This allows passing a timer to be run periodically, which will update
the hists tree that then gers refreshed on the screen, just like the
Live mode (symbol entries, annotation) we already have in 'perf top
--tui'.

Will be used by the new hist_entry/hists based 'top' tool.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-2r44qd8oe4sagzcgoikl8qzc@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Now it warns everytime that new events are lost.

And the TUI also warns now.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-w1n168yrvrppnq6887s4u0wx@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Fixing an artifact where the last 3 chars of a long DSO name would
remain on the screen sometimes.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-dkiakcl3z69dh1bt9uegaktv@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

It will be immediately replaced in perf_top_browser__run.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-q7e2jzb44elqpkvdllk94x0i@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Fixing a SEGV. An empty list could happen when not being able to resolve
symbols, for instance when --vmlinux invalid-file is used.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The left key was exiting 'perf top --tui' when it really shouldn't, it
was too easy to leave the live annotation window and then press one too
many <- and get out of the tool altogether.

Do just like the report TUI does, ignore the left key for exit and also
ask the user when pressing ESC if that is really what is wanted.
Reported-by: NMike Galbraith <efault@gmx.de>
Suggested-by: NIngo Molnar <mingo@elte.hu>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This is not a problem when we're not at the bottom of the active symbols
list, so was not noticed, but at the end of the screen it falls apart.

Fix it by adjusting the ui_browser indexes according to the new number
of entries in the rb_tree and by seeking from the start of the rb_tree
to find the new symbol at the top of the screen.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Now one has just to press the right key, 'a' or Enter on the main 'perf
top --tui' screen to live annotate the symbol under the cursor.

The annotate window starts centered on the hottest line (the one with
most samples so far) then TAB and shift+TAB can be used to go to the
prev/next hot line.

Pressing 'H' at any point will center again the screen on the hottest
line.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Disabled by default as there are features found in the stdio based one
that aren't implemented, like live annotation, filtering knobs data
entry.

Annotation hopefully will get somehow merged with the 'perf annotate'
code.

To use it:

perf top --tui

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>