linux-toradex.git/tools/lib/api/fs, branch v4.3-rc6

tools lib api debugfs: Check for tracefs when reporting errors

2015-07-06T15:22:14+00:00

Now that we have two mountpoints, one for debugfs and another, for
tracefs, we end up needing to check permissions for both, so, on
a system with default config we were always asking the user to
check the permission of the debugfs mountpoint, even when it was
already sufficient. Fix it.

E.g.:

  $ trace -e nanosleep usleep 1
  Error: No permissions to read /sys/kernel/debug/tracing/events/raw_syscalls/sys_(enter|exit)
  Hint:  Try 'sudo mount -o remount,mode=755 /sys/kernel/debug'

  $ sudo mount -o remount,mode=755 /sys/kernel/debug
  $ trace -e nanosleep usleep 1
  Error: No permissions to read /sys/kernel/debug/tracing/events/raw_syscalls/sys_(enter|exit)
  Hint:  Try 'sudo mount -o remount,mode=755 /sys/kernel/debug/tracing'

  $ sudo mount -o remount,mode=755 /sys/kernel/debug/tracing
  $ trace -e nanosleep usleep 1
     0.326 ( 0.061 ms): usleep/11961 nanosleep(rqtp: 0x7ffef1081c50) = 0
  $

Cc: Adrian Hunter 
Cc: Borislav Petkov 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Stephane Eranian 
Cc: Steven Rostedt 
Link: http://lkml.kernel.org/n/tip-0viljeuhc7q84ic8kobsna43@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

tools lib api: Rename libapikfs.a to libapi.a

2015-02-12T20:55:18+00:00

Renaming libapikfs.a to libapi.a, because it's not just 'fs' specific
library now.

Signed-off-by: Jiri Olsa 
Tested-by: Sukadev Bhattiprolu 
Tested-by: Will Deacon 
Cc: Alexis Berlemont 
Cc: Borislav Petkov 
Cc: Corey Ashford 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Namhyung Kim 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/n/tip-g1mk5oj2ayq4vn653ovfg3gv@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

tools lib api: Use tools build framework

2015-02-12T20:54:39+00:00

Move the libapikfs library building under tools build framework.

Signed-off-by: Jiri Olsa 
Tested-by: Sukadev Bhattiprolu 
Tested-by: Will Deacon 
Cc: Alexis Berlemont 
Cc: Borislav Petkov 
Cc: Corey Ashford 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Namhyung Kim 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/n/tip-xjo8r7nuqy9mvlfrmx9zcfwb@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

tools lib api fs: Add {tracefs,debugfs}_configured() functions

2015-02-07T13:00:10+00:00

Add tracefs_configured() to return true if tracefs is configured in the
kernel (succeeds to find tracefs), and debugfs_configured() if debugfs
is configured in the kernel (succeeds to find debugfs).

Signed-off-by: Steven Rostedt 
Acked-by: Jiri Olsa 
Cc: Andrew Morton 
Cc: Ingo Molnar 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Link: http://lkml.kernel.org/r/20150202193553.190606690@goodmis.org
Signed-off-by: Arnaldo Carvalho de Melo

tools lib api debugfs: Add DEBUGFS_DEFAULT_PATH macro

2015-02-07T12:56:32+00:00

Instead of hard coding "/sys/kernel/debug" everywhere, create a macro to
hold where the default path exists.

Signed-off-by: Steven Rostedt 
Acked-by: Jiri Olsa 
Cc: Andrew Morton 
Cc: Ingo Molnar 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Link: http://lkml.kernel.org/r/20150202193553.032117017@goodmis.org
Signed-off-by: Arnaldo Carvalho de Melo

tools lib api fs: Add tracefs mount helper functions

2015-02-07T12:55:20+00:00

Since tracefs will now hold the event directory for perf, and even
though by default, debugfs still mounts tracefs on the debugfs/tracing
directory, the system admin may now choose to not mount debugfs and
instead just mount tracefs instead.

Having tracefs helper functions will facilitate having perf look for
tracefs first, and then try debugfs as a fallback.

Signed-off-by: Steven Rostedt 
Acked-by: Jiri Olsa 
Cc: Andrew Morton 
Cc: Ingo Molnar 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Link: http://lkml.kernel.org/r/20150202193552.898934751@goodmis.org
Signed-off-by: Arnaldo Carvalho de Melo

tools lib fs: Add helper to find mounted file systems

2015-02-07T12:51:34+00:00

In preparation for adding tracefs for perf to use, create a findfs
helper utility that find_debugfs uses instead of hard coding the search
in the code. This will allow for a find_tracefs to be used as well.

Signed-off-by: Steven Rostedt 
Acked-by: Jiri Olsa 
Cc: Andrew Morton 
Cc: Ingo Molnar 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Link: http://lkml.kernel.org/r/20150202193552.735023362@goodmis.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Do not check debugfs MAGIC for tracing files

2015-02-07T12:51:30+00:00

It's rather strange to be checking the debugfs MAGIC number for the
tracing directory. A system admin may want to have a custom set of
events to trace and it should be allowed to let the admin make a temp
file (even for tracing virtual boxes, this is useful).

Also with the coming tracefs, the files may not even be under debugfs,
so checking the debugfs MAGIC number is pointless.

Signed-off-by: Steven Rostedt 
Acked-by: Jiri Olsa 
Cc: Andrew Morton 
Cc: Ingo Molnar 
Cc: Masami Hiramatsu 
Cc: Namhyung Kim 
Link: http://lkml.kernel.org/r/20150202193552.546175764@goodmis.org
Signed-off-by: Arnaldo Carvalho de Melo

tools lib fs debugfs: Check if debugfs is mounted when handling ENOENT

2015-01-22T20:02:23+00:00

If debugfs was already mounted, then its a matter of not finding the
tracepoint, tell the user that perhaps a CONFIG_ setting is not enabled.

Cc: Adrian Hunter 
Cc: Borislav Petkov 
Cc: David Ahern 
Cc: Don Zickus 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/n/tip-6chfytoflyx3jwfqm7ebltu0@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

tools lib fs debugfs: Introduce debugfs__strerror_open_tp

2015-01-22T20:02:20+00:00

There will be other cases where not just a tracepoint event is being
opened below the debugfs mountpoint, but it is rather common, so provide
one helper for that.

Cc: Adrian Hunter 
Cc: Borislav Petkov 
Cc: David Ahern 
Cc: Don Zickus 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/n/tip-q6e6zct49ql6nbcw8kkg0lbj@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo