Add snapshot howto

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Version 2.3.0-rc2

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Add core-handler README to dist tarball

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

extras: core-handler: simplify, allow usage from tracing group

Allow managing the coredump handler tracing session from the tracing
group. Use create --snapshot.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Cleanup: add missing dot

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: documentation: create name and options

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Add core dump snapshot handler script

This is a custom core dump program that will be called when a core dump
occurs.  The program will save the core data in CORE_PATH and also, if a
root session daemon is running, will record a snapshot of tracing data
using the lttng command line utility.

Refer to README for installation and testing instructions.

Sample output of test script:

Setup...
Spawning a session daemon
Session auto-20130626-224838 created.
Kernel channel chan enabled for session auto-20130626-224838
kernel event sched_switch created in channel chan
Tracing started for session auto-20130626-224838
Sleeping...
Crashing...
./test.sh: line 35: 16980 Segmentation fault      (core dumped)
$(dirname $0)/crash
Waiting for data availability
Tracing stopped for session auto-20130626-224838
Session auto-20130626-224838 destroyed
Core dump and snapshot will be available in /tmp/lttng/{core,snapshot}.

/tmp/lttng
|-- core
|   `-- core.16980
`-- snapshot
    `-- snapshot
        |-- chan_0
        |-- chan_1
        |-- chan_2
        |-- chan_3
        |-- chan_4
        |-- chan_5
        |-- chan_6
        |-- chan_7
        `-- metadata

Signed-off-by: Christian Babeux <christian.babeux@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: sym name len (kernel)

Use kernel and not UST sym name len for kernel tracing. Fixed build when
UST is disabled.

Fix bug introduced in 2.3-rc dev cycle by:

commit 850767541647c102a299d7fbc39c97555ac70224
Author: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date:   Fri Jul 19 09:04:29 2013 -0400

    Fix: (slight UI change) refuse missing -c if non-default channel exists

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: tests: provide channel name when a non-default channel exists: per-pid

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: tests: provide channel name when a non-default channel exists

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: data pending race

There is a data pending race involving late population of the streams in
the stream hash table, and applying flush on streams that are not yet
globally visible.

This is caused by the fact that streams are added to the hash table only
when received by the data-handling consumer thread.

This results in data_pending() incorrectly returning that there is no
data pending in some cases.

This has been discovered by adding 1s delay in read subbuffer function
for testing.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix hang in make check snapshots/test_ust

Missing a kill of the test app at the end of
test_ust_1000_local_snapshots.

Signed-off-by: Julien Desfossez <jdesfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Cleanup: ust-consumer: wrong indentation

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: print dots while waiting for data availability

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: remove sleep(1) added by "Fix: (slight UI change) refuse missing -c if non-default channel exists"

For debugging, added by mistake.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: (slight UI change) refuse missing -c if non-default channel exists

After a user creates a channel within a session, creating a "default"
channel if a user forgets to put "-c channel_name" in the following
add-context, enable-event, disable-event commands is misleading.  The
natural expected behavior would be that the command would apply the the
last enabled channel (notion of a "current" channel, like we have for
sessions), but certainly not that it creates a new channel with default
attributes behind the user's back.

An intermediate fix that would not require to keep a notion of current
channel is to refuse creation of a default channel if at least one
non-default channel has already been created in the session.

This commit affects enable-event, disable-event and add-context
commands.

This fix belongs to the 2.3-rc cycle, and cannot be backported, since
it:

a) changes the user interface of lttng (returns an error in the case
   where -c name is missing and the session contains an non-default
   channel)
b) changes the ABI between lttng-ctl and sessiond: a default channel is
   now expressed as an empty string ('\0') rather than by "channel0",
   which allows making the difference between an explicit "channel0"
   channel and a default channel in the session daemon.

Fixes #522

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: push metadata on stop for per-UID buffers

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

README: update python documentation

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Manpage: other layout cleanups

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Manpage: cleanup layout of view

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Manpage: cleanup layout of version

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Manpage: cleanup layout of stop

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Manpage: cleanup layout of start

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Manpage: cleanup layout of snapshot

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Manpage: cleanup layout of set-session

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Manpage: cleanup layout of list

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Manpage: cleanup layout of disable-event

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Manpage: cleanup layout of disable-channel

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Manpage: cleanup layout of enable-event

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Manpage: cleanup layout of enable-channel

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Manpage: cleanup layout of destroy

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Manpage: cleanup layout of create

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Manpage: cleanup layout of calibrate

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Manpage: cleanup layout of add-context

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Documentation: create --snapshot in manpage

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Version 2.3.0-rc1

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: add missing snapshot header to dist tarball

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Documentation: fix thread quit pipe comment

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Test for presence of bison and flex when building from git

[ Update by Mathieu Desnoyers: handle VPATH build from tarball
  by prefixing path with $srcdir. ]

Signed-off-by: Yannick Brosseau <yannick.brosseau@gmail.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Test UST snapshot with large metadata

Signed-off-by: Julien Desfossez <jdesfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Add test application with large metadata

This application generates 5 tracepoints with a lot of parameters. The
resulting metadata is >12kB which is useful to test the behaviour of the
UST metadata cache and the flushing mechanism when there is more than
one metadata packet.

Signed-off-by: Julien Desfossez <jdesfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Cleanup: remove redundant assignment

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: use per-uid buffer registry for UID buffer snapshots

Fixes empty traces when doing a snapshot after killing a single traced
application.

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

cmd.c: fix typos in snapshot commands

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Test snapshot per-uid post-mortem

Test to check if we can take a snapshot after a traced application
exited when using per-uid buffers.

Signed-off-by: Julien Desfossez <jdesfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Remove leftover fprintf

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix deadlock: don't take channel lock in timer

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Introduce channel timer lock

Currently a shadow of the channel lock. Will eventually be used to
protect channel timer handler from concurrent channel updates without
being held when the timer is stopped (future commit).

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

document lttng_ustconsumer_request_metadata locking constraints

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

consumer: remove unused lttng_ustconsumer_push_metadata

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Document metadata_socket_lock nesting

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

lttng_ustconsumer_recv_metadata does not need all those locks

Since lttng_ustconsumer_recv_metadata() does not push data into the
stream anymore, it only needs the metadata cache lock.

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

document metadata_switch_timer() deadlock

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: add missing metadata socket lock

Protect metadata socket, which can be accessed concurrently by the
metadata timer and by snapshot.

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

document metadata_switch_timer() locking constraints

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

consumer: remove timeout for UST metadata

Remove time out for UST metadata by generating metadata packets whenever
they are about to be read from the ring buffer rather than filling them
when the metadata cache is updated, which requires a time out, and
therefore may fail.

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Introduce pipe for UST metadata cache and stream

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

consumer: replace DBG2() instances by DBG()

The consumer daemon does not currently support DBG2() printout.

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Introduce utils_create_pipe_cloexec_nonblock()

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

ust consumer: data_pending check is endpoint active

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: kernel consumer: data_pending check if endpoint active

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

consumer: explicitly set endpoint status to active at init

Ensures we explicitly set active at init for channels that don't
interact with a relayd.

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

document consumer_metadata_cache_flushed use of consumer_data.lock

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

consumer: introduce channel lock

Reviewed-by: Julien Desfossez <julien.desfossez@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Merge branch 'master' of git://git.lttng.org/lttng-tools

Fix: update lttng snapshot help output

Signed-off-by: David Goulet <dgoulet@efficios.com>

Man: fix part of snapshot documentation

Signed-off-by: David Goulet <dgoulet@efficios.com>

Fix: set tracefile size test with PID buffers

Signed-off-by: David Goulet <dgoulet@efficios.com>

Fix: Babelstats fail to parse output with no process name or pid

The process name and pid are optionnal components in the babeltrace
text output.

Signed-off-by: Christian Babeux <christian.babeux@efficios.com>

Missing NULL pointer init in tap.c

Could lead to free() of unitialized pointer.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: David Goulet <dgoulet@efficios.com>

Fix: Unchecked asprintf/vasprintf return values

strp may be modified even in case of failure according to the
ASPRINTF(3) man page.

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Signed-off-by: David Goulet <dgoulet@efficios.com>

Add snapshots test to fast regression

Signed-off-by: David Goulet <dgoulet@efficios.com>

Fix: kernel data unit test

Signed-off-by: David Goulet <dgoulet@efficios.com>

Fix: snapshot returned valid LTTNG_ERR code

Signed-off-by: David Goulet <dgoulet@efficios.com>

Add the number of snapshot taken to the output path

This number of snapshots is per session.

Signed-off-by: David Goulet <dgoulet@efficios.com>

Fix: RCU read side lock unbalanced

Signed-off-by: David Goulet <dgoulet@efficios.com>

Fix: zeroed snapshot output at init

Signed-off-by: David Goulet <dgoulet@efficios.com>

Support del-output with an output name

Signed-off-by: David Goulet <dgoulet@efficios.com>

Update man page with snapshot command

Signed-off-by: David Goulet <dgoulet@efficios.com>

New UST default buffers is now per UID

Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: David Goulet <dgoulet@efficios.com>

Bump UST ABI major version for 2.3 release

Signed-off-by: David Goulet <dgoulet@efficios.com>

Add snapshot mode to lttng list session

Signed-off-by: David Goulet <dgoulet@efficios.com>

Fix: support temporary snapshot max size and name

Signed-off-by: David Goulet <dgoulet@efficios.com>

Support snapshot max-size limitation

This features allows the user to specify a maximum size for the snapshot
collected. The maximum stream size is split equally by the total number
of streams active at the time of the snapshot record across all the
domains. The metadata is not limited and its size is not taken into
account in the maximum stream size computation.

Signed-off-by: Julien Desfossez <jdesfossez@efficios.com>
Signed-off-by: David Goulet <dgoulet@efficios.com>

Tests: per-UID UST snapshot

Signed-off-by: Julien Desfossez <jdesfossez@efficios.com>
Signed-off-by: David Goulet <dgoulet@efficios.com>

Fix: snapshot support for UST and kernel in same session

Signed-off-by: David Goulet <dgoulet@efficios.com>

Implement lttng create --snapshot command

This is to ease the life of the user creating a session in snapshot
mode using the new API call.

Signed-off-by: David Goulet <dgoulet@efficios.com>

Add create session snapshot API in lttng-sessiond

This commit adds the "lttng_create_session_snapshot()" call to the API
which will create on the session daemon a session in snapshot mode
meaning that all channel will be in overwrite mode and mmap output.

Signed-off-by: David Goulet <dgoulet@efficios.com>

Add snapshot output init call that uses URIs

Signed-off-by: David Goulet <dgoulet@efficios.com>

Fix: consumer err_sock cloexec

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: David Goulet <dgoulet@efficios.com>

Callsite: add "ip" context

Support ip context in lttng add-context -t.

Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: David Goulet <dgoulet@efficios.com>

Fix: possible consumer sockets double close on cleanup

Signed-off-by: David Goulet <dgoulet@efficios.com>

Automatically load kvm-x86 and kvm-x86-mmu probes.

Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Mohamad Gebai <mohamad.gebai@polymtl.ca>
Signed-off-by: David Goulet <dgoulet@efficios.com>

Fix: consumer: use uint64_t for all sessiond_id

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: add gpl and lgpl files to tarball

Fixes #581

Signed-off-by: David Goulet <dgoulet@efficios.com>

Fix: don't install libtap system wide

Signed-off-by: David Goulet <dgoulet@efficios.com>

Fix: close consumer sockets in sessiond cleanup

Signed-off-by: David Goulet <dgoulet@efficios.com>

Fix: set globally visible flag to kernel stream

Signed-off-by: David Goulet <dgoulet@efficios.com>

Fix: lttng: memory leak in snapshot record command

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: kernel-consumer: double-close

check for -1 out_fd

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>