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

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

New user selectable features:

  - Support recording running/enabled time in 'perf record' (Andi Kleen)

  - New tool: 'perf data' for converting perf.data to other formats,
    initially for the CTF (Common Trace Format) from LTTng (Jiri Olsa, Sebastian Siewior)

User visible changes:

  - Only insert blank duration bracket when tracing syscalls in 'perf trace' (Arnaldo Carvalho de Melo)

  - Filter out the trace pid when no threads are specified in 'perf trace' (Arnaldo Carvalho de Melo)

  - Add 'perf trace' man page entry for --event (Arnaldo Carvalho de Melo)

  - Dump stack on segfaults in 'perf trace' (Arnaldo Carvalho de Melo)

Infrastructure changes:

  - Introduce set_filter_pid and set_filter_pids methods in the evlist class (Arnaldo Carvalho de Melo)

  - Some perf_session untanglement patches, removing the need to pass a
    perf_session instance for things that are related to evlists, so that
    tools that don't deal with perf.data files like trace in live mode can
    make use of the ordered_events class (Arnaldo Carvalho de Melo)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Signed-off-by: Ingo Molnar <mingo@kernel.org>

Some of the tracers bring their own id or pid fields and we can end up
having two of them. This patch adds a "perf_" prefix to the 'generic'
fields so we avoid a clash of the member names.

The change is visible in the babeltrace output:

Before:
  $ babeltrace ./ctf-data/
  [03:19:13.962131936] (+0.000001935) cycles: { }, { ip = 0xFFFFFFFF8105443A, tid = 20714, pid = 20714, period = 8 }
  [03:19:13.962133732] (+0.000001796) cycles: { }, { ip = 0xFFFFFFFF8105443A, tid = 20714, pid = 20714, period = 114 }
  ...

Now:
  $ babeltrace ./ctf-data/
  [03:19:13.962131936] (+0.000001935) cycles: { }, { perf_ip = 0xFFFFFFFF8105443A, perf_tid = 20714, perf_pid = 20714, perf_period = 8 }
  [03:19:13.962133732] (+0.000001796) cycles: { }, { perf_ip = 0xFFFFFFFF8105443A, perf_tid = 20714, perf_pid = 20714, perf_period = 114 }
  ...
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: David Ahern <dsahern@gmail.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jeremie Galarneau <jgalar@efficios.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1424470628-5969-5-git-send-email-jolsa@kernel.orgSigned-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Adding 'perf data convert' to convert perf data file into different
format. This patch adds support for CTF format conversion.

To convert perf.data into CTF run:
  $ perf data convert --to-ctf=./ctf-data/
  [ perf data convert: Converted 'perf.data' into CTF data './ctf-data/' ]
  [ perf data convert: Converted and wrote 11.268 MB (100230 samples) ]

The command will create CTF metadata out of perf.data file (or one
specified via -i option) and then convert all sample events into single
CTF stream.

Each sample_type bit is translated into separated CTF event field apart
from following exceptions:

  PERF_SAMPLE_RAW          - added in next patch
  PERF_SAMPLE_READ         - TODO
  PERF_SAMPLE_CALLCHAIN    - TODO
  PERF_SAMPLE_BRANCH_STACK - TODO
  PERF_SAMPLE_REGS_USER    - TODO
  PERF_SAMPLE_STACK_USER   - TODO

  $ perf --debug=data-convert=2 data convert ...

The converted CTF data could be analyzed by CTF tools, like babletrace
or tracecompass [1].

  $ babeltrace ./ctf-data/
  [03:19:13.962125533] (+?.?????????) cycles: { }, { ip = 0xFFFFFFFF8105443A, tid = 20714, pid = 20714, period = 1 }
  [03:19:13.962130001] (+0.000004468) cycles: { }, { ip = 0xFFFFFFFF8105443A, tid = 20714, pid = 20714, period = 1 }
  [03:19:13.962131936] (+0.000001935) cycles: { }, { ip = 0xFFFFFFFF8105443A, tid = 20714, pid = 20714, period = 8 }
  [03:19:13.962133732] (+0.000001796) cycles: { }, { ip = 0xFFFFFFFF8105443A, tid = 20714, pid = 20714, period = 114 }
  [03:19:13.962135557] (+0.000001825) cycles: { }, { ip = 0xFFFFFFFF8105443A, tid = 20714, pid = 20714, period = 2087 }
  [03:19:13.962137627] (+0.000002070) cycles: { }, { ip = 0xFFFFFFFF81361938, tid = 20714, pid = 20714, period = 37582 }
  [03:19:13.962161091] (+0.000023464) cycles: { }, { ip = 0xFFFFFFFF8124218F, tid = 20714, pid = 20714, period = 600246 }
  [03:19:13.962517569] (+0.000356478) cycles: { }, { ip = 0xFFFFFFFF811A75DB, tid = 20714, pid = 20714, period = 1325731 }
  [03:19:13.969518008] (+0.007000439) cycles: { }, { ip = 0x34080917B2, tid = 20714, pid = 20714, period = 1144298 }

The following members to the ctf-environment were decided to be added to
distinguish and specify perf CTF data:

  - domain

    It says "kernel" because it contains a kernel trace (not to be
    confused with a user space like lttng-ust does)

  - tracer_name

    It says perf. This can be used to distinguish between lttng and perf
    CTF based trace.

  - version

    The kernel version from stream. In addition to release, this is what
    it looks like on a Debian kernel:

      release = "3.14-1-amd64";
      version = "3.14.0";

[1] http://projects.eclipse.org/projects/tools.tracecompassSigned-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: David Ahern <dsahern@gmail.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jeremie Galarneau <jgalar@efficios.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1424470628-5969-4-git-send-email-jolsa@kernel.orgSigned-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Adding new 'perf data' command to provide operations over data files.

The 'perf data convert' sub command is coming in following patch, but
there's possibility for other useful commands like 'perf data ls' (to
display perf data file in directory in ls style).
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jeremie Galarneau <jgalar@efficios.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1424470628-5969-3-git-send-email-jolsa@kernel.orgSigned-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Adding feature check for babeltrace library [1], which will be used for
perf data file CTF [2] conversion in following patches.

The babeltrace library is now automatically detected as standard
feature. It's possible to specify LIBBABELTRACE_DIR make variable to
specify location of installed libbabeltrace, like:

  $ make LIBBABELTRACE_DIR=/opt/libbabeltrace/
    BUILD:   Doing 'make -j4' parallel build

  Auto-detecting system features:
  ...                         dwarf: [ on  ]
  ...                         glibc: [ on  ]
  ...                          gtk2: [ on  ]
  ...                      libaudit: [ on  ]
  ...                        libbfd: [ on  ]
  ...                        libelf: [ on  ]
  ...                       libnuma: [ on  ]
  ...                       libperl: [ on  ]
  ...                     libpython: [ on  ]
  ...                      libslang: [ on  ]
  ...                     libunwind: [ on  ]
  ...                 libbabeltrace: [ on  ]
  ...            libdw-dwarf-unwind: [ on  ]
  ...                          zlib: [ on  ]
  ...     DWARF post unwind library: libunwind

NOTE The installation of the [1] to to used by above make:
     $ git clone git://git.efficios.com/babeltrace.git
     $ cd babeltrace
     $ vim README
     $ ./bootstrap
     $ ./configure --prefix=/opt/libbabeltrace
     $ make prefix=/opt/libbabeltrace
     $ sudo make install prefix=/opt/libbabeltrace

Please make sure that the /opt/libbabeltrace/lib directory is in your
LD_LIBRARY_PATH:

 $ export LD_LIBRARY_PATH=/opt/libbabeltrace/lib

[1] babeltrace - http://www.efficios.com/babeltrace
[2] Common Trace Format - http://www.efficios.com/ctfSigned-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jeremie Galarneau <jgalar@efficios.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1424470628-5969-2-git-send-email-jolsa@kernel.orgSigned-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
[ Added missing babeltrace build instructions ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Add an option to perf record to record running/enabled time for read
events, similar to what stat does.

This is useful to understand multiplexing problems.

Right now the report support is not great, but at least report -D
already supports it.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1424819620-16043-1-git-send-email-andi@firstfloor.org
[ Fixed the Documentation entry to match the OPT_BOOLEAN one ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-fmto8ft6jrtwz09dxn5d4z8w@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

  [root@ssdandy ~]# perf trace --filter-pids 16348
     0.000 ( 0.000 ms): tuned/1027  ... [continued]: select()) = 0 Timeout
   793.770 ( 0.000 ms): lsmd/895  ... [continued]: select()) = 0 Timeout
   793.775 (793.724 ms): tuned/1027 select(tvp: 0x7f7655556e50) ...
  perf: Segmentation fault
  Obtained 15 stack frames.
  perf(dump_stack+0x2e) [0x4ed330]
  perf(sighandler_dump_stack+0x2e) [0x4ed40f]
  /lib64/libc.so.6(+0x35640) [0x7fa2d5b69640]
  perf() [0x4c2d35]
  perf(machine__findnew_thread+0x39) [0x4c2ed6]
  perf() [0x454a4d]
  perf() [0x455f87]
  perf() [0x456556]
  perf(cmd_trace+0xa7e) [0x4580af]
  perf() [0x4867bd]
  perf() [0x486a1c]
  perf() [0x486b68]
  perf(main+0x23b) [0x486ec9]
  /lib64/libc.so.6(__libc_start_main+0xf5) [0x7fa2d5b55af5]
  perf() [0x41bd91]
[  root@ssdandy ~]#

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-v38cbxcnm2yf5qn9u4y4n9ab@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

To use in stdio based tools, like 'trace'.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-79kjmerlw6d88csyx1afzwvn@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

To figure out if ordered_events are being used when doing a flush
operation, it is enough to check if there were in fact some events
queued, i.e. look at oe->nr_events.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-1c5r404vy766kt5nflv88uag@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

.. after extensive statistical analysis of my G+ polling, I've come to
the inescapable conclusion that internet polls are bad.

Big surprise.

But "Hurr durr I'ma sheep" trounced "I like online polls" by a 62-to-38%
margin, in a poll that people weren't even supposed to participate in.
Who can argue with solid numbers like that? 5,796 votes from people who
can't even follow the most basic directions?

In contrast, "v4.0" beat out "v3.20" by a slimmer margin of 56-to-44%,
but with a total of 29,110 votes right now.

Now, arguably, that vote spread is only about 3,200 votes, which is less
than the almost six thousand votes that the "please ignore" poll got, so
it could be considered noise.

But hey, I asked, so I'll honor the votes.

Pull ext4 fixes from Ted Ts'o:
 "Ext4 bug fixes.

  We also reserved code points for encryption and read-only images (for
  which the implementation is mostly just the reserved code point for a
  read-only feature :-)"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: fix indirect punch hole corruption
  ext4: ignore journal checksum on remount; don't fail
  ext4: remove duplicate remount check for JOURNAL_CHECKSUM change
  ext4: fix mmap data corruption in nodelalloc mode when blocksize < pagesize
  ext4: support read-only images
  ext4: change to use setup_timer() instead of init_timer()
  ext4: reserve codepoints used by the ext4 encryption feature
  jbd2: complain about descriptor block checksum errors

Pull more vfs updates from Al Viro:
 "Assorted stuff from this cycle.  The big ones here are multilayer
  overlayfs from Miklos and beginning of sorting ->d_inode accesses out
  from David"

* 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (51 commits)
  autofs4 copy_dev_ioctl(): keep the value of ->size we'd used for allocation
  procfs: fix race between symlink removals and traversals
  debugfs: leave freeing a symlink body until inode eviction
  Documentation/filesystems/Locking: ->get_sb() is long gone
  trylock_super(): replacement for grab_super_passive()
  fanotify: Fix up scripted S_ISDIR/S_ISREG/S_ISLNK conversions
  Cachefiles: Fix up scripted S_ISDIR/S_ISREG/S_ISLNK conversions
  VFS: (Scripted) Convert S_ISLNK/DIR/REG(dentry->d_inode) to d_is_*(dentry)
  SELinux: Use d_is_positive() rather than testing dentry->d_inode
  Smack: Use d_is_positive() rather than testing dentry->d_inode
  TOMOYO: Use d_is_dir() rather than d_inode and S_ISDIR()
  Apparmor: Use d_is_positive/negative() rather than testing dentry->d_inode
  Apparmor: mediated_filesystem() should use dentry->d_sb not inode->i_sb
  VFS: Split DCACHE_FILE_TYPE into regular and special types
  VFS: Add a fallthrough flag for marking virtual dentries
  VFS: Add a whiteout dentry type
  VFS: Introduce inode-getting helpers for layered/unioned fs environments
  Infiniband: Fix potential NULL d_inode dereference
  posix_acl: fix reference leaks in posix_acl_create
  autofs4: Wrong format for printing dentry
  ...

All it wants is session->evlist.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-6w9663gka3jb1j1rfxxd5jcq@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Further untangling perf_session from plain event delivery routines.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-cvz8e6pwyogs4w14582iis9w@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-pxxm1liohog3d6i826x8sud8@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

For tools that don't deal with perf.data files, thus do not need to
use perf_session.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-kglq67gvauq9tak02a4se00r@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Start to untangle session from delivering samples, as there are
tools that want to use ordered_events and don't use perf_session at all.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-rn4pk3pjxd78sgzrkn19tktp@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Because we need to use ordered_events in some cases, so we will need to
first have them in a queue, order that queue, and then process the
event.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-cmkw9zgoh0z4r218957ftp1a@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Forgot to do it when adding the feature.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-mx152b6x9cgknhw91vsyjlnd@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

When tracing in X we get event loops due to the tracing activity, i.e.
updates to a gnome-terminal that generate syscalls for X.org, etc.

To get a more useful view of what is happening, syscall wise, system
wide, we need to filter those, like in:

 # ps ax|egrep '981|2296|1519' | grep -v egrep
   981 tty1 Ss+ 5:40 /usr/bin/Xorg :0 -background none ...
  1519 ?    Sl  2:22 /usr/bin/gnome-shell
  2296 ?    Sl  4:16 /usr/libexec/gnome-terminal-server
 #

 # trace -e write --filter-pids 981,2296,1519
    0.385 ( 0.021 ms): goa-daemon/2061 write(fd: 1</dev/null>, buf: 0x7fbeb017b000, count: 136) = 136
    0.922 ( 0.014 ms): goa-daemon/2061 write(fd: 1</dev/null>, buf: 0x7fbeb017b000, count: 140) = 140
 5006.525 ( 0.029 ms): goa-daemon/2061 write(fd: 1</dev/null>, buf: 0x7fbeb017b000, count: 136) = 136
 5007.235 ( 0.023 ms): goa-daemon/2061 write(fd: 1</dev/null>, buf: 0x7fbeb017b000, count: 140) = 140
 5177.646 ( 0.018 ms): rtkit-daemon/782 write(fd: 5<anon_inode:[eventfd]>, buf: 0x7f7eea70be88, count: 8) = 8
 8314.497 ( 0.004 ms): gsd-locate-poi/2084 write(fd: 5<anon_inode:[eventfd]>, buf: 0x7fffe96af7b0, count: 8) = 8
 8314.518 ( 0.002 ms): gsd-locate-poi/2084 write(fd: 5<anon_inode:[eventfd]>, buf: 0x7fffe96af0e0, count: 8) = 8
 ^C#

When this option is used the tracer pid is also filtered.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-f5qmiyy7c0uxdm21ncatpeek@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

We need to filter multiple pids in trace, i.e. trace itself,
gnome-terminal, X.org, etc.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-frtpkg7qapqwf7asa35wf8am@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

To avoid tracing the tracer.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-shmwd1khzpaobr3i0j1ygapg@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

To filter out events for a certain pid, for instance, when tracing
system wide, so that the tracer itself doesn't creates an event loop.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-byoia9dzu4gmkdv87etnd9zf@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

When printing just events, i.e. '--no-sys --ev some:events' it makes no
sense to waste screen space.

Before:

 # trace --no-sys --ev probe:*
 84481.704 (         ): probe:vfs_getname:(ffffffff811ed023) pathname="/etc/services")
 84481.892 (         ): probe:vfs_getname:(ffffffff811ed023) pathname="/etc/services")
 84482.230 (         ): probe:vfs_getname:(ffffffff811ed023) pathname="/etc/resolv.conf")
 84482.481 (         ): probe:vfs_getname:(ffffffff811ed023) pathname="/etc/hosts")
 85097.725 (         ): probe:vfs_getname:(ffffffff811ed023) pathname="/root"
 #

After:

 # trace --no-sys --ev probe:*
 0.000 probe:vfs_getname:(ffffffff811ed023) pathname="/root")
 1.711 probe:vfs_getname:(ffffffff811ed023) pathname="/etc/localtime")
 2.103 probe:vfs_getname:(ffffffff811ed023) pathname="/etc/localtime")
^C#

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-jhryxgnam8zecq0q0wsy6pyb@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Pull ARM fix from Russell King:
 "Just one fix this time around.  __iommu_alloc_buffer() can cause a
  BUG() if dma_alloc_coherent() is called with either __GFP_DMA32 or
  __GFP_HIGHMEM set.  The patch from Alexandre addresses this"

* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
  ARM: 8305/1: DMA: Fix kzalloc flags in __iommu_alloc_buffer()

X-Coverup: just ask spender
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

use_pde()/unuse_pde() in ->follow_link()/->put_link() resp.

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

As it is, we have debugfs_remove() racing with symlink traversals.
Supply ->evict_inode() and do freeing there - inode will remain
pinned until we are done with the symlink body.

And rip the idiocy with checking if dentry is positive right after
we'd verified debugfs_positive(), which is a stronger check...

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

I've noticed significant locking contention in memory reclaimer around
sb_lock inside grab_super_passive(). Grab_super_passive() is called from
two places: in icache/dcache shrinkers (function super_cache_scan) and
from writeback (function __writeback_inodes_wb). Both are required for
progress in memory allocator.

Grab_super_passive() acquires sb_lock to increment sb->s_count and check
sb->s_instances. It seems sb->s_umount locked for read is enough here:
super-block deactivation always runs under sb->s_umount locked for write.
Protecting super-block itself isn't a problem: in super_cache_scan() sb
is protected by shrinker_rwsem: it cannot be freed if its slab shrinkers
are still active. Inside writeback super-block comes from inode from bdi
writeback list under wb->list_lock.

This patch removes locking sb_lock and checks s_instances under s_umount:
generic_shutdown_super() unlinks it under sb->s_umount locked for write.
New variant is called trylock_super() and since it only locks semaphore,
callers must call up_read(&sb->s_umount) instead of drop_super(sb) when
they're done.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Fanotify probably doesn't want to watch autodirs so make it use d_can_lookup()
rather than d_is_dir() when checking a dir watch and give an error on fake
directories.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Fix up the following scripted S_ISDIR/S_ISREG/S_ISLNK conversions (or lack
thereof) in cachefiles:

 (1) Cachefiles mostly wants to use d_can_lookup() rather than d_is_dir() as
     it doesn't want to deal with automounts in its cache.

 (2) Coccinelle didn't find S_IS* expressions in ASSERT() statements in
     cachefiles.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Convert the following where appropriate:

 (1) S_ISLNK(dentry->d_inode) to d_is_symlink(dentry).

 (2) S_ISREG(dentry->d_inode) to d_is_reg(dentry).

 (3) S_ISDIR(dentry->d_inode) to d_is_dir(dentry).  This is actually more
     complicated than it appears as some calls should be converted to
     d_can_lookup() instead.  The difference is whether the directory in
     question is a real dir with a ->lookup op or whether it's a fake dir with
     a ->d_automount op.

In some circumstances, we can subsume checks for dentry->d_inode not being
NULL into this, provided we the code isn't in a filesystem that expects
d_inode to be NULL if the dirent really *is* negative (ie. if we're going to
use d_inode() rather than d_backing_inode() to get the inode pointer).

Note that the dentry type field may be set to something other than
DCACHE_MISS_TYPE when d_inode is NULL in the case of unionmount, where the VFS
manages the fall-through from a negative dentry to a lower layer.  In such a
case, the dentry type of the negative union dentry is set to the same as the
type of the lower dentry.

However, if you know d_inode is not NULL at the call site, then you can use
the d_is_xxx() functions even in a filesystem.

There is one further complication: a 0,0 chardev dentry may be labelled
DCACHE_WHITEOUT_TYPE rather than DCACHE_SPECIAL_TYPE.  Strictly, this was
intended for special directory entry types that don't have attached inodes.

The following perl+coccinelle script was used:

use strict;

my @callers;
open($fd, 'git grep -l \'S_IS[A-Z].*->d_inode\' |') ||
    die "Can't grep for S_ISDIR and co. callers";
@callers = <$fd>;
close($fd);
unless (@callers) {
    print "No matches\n";
    exit(0);
}

my @cocci = (
    '@@',
    'expression E;',
    '@@',
    '',
    '- S_ISLNK(E->d_inode->i_mode)',
    '+ d_is_symlink(E)',
    '',
    '@@',
    'expression E;',
    '@@',
    '',
    '- S_ISDIR(E->d_inode->i_mode)',
    '+ d_is_dir(E)',
    '',
    '@@',
    'expression E;',
    '@@',
    '',
    '- S_ISREG(E->d_inode->i_mode)',
    '+ d_is_reg(E)' );

my $coccifile = "tmp.sp.cocci";
open($fd, ">$coccifile") || die $coccifile;
print($fd "$_\n") || die $coccifile foreach (@cocci);
close($fd);

foreach my $file (@callers) {
    chomp $file;
    print "Processing ", $file, "\n";
    system("spatch", "--sp-file", $coccifile, $file, "--in-place", "--no-show-diff") == 0 ||
	die "spatch failed";
}

[AV: overlayfs parts skipped]
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Use d_is_positive() rather than testing dentry->d_inode in SELinux to get rid
of direct references to d_inode outside of the VFS.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Use d_is_positive() rather than testing dentry->d_inode in Smack to get rid of
direct references to d_inode outside of the VFS.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Use d_is_dir() rather than d_inode and S_ISDIR().  Note that this will include
fake directories such as automount triggers.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Use d_is_positive(dentry) or d_is_negative(dentry) rather than testing
dentry->d_inode as the dentry may cover another layer that has an inode when
the top layer doesn't or may hold a 0,0 chardev that's actually a whiteout.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

mediated_filesystem() should use dentry->d_sb not dentry->d_inode->i_sb and
should avoid file_inode() also since it is really dealing with the path.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>