linux-toradex.git/tools/perf/trace, branch v4.15-rc2

Merge branch 'linus' into perf/core, to fix conflicts

2017-11-07T09:30:18+00:00

Conflicts:
	tools/perf/arch/arm/annotate/instructions.c
	tools/perf/arch/arm64/annotate/instructions.c
	tools/perf/arch/powerpc/annotate/instructions.c
	tools/perf/arch/s390/annotate/instructions.c
	tools/perf/arch/x86/tests/intel-cqm.c
	tools/perf/ui/tui/progress.c
	tools/perf/util/zlib.c

Signed-off-by: Ingo Molnar

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55+00:00

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart 
Reviewed-by: Philippe Ombredanne 
Reviewed-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

perf trace beauty kcmp: Beautify arguments

2017-10-31T19:17:04+00:00

For some unknown reason there is no entry in tracefs's syscalls for
kcmp, i.e. no tracefs/events/syscalls/sys_{enter,exit}_kcmp, so we need
to provide a data dictionary for the fields.

To beautify the 'type' argument we automatically generate a strarray
from tools/include/uapi/kcmp.h, the idx1 and idx2 args, nowadays used
only if type == KCMP_FILE, are masked for all the other types and a
lookup is made for the thread and fd to show the path, if possible,
getting it from the probe:vfs_getname if in place or from procfs, races
allowing.

A system wide strace like tracing session, with callchains shows just
one user so far in this fedora 25 machine:

  # perf trace --max-stack 5 -e kcmp
  
  1502914.400 ( 0.001 ms): systemd/1 kcmp(pid1: 1 (systemd), pid2: 1 (systemd), type: FILE, idx1: 271, idx2: 25) = -1 ENOSYS Function not implemented
                                         syscall (/usr/lib64/libc-2.25.so)
                                         same_fd (/usr/lib/systemd/libsystemd-shared-233.so)
                                         service_add_fd_store (/usr/lib/systemd/systemd)
                                         service_notify_message.lto_priv.127 (/usr/lib/systemd/systemd)
  1502914.407 ( 0.001 ms): systemd/1 kcmp(pid1: 1 (systemd), pid2: 1 (systemd), type: FILE, idx1: 270, idx2: 25) = -1 ENOSYS Function not implemented
                                         syscall (/usr/lib64/libc-2.25.so)
                                         same_fd (/usr/lib/systemd/libsystemd-shared-233.so)
                                         service_add_fd_store (/usr/lib/systemd/systemd)
                                         service_notify_message.lto_priv.127 (/usr/lib/systemd/systemd)
  

The backtraces seem to agree this is really kcmp(), but this system
doesn't have the sys_kcmp(), bummer:

  # uname -a
  Linux jouet 4.14.0-rc3+ #1 SMP Fri Oct 13 12:21:12 -03 2017 x86_64 x86_64 x86_64 GNU/Linux
  # grep kcmp /proc/kallsyms
  ffffffffb60b8890 W sys_kcmp
  $ grep CONFIG_CHECKPOINT_RESTORE ../build/v4.14.0-rc3+/.config
  # CONFIG_CHECKPOINT_RESTORE is not set
  $

So systemd uses it, good fedora kernel config has it:

  $ grep CONFIG_CHECKPOINT_RESTORE /boot/config-4.13.4-200.fc26.x86_64
  CONFIG_CHECKPOINT_RESTORE=y
  [acme@jouet linux]$

/me goes to rebuild a kernel...

Cc: Adrian Hunter 
Cc: Andrey Vagin 
Cc: Cyrill Gorcunov 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-gz5fca968viw8m7hryjqvrln@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf trace beauty: Implement pid_fd beautifier

2017-10-31T19:17:03+00:00

One that given a pid and a fd, will try to get the path for that fd.
Will be used in the upcoming kcmp's KCMP_FILE beautifier.

Cc: Adrian Hunter 
Cc: Andrey Vagin 
Cc: Cyrill Gorcunov 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-7ketygp2dvs9h13wuakfncws@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf trace beauty prctl: Generate 'option' string table from kernel headers

2017-10-27T12:10:10+00:00

This is one more case where the way that syscall parameter values are
defined in kernel headers are easy to parse using a shell script that
will then generate the string table that gets used by the prctl 'option'
argument beautifier.

This way as soon as the header syncronization mechanism in perf's build
system detects a change in a copy of a kernel ABI header and that file
is syncronized, we get 'perf trace' updated automagically.

Further work needed for the PR_SET_ values, as well for using eBPF to
copy the non-integer arguments to/from the kernel.

E.g.: System wide prctl tracing:

  # perf trace -e prctl
  1668.028 ( 0.025 ms): TaskSchedulerR/10649 prctl(option: SET_NAME, arg2: 0x2b61d5db15d0) = 0
  3365.663 ( 0.018 ms): chrome/10650 prctl(option: SET_SECCOMP, arg2: 2, arg4: 8         ) = -1 EFAULT Bad address
  3366.585 ( 0.010 ms): chrome/10650 prctl(option: SET_NO_NEW_PRIVS, arg2: 1             ) = 0
  3367.173 ( 0.009 ms): TaskSchedulerR/10652 prctl(option: SET_NAME, arg2: 0x2b61d2aaa300) = 0
  3367.222 ( 0.003 ms): TaskSchedulerR/10653 prctl(option: SET_NAME, arg2: 0x2b61d2aaa1e0) = 0
  3367.244 ( 0.002 ms): TaskSchedulerR/10654 prctl(option: SET_NAME, arg2: 0x2b61d2aaa0c0) = 0
  3367.265 ( 0.002 ms): TaskSchedulerR/10655 prctl(option: SET_NAME, arg2: 0x2b61d2ac7f90) = 0
  3367.281 ( 0.002 ms): Chrome_ChildIO/10656 prctl(option: SET_NAME, arg2: 0x7efbe406bb11) = 0
  3367.220 ( 0.004 ms): TaskSchedulerS/10651 prctl(option: SET_NAME, arg2: 0x2b61d2ac1be0) = 0
  3370.906 ( 0.010 ms): GpuMemoryThrea/10657 prctl(option: SET_NAME, arg2: 0x7efbe386ab11) = 0
  3370.983 ( 0.003 ms): File/10658 prctl(option: SET_NAME, arg2: 0x7efbe3069b11          ) = 0
  3384.272 ( 0.020 ms): Compositor/10659 prctl(option: SET_NAME, arg2: 0x7efbe2868b11    ) = 0
  3612.091 ( 0.012 ms): DOM Worker/11489 prctl(option: SET_NAME, arg2: 0x7f49ab97ebf2    ) = 0

  4512.437 ( 0.004 ms): (sa1)/11490 prctl(option: SET_NAME, arg2: 0x7ffca15af844         ) = 0
  4512.468 ( 0.002 ms): (sa1)/11490 prctl(option: SET_MM, arg2: ARG_START, arg3: 0x7f5cb7c81000) = 0
  4512.472 ( 0.001 ms): (sa1)/11490 prctl(option: SET_MM, arg2: ARG_END, arg3: 0x7f5cb7c81006) = 0
  4514.667 ( 0.002 ms): (sa1)/11490 prctl(option: GET_SECUREBITS                         ) = 0

Cc: Adrian Hunter 
Cc: Andy Lutomirski 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-q0s2uw579o5ei6xlh2zjirgz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf trace beauty madvise: Generate 'behavior' string table from kernel headers

2017-09-21T16:12:59+00:00

This is one more case where the way that syscall parameter values are
defined in kernel headers are easy to parse using a shell script that
will then generate the string table that gets used by the madvise
'behaviour' argument beautifier.

This way as soon as the header syncronization mechanism in perf's build
system detects a change in a copy of a kernel ABI header and that file
is syncronized, we get 'perf trace' updated automagically.

So, when we syncronize this:

  Warning: Kernel ABI header at 'tools/include/uapi/asm-generic/mman-common.h' differs from latest version at 'include/uapi/asm-generic/mman-common.h'

We'll get these:

  #define MADV_WIPEONFORK 18              /* Zero memory on fork, child only */
  #define MADV_KEEPONFORK 19              /* Undo MADV_WIPEONFORK */

Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Rik van Riel 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-dolb0ghds4ui7wc1npgkchvc@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf trace beauty: Beautify pkey_{alloc,free,mprotect} arguments

2017-08-28T19:44:47+00:00

Reuse 'mprotect' beautifiers for 'pkey_mprotect'.

System wide tracing pkey_alloc, pkey_free and pkey_mprotect calls, with
backtraces:

  # perf trace -e pkey_alloc,pkey_mprotect,pkey_free --max-stack=5
     0.000 ( 0.011 ms): pkey/7818 pkey_alloc(init_val: DISABLE_ACCESS|DISABLE_WRITE) = -1 EINVAL Invalid argument
                                       syscall (/usr/lib64/libc-2.25.so)
                                       pkey_alloc (/home/acme/c/pkey)
     0.022 ( 0.003 ms): pkey/7818 pkey_mprotect(start: 0x7f28c3890000, len: 4096, prot: READ|WRITE, pkey: -1) = 0
                                       syscall (/usr/lib64/libc-2.25.so)
                                       pkey_mprotect (/home/acme/c/pkey)
     0.030 ( 0.002 ms): pkey/7818 pkey_free(pkey: -1                               ) = -1 EINVAL Invalid argument
                                       syscall (/usr/lib64/libc-2.25.so)
                                       pkey_free (/home/acme/c/pkey)

The tools/include/uapi/asm-generic/mman-common.h file is used to find
the access rights defines for the pkey_alloc syscall second argument.

Since we have the detector of changes for the tools/include header files
versus its kernel origin (include/uapi/asm-generic/mman-common.h), we'll
get whatever new flag appears for that argument automatically.

This method should be used in other cases where it is easy to generate
those flags tables because the header has properly namespaced defines
like PKEY_DISABLE_ACCESS and PKEY_DISABLE_WRITE.

Cc: Adrian Hunter 
Cc: Arnd Bergmann 
Cc: Dave Hansen 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-3xq5312qlks7wtfzv2sk3nct@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf trace beautify ioctl: Beautify perf ioctl's 'cmd' arg

2017-08-01T16:33:50+00:00

Also trying a new approach, using the copy of uapi/linux/perf_event.h we
auto generate the string tables, then include it in the ioctl cmd
beautifier.

This way either the perf developers will add the new commands to the
tools/ copy, like is happening with other areas of tools/include/ (bpf.h
comes to mind), or we'll be notified when building perf that our copy
drifted.

E.g., looking at some of the perf ioctls issued by the 'perf test' test cases:

  # (perf trace -e perf_event_open,ioctl perf test)  2>&1 | egrep "(cmd: PERF_|perf_event_open)"
  4: Read samples using the mmap interface      :
   348.811 ( 0.062 ms): perf/23351 perf_event_open(attr_uptr: 0x414a5e8, pid: 23351 (perf), group_fd: -1, flags: FD_CLOEXEC) = 3
   348.878 ( 0.039 ms): perf/23351 perf_event_open(attr_uptr: 0x414a5e8, pid: 23351 (perf), cpu: 1, group_fd: -1, flags: FD_CLOEXEC) = 4
   348.919 ( 0.036 ms): perf/23351 perf_event_open(attr_uptr: 0x414a5e8, pid: 23351 (perf), cpu: 2, group_fd: -1, flags: FD_CLOEXEC) = 5
   348.958 ( 0.036 ms): perf/23351 perf_event_open(attr_uptr: 0x414a5e8, pid: 23351 (perf), cpu: 3, group_fd: -1, flags: FD_CLOEXEC) = 6
   349.070 ( 0.046 ms): perf/23351 perf_event_open(attr_uptr: 0x414aa38, pid: 23351 (perf), group_fd: -1, flags: FD_CLOEXEC) = 7
   349.120 ( 0.037 ms): perf/23351 perf_event_open(attr_uptr: 0x414aa38, pid: 23351 (perf), cpu: 1, group_fd: -1, flags: FD_CLOEXEC) = 8
   349.161 ( 0.036 ms): perf/23351 perf_event_open(attr_uptr: 0x414aa38, pid: 23351 (perf), cpu: 2, group_fd: -1, flags: FD_CLOEXEC) = 9
   349.201 ( 0.035 ms): perf/23351 perf_event_open(attr_uptr: 0x414aa38, pid: 23351 (perf), cpu: 3, group_fd: -1, flags: FD_CLOEXEC) = 10
   349.306 ( 0.041 ms): perf/23351 perf_event_open(attr_uptr: 0x414b2d8, pid: 23351 (perf), group_fd: -1, flags: FD_CLOEXEC) = 11
   349.611 ( 0.005 ms): perf/23351 ioctl(fd: 3, cmd: PERF_ID, arg: 0x7fff025999b8) = 0
   349.619 ( 0.002 ms): perf/23351 ioctl(fd: 7, cmd: PERF_SET_OUTPUT, arg: 0x3  ) = 0
   349.623 ( 0.002 ms): perf/23351 ioctl(fd: 7, cmd: PERF_ID, arg: 0x7fff025999b8) = 0
   349.627 ( 0.002 ms): perf/23351 ioctl(fd: 11, cmd: PERF_SET_OUTPUT, arg: 0x3 ) = 0
   349.630 ( 0.001 ms): perf/23351 ioctl(fd: 11, cmd: PERF_ID, arg: 0x7fff025999b8) = 0

  7: PERF_RECORD_* events & perf_sample fields  :
   647.150 ( 0.014 ms): perf/23354 perf_event_open(attr_uptr: 0x7fff02599920, pid: -1, cpu: 2, group_fd: -1, flags: FD_CLOEXEC) = 3
   647.197 ( 0.076 ms): perf/23354 perf_event_open(attr_uptr: 0x414b478, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 3
   647.289 ( 0.040 ms): perf/23354 perf_event_open(attr_uptr: 0x414b478, pid: -1, group_fd: -1, flags: FD_CLOEXEC) = 3
   647.368 ( 0.011 ms): perf/23354 perf_event_open(attr_uptr: 0x414a5e8, pid: 23355 (perf), group_fd: -1, flags: FD_CLOEXEC) = 3
   647.381 ( 0.005 ms): perf/23354 perf_event_open(attr_uptr: 0x414a5e8, pid: 23355 (perf), cpu: 1, group_fd: -1, flags: FD_CLOEXEC) = 4
   647.387 ( 0.005 ms): perf/23354 perf_event_open(attr_uptr: 0x414a5e8, pid: 23355 (perf), cpu: 2, group_fd: -1, flags: FD_CLOEXEC) = 5
   647.393 ( 0.004 ms): perf/23354 perf_event_open(attr_uptr: 0x414a5e8, pid: 23355 (perf), cpu: 3, group_fd: -1, flags: FD_CLOEXEC) = 7
   648.026 ( 0.011 ms): perf/23354 ioctl(fd: 3, cmd: PERF_ENABLE) = 0
   648.038 ( 0.002 ms): perf/23354 ioctl(fd: 4, cmd: PERF_ENABLE) = 0
   648.042 ( 0.002 ms): perf/23354 ioctl(fd: 5, cmd: PERF_ENABLE) = 0
   648.045 ( 0.002 ms): perf/23354 ioctl(fd: 7, cmd: PERF_ENABLE) = 0

  18: Breakpoint overflow signal handler         :
  2772.721 ( 0.017 ms): perf/23375 perf_event_open(attr_uptr: 0x7fff02599d20, pid: -1, cpu: 3, group_fd: -1, flags: FD_CLOEXEC) = 3
  2772.748 ( 0.009 ms): perf/23375 perf_event_open(attr_uptr: 0x7fff02599e60, cpu: -1, group_fd: -1, flags: FD_CLOEXEC) = 3
  2772.768 ( 0.002 ms): perf/23375 ioctl(fd: 3, cmd: PERF_RESET) = 0
  2772.776 ( 0.008 ms): perf/23375 perf_event_open(attr_uptr: 0x7fff02599e60, cpu: -1, group_fd: -1, flags: FD_CLOEXEC) = 4
  2772.788 ( 0.002 ms): perf/23375 ioctl(fd: 4, cmd: PERF_RESET) = 0
  2772.791 ( 0.006 ms): perf/23375 perf_event_open(attr_uptr: 0x7fff02599e60, cpu: -1, group_fd: -1, flags: FD_CLOEXEC) = 5
  2772.800 ( 0.001 ms): perf/23375 ioctl(fd: 5, cmd: PERF_RESET) = 0
  2772.803 ( 0.005 ms): perf/23375 ioctl(fd: 3, cmd: PERF_ENABLE) = 0
  2772.810 ( 0.004 ms): perf/23375 ioctl(fd: 4, cmd: PERF_ENABLE) = 0
  2772.815 ( 0.004 ms): perf/23375 ioctl(fd: 5, cmd: PERF_ENABLE) = 0


Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-ahotwscqt080ae0ulu3zznh2@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf trace beautify ioctl: Beautify vhost virtio ioctl's 'cmd' arg

2017-08-01T16:32:46+00:00

Also trying a new approach, using a copy of uapi/linux/vhost.h we auto
generate the string tables, then include it in the ioctl cmd beautifier.

This way either the KVM developers will add the new commands to the
tools/ copy, like is happening with other areas of tools/include/ (bpf.h
comes to mind), or we'll be notified when building perf that our copy
drifted.

E.g., doing syswide tracing grepping for the newly beautified VHOST
ioctls:

  # perf trace -e ioctl 2>&1 | grep VHOST
  3873.064 ( 0.099 ms): qemu-system-x8/21238 ioctl(fd: 27, cmd: VHOST_NET_SET_BACKEND, arg: 0x7fff053dffe0) = 0
  3873.168 ( 0.019 ms): qemu-system-x8/21238 ioctl(fd: 27, cmd: VHOST_NET_SET_BACKEND, arg: 0x7fff053dffe0) = 0
  3873.226 ( 0.006 ms): qemu-system-x8/21238 ioctl(fd: 27, cmd: VHOST_GET_VRING_BASE, arg: 0x7fff053dff60) = 0
  3873.244 ( 0.002 ms): qemu-system-x8/21238 ioctl(fd: 27, cmd: VHOST_GET_VRING_BASE, arg: 0x7fff053dff60) = 0
  3873.817 ( 0.014 ms): qemu-system-x8/21238 ioctl(fd: 27, cmd: VHOST_SET_VRING_CALL, arg: 0x7fff053dff20) = 0
  3873.838 ( 0.004 ms): qemu-system-x8/21238 ioctl(fd: 27, cmd: VHOST_SET_VRING_CALL, arg: 0x7fff053dff20) = 0
  4701.372 ( 0.006 ms): qemu-system-x8/21238 ioctl(fd: 27, cmd: VHOST_SET_VRING_CALL, arg: 0x7fff053dfe20) = 0
  4701.417 ( 0.007 ms): qemu-system-x8/21238 ioctl(fd: 27, cmd: VHOST_SET_VRING_CALL, arg: 0x7fff053dfe20) = 0
  4701.563 ( 0.004 ms): qemu-system-x8/21238 ioctl(fd: 27, cmd: VHOST_SET_FEATURES, arg: 0x7fff053dfe88) = 0
  4701.571 ( 0.028 ms): qemu-system-x8/21238 ioctl(fd: 27, cmd: VHOST_SET_MEM_TABLE, arg: 0x563c7c906870) = 0
  4701.604 ( 0.003 ms): qemu-system-x8/21238 ioctl(fd: 27, cmd: VHOST_SET_VRING_NUM, arg: 0x7fff053dff00) = 0
  4701.609 ( 0.002 ms): qemu-system-x8/21238 ioctl(fd: 27, cmd: VHOST_SET_VRING_BASE, arg: 0x7fff053dff00) = 0
  4701.615 ( 0.002 ms): qemu-system-x8/21238 ioctl(fd: 27, cmd: VHOST_SET_VRING_ADDR, arg: 0x7fff053dfe70) = 0
  4701.619 ( 0.008 ms): qemu-system-x8/21238 ioctl(fd: 27, cmd: VHOST_SET_VRING_KICK, arg: 0x7fff053dfef0) = 0
  4701.634 ( 0.004 ms): qemu-system-x8/21238 ioctl(fd: 27, cmd: VHOST_SET_VRING_NUM, arg: 0x7fff053dff00) = 0
  4701.640 ( 0.002 ms): qemu-system-x8/21238 ioctl(fd: 27, cmd: VHOST_SET_VRING_BASE, arg: 0x7fff053dff00) = 0
  4701.644 ( 0.002 ms): qemu-system-x8/21238 ioctl(fd: 27, cmd: VHOST_SET_VRING_ADDR, arg: 0x7fff053dfe70) = 0
  4701.648 ( 0.009 ms): qemu-system-x8/21238 ioctl(fd: 27, cmd: VHOST_SET_VRING_KICK, arg: 0x7fff053dfef0) = 0
  4701.665 ( 0.005 ms): qemu-system-x8/21238 ioctl(fd: 27, cmd: VHOST_NET_SET_BACKEND, arg: 0x7fff053dff80) = 0
  4701.672 ( 0.004 ms): qemu-system-x8/21238 ioctl(fd: 27, cmd: VHOST_NET_SET_BACKEND, arg: 0x7fff053dff80) = 0
^C

 '-e ioctl' uses tracepoint filters, in time this will be replaces by
eBPF filters hooked at the syscall tracepoints and that "grep VHOST"
will also be done with eBPF, right at the kernel, to reduce overhead.

Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Jason Wang 
Cc: Jiri Olsa 
Cc: "Michael S. Tsirkin" 
Cc: Namhyung Kim 
Cc: Paolo Bonzini 
Cc: Radim Krčmář 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-2gthnhpliunvakywjterrzz3@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf trace beauty ioctl: Pass _IOC_DIR to the per _IOC_TYPE scnprintf

2017-08-01T16:04:52+00:00

Not all subsystems use the fact that we may have the same _IOC_NR for
different _IOC_DIR, as in the end it'll result in a different ioctl
number.

So, for instance, vhost virtio has:

  #define VHOST_GET_FEATURES      _IOR(VHOST_VIRTIO, 0x00, __u64)
  #define VHOST_SET_FEATURES      _IOW(VHOST_VIRTIO, 0x00, __u64)

So same _IOC_NR (0x00) but different _IOC_DIR (R versus W), but it also
have:

  #define VHOST_SET_VRING_ENDIAN _IOW(VHOST_VIRTIO, 0x13, struct vhost_vring_state)
  #define VHOST_GET_VRING_ENDIAN _IOW(VHOST_VIRTIO, 0x14, struct vhost_vring_state)

A "get" operation that uses a "W" _IOC_DIR, and its implementation, uses
copy_to_user, it should've probably been _IOR().

Then:

  /* Base value where queue looks for available descriptors */
  #define VHOST_SET_VRING_BASE _IOW(VHOST_VIRTIO, 0x12, struct vhost_vring_state)
  /* Get accessor: reads index, writes value in num */
  #define VHOST_GET_VRING_BASE _IOWR(VHOST_VIRTIO, 0x12, struct vhost_vring_state)

So we'll need to use _IOC_DIR() to disambiguate the VHOST_VIRTIO ioctl
bautifier.

Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Paolo Bonzini 
Cc: Radim Krčmář 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-rq6q717ql7j2z7kuccafgq84@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo