linux-toradex.git/tools/lib/traceevent/event-parse.c, branch v3.14.57

tools lib traceevent: Fix memory leak in pretty_print()

2014-05-31T20:20:27+00:00

commit de04f8657de9d3351a2d5880f1f7080b23b798cf upstream.

Commit 12e55569a244 "tools lib traceevent: Use helper trace-seq in print
functions like kernel does" added a extra trace_seq helper to process
string arguments like the kernel does it. But the difference between the
kernel and the userspace library is that the kernel's trace_seq structure
has a static allocated buffer. The userspace one has a dynamically
allocated one. It requires a trace_seq_destroy(), otherwise it produces
a nasty memory leak.

Signed-off-by: Steven Rostedt 
Link: http://lkml.kernel.org/r/20140422192330.6bb09bf8@gandalf.local.home
Signed-off-by: Jiri Olsa 
Signed-off-by: Greg Kroah-Hartman

tools lib traceevent: Add pevent_unregister_print_function()

2014-01-16T19:26:24+00:00

When a plugin unloaded it needs to unregister its print handler from
pevent.

So add an unregister function to do it.

Signed-off-by: Namhyung Kim 
Reviewed-by: Jiri Olsa 
Acked-by: Steven Rostedt 
Cc: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Steven Rostedt 
Link: http://lkml.kernel.org/r/1389839478-5887-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

tools lib traceevent: Add pevent_unregister_event_handler()

2014-01-16T19:26:24+00:00

When a plugin is unloaded it needs to unregister its handler from pevent.

So add an unregister function to do it.

Signed-off-by: Namhyung Kim 
Reviewed-by: Jiri Olsa 
Acked-by: Steven Rostedt 
Cc: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Steven Rostedt 
Link: http://lkml.kernel.org/r/1389839478-5887-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

tools lib traceevent: Introduce pevent_filter_strerror()

2013-12-18T17:47:58+00:00

The pevent_filter_strerror() function is for receiving actual error
message from pevent_errno value.  To do that, add a static buffer to
event_filter for saving internal error message

If a failed function saved other information in the static buffer
returns the information, otherwise returns generic error message.

Signed-off-by: Namhyung Kim 
Cc: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Peter Zijlstra 
Cc: Steven Rostedt 
Link: http://lkml.kernel.org/r/1386833777-3790-15-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

tools lib traceevent: Report better error message on bad function args

2013-12-06T13:39:54+00:00

When Jiri Olsa was writing a function callback for
scsi_trace_parse_cdb(), he thought that the traceevent library had a
bug in it because he was getting this error:

  Error: expected ')' but read ','
  Error: expected ')' but read ','
  Error: expected ')' but read ','
  Error: expected ')' but read ','

But in truth, he didn't have the write number of arguments for the
function callback, and the error was the library detecting the
discrepancy. A better error message would have prevented the confusion:

  Error: function 'scsi_trace_parse_cdb()' only expects 2 arguments but event scsi_dispatch_cmd_timeout has more
  Error: function 'scsi_trace_parse_cdb()' only expects 2 arguments but event scsi_dispatch_cmd_start has more
  Error: function 'scsi_trace_parse_cdb()' only expects 2 arguments but event scsi_dispatch_cmd_error has more
  Error: function 'scsi_trace_parse_cdb()' only expects 2 arguments but event scsi_dispatch_cmd_done has more

Or

  Error: function 'scsi_trace_parse_cdb()' expects 4 arguments but event scsi_dispatch_cmd_timeout only uses 3
  Error: function 'scsi_trace_parse_cdb()' expects 4 arguments but event scsi_dispatch_cmd_start only uses 3
  Error: function 'scsi_trace_parse_cdb()' expects 4 arguments but event scsi_dispatch_cmd_error only uses 3
  Error: function 'scsi_trace_parse_cdb()' expects 4 arguments but event scsi_dispatch_cmd_done only uses 3

Signed-off-by: Steven Rostedt 
Link: http://lkml.kernel.org/n/tip-a4c34w62vl0diitvxb7bt3er@git.kernel.org
Signed-off-by: Jiri Olsa 
Signed-off-by: Arnaldo Carvalho de Melo

tools lib traceevent: Change pevent_parse_format to include pevent handle

2013-12-04T18:18:42+00:00

Changing the pevent_parse_format interface to include the pevent handle.

The goal is to always use pevent object when dealing with traceevent
library. The reason is that we might need additional processing (like
plugins), which is not possible otherwise.

Patches follow to make this happen completely.

Signed-off-by: Jiri Olsa 
Cc: Corey Ashford 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Namhyung Kim 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Steven Rostedt 
Link: http://lkml.kernel.org/r/1386076182-14484-6-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo

tools lib traceevent: Use helper trace-seq in print functions like kernel does

2013-11-27T17:58:34+00:00

Jiri Olsa reported that his plugin for scsi was chopping off part of the
output. Investigating this, I found that Jiri used the same functions as
what is in the kernel, which adds the following:

	trace_seq_putc(p, 0);

This adds a '\0' to the output string. The reason this works in the
kernel is that the "p" that is passed to the function helper is a
temporary trace_seq. But in the libtraceevent library, it's the pointer
to the trace_seq used to output. By adding the '\0', it truncates the
line and nothing added after that will be printed.

We can solve this in two ways. One is to have the helper functions for
the library not add the unnecessary '\0'. The other is to change the
library to also use a helper trace_seq structure that gets copied to the
main trace_seq just like the kernel does.

The latter allows the helper functions in the plugins to be the same as
the kernel, which is the better solution.

Signed-off-by: Steven Rostedt 
Reported-by: Jiri Olsa 
Tested-by: Jiri Olsa 
Cc: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: http://lkml.kernel.org/r/20131119182937.401668e3@gandalf.local.home
Signed-off-by: Arnaldo Carvalho de Melo

tools lib traceevent: Fix conversion of pointer to integer of different size

2013-11-19T19:37:59+00:00

gcc complaint on 32-bit system:

  /home/acme/git/linux/tools/lib/traceevent/event-parse.c: In function ‘eval_num_arg’:
  /home/acme/git/linux/tools/lib/traceevent/event-parse.c:3468:9: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]

This is because the eval_num_arg returns everything as an 'unsigned long long',
so it converts a void pointer to a wider integer, fix it by converting the void
pointer to an integer of the same size, 'unsigned long', before casting it to
'unsigned long long'.

Acked-by: Steven Rostedt 
Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Mike Galbraith 
Cc: Namhyung Kim 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/n/tip-yllx4aqcg06v5n4vjpwiiuld@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

tools lib traceevent: Fix use of multiple options in processing field

2013-11-19T13:34:39+00:00

Jiri Olsa reported that the scsi_dispatch_cmd_done event failed to parse
with:

  Error: expected type 5 but read 4
  Error: expected type 5 but read 4

The problem is with this part of the print_fmt:

  __print_symbolic(((REC->result) >> 24) & 0xff, ...

The __print_symbolic() helper function's first parameter is the field to
use to determine what symbol to print based on the value of the result.
The parser can handle one operation, but it can not handle multiple
operations ('>>' and '&').

Add code to process all operations for the field argument for
__print_symbolic() as well as __print_flags().

Reported-by: Jiri Olsa 
Signed-off-by: Steven Rostedt 
Cc: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: http://lkml.kernel.org/r/20131118142314.27ca334b@gandalf.local.home
Signed-off-by: Arnaldo Carvalho de Melo

tools lib traceevent: Add direct access to dynamic arrays

2013-11-12T20:23:44+00:00

Jiri Olsa was writing a plugin for the cfg80211_tx_mlme_mgmt trace
event, and was not able to get the implemented function working.
The event's print fmt looks like:

   "netdev:%s(%d), ftype:0x%.2x", REC->name, REC->ifindex,
            __le16_to_cpup((__le16 *)__get_dynamic_array(frame))

As there's no helper function for __le16_to_cpup(), Jiri was creating one
with a plugin. But unfortunately, it would not work even though he set
up the plugin correctly.

The problem is that the function parameters do not handle the helper
function "__get_dynamic_array()", and that passes in a NULL pointer.

Adding PRINT_DYNAMIC_ARRAY direct support to eval_num_arg() allows the
use of __get_dynamic_array() in function parameters.

Reported-by: Jiri Olsa 
Signed-off-by: Steven Rostedt 
Tested-by: Jiri Olsa 
Cc: Frederic Weisbecker 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: http://lkml.kernel.org/r/20131111160810.0ba9df7d@gandalf.local.home
Signed-off-by: Arnaldo Carvalho de Melo