Hi Chris,
Please review an updated version of the fix that makes the tests to use a
custom pattern while waiting for the command to complete.
Webrev: http://cr.openjdk.java.net/~dtitov/8211736/webrev.05/
Issue: https://bugs.openjdk.java.net/browse/JDK-8211736
Thanks!
--Daniil
On 10/19/18, 12:55 PM, "Chris Plummer" <chris.plum...@oracle.com> wrote:
On 10/19/18 9:47 AM, Daniil Titov wrote:
> Hi Gary and Chris,
>
> I am resending the previous email since the table in that email got
corrupted.
>
> Below is what output jdb prints when a breakpoint is hit depending on
what suspended policy is used:
>
> The current behavior.
> SUSPEND_ALL: Prompt is printed ( e.g. "main[1]"), location is printed
> SUSPEND_EVENT_THREAD: Prompt is not printed, location is not printed
> SUSPEND_NONE: Prompt is not printed, location is not printed
>
> The fix changes this behavior as the following:
>
> SUSPEND_ALL: Prompt is printed ( e.g. "main[1]"), location is printed
> SUSPEND_EVENT_THREAD: Prompt is printed ( "> "), location is printed
> SUSPEND_NONE: Prompt is printed ( "> "), location is printed
I'm still in favor of this fix.
>
>
> Could you please say is it OK for you or you want that the location was printed
only for SUSPEND_ALL case? Or probably just leave all behavior unchanged and close the bug
as "not an issue"?
>
> Regarding settable prompt... As I understand Gary's original concern was that waiting in
tests for a simple prompt " > " (> ) could be unreliable if this
substring somehow appears in the output of the test program and the suggestion was to use more specific
patterns for the cases when the full prompt (thread_name[frame_index]) is not printed ( e.g. when the
current thread is not set). However, we need somehow pass this pattern to Jdb.command(JdbCommand)
method otherwise it would keep waiting for the full prompt and fail with the timeout. Probably I am
missing something here...
Maybe we need a version of command() that takes a pattern to look for
other than the prompt.
Chris
>
>
> Thanks!
> --Daniil
>
> On 10/19/18, 9:27 AM, "Daniil Titov" <daniil.x.ti...@oracle.com> wrote:
>
> Hi Gary and Chris,
>
> Below is the table that shows what jdb output is printed when a
breakpoint is hit depending on what suspended policy is used:
>
> SUSPEND POLICY | PROMPT PRINTED | LOCATION
PRINTED
> ---------------------------------------
|---------------------------|--------------------------
> SUSPEND_ALL. | yes, e.g. "main[1]" |
yes
> --------------------------------------- |--------------------------
|--------------------------
> SUSPEND_EVENT_THREAD | no | no
> ----------------------------------------|------------------------
--|--------------------------
> SUSPEND_ALL. | no
| no
>
>
> The fix changes this behavior as the following:
>
> SUSPEND POLICY | PROMPT PRINTED. | LOCATION
PRINTED
> ---------------------------------------
|----------------------------|--------------------------
> SUSPEND_ALL. | yes , e.g. "main[1]" |
yes
> ---------------------------------------
|----------------------------|--------------------------
> SUSPEND_EVENT_THREAD | yes , ">" |
yes
>
----------------------------------------|---------------------------
|--------------------------
> SUSPEND_ALL. | yes, ">".
| yes
>
> Could you please say is it OK for you or you want that the location was
printed only for SUSPEND_ALL case? Or probably just leave all behavior unchanged and close
the bug as "not an issue"?
>
> Regarding settable prompt... As I understand Gary's original concern was that waiting
in tests for a simple prompt " > " (> ) could be unreliable if this
substring somehow appears in the output of the test program and the suggestion was to use more specific
patterns for the cases when the full prompt (thread_name[frame_index]) is not printed ( e.g. when the
current thread is not set). However, we need somehow pass this pattern to Jdb.command(JdbCommand)
method otherwise it would keep waiting for the full prompt and fail with the timeout. Probably I am
missing something here...
>
>
> Thanks!
>
> Best regards,
> Daniil
>
>
>
> On 10/19/18, 12:54 AM, "gary.ad...@oracle.com"
<gary.ad...@oracle.com> wrote:
>
> It's not clear to me if the omitted location information for
the non
> stopping
> cases was intentional or not. It may be sufficient to know that
the
> event fired
> without the extra information.
>
> I don't think a settable prompt is required either. There are
plenty of
> jdb commands that
> could be used with the wait for message in tests that need to
> synchronize at a specific
> point in the test sequence.
>
> I don't think we see wait for simple prompt in any of the
tests, because it
> is not reliable enough.
>
> On 10/18/18 11:53 AM, Daniil Titov wrote:
> > Hi Gary,
> >
> > Currently when a breakpoint is hit the message "Breakpoint hit:" is
printed in the debugger output. What we do in this fix we just add more information about what exact
breakpoint is hit. Do you suggest we should not print this line at all if suspend policy is SUSPEND_NONE?
If so then it is not clear what is the use of the command "stop go ..." would be. Regarding
waiting for the simple prompt, we could change JDbCommand to have a field to store a prompt pattern and
use this pattern (if it was set) when waiting for command to complete. In tests when required we would
set the pattern in JdbCommand to more complicated one matching a specific output we are expecting at this
particular step. Do you think it would be a better approach?
> >
> > Thanks!
> >
> > Best regards,
> > Daniil
> >
> >
> >
> > On 10/18/18, 4:09 AM, "Gary Adams" <gary.ad...@oracle.com>
wrote:
> >
> > I'm not certain that we should be printing locations or
prompts for
> > events when the vm has not been suspended. This looks OK
for the
> > simple test case we are working on here, but in real
life there may
> > be a lot more output produced.
> >
> > The user has to select a specific thread before
additional commands
> > can be performed in the correct context. e.g. threads,
thread n, where, ...
> > So the information is available to the user. It doesn't
have to be
> > produced at the time the event is processed.
> >
> > I'm uncomfortable putting too much trust in waiting for
the simple prompt,
> > because there is too great a chance of false positives
on such a small
> > marker.
> >
> >
> > On 10/17/18, 8:50 PM, Daniil Titov wrote:
> > > Hi Chris, Alex and JC,
> > >
> > > I created a separate issue to deal with "non-atomic"
jdb output at https://bugs.openjdk.java.net/browse/JDK-8212626 .
> > >
> > > Please review an updated fix that includes the changes
Alex suggested.
> > >
> > > Webrev:
http://cr.openjdk.java.net/~dtitov/8211736/webrev.04
> > > Issue: https://bugs.openjdk.java.net/browse/JDK-8211736
> > >
> > > Thanks!
> > > --Daniil
> > >
> > >
> > > On 10/17/18, 5:06 PM, "Daniil
Titov"<daniil.x.ti...@oracle.com> wrote:
> > >
> > > Hi Chris,
> > >
> > > The previous email was accidentally fired before
I managed to type anything in. Sorry for confusion.
> > >
> > > Jdb constantly reads new commands from System.in
despite whether the breakpoint is hit and/or the prompt is printed.
> > >
> > > cat -n
src/jdk.jdi/share/classes/com/sun/tools/example/debug/tty/TTY.java
> > >
> > > 786 // Process interactive
commands.
> > > 787 MessageOutput.printPrompt();
> > > 788 while (true) {
> > > 789 String ln =
in.readLine();
> > > 790 if (ln == null) {
> > > 791 /*
> > > 792 * Jdb is being
shutdown because debuggee exited, ignore any 'null'
> > > 793 * returned by
readLine() during shutdown. JDK-8154144.
> > > 794 */
> > > 795 if
(!isShuttingDown()) {
> > > 796
MessageOutput.println("Input stream closed.");
> > > 797 }
> > > 798 ln = "quit";
> > > 799 }
> > > 800
> > > 801 if
(ln.startsWith("!!")&& lastLine != null) {
> > > 802 ln = lastLine +
ln.substring(2);
> > > 803
MessageOutput.printDirectln(ln);// Special case: use printDirectln()
> > > 804 }
> > > 805
> > > 806 StringTokenizer t = new
StringTokenizer(ln);
> > > 807 if (t.hasMoreTokens()) {
> > > 808 lastLine = ln;
> > > 809 executeCommand(t);
> > > 810 } else {
> > > 811
MessageOutput.printPrompt();
> > > 812 }
> > > 813 }
> > > 814 } catch (VMDisconnectedException
e) {
> > > 815
handler.handleDisconnectedException();
> > > 816 }
> > >
> > > Below is a sample debug session for the following test class that
sends commands "threads" and "quit"
> > > 1 public class LoopTest {
> > > 2 public static void main(String[]
args) throws Exception {
> > > 3 Thread thread =
Thread.currentThread();
> > > 4 while(true) {
> > > 5 print(thread);
> > > 6 Thread.sleep(5000);
> > > 7 }
> > > 8 }
> > > 9
> > > 10 public static void print(Object obj)
{
> > > 11 //System.out.println(obj);
> > > 12 }
> > > 13 }
> > >
> > > datitov-mac:work datitov$
~/src/jdk-hs/build/macosx-x64-debug/images/jdk/bin/jdb LoopTest
> > > Initializing jdb ...
> > > > stop go at LoopTest:6
> > > Deferring breakpoint LoopTest:6.
> > > It will be set after the class is loaded.
> > > > run
> > > run LoopTest
> > > Set uncaught java.lang.Throwable
> > > Set deferred uncaught java.lang.Throwable
> > > >
> > > VM Started: Set deferred breakpoint LoopTest:6
> > >
> > > Breakpoint hit: "thread=main", LoopTest.main(),
line=6 bci=8
> > > 6 Thread.sleep(5000);
> > >
> > > Breakpoint hit: "thread=main", LoopTest.main(),
line=6 bci=8
> > > 6 Thread.sleep(5000);
> > > threads
> > > Group system:
> > > (java.lang.ref.Reference$ReferenceHandler)0x172
Reference Handler running
> > > (java.lang.ref.Finalizer$FinalizerThread)0x173
Finalizer cond. waiting
> > > (java.lang.Thread)0x174
Signal Dispatcher running
> > > Group main:
> > > (java.lang.Thread)0x1
main sleeping
> > > Group InnocuousThreadGroup:
> > > (jdk.internal.misc.InnocuousThread)0x197
Common-Cleaner cond. waiting
> > > >
> > > Breakpoint hit: "thread=main", LoopTest.main(),
line=6 bci=8
> > > 6 Thread.sleep(5000);
> > >
> > > Breakpoint hit: "thread=main", LoopTest.main(),
line=6 bci=8
> > > 6 Thread.sleep(5000);
> > > quit
> > > Breakpoint hit: "thread=main", LoopTest.main(),
line=6 bci=8
> > > 6 Thread.sleep(5000);
> > >
> > > datitov-mac:work datitov$
> > >
> > > I think we could print a simple prompt in this
case as Alex suggested.
> > >
> > > Best regards,
> > > Daniil
> > >
> > > On 10/17/18, 3:52 PM, "Chris
Plummer"<chris.plum...@oracle.com> wrote:
> > >
> > > What is the jdb state for a breakpoint with
SUSPEND_NONE? Can you
> > > actually type in commands even though no
threads are suspended?
> > >
> > > Chris
> > >
> > > On 10/17/18 3:31 PM, Alex Menkov wrote:
> > > > Hi Daniil, Chris,
> > > >
> > > > As far as I understand, the fix does not
completely fixes all
> > > > "non-atomic" output issues (at least
TTY.executeCommand still prints
> > > > prompt separately), so I agree that handle
it as separate issue would
> > > > be better.
> > > > Unfortunately I don't know Gary's ideas
for the issue.
> > > >
> > > > About the fix for print prompt:
> > > > 1) TTY.java:
> > > > + // Print current location if
suspend policy is SUSPEND_NONE
> > > > I suppose you mean "Print breakpoint
location"
> > > >
> > > > 2) Does it make sense to use
printCurrentLocation for
> > > > SUSPEND_EVENT_THREAD?
> > > > Is it expected to print something
different from printBreakpointLocation?
> > > >
> > > > 3) I don't quite understand why we don't
print simple prompt for
> > > > SUSPEND_NONE. IIUC jdb can accept new
command in both
> > > > SUSPEND_EVENT_THREAD and SUSPEND_NONE
cases (prompt shows that jdb
> > > > waits for next command, right?)
> > > >
> > > > 4) JdbStopThreadTest.java
> > > > New line line in Java regexp is "\\R"
> > > >
> > > > --alex
> > > >
> > > > On 10/17/2018 10:47, Chris Plummer wrote:
> > > >> Hi Alex,
> > > >>
> > > >> I think the tty buffering should be a
separate bug fix, and I'd also
> > > >> like input from Gary on it since he had
tried something similar at
> > > >> one point. It should probably also
include a multithread test to
> > > >> prove the fix is working (after first
getting the test to fail
> > > >> without the changes).
> > > >>
> > > >> thanks,
> > > >>
> > > >> Chris
> > > >>
> > > >> On 10/16/18 8:59 PM, Daniil Titov wrote:
> > > >>> Hi Alex, Chris and JC,
> > > >>>
> > > >>> Please review an updated version of the
patch that addresses these
> > > >>> issues.
> > > >>>
> > > >>> Webrev:
http://cr.openjdk.java.net/~dtitov/8211736/webrev.03/
> > > >>> Issue:
https://bugs.openjdk.java.net/browse/JDK-8211736
> > > >>>
> > > >>> Thanks!
> > > >>> --Daniil
> > > >>>
> > > >>>
> > > >>> On 10/12/18, 9:52 AM, "Alex
Menkov"<alexey.men...@oracle.com> wrote:
> > > >>>
> > > >>> Hi Daniil,
> > > >>> 1) +1 for printCurrentLocation when
suspendPolicy != SUSPEND_ALL
> > > >>> 2) wrong indent in
JdbStopThreadTest.java:
> > > >>> 36 import
lib.jdb.JdbCommand;
> > > >>> 37 import
lib.jdb.JdbTest;
> > > >>> 3) I think it would be better to
make waitForSimplePrompt
> > > >>> property of
> > > >>> JdbCommand (like
JdbCommand.allowExit)
> > > >>>
jdb.command(JdbCommand.run().replyIsSimplePrompt());
> > > >>> looks much clearer than
> > > >>> jdb.command(JdbCommand.run(), true);
> > > >>> 4) (TTY.java)
> > > >>> MessageOutput.lnprint("Breakpoint
hit:");
> > > >>> + // Print current location and
prompt if suspend policy is
> > > >>> SUSPEND_EVENT_THREAD.
> > > >>> + // In case of SUSPEND_ALL policy
this is handled by
> > > >>> vmInterrupted()
> > > >>> method.
> > > >>> + if (be.request().suspendPolicy()
==
> > > >>> EventRequest.SUSPEND_EVENT_THREAD) {
> > > >>> +
printCurrentLocation(ThreadInfo.getThreadInfo(be.thread()));
> > > >>> + MessageOutput.printPrompt();
> > > >>> + }
> > > >>> We have 3 separate outputs.
> > > >>> If we have several concurrent
threads, we can easy get mess of
> > > >>> outputs
> > > >>> from different threads.
> > > >>> I think it would be better to print
everything in a single chunk.
> > > >>> I suppose TTY has other places with similar
"non-atomic"
> > > >>> output, so
> > > >>> maybe revising TTY output should be
handled by separate issue.
> > > >>> --alex
> > > >>> On 10/11/2018 22:00, Chris Plummer
wrote:
> > > >>> > Hi Daniil,
> > > >>> >
> > > >>> > Can you send output from an
example jdb session?
> > > >>> >
> > > >>> > Do you think maybe we should
also call printCurrentLocation()
> > > >>> when the
> > > >>> > suspend policy is NONE?
> > > >>> >
> > > >>> > There's a typo in the following
line. The space is on the
> > > >>> wrong side of
> > > >>> > the comma.
> > > >>> >
> > > >>> > 72
jdb.command(JdbCommand.stopThreadAt(DEBUGGEE_CLASS
> > > >>> ,bpLine));
> > > >>> >
> > > >>> > thanks,
> > > >>> >
> > > >>> > Chris
> > > >>> >
> > > >>> > On 10/11/18 8:02 PM, Daniil
Titov wrote:
> > > >>> >>
> > > >>> >> Thank you, JC!
> > > >>> >>
> > > >>> >> Please review an updated
version of the patch that fixes
> > > >>> newly added
> > > >>> >> test for Windows platform (now
it uses system dependent line
> > > >>> >> separator string).
> > > >>> >>
> > > >>> >>
Webrev:http://cr.openjdk.java.net/~dtitov/8211736/webrev.02/
> > > >>> >>
<http://cr.openjdk.java.net/%7Edtitov/8211736/webrev.02/>
> > > >>> >>
> > > >>> >> Issue:
https://bugs.openjdk.java.net/browse/JDK-8211736
> > > >>> >>
> > > >>> >> Best regards,
> > > >>> >>
> > > >>> >> --Daniil
> > > >>> >>
> > > >>> >> *From: *JC
Beyler<jcbey...@google.com>
> > > >>> >> *Date: *Thursday, October 11,
2018 at 7:17 PM
> > > >>> >> *To:
*<daniil.x.ti...@oracle.com>
> > > >>> >> *Cc:
*<serviceability-dev@openjdk.java.net>
> > > >>> >> *Subject: *Re: RFR 8211736: jdb
doesn't print prompt when
> > > >>> breakpoint
> > > >>> >> is hit and suspend policy is
STOP_EVENT_THREAD
> > > >>> >>
> > > >>> >> Hi Daniil,
> > > >>> >>
> > > >>> >> Looks good to me. I saw a
really small nit:
> > > >>> >>
> > > >>> >>
> > > >>>
http://cr.openjdk.java.net/~dtitov/8211736/webrev.01/test/jdk/com/sun/jdi/JdbStopThreadTest.java.html
> > > >>>
> > > >>> >>
> > > >>>
<http://cr.openjdk.java.net/%7Edtitov/8211736/webrev.01/test/jdk/com/sun/jdi/JdbStopThreadTest.java.html>
> > > >>>
> > > >>> >>
> > > >>> >> 70
jdb.command(JdbCommand.stopThreadAt( DEBUGGEE_CLASS
> > > >>> ,bpLine));
> > > >>> >>
> > > >>> >> There is a space after the '('.
> > > >>> >>
> > > >>> >> No need to send a new webrev
for that evidently :),
> > > >>> >>
> > > >>> >> Jc
> > > >>> >>
> > > >>> >> On Thu, Oct 11, 2018 at 5:07 PM
Daniil Titov
> > > >>> >> <daniil.x.ti...@oracle.com
> > > >>> <mailto:daniil.x.ti...@oracle.com>>
wrote:
> > > >>> >>
> > > >>> >> Please review the change
that fixes the issue with
> > > >>> missing prompt
> > > >>> >> in jdb when a breakpoint is
hit and the suspend policy
> > > >>> is set to
> > > >>> >> stop the thread only.
> > > >>> >>
> > > >>> >> Webrev:
> > > >>>
http://cr.openjdk.java.net/~dtitov/8211736/webrev.01
> > > >>> >>
<http://cr.openjdk.java.net/%7Edtitov/8211736/webrev.01>
> > > >>> >> Issue:
https://bugs.openjdk.java.net/browse/JDK-8211736
> > > >>> >>
> > > >>> >> Thanks!
> > > >>> >> --Daniil
> > > >>> >>
> > > >>> >>
> > > >>> >>
> > > >>> >> --
> > > >>> >>
> > > >>> >> Thanks,
> > > >>> >>
> > > >>> >> Jc
> > > >>> >>
> > > >>> >
> > > >>>
> > > >>>
> > > >>
> > > >>
> > >
> > >
> > >
> > >
> > >
> >
> >
> >
> >
>
>
>
>
>
