     |          f2 +0
     |          f1 +19 (cycles:1)
     |          f1 +14
     |          f2 +27 (cycles:11)
     |          f2 +0
     |          f1 +9 (cycles:1 iter:1 avg_cycles:23)
     |          f1 +0
     |          main +22 (cycles:1 iter:1 avg_cycles:23)
     |          main +17
     |          main +38 (cycles:1 iter:1 avg_cycles:23)

avg_cycles:23 is the average cycles of this iteration.

Fixes: c4ee06251d42 ("perf report: Calculate the average cycles of iterations")

Signed-off-by: Jin Yao 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1546582230-17507-1-git-send-email-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo

Remove 'type' argument from access_ok() function

2019-01-04T02:57:57+00:00

Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.

It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access.  But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.

A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model.  And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.

This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.

There were a couple of notable cases:

 - csky still had the old "verify_area()" name as an alias.

 - the iter_iov code had magical hardcoded knowledge of the actual
   values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
   really used it)

 - microblaze used the type argument for a debug printout

but other than those oddities this should be a total no-op patch.

I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something.  Any missed conversion should be trivially fixable, though.

Signed-off-by: Linus Torvalds

perf session: Add comment for perf_session__register_idle_thread()

2019-01-02T14:05:06+00:00

Add a comment to perf_session__register_idle_thread() to bring attention to
a pitfall with the idle task thread structure. The pitfall is that there
should really be a 'struct thread' for the idle task of each cpu, but there
is only one that can have pid == tid == 0.

Signed-off-by: Adrian Hunter 
Acked-by: Jiri Olsa 
Link: http://lkml.kernel.org/r/20181221120620.9659-9-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf thread-stack: Fix thread stack processing for the idle task

2019-01-02T14:03:17+00:00

perf creates a single 'struct thread' to represent the idle task. That
is because threads are identified by PID and TID, and the idle task
always has PID == TID == 0.

However, there are actually separate idle tasks for each CPU. That
creates a problem for thread stack processing which assumes that each
thread has a single stack, not one stack per CPU.

Fix that by passing through the CPU number, and in the case of the idle
"thread", pick the thread stack from an array based on the CPU number.

Signed-off-by: Adrian Hunter 
Acked-by: Jiri Olsa 
Link: http://lkml.kernel.org/r/20181221120620.9659-8-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo