SoW-2019-0007-2: Dynamic Snapshot: Triggers send partial event payload with notifications

Revision 1

Change-Id: I7455c9fced2dc98c7048ef0d1608db519087171c

Fix: syscalls: Ignore fcntl cmd specific to 32-bit in 64-bit only config

When CONFIG_64BIT is defined and CONFIG_COMPAT is not defined, the fcntl system call
"F_GETLK64", "F_SETLK64" and "F_SETLKW64" should be ignored.

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

Fix: Implement RING_BUFFER_GET_NEXT_SUBBUF_METADATA_CHECK

Get next metadata subbuffer, returning a flag indicating whether the
metadata is guaranteed to be in a consistent state at the end of this
sub-buffer (can be parsed).

This can be used by the consumer to know whether the metadata can be
parsed at the end of this sub-buffer, which is useful to distinguish
between errors and incomplete metadata in live tracing.

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

fix: vmalloc_sync_mappings was backported to v5.5.12

Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Ie554d9c956afc2a8e114fe41e4b3c225d8af40a1

Update: Additional kernel ranges for vmalloc_sync_mappings

Some Ubuntu kernels cannot be directly mapped to an upstream stable
version. Define distro specific ranges for those (4.15, 5.0, 5.3).

Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Update: Use vmalloc_sync_mappings for stable kernels

Starting from v5.4.28/v5.2.37/v4.19.113/v4.14.175/v4.9.218/v4.4.218, stable
kernel branches backported v5.6 upstream commit [1], causing the following
warnings:
...
[  483.242037] LTTng: vmalloc_sync_all symbol lookup failed.
[  483.257056] Page fault handler and NMI tracing might trigger faults.
...

Extend check for vmalloc_sync_mappings for stable kernels as well.

[1] https://github.com/torvalds/linux/commit/763802b53a427ed3cbd419dbba255c414fdd9e7c

[ Edit: minor coding style fix by Mathieu Desnoyers. ]

Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: Use vmalloc_sync_mappings on kernel 5.6 as well

Upstream commit [1], that got rid of vmalloc_sync_all and introduced
vmalloc_sync_mappings, is a v5.6 commit:
$ git tag --contains 763802b53a427ed3cbd419dbba255c414fdd9e7c
v5.6
v5.6-rc7
v5.7-rc1
v5.7-rc2
v5.7-rc3

Extend the LINUX_VERSION_CODE check to v5.6 to fix the following warnings:
...
[  483.242037] LTTng: vmalloc_sync_all symbol lookup failed.
[  483.257056] Page fault handler and NMI tracing might trigger faults.
...

[1] https://github.com/torvalds/linux/commit/763802b53a427ed3cbd419dbba255c414fdd9e7c

Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Cleanup: remove unsupported `ctf_float()` macros

Tracing floats is not supported for the kernel tracer. Disallow building
kernel probes with those fields, rather than silently ignoring them.

Signed-off-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I1cf9751df96d2af3b54f725797bd20d7b05f2b38

Cleanup: have interpreter functions return _DISCARD instead of 0

It's easier to understand the meaning of the zero return value of these
function using the enum. It makes it obvious.

Signed-off-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I1df8f704fa9f6768f413c12c3c1de61a94b3aff8

Cleanup: bytecode: typo: "s16" -> "u16"

Signed-off-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I68901ca2d89d08f2cb69853816e0214c588aa7f8

Cleanup: Rename patches.i to patches.h

This generated header file contains a list of patches applied on the
lttng-modules tree. Based on the C99 specification, ".i" files are not
supposed to be preprocessed, although this header header file is
expected to be preprocessed.

Rename it from ".i" to ".h" to convey that it is a C header meant to be
preprocessed.

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

Cleanup: Move all source files to src/

This includes *.c, lib/*/*.c, probes/*.c, wrapper/*.c.

Adapt Makefile and Kbuild accordingly. Introduce src/Kbuild.

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

Cleanup: Move patches.i to include/generated/

Move patches.i from /extra_version to include/generated/ so we
can include them without using relative path includes.

Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I87927a372ffeb244f3c097c9bb80eeca7d9f99eb

Cleanup: Move lttng-modules instrumentation headers

The directory hierarchy "instrumentation/events/lttng-module/" only
exists for historical reasons and is not needed anymore. Move all
its contents into "instrumentation/events/".

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

Cleanup: Remove toplevel directory from include search path

Now that all include files are moved to include/ (except for those
meant to be included with "#include "...h"), we can remove the toplevel
directory from the include search path.

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

Cleanup: Move blacklist/ headers to include/blacklist/

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

Cleanup: Move wrapper/ headers to include/wrapper/

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

Cleanup: Move instrumentation/ headers to include/instrumentation/

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

Cleanup: Remove deprecated TODO file

All relevant items that were left were moved to
https://bugs.lttng.org/projects/lttng-modules "Feature".

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

fix: add missing guid_t type to wrapper

Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I0de39c24a7925b580fabbdaa12dbe05c43cfcd98

Fix: missing wrapper rename to wrapper_vmalloc_sync_mappings

Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Idf7082a980c5a604bfef5c69906678b5083a9bbf

Cleanup: Move headers from toplevel to include/lttng/

- Remove extra "lttng-" from filename (now implied by the path).
- Adapt includes accordingly.

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

Cleanup: Move headers from probes/ to include/lttng/

- Remove extra "lttng-" from filename (now implied by the path).
- Adapt includes accordingly.
- Adapt lttng-syscalls-generate-headers.sh header generation script
  accordingly.
- Remove probes/lttng.h, include its PARAMS() define in the two
  user headers.

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

Cleanup: Move headers from lib/ to include/lttng/

Adapt includes accordingly.

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

Cleanup: Move lib/ringbuffer/ headers to include/ringbuffer/

Remove the <wrapper/ringbuffer/...> proxy include files, and add the
include/ directory to the preprocessor include search patch.

Adapt all includes accordingly.

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

Fix: wrapper random documentation

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

Update for kernel 5.7: use vmalloc_sync_mappings on kernels >= 5.7

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

Unbreak LTTng for kernel 5.7

Linux commit 0bd476e6c67190b5eb7b6e105c8db8ff61103281 ("kallsyms:
unexport kallsyms_lookup_name() and kallsyms_on_each_symbol()") breaks
LTTng-modules by removing symbols used by the LTTng-modules out-of-tree
tracer.

I pointed this out when the change was originally considered before the
5.7 merge window. This generated some discussion but it did not lead to
any concrete proposal to fix the issue. [1]

The commit has been merged in the 5.7 merge window. At that point, as
maintainer of LTTng, I immediately raised a flag about this issue,
proposing an alternative approach to solve this: expose the few symbols
needed by LTTng to GPL modules. This was NACKed on the ground that the
Linux kernel cannot export GPL symbols when there are no in-tree
users. [2]

Steven Rostedt has shown interest in merging LTTng-modules upstream.
LTTng-modules being LGPL, this is very much doable. I have prepared a
tree of LTTng-modules "for upstreaming" and sent it to him privately so
he can review it. Even if in an ideal scenario LTTng-modules is merged
for the following merge window, it leaves LTTng-modules broken on the
5.7 kernel.

In order to ensure that the LTTng-modules kernel tracer continues working
for my end users on kernels 5.7 onwards, as a very last resort, this is
with great reluctance that I created this fix for LTTng modules. It
basically uses kprobes to lookup the kallsyms_lookup_name symbol, and
continues using kallsyms_lookup_name as before.

Link: https://lore.kernel.org/r/20200302192811.n6o5645rsib44vco@localhost
Link: https://lore.kernel.org/r/20200409193543.18115-1-mathieu.desnoyers@efficios.com
Link: https://lwn.net/Articles/817988/
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Will Deacon <will@kernel.org>
CC: akpm@linux-foundation.org
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC: Masami Hiramatsu <mhiramat@kernel.org>
CC: rostedt@goodmis.org
CC: Alexei Starovoitov <ast@kernel.org>

Move lttng wrappers into own module

Currently, we only pull the wrapper symbols into a single sub-module,
either:

lttng-tracer.o:
  - wrapper/random.o
  - wrapper/trace-clock.o
  - wrapper/page_alloc.o

or

lttng-statedump.o:
  - wrapper/irqdesc.o
  - wrapper/fdtable.o

Because lttng-tracer depends on lttng-statedump, we cannot just put all
wrappers into lttng-tracer.o, because it would create a circular
dependency. This will be an issue if we introduce common wrappers which
are used in both lttng-tracer.o and in lttng-statedump.o.

Introduce a new lttng-wrapper.o to contain all wrapper symbols for all
lttng modules.

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

Introduce lttng_guid_gen wrapper for kernels >= 5.7.0

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

instrumentation: update x86 kvm instrumentation for kernel >= 5.7.0

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

instrumentation: update mm_vmscan for kernel >= 5.7.0

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

filter: bytecode already in the list should go before

Background
==========
This `seqnum` (sequence number) feature is currently unused. It was
designed so that the session daemon could tell the tracer the order in
which the bytecode should be run.

Issue
=====
The current implementation of the session daemon doesn't use this
feature so there is only ever a single bytecode to execute per callsite.

During work on an upcoming feature uses this `seqnum` became useful and
it was realized that the current bytecode linking code would reverse the
order in which the bytecode were executed when all bytecodes have the
same `seqnum` value.

This is due to the fact that the `cds_list_for_each_entry_reverse` loops
until it finds a `seqnum` smaller than the new one.

So if all bytecodes have the same `seqnum`, the new bytecode will be
added at the beginning of the list.

This is not technically a problem since it's the session daemon's job to
set the sequence number if it wants a particular ordering. Even
considering that, we found it counterintuitive that new bytecodes are
added at the beginning of the list in those cases.

Solution
========
This commit makes it so that on equality, the insertion is done after
the existing bytecodes.

Signed-off-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I784887e3e6085f9344a2bb429d4f0d30586ebc57

tracepoint: Refactor representation of nested types

Refactor enumeration, sequence, array, structure, and variant types.

Implement internal data structures to support nested types.

All probe providers using ctf_enum(), ctf_array*() and ctf_sequence*()
are switched to this new internal type representation.

Each of sequence, array, struct and variant gain a "alignment" property,
which is a feature which was needed in lttng-modules to express
alignment for an array or sequence of bits.

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

wrapper/compiler.h: Implement __LTTNG_COMPOUND_LITERAL

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

Update to SPDX v3.0 identifiers

The short form of GPL-2.0 and LGPL-2.1 were deprecated in favour of the
clearer GPL-2.0-only and GPL-2.0-or-later in the SPDX license list v3.0.

Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: If2337f5c67a2548d7f25043e67006211213cbe3e

fix: uaccess wrapper for CentOS >= 4.18.0-147

Fixes: #1253
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I2a79c1c0e897a6148e60e5599949cd2778d09d50

fix: ext4 instrumentation for CentOS >= 4.18.0-147

Fixes: #1253
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I1fd54af16fbb02cd4b3ab7fc7d9232708088f1fd

fix: signal instrumentation for CentOS >= 4.18.0-147

Fixes: #1253
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I280013402df6f14222fbb912cdf64d80af3ab265

fix: kvm instrumentation for CentOS >= 4.18.0-147

Fixes: #1253
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Ide20ebf51bec503866ffc96dda3e0b09ebeb14d6

fix: rcu instrumentation for CentOS >= 4.18.0-80

Fixes: #1253
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I1735d2caa7215ce94272aaaa98cbbc8f3a10743d

Fix: update kvm instrumentation for Ubuntu 5.3.0-45

This commit introduced in 5.3.0-43 was dropped in 5.3.0-45 and reintroduced
in 5.3.0-46:

  commit 795f8a34f279e17c279bba46da10f15c5dd00264
  Author: Sean Christopherson <sean.j.christopherson@intel.com>
  Date:   Fri Dec 6 15:57:14 2019 -0800

    KVM: x86: Use gpa_t for cr2/gpa to fix TDP support on 32-bit KVM

BugLink: https://bugs.launchpad.net/bugs/1867051
    [ Upstream commit 736c291c9f36b07f8889c61764c28edce20e715d ]

Fun times!

Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Ia5f1a4ba355f592f09e964038b6334ddb3ad5153

Fix: update kvm instrumentation for Ubuntu 5.3.0-43

Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I1ce5f9ebba997fcc4cfbae6901eed479e2e1a79e

Fix: fcntl enum: only emit F_GETOWNER_UIDS for kernels >= 3.6

It appears in upstream Linux kernel
commit 1d151c337d79 "c/r: fcntl: add F_GETOWNER_UIDS option"
which was first released in v3.6.

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

syscalls: Make the cmd field of fcntl an enum

The fcntl system call has a cmd parameter which is one of multiple
values defined in the linux/fcntl.h file. This field is now an
enumeration of the various possible values.

Here's an example babeltrace output of the fcntl system call:

[...] syscall_entry_fcntl: { cpu_id = 3 }, { fd = 35,
cmd = ( "F_GETFL" : container = 3 ), arg = 140388746332169 }

Change-Id: I06f511d5dba986aaf01b50057cbe6eac789bbea7
Signed-off-by: Geneviève Bastien <gbastien+lttng@versatic.net>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

syscalls: Make the flags and mode fields of open[at] enumerations

The open and openat system call have a flags and mode fields, whose values
are defined in the linux/fcntl.h file. These fields are now
enumerations that can be read as a bit field enum, to make the values more
readable / meaningful.

Here's an example babeltrace output of the open system call:

[...] syscall_entry_openat: { cpu_id = 0 }, { dfd = -100,
filename = "/tmp/edg0_383407",
flags = ( "O_RDWR" | "O_CREAT" | "O_TRUNC" : container = 578 ),
mode = ( "S_IWOTH" | "S_IROTH" | "S_IWGRP" | "S_IRGRP" |
   "S_IWUSR" | "S_IRUSR" : container = 438 ) }

Change-Id: Id7a516670b03e52fc75f9ff3c6ba8114c61a3865
Signed-off-by: Geneviève Bastien <gbastien@versatic.net>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: update kvm instrumentation for Ubuntu 4.15.0-92

Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Ib367b9a0ce3846f45313906e710a9a6d644e3955

Record event as soon as one filter evaluates to TRUE

This is a tiny optimization but it can reduce tracing cost in cases
where multiple filters are attached to a probe.

Since we want to trace an event if any of its filter expressions
evaluates to TRUE, there is no need to keep on evaluating expressions
once one is found to be TRUE.

Signed-off-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I6b5b7697869d3e25dc24d38dc39c34ae1d49dcc9

Add UDP and ICMP packet header information to the tracepoint

* UDP transport header
* ICMP transport header

Signed-off-by: Florian Walbroel <walbroel@silexica.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

statedump: introduce file_table_address

Currently the LTTng-modules statedump simply iterates over all processes
in the system and assumes all threads share the same file descriptor
table, which is only true if threads were created with clone
CLONE_FILES.

Directly invoking clone without the CLONE_FILES creates threads which
belong to the same process, but have their own file descriptor table.

Therefore, model-wise, we cannot assume that all threads in a process
have the same fd table content.

Add a new "file_table_address" field to the lttng_statedump_process_state
event, which dumps the address of the thread's struct files_struct
pointer. This pointer is guaranteed to never be re-used while we hold
the RCU read-side lock (so for the entire iteration over
processes/threads).

For the lttng_statedump_file_descriptor event, remove the "pid" field
(which is semantically inaccurate) and add a "file_table_address" field,
which contains the struct files_struct address of the file table
containing the file descriptor.

An optimization is performed to eliminate most duplcated file table
content by skipping file table dump if the same file table address is
encountered consecutively while iterating over a process' threads.

This introduces a semantic change to the statedump fields, and will
therefore be introduced in lttng-modules 2.12 onwards, not backported as
a fix.

Fixes: #1245
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Remove kernel version from syscall headers name

This will reduce the delta when updating the syscall headers and make it
easier to track the changes.

Add a comment in the headers to track the version they were generated
from.

Change-Id: I939e1ebd8ab18d880ff1394e771982b5491d3b19
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Add script to automate the syscall extraction process

Change-Id: Ic8e1e62058616f221569e1f5ed2ffb9d54275af5
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Update lttng-syscalls-extractor for v5.6.0

Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I48e4d82484d6edcc7601a40d2f94e5c46ad5184b

Add a Makefile for the lttng-syscalls-extractor module

Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I0c1cc650d8594ef01b4039bb3d2af94bfddea54d

Cleanup: Syscall headers scripts shellcheck warnings

Change-Id: Ia616724d942f43f5fde2186bff28446120b17c43
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Remove lttng-ftrace integration

The lttng-ftrace integration (LTTNG_KERNEL_FUNCTION instrumentation
type) was unused for a while now. The "function" probing is actually
done with kprobes and kretprobes (LTTNG_KERNEL_KPROBE and
LTTNG_KERNEL_KRETPROBE).

Remove it so a use of kallsyms_lookup_name() can be removed as well.
Note that in the future we could add back this support by using
register_ftrace_function() which is exported to kernel modules, but
considering that we have not been using this code for a while,
just remove the implementation for now.

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

Remove dependency on kallsyms for splice_to_pipe (kernel 4.2+)

Upstream commit 2b514574f7e88 "net: af_unix: implement splice for stream
af_unix sockets" exported the "splice_to_pipe" symbol, so use it to
remove a dependency on kallsyms_lookup_name().

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

Remove dependency on kallsyms for irq_to_desc (kernel 3.4+)

Upstream commit 3911ff30f5d "genirq: export handle_edge_irq() and
irq_to_desc()" exported the irq_to_desc symbol, so use it to remove a
dependency on kallsyms_lookup_name().

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

Remove work-around for signed tracepoint module tainting (kernel 3.15+)

Upstream commit 66cc69e34e86a "Fix: module signature vs tracepoints: add
new TAINT_UNSIGNED_MODULE" fixed an issue where the kernel was
considering unsigned modules as tainting the kernel in the same way as a
force-loaded modules, which was causing the tracepoints within those
modules to be hidden.

This fix was merged in kernel 3.15, so there is no use in applying this
work-around starting from that kernel.

This removes a dependency on kallsyms_lookup_name() for the symbol
"tracepoint_module_notify".

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

Change integer base to hex for fields representing addresses

It seems more expected to show addresses in hexadecimal.

I applied this to all fields named "ip" or "addr".

I haven't change the `addr` fields in the i2c.h file as I am not aware
of what is the convention when displaying I2C addresses.

Signed-off-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I6ed00b31e319e1d966ab138471248dcf3d2c7315

Fix: rcu: Fix data-race due to atomic_t copy-by-value (5.5.6, 5.4.22)

The following upstream commit has been backported to stable kernels
5.5.6 and 5.4.22:

  commit 6cf539a87a61a4fbc43f625267dbcbcf283872ed
  Author: Marco Elver <elver@google.com>
  Date:   Wed Oct 9 17:57:43 2019 +0200

    rcu: Fix data-race due to atomic_t copy-by-value

    This fixes a data-race where `atomic_t dynticks` is copied by value. The
    copy is performed non-atomically, resulting in a data-race if `dynticks`
    is updated concurrently.

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

fix: y2038: hide timeval/timespec/itimerval/itimerspec types (v5.6)

See upstream commit:

  commit c766d1472c70d25ad475cf56042af1652e792b23
  Author: Arnd Bergmann <arnd@arndb.de>
  Date:   Thu Feb 20 20:03:57 2020 -0800

    y2038: hide timeval/timespec/itimerval/itimerspec types

    There are no in-kernel users remaining, but there may still be users that
    include linux/time.h instead of sys/time.h from user space, so leave the
    types available to user space while hiding them from kernel space.

    Only the __kernel_old_* versions of these types remain now.

Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I986a813ad8b1c753ab1fa07f726b0cc481f049cb

fix: use timespec64 on kernels that have it

This fixes v5.6 which has hidden 'struct timespec' from kernel code and
makes 32bit archs y2038 compliant on v3.17 and newer.

Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I1daedc4a93cbbebb8f5a1d99c4619cb27f6a9e07

fix: move lttng_close_on_exec to proper wrapper

Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I330c6d63fc9c1af00c9a9471563d322d036b9a9c

fix: 'struct timex' removed upstream (v5.6)

The 'timex' struct was remove in v5.6 and replaced by 2 variants, one
that is y2038 compliant and a compat version for 32bit archs.

Add this temporary fix while we update our syscalls tracepoint headers,
the type of this struct has limited importance since it's only used to
record the adress in the trace.

Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Change-Id: I085b22f282db57985f1c3d341e7c0866cb20e3c9

Fix: statedump: consistently check task_cred_xxx() return value for NULL

trace_lttng_statedump_process_user_ns() internally checks whether
user_ns is NULL. While this does not appear to be a possible return
value for task_cred_xxx(), err on the safe side and check for NULL here
as well to be consistent with the paranoid behavior of
trace_lttng_statedump_process_user_ns().

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

Fix: statedump: check task_active_pid_ns return value for NULL

The lttng-statedump checks the return value of task_active_pid_ns()
before each use within lttng_statedump_process_pid_ns(), but misses
the NULL check before dereferencing pid_ns->parent.

This race happens if a task exists in "dead" state while the statedump
iterates on that task.

Reported-by: Li Zhou <li.zhou@windriver.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: lttng-events.c: variable may be used uninitialized

Fixes the following warning:
/home/frdeso/projets/lttng/modules/lttng-events.c: In function ‘print_metadata_escaped_field’:
/home/frdeso/projets/lttng/modules/lttng-events.c:2563:5: error: ‘ret’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
     if (ret)
           ^

Signed-off-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: If2db5e1ad9782fb49d6d07026976d3d22f89f2ab

Cleanup: remove trailing white spaces across project

Signed-off-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I2de34e4913f9cefbd72a138f2d3dfb9d67ece311

sched: Make the sched_switch task state an enum

This gives meaning to the task state value. Only the bit masks are
enumerated, as defined compositions are not exhaustive listing of all
possible values and there would be a lot of unknown. Interpretation of
combination of bit flags is left to the consumer of the event.

Change-Id: I83c5fbee9cba2701c7238c0ac6abd4c8a351b193
Signed-off-by: Geneviève Bastien <gbastien@versatic.net>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

block: Make the rwbs field as a bit field enum

The rwbs value of block request events is in fact a series of bit fields
set to 0 or 1. The enumeration values are all powers of 2, trace readers
could interpret this as a bit field enum and show the result as a
concatenation of the corresponding flags. For example, with a matching
patch for babeltrace2's pretty sink, the output for a rwbs value of 12
would be:

[13:15:49.024354958] (+0.000003868) wilbrod block_rq_complete: { cpu_id = 4 },
    { dev = 8388624, sector = 375490176, nr_sector = 360, error = 0,
      rwbs = ( "RWBS_FLAG_READ" | "RWBS_FLAG_RAHEAD" : container = 12 ) }

Consumers who have no notion of the bit field enum can still use the
integer value of the field as before.

Change-Id: I2e873f16e5a0507e52cfc85c70b471a9f4d5d5d1
Signed-off-by: Geneviève Bastien <gbastien@versatic.net>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

fix: workqueue: add worker function to workqueue_execute_end tracepoint (v5.6)

See upstream commit :

  commit 1c5da0ec7f20dfb56030fb93f7f52f48e12deb52
  Author: Daniel Jordan <daniel.m.jordan@oracle.com>
  Date:   Mon Jan 13 17:52:39 2020 -0500

    workqueue: add worker function to workqueue_execute_end tracepoint

    It's surprising that workqueue_execute_end includes only the work when
    its counterpart workqueue_execute_start has both the work and the worker
    function.

    You can't set a tracing filter or trigger based on the function, and
    postprocessing scripts interested in specific functions are harder to
    write since they have to remember the work from _start and match it up
    with the same field in _end.

    Add the function name, taking care to use the copy stashed in the
    worker since the work is no longer safe to touch.

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

fix: media: v4l2: abstract timeval handling in v4l2_buffer (v5.6)

See upstream commit :

  commit 77cdffcb0bfb87fe3645894335cb8cb94917e6ac
  Author: Arnd Bergmann <arnd@arndb.de>
  Date:   Mon Dec 16 15:15:00 2019 +0100

    media: v4l2: abstract timeval handling in v4l2_buffer

    As a preparation for adding 64-bit time_t support in the uapi,
    change the drivers to no longer care about the format of the
    timestamp field in struct v4l2_buffer.

    The v4l2_timeval_to_ns() function is no longer needed in the
    kernel after this, but there is userspace code relying on
    it to be part of the uapi header.

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

fix: rcu: Remove kfree_rcu() special casing and lazy-callback (v5.6)

See upstream commit :

  commit 77a40f97030b27b3fc1640a3ed203870f0817f57
  Author: Joel Fernandes (Google) <joel@joelfernandes.org>
  Date:   Fri Aug 30 12:36:32 2019 -0400

    rcu: Remove kfree_rcu() special casing and lazy-callback handling

    This commit removes kfree_rcu() special-casing and the lazy-callback
    handling from Tree RCU.  It moves some of this special casing to Tiny RCU,
    the removal of which will be the subject of later commits.

    This results in a nice negative delta.

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

fix: rcu: Fix data-race due to atomic_t copy-by-value (v5.6)

See upstream commit :

  commit 6cf539a87a61a4fbc43f625267dbcbcf283872ed
  Author: Marco Elver <elver@google.com>
  Date:   Wed Oct 9 17:57:43 2019 +0200

    rcu: Fix data-race due to atomic_t copy-by-value

    This fixes a data-race where `atomic_t dynticks` is copied by value. The
    copy is performed non-atomically, resulting in a data-race if `dynticks`
    is updated concurrently.

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

fix: btrfs: make btrfs_ordered_extent naming consistent (v5.6)

See upstream commit :

  commit bffe633e00fb6b904817137fc17a44b42efcd985
  Author: Omar Sandoval <osandov@fb.com>
  Date:   Mon Dec 2 17:34:19 2019 -0800

    btrfs: make btrfs_ordered_extent naming consistent with btrfs_file_extent_item

    ordered->start, ordered->len, and ordered->disk_len correspond to
    fi->disk_bytenr, fi->num_bytes, and fi->disk_num_bytes, respectively.
    It's confusing to translate between the two naming schemes. Since a
    btrfs_ordered_extent is basically a pending btrfs_file_extent_item,
    let's make the former use the naming from the latter.

    Note that I didn't touch the names in tracepoints just in case there are
    scripts depending on the current naming.

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

fix: KVM: x86: Use gpa_t for cr2/gpa to fix TDP support on 32-bit (v5.6)

See upstream commit :

  commit 736c291c9f36b07f8889c61764c28edce20e715d
  Author: Sean Christopherson <sean.j.christopherson@intel.com>
  Date:   Fri Dec 6 15:57:14 2019 -0800

    KVM: x86: Use gpa_t for cr2/gpa to fix TDP support on 32-bit KVM

    Convert a plethora of parameters and variables in the MMU and page fault
    flows from type gva_t to gpa_t to properly handle TDP on 32-bit KVM.

    Thanks to PSE and PAE paging, 32-bit kernels can access 64-bit physical
    addresses.  When TDP is enabled, the fault address is a guest physical
    address and thus can be a 64-bit value, even when both KVM and its guest
    are using 32-bit virtual addressing, e.g. VMX's VMCS.GUEST_PHYSICAL is a
    64-bit field, not a natural width field.

    Using a gva_t for the fault address means KVM will incorrectly drop the
    upper 32-bits of the GPA.  Ditto for gva_to_gpa() when it is used to
    translate L2 GPAs to L1 GPAs.

    Opportunistically rename variables and parameters to better reflect the
    dual address modes, e.g. use "cr2_or_gpa" for fault addresses and plain
    "addr" instead of "vaddr" when the address may be either a GVA or an L2
    GPA.  Similarly, use "gpa" in the nonpaging_page_fault() flows to avoid
    a confusing "gpa_t gva" declaration; this also sets the stage for a
    future patch to combing nonpaging_page_fault() and tdp_page_fault() with
    minimal churn.

    Sprinkle in a few comments to document flows where an address is known
    to be a GVA and thus can be safely truncated to a 32-bit value.  Add
    WARNs in kvm_handle_page_fault() and FNAME(gva_to_gpa_nested)() to help
    document such cases and detect bugs.

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

fix: proc: decouple proc from VFS with "struct proc_ops" (v5.6)

See upstream commit :

  commit d56c0d45f0e27f814e87a1676b6bdccccbc252e9
  Author: Alexey Dobriyan <adobriyan@gmail.com>
  Date:   Mon Feb 3 17:37:14 2020 -0800

    proc: decouple proc from VFS with "struct proc_ops"

    Currently core /proc code uses "struct file_operations" for custom hooks,
    however, VFS doesn't directly call them.  Every time VFS expands
    file_operations hook set, /proc code bloats for no reason.

    Introduce "struct proc_ops" which contains only those hooks which /proc
    allows to call into (open, release, read, write, ioctl, mmap, poll).  It
    doesn't contain module pointer as well.

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

Version 2.12.0-rc1

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

Fix: lttng-syscalls.c: marking wrong syscall probe as unregistered

When calling `lttng_syscalls_unregister()` we currently mark as
unregistered the wrong syscall probe type.

Concretely, when we unregister "sys_exit" we wrongfully mark that
sys_enter is unregistered and vice versa.

Given than currently entry and exit probes are always enabled together
(except on internal errors), the effect of this bug is not user-visible.

Signed-off-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I64acf6a941a3d1fa1bf8be424f834ddb7fb92ace

Version 2.12.0-pre

Integrate the missing 2.11.0-rc1 entries to the changelog. This
was caused by forking to stable-2.11 the commit before the v2.11.0-rc1
tag. In the future, we will try to keep the rc1 tag as the common
ancestor between master and stable branches.

This also updates the lttng-modules version to 2.12.0-pre, which is
a state that will stay until the v2.12.0-rc1 tag.

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

Bump LTTNG_MODULES_ABI_MINOR_VERSION to 5

New operations were added to the lttng-modules ABI as part of the 2.12
release cycle to support UID tracking and the "session clear"
functionality.

This will allow future LTTng-tools versions to check for those
capabilities.

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

fix: use user ns wrapper code in new id trackers

These wrappers are required to translate kuid on kernels prior to v3.5.

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

fix: function prototype in wrapper/mm.h

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

ID tracker: implement vpid/uid/vuid/gid/vgid trackers

Co-developed-by: Jonathan Rajotte <jonathan.rajotte-julien@efficios.com>
Signed-off-by: Jonathan Rajotte <jonathan.rajotte-julien@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

lttng-abi: Document ioctl numbers reserved by lttng-abi-old.h

Document the ioctl numbers reserved by lttng-abi-old.h in the
(relatively) new lttng-abi.h, so they are taken into account when
assining numbers to new lttng ioctl commands.

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

lttng-clear: stop tracing required

Require that tracing is stopped when buffers are cleared. Update
comments and warning checks to that effect.

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

sunrpc: introduce lttng_get_clid helper

Introduce the lttng_get_clid helper to always check for NULL pointer
when getting the client id. While not always strictly needed depending
on the tracepoint callsite, prefer robustness of instrumentation and
always check for NULL rather than play whack-a-mole.

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

Fix: sunrpc: use signed integer for client id

Within include/linux/sunrpc/clnt.h:struct rpc_cltn, the cl_clid field
is an unsigned integer, which is the type expected by the tracepoint
signature.

However, looking into net/sunrpc/clnt.c:rpc_alloc_clid(), its allocation
considers negative signed integer as errors.

Therefore, in order to properly show "-1" in the trace output (rather
than MAX_INT) when called with a NULL task->tk_client, move to a
signed integer as backing type for the client_id field.

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

Fix: sunrpc: null rpc_clnt dereference in rpc_task_queued tracepoint

Based on upstream Linux commit:

commit 0be283f676a1e7b208db0c992283197ef8b52158
Author: Benjamin Coddington <bcodding@redhat.com>
Date:   Tue Jan 23 09:32:35 2018 -0500

    SUNRPC: Fix null rpc_clnt dereference in rpc_task_queued tracepoint

    Backchannel tasks will not have a reference to the rpc_clnt.  Return -1 for
    cl_clid in that case.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trondmy@gmail.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: SUNRPC: Fix oops when trace sunrpc_task events in nfs client

See upstream commit :

commit 2ca310fc4160ed0420da65534a21ae77b24326a8
Author: Ditang Chen <chendt.fnst@cn.fujitsu.com>
Date: Fri, 7 Mar 2014 13:27:57 +0800
Subject: SUNRPC: Fix oops when trace sunrpc_task events in nfs client

When tracking sunrpc_task events in nfs client, the clnt pointer may be NULL.

[  139.269266] BUG: unable to handle kernel NULL pointer dereference at 0000000000000004
[  139.269915] IP: [<ffffffffa026f216>] ftrace_raw_event_rpc_task_running+0x86/0xf0 [sunrpc]
[  139.269915] PGD 1d293067 PUD 1d294067 PMD 0
[  139.269915] Oops: 0000 [#1] SMP
[  139.269915] Modules linked in: nfsv4 dns_resolver nfs lockd sunrpc fscache sg ppdev e1000
serio_raw pcspkr parport_pc parport i2c_piix4 i2c_core microcode xfs libcrc32c sd_mod sr_mod
cdrom ata_generic crc_t10dif crct10dif_common pata_acpi ahci libahci ata_piix libata dm_mirror
dm_region_hash dm_log dm_mod
[  139.269915] CPU: 0 PID: 59 Comm: kworker/0:2 Not tainted 3.10.0-84.el7.x86_64 #1
[  139.269915] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[  139.269915] Workqueue: rpciod rpc_async_schedule [sunrpc]
[  139.269915] task: ffff88001b598000 ti: ffff88001b632000 task.ti: ffff88001b632000
[  139.269915] RIP: 0010:[<ffffffffa026f216>]  [<ffffffffa026f216>] ftrace_raw_event_rpc_task_running+0x86/0xf0 [sunrpc]
[  139.269915] RSP: 0018:ffff88001b633d70  EFLAGS: 00010206
[  139.269915] RAX: ffff88001dfc5338 RBX: ffff88001cc37a00 RCX: ffff88001dfc5334
[  139.269915] RDX: ffff88001dfc5338 RSI: 0000000000000000 RDI: ffff88001dfc533c
[  139.269915] RBP: ffff88001b633db0 R08: 000000000000002c R09: 000000000000000a
[  139.269915] R10: 0000000000062180 R11: 00000020759fb9dc R12: ffffffffa0292c20
[  139.269915] R13: ffff88001dfc5334 R14: 0000000000000000 R15: 0000000000000000
[  139.269915] FS:  0000000000000000(0000) GS:ffff88001fc00000(0000) knlGS:0000000000000000
[  139.269915] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  139.269915] CR2: 0000000000000004 CR3: 000000001d290000 CR4: 00000000000006f0
[  139.269915] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  139.269915] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[  139.269915] Stack:
[  139.269915]  000000001b633d98 0000000000000246 ffff88001df1dc00 ffff88001cc37a00
[  139.269915]  ffff88001bc35e60 0000000000000000 ffff88001ffa0a48 ffff88001bc35ee0
[  139.269915]  ffff88001b633e08 ffffffffa02704b5 0000000000010000 ffff88001cc37a70
[  139.269915] Call Trace:
[  139.269915]  [<ffffffffa02704b5>] __rpc_execute+0x1d5/0x400 [sunrpc]
[  139.269915]  [<ffffffffa0270706>] rpc_async_schedule+0x26/0x30 [sunrpc]
[  139.269915]  [<ffffffff8107867b>] process_one_work+0x17b/0x460
[  139.269915]  [<ffffffff8107942b>] worker_thread+0x11b/0x400
[  139.269915]  [<ffffffff81079310>] ? rescuer_thread+0x3e0/0x3e0
[  139.269915]  [<ffffffff8107fc80>] kthread+0xc0/0xd0
[  139.269915]  [<ffffffff8107fbc0>] ? kthread_create_on_node+0x110/0x110
[  139.269915]  [<ffffffff815d122c>] ret_from_fork+0x7c/0xb0
[  139.269915]  [<ffffffff8107fbc0>] ? kthread_create_on_node+0x110/0x110
[  139.269915] Code: 4c 8b 45 c8 48 8d 7d d0 89 4d c4 41 89 c9 b9 28 00 00 00 e8 9d b4 e9
e0 48 85 c0 49 89 c5 74 a2 48 89 c7 e8 9d 3f e9 e0 48 89 c2 <41> 8b 46 04 48 8b 7d d0 4c
89 e9 4c 89 e6 89 42 0c 0f b7 83 d4
[  139.269915] RIP  [<ffffffffa026f216>] ftrace_raw_event_rpc_task_running+0x86/0xf0 [sunrpc]
[  139.269915]  RSP <ffff88001b633d70>
[  139.269915] CR2: 0000000000000004
[  140.946406] ---[ end trace ba486328b98d7622 ]---

Signed-off-by: Quanyang Wang <quanyang.wang@windriver.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

fix: ext4: Reserve revoke credits for freed blocks (v5.5)

See upstream commit:

  commit 83448bdfb59731c2f54784ed3f4a93ff95be6e7e
  Author: Jan Kara <jack@suse.cz>
  Date:   Tue Nov 5 17:44:29 2019 +0100

    ext4: Reserve revoke credits for freed blocks

    So far we have reserved only relatively high fixed amount of revoke
    credits for each transaction. We over-reserved by large amount for most
    cases but when freeing large directories or files with data journalling,
    the fixed amount is not enough. In fact the worst case estimate is
    inconveniently large (maximum extent size) for freeing of one extent.

    We fix this by doing proper estimate of the amount of blocks that need
    to be revoked when removing blocks from the inode due to truncate or
    hole punching and otherwise reserve just a small amount of revoke
    credits for each transaction to accommodate freeing of xattrs block or
    so.

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

fix: btrfs: tracepoints: constify all pointers (v5.5)

See upstream commit:

  commit 1d2e7c7c3ed73cc510a4dc093df2a935092ff5ad
  Author: David Sterba <dsterba@suse.com>
  Date:   Thu Oct 17 13:28:57 2019 +0200

    btrfs: tracepoints: constify all pointers

    We don't modify the data passed to tracepoints, some of the declarations
    are already const, add it to the rest.

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

fix: btrfs block group struct refactor (v5.5)

See upstream commits:

  commit 32da5386d9a4fd5c1155cecf703df104d918954c
  Author: David Sterba <dsterba@suse.com>
  Date:   Tue Oct 29 19:20:18 2019 +0100

    btrfs: rename btrfs_block_group_cache

    The type name is misleading, a single entry is named 'cache' while this
    normally means a collection of objects. Rename that everywhere. Also the
    identifier was quite long, making function prototypes harder to format.

  commit b3470b5dbe1300dea94191ae4b7d070be9a5cdc9
  Author: David Sterba <dsterba@suse.com>
  Date:   Wed Oct 23 18:48:22 2019 +0200

    btrfs: add dedicated members for start and length of a block group

    The on-disk format of block group item makes use of the key that stores
    the offset and length. This is further used in the code, although this
    makes thing harder to understand. The key is also packed so the
    offset/length is not properly aligned as u64.

    Add start (key.objectid) and length (key.offset) members to block group
    and remove the embedded key.  When the item is searched or written, a
    local variable for key is used.

  commit bf38be65f3703d5ef3661c0a2802bc28e76b8f19
  Author: David Sterba <dsterba@suse.com>
  Date:   Wed Oct 23 18:48:11 2019 +0200

    btrfs: move block_group_item::used to block group

    For unknown reasons, the member 'used' in the block group struct is
    stored in the b-tree item and accessed everywhere using the special
    accessor helper. Let's unify it and make it a regular member and only
    update the item before writing it to the tree.

    The item is still being used for flags and chunk_objectid, there's some
    duplication until the item is removed in following patches.

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

fix: y2038: itimer: change implementation to timespec64 (v5.5)

See upstream commit:

  commit bd40a175769d411b2a37e1c087082ac7ee2c15bb
  Author: Arnd Bergmann <arnd@arndb.de>
  Date:   Thu Nov 7 15:27:39 2019 +0100

    y2038: itimer: change implementation to timespec64

    There is no 64-bit version of getitimer/setitimer since that is not
    actually needed. However, the implementation is built around the
    deprecated 'struct timeval' type.

    Change the code to use timespec64 internally to reduce the dependencies
    on timeval and associated helper functions.

    Minor adjustments in the code are needed to make the native and compat
    version work the same way, and to keep the range check working after
    the conversion.

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

Update .gitignore from upstream

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

Add missing include for kernels between 3.8 and 3.15

This is required at least for:
 v3.13.x
 v3.11.x
 v3.9.x
 v3.8.x

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

Fix: LTTNG_KERNEL_ADD_CALLSITE: Handle unknown event type

Return -ENOSYS for unknown event type (similarly to other commands)
rather than falling-through the switch statement.

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

net: Add entry/exit tracepoints for all receive paths

In the linux kernel, there are entry and exit tracepoints on
the various paths of network reception.

Those tracepoints are useful to bound the network reception such that
all events happening between the entry and exit can be linked to this
network reception (for example, wakeups). They can also be used to
perform network stack latency analysis.

Acked-by: Julien Desfossez <jdesfossez@digitalocean.com>
Signed-off-by: Geneviève Bastien <gbastien@versatic.net>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

statedump: Add thread ID (tid) to interrupt

Threaded IRQs have a 'thread' field set in the the action structure,
defining which process to wakeup when the IRQ happens.

Having this information will allow to know which process are IRQ
handling process and the analyses can track what happens in those
processes to the IRQ that caused them to wake up.

[ Edit by Mathieu Desnoyers: Rename "thread" field to "tid" to stay
  consistent with the rest of lttng-modules tracepoints. ]

Signed-off-by: Geneviève Bastien <gbastien+lttng@versatic.net>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>