Introduce event counter extensible ABI structure layout

Introduce event counter ioctl argument structure with extensible layout
for new ioctls.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I120e057d136951973b9af801fd4940fb9866ce94

ABI refactoring: Rename event counter ABI to "old"

The counter ioctls exposed in 2.13 for notifications use a fixed-size
array for the number of dimensions.

We aim to replace this by variable length arrays in 2.14 for event
counters, and introduce new ABIs as extensible structures.

Rename the ioctls as follows:

- LTTNG_KERNEL_ABI_COUNTER -> LTTNG_KERNEL_ABI_OLD_COUNTER
- LTTNG_KERNEL_ABI_COUNTER_READ -> LTTNG_KERNEL_ABI_OLD_COUNTER_READ
- LTTNG_KERNEL_ABI_COUNTER_AGGREGATE -> LTTNG_KERNEL_ABI_OLD_COUNTER_AGGREGATE
- LTTNG_KERNEL_ABI_COUNTER_CLEAR -> LTTNG_KERNEL_ABI_OLD_COUNTER_CLEAR

And rename the following structures:

- lttng_kernel_abi_counter_dimension -> lttng_kernel_abi_old_counter_dimension
- lttng_kernel_abi_counter_conf -> lttng_kernel_abi_old_counter_conf
- lttng_kernel_abi_counter_index -> lttng_kernel_abi_old_counter_index
- lttng_kernel_abi_counter_value -> lttng_kernel_abi_old_counter_value
- lttng_kernel_abi_counter_read -> lttng_kernel_abi_old_counter_read
- lttng_kernel_abi_counter_aggregate -> lttng_kernel_abi_old_counter_aggregate
- lttng_kernel_abi_counter_clear -> lttng_kernel_abi_old_counter_clear

Introduce "TODO" comments where the new ABIs should be implemented.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I7a4f04e89a56ca1415d326976c4ea3afb9715295

kretprobe: Implement kretprobes with event enablers

This enables support for enabling only entry or exit for kretprobes.
This enables event notifier support for kretprobes.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Ieef4f2744d5e1ebfc2f3320862e143bfe6401620

kprobe: Implement kprobes with event enablers

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Idd1285baa8da6476620ddfc3c21d93a8d4ab08f7

ABI: introduce lttng_kernel_abi_match_check

Requires introduction of extended event parameters because there are
only 8 bytes of padding left in struct lttng_kernel_abi_event.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I3dd1346093eeee42c1a7a047ec32865fda9c6ff5

kretprobe: implement lttng_kretprobes_match_check

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I7a4584c3fa524664097a262d7b5f74eb93d2a335

kprobe: Introduce lttng_kprobes_match_check

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Iffc9dba158f9802db9f877fabeec288d5072a84c

Implement event notifier kretprobe support

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I32b42ddad79889a19ee8833ed9b52e4a37505f7b

Remove lttng_kernel_event_create warnings

Errors returned by lttng_kernel_event_create are handled by the caller,
and may happen e.g. when a kprobe or kretprobe symbol does not exist.
It should not generate a warning in the kernel console.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I0bd59ec35e5648fa6aa1ece3cf36714c5cc1a83e

kretprobes: implement event counter support

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Id5142ae8d31bba2c9a806f75cbbfefdca303d523

lttng_abi_create_event_notifier: add missing fallthrough

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I8e7011f63ccce4db21b36fcd18eb78e95ca2f406

Implement events-by-key hash table

Allow re-use of counter index for events with matching key.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Id1dff39ff3c58d5664d04ae5d77d1ae66e728cd6

Rename lttng_event_notifier_group events_ht to events_name_ht

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I64313d4b8255a717ef06ef7bf5944d2c1c4e24da

Rename lttng_get_event_ht_from_enabler to lttng_get_events_name_ht_from_enabler

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I53bb9917ae7644ba79f36dc16f9feb095a3c4194

Implement counter maps (for listing)

Also wire up LTTNG_KERNEL_ABI_SYSCALL_MASK in lttng_counter_ioctl.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: If9215bafb010162250636c9407d85fefcd61ebc2

Implement channel counter creation/destroy

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I2e242fe9b50f3b4ae5f97969b587f4306051109f

Cleanup: remove kprobes/kretprobes/uprobes unused exports

Can be removed now that those are embedded in the tracer core.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I14f4b011c562d7a2e669749159fda23ee964554f

Fix: circular dependency on symbol lttng_id_tracker_lookup

Adding lttng_id_tracker_lookup feature into kprobes, uprobes and
kretprobes introduces a circular dependency between lttng-tracer.ko and
the respective probe modules.

There is no real reason for having the kprobes/uprobes/kretprobes
modules separate from the tracer core, so combine those.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Iea80c8054054b341e1836c8675c04e00424608fc

Fix: circular dependency between lttng-events and lib counter

lib counter depends on lttng-events (tracer), not the opposite. Use the
lttng-counter clients callbacks to remove the circular dependency.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I04cdbfb39deb76884092459cab62227b9f39d85d

Implement event counter creation

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I5b407513c5c64ae418fc1846ae10f3fa99609796

Rename lttng_abi_create_event to lttng_abi_create_event_recorder_enabler

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I39b2e288b952e0316b6511f4f79014700cbc42e5

uprobe: implement counter support

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I46909ecc57a15d5f0c6b58e1f2f254219e55e01d

kretprobes: implement counter support

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I8e64712455b2812305250a45311b5b023281a1fe

kprobe: implement counter support

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I8741ab89b03089ec34f17965749f84ddc23a2601

Add missing counter handling

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I5ba6bc03b7c090e6c9b6431d81da4a739c764610

abi: introduce session common

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Id6512b87661d7e29666f41002370d065d540a27a

Implement event counter probe

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I6cdeef84a3b2f5675029a7509ce353a17bbeb0b4

Remove unused lttng_event_enabler_event_name_match_event

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Icd02b897aa6aaa870e503db873f86f80a04ff02c

Match event keys for syscall events

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Ia0b3df16abeda9e0a404eeed156e33c17f4f47e3

Skip sync of disabled enablers

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Icf20e16baee3c63b84f1be9f730100229108bcc6

Remove duplicate lookup in lttng_event_enabler_create_tracepoint_events_if_missing

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Ic597f34dfc3823ba83728bde3fcd41bb3eed9c91

Implement _lttng_kernel_event_create counter event support

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: If1a2e1d64d8663f592e81611914402d30f111e17

lttng_kernel_event_alloc: handler counters

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Ic50018274bd5048181f9da278027e1c175b6bd80

Refactor notification error counters

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I106b6fe85f899297582e131252c591ac5ba7d538

Add counter case in lttng_kernel_event_id_available

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I1967ddd37d677806558a41138f32566ce19bae21

Implement event counters

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I9eadee226c78c6b48158a0670b9b50a8b6aab06e

Add channel counter structures to internal header

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I00b2a4df48d66977deafedeb3e9f5021754bf42a

Wire up LTTNG_KERNEL_EVENT_TYPE_COUNTER

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Iddfaa8de487a376d35d404415bfec0676d7cb304

Refactor _lttng_event_destroy duplicated code

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I42a607101c084ade8ebed673b3a666987cfad98f

struct lttng_kernel_event_session_common_private: remove unused ctx field

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I99a8eb21db55ec8d9df2300853b3d08abec095e5

Rename struct lttng_kernel_session_private events_ht field to events_name_ht

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I2452d6154064fd91e801d0b8487168c7cdfb0a3e

Rename struct lttng_metadata_stream list field to node

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Iaefccfd27d18cbb90726f6b77400409eeea493d0

Rename struct lttng_kernel_session_private list field to node

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I971bb068e51567ef79a30608984137827f1d45c8

Reorder struct lttng_kernel_session_private fields

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I9a7c8f415c1b0b128662081f580df14bd5368893

Rename session events field to events_head

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I8181d86dc2dede4ba15178722e1eb884feb556eb

Rename session chan field to chan_head

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I4447978d05d2979e8c7e8c6d66126da66142e32c

Introduce struct lttng_event_counter_enabler

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I9683c18b4d661d65b128a1edda5adb1154d8d543

Introduce struct lttng_kernel_event_counter_private

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I2cc9d82a18f8222682e413e41a27acb8f8a74754

Move counter key structures to beginning of events-internal.h

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I4b76cac6837a5098720da9ae321169b46d78866b

Introduce struct lttng_kernel_channel_counter and struct lttng_kernel_channel_counter_ops

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Icdc8c1fb6444eca2051b60fa4a7dd564e943da68

Introduce struct lttng_kernel_event_counter

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Ie0e9ab234bce48c3ce23cf0d4c664ce4bb3bdaee

Introduce struct lttng_kernel_event_session_common_private

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Ibaab6a0a8ce60bbc5ac212106c5c75a8a16d7e2c

Introduce struct lttng_event_enabler_session_common

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Ia160e559525f9276512506271742703804be6c9b

Trace hit counters: introduce counter private data structures

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Ie6adadcbab8c41237b2bfb03b1c341b4183715cc

Trace hit counters: ABI

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I886975f27af90e42cbab274f70820a06090c48bc

Fix: libcounter: __lttng_counter_add global sum step alloc vs sync mixup

The global sum step needs to be handled on per-cpu allocated counters,
not per-cpu sync.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I9b6ef221fb099c9fc602dfdb9a93d70ae2192500

Fix: lttng_abi_validate_event_param: use kretprobe enum

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I8c444e16781fb8d8df9f05f0c70775f324ae030f

kvm instrumentation: Fix kvm_mmio event NULL pointer dereference

Upstream Linux commit e39d200fa5bf ("KVM: Fix stack-out-of-bounds read
in write_mmio") introduce a NULL pointer check within TP_fast_assign().

lttng-modules commit 33630522da97 ("Update kvm instrumentation for 4.15")
introduce use of:

  ctf_sequence_hex(unsigned char, val, val, u32, len)

without the required NULL pointer check, which can trigger NULL pointer
dereference in case of unsatisfied MMIO read.

Add the missing NULL pointer check. Record a sequence of length 0 in the
trace when the val pointer is NULL.

Reported-by: Fahad Arslan <fahad.arslan@siemens.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I51a171a56af96e2cf68dba73f7eb473dd6c0ba0e

kvm instrumentation: Cleanup: Eliminate code duplication

Commit 0badc02f82b38 ("Fix: adjust SLE version ranges to build with SP2
and SP3") introduced code duplication. Modify the version match logic to
remove duplicated code.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I918c87d2e6d68e6c71df18fbf66d88445ce68d23

Fix: Build on CentOS 9 Stream 2024-06

Change-Id: I445d2df9d49930e28e57b6a7d075a9f68e914bad
Signed-off-by: Kienan Stewart <kstewart@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

fix: file: Rename fcheck lookup_fd_rcu (v5.10.220)

See upstream backported commit:

  commit c4716bb296504cbc64aeefb370df44e821214c44
  Author: Eric W. Biederman <ebiederm@xmission.com>
  Date:   Fri Nov 20 17:14:27 2020 -0600

    file: Rename fcheck lookup_fd_rcu

    [ Upstream commit 460b4f812a9d473d4b39d87d37844f9fc30a9eb3 ]

    Also remove the confusing comment about checking if a fd exists.  I
    could not find one instance in the entire kernel that still matches
    the description or the reason for the name fcheck.

    The need for better names became apparent in the last round of
    discussion of this set of changes[1].

    [1] https://lkml.kernel.org/r/CAHk-=wj8BQbgJFLa+J0e=iT-1qpmCRTbPAJ8gd6MJQ=kbRPqyQ@mail.gmail.com
Link: https://lkml.kernel.org/r/20201120231441.29911-10-ebiederm@xmission.com
Change-Id: Ib880bd8feef1c5d75d2a018cd93a1d464485ab7b
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Cleanup: update stale file paths in LICENSE

Change-Id: I4849b19daa235b93a6435e57bd764128e43d691e
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Cleanup: use 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.

Change-Id: I8b59b3689aa38fb5f5a114f9d02f22274a5bff57
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Warn and return on fd overflow fdt

The fdt should only grow and iterate_fd() holds file_lock, which should
ensure the fdt does not change while the lock is taken but be cautious
and check anyway.

Change-Id: Icd6a3263026734cbe3f296f6087f79add4148a8f
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

cleanup: add correct error messages to lttng-get-syscall-inout.sh

The script argument parsing was modified in
commit 6ae73da43362 ("Fix syscall generator scripts") without adjusting
the error messages and comments.

Report the proper errors for the current arguments.

Change-Id: I86f4d16ffede1a6a48bc6ab5fe1e678ef340585b
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

cleanup: document 'pipe' syscall override

Change-Id: Iec84c10b774c1001ff2035024a1d05fdd31c8d9d
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

fix: net: udp: add IP/port data to the tracepoint udp/udp_fail_queue_rcv_skb (v6.10)

See upstream commit:

  commit e9669a00bba79442dd4862c57761333d6a020c24
  Author: Balazs Scheidler <bazsi77@gmail.com>
  Date:   Tue Mar 26 19:05:47 2024 +0100

    net: udp: add IP/port data to the tracepoint udp/udp_fail_queue_rcv_skb

    The udp_fail_queue_rcv_skb() tracepoint lacks any details on the source
    and destination IP/port whereas this information can be critical in case
    of UDP/syslog.

Change-Id: I0c337c5817b0a120298cbf5088d60671d9625b0d
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

fix: close_on_exec(): pass files_struct instead of fdtable (v6.10)

See upstream commit:

  commit f60d374d2cc88034385265d193a38e3f4a4b430c
  Author: Al Viro <viro@zeniv.linux.org.uk>
  Date:   Thu Jan 4 21:35:38 2024 -0500

    close_on_exec(): pass files_struct instead of fdtable

    both callers are happier that way...

Change-Id: I8cdabb073c2090842b27b74954d86cb486c43b3e
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

fix: btrfs: move ->parent and ->ref_root into btrfs_delayed_ref_node (v6.10)

See upstream commit:

  commit cf4f04325b2b27efa5697ba0ea4c1abdee0035b4
  Author: Josef Bacik <josef@toxicpanda.com>
  Date:   Fri Apr 12 22:57:13 2024 -0400

    btrfs: move ->parent and ->ref_root into btrfs_delayed_ref_node

    These two members are shared by both the tree refs and data refs, so
    move them into btrfs_delayed_ref_node proper.  This allows us to greatly
    simplify the comparison code, as the shared refs always only sort on
    parent, and the non shared refs always sort first on ref_root, and then
    only data refs sort on their specific fields.

Change-Id: Ib7c92cc4bb8d674ac66ccfa25c03476f7adaaf90
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

fix: btrfs: simplify delayed ref tracepoints (v6.10)

See upstream commit:

  commit 1bff6d4f873790cfc675afce9860208576508c5a
  Author: Josef Bacik <josef@toxicpanda.com>
  Date:   Fri Apr 12 20:27:00 2024 -0400

    btrfs: simplify delayed ref tracepoints

    Now that all of the delayed ref information is in the delayed ref node,
    drastically simplify the delayed ref tracepoints by simply passing in
    the btrfs_delayed_ref_node and populating the tracepoints with the
    values from the structure itself.

Change-Id: Ic90bc23d6aa558baec33adc33b4d21e052e83375
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix mm_vmscan_lru_isolate tracepoint for RHEL 9.4 kernel

Redhat has moved to using the format first found in the 6.7 kernel
for the mm_vmscan_lru_isolate tracepoint.

Change-Id: I2aa84769c0070458d902e9a0305488d6d8a380e1
Signed-off-by: Martin Hicks <martin@sr-research.com>
Signed-off-by: Kienan Stewart <kstewart@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

fix: Add missing 'pselect6_time32' and 'ppoll_time32' syscall overrides

The instrumentation currently has overrides to the generated syscall
tracepoints of 'ppoll' and 'pselect6' to extract additional information
from the parameters.

On arm-32 and x86-32 these 2 syscalls were renamed to 'ppoll_time32' and
'pselect6_time32' and new syscalls using 64-bit time_t were introduced
with the old names. This results in missing overrides on these
architectures for the 32-bit variants that were renamed.

Add the '_time32' overrides to restore the previous behavior.

Change-Id: I81e3a3ddc3f3cea58d86edcdf4a1fc9b600637c2
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

page alloc wrapper: Fix get_pfnblock_flags_mask prototype

The canary __canary__get_pfnblock_flags_mask has never done its job of
detecting changes to the prototype of get_pfnblock_flags_mask because
it was actually calling the wrapper, because the wrapper/page_alloc.h
header maps get_pfnblock_flags_mask to wrapper_get_pfnblock_flags_mask.

Unfortunately, this wrapper is included by page_alloc.c only _after_ the
linux/pageblock-flags.h header is included, which means the
get_pfnblock_flags_mask prototype does _not_ have the wrapper prefix,
which prevents it from being useful for any kind of type validation.

This has been detected by a compiler warning stating that
wrapper_get_pfnblock_flags_mask() does not have a prior declaration.

Move the wrapper/page_alloc.h include _before_ including
pageblock-flags.h. This ensures the declaration has the wrapper_ prefix,
and therefore the compiler compares the declaration with the definition
of wrapper_get_pfnblock_flags_mask within page_alloc.c. The canary
function can be removed because it is redundant with this type check.

With this proper type check in place, we notice the following two
changes upstream:

commit 535b81e209219 ("mm/page_alloc.c: remove unnecessary end_bitidx for [set|get]_pfnblock_flags_mask()")
introduced in v5.9 removes the end_bitidx argument.

commit ca891f41c4c79 ("mm: constify get_pfnblock_flags_mask and get_pfnblock_migratetype")
introduced in v5.14 adds a const qualifier to the struct page pointer.

Adapt the code to match the evolution of this prototype.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I51b7871edfbff0f74ba1cf4d0ad988eb8d642b4e

lttng probe: include events-internal.h

Include events-internal.h for the declarations of lttng_logger_init and
lttng_logger_exit.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I14968060c309083f90a282f186f3c635f1ebfd8d

uprobes: Remove dead code

lttng_uprobes_destroy_event_notifier_private is now unused. Remove it.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Ia995c60691f68090b6853b2deb0d265b1d4a047e

syscalls: Remove unused duplicated code

lttng_abi_syscall_list() was moved to src/lttng-abi.c within the 2.13
refactoring. Remove this unused copy.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Iabbab3b576e3d85bc5ac9831729a5786b5c5f224

statedump: Add missing events-internal.h include

Include events-internal.h for the declaration of
lttng_statedump_start().

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Ieda391aa0d780113efe1d517d8bc5aedb2095a2c

lttng-events: Remove dead code

Functions lttng_event_notifier_enabler_enable and
lttng_event_notifier_enabler_disable are unused since the 2.13
refactoring, remove them.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I18d0d483bf54cbc7d158413f27111271c68ac37d

lttng-events: Add missing static

get_tracker() and lttng_metadata_printf() are only used within the
compile unit, mark them as static.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Ie454c85cc29a30d964922fcfe1f88f3fb91bbc8f

event notifier: Add missing static

Mark capture_sequence() static because it is only used within the
compile unit.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I003e5cf016fbf2f2df24f4550a6c285e020956d0

context callstack: Add missing static

lttng_cs_event_fields() is only used within the compile unit, mark it
static.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I3435c6de411a0671de86ecdbcb3e1ea019d908e6

lttng-clock: Add missing lttng/events-internal.h include

Needed for lttng_clock_ref and lttng_clock_unref declarations.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Idb21d942b9e2151f1d5a78b31b28ca1ac455719b

lttng-calibrate: Add missing static and include

Include lttng/events-internal.h for the lttng_calibrate
declaration. Make lttng_calibrate_kretprobe static.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Ia18aa60e69cae7a16ed7d17c8297d7ad3bb3aca2

lttng-bytecode: Remove dead code

Functions lttng_filter_enabler_attach_bytecode and
lttng_free_enabler_filter_bytecode are unused since the
refactoring of lttng 2.13. Remove them.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I2abbb3906cdb5c1b7fa9c27c7871a51af7697832

lttng-abi: Add missing static to function definitions

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Icc6928df5a47c96a560e18b2c854780afbcf6307

ring buffer: Add missing static to function definitions

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I80c03d8c8879777e37d24c3574ba7bdea512446a

blkdev wrapper: Fix constness warning

Upstream commit f8c7511db009d ("block: make block_class constant")
makes the block_class const. Reflect this change in the lttng-modules
canary function.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Ib3aadd3dedc413f8370b9739f200ce9663c38d99

Rename "tsc" to "timestamp"

Naming timestamps "TSC" or "tsc" is an historical artefact dating from
the implementation of libringbuffer, where the initial intent was to use
the x86 "rdtsc" instruction directly, which ended up not being what was
done in reality.

Rename uses of "TSC" and "tsc" to "timestamp" to clarify things and
don't require reviewers to be fluent in x86 instruction set.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I09437b0cf6db79600ed1a423d1f6df0344f5c9f7

Fix: timer_expire_entry changed in 4.19.312

See upstream commit:

    commit bbb5b1c060d73ca96ccc8cceaa81f5e1a96e8fa4
    Author: Anna-Maria Gleixner <anna-maria@linutronix.de>
    Date:   Thu Mar 21 13:09:21 2019 +0100

        timer/trace: Improve timer tracing

        [ Upstream commit f28d3d5346e97e60c81f933ac89ccf015430e5cf ]

        Timers are added to the timer wheel off by one. This is required in
        case a timer is queued directly before incrementing jiffies to prevent
        early timer expiry.

        When reading a timer trace and relying only on the expiry time of the timer
        in the timer_start trace point and on the now in the timer_expiry_entry
        trace point, it seems that the timer fires late. With the current
        timer_expiry_entry trace point information only now=jiffies is printed but
        not the value of base->clk. This makes it impossible to draw a conclusion
        to the index of base->clk and makes it impossible to examine timer problems
        without additional trace points.

        Therefore add the base->clk value to the timer_expire_entry trace
        point, to be able to calculate the index the timer base is located at
        during collecting expired timers.

Change-Id: I2ebdbb637db0966ff51f45bf66916a59a496b50c
Signed-off-by: Kienan Stewart <kstewart@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

ring buffer: Use cpu_dcache_is_aliasing()

Upstream Linux commit 8690bbcf3b7 ("Introduce cpu_dcache_is_aliasing()
across all architectures") allows checking whether the architecture has
aliasing data caches more accurately. This will be present in upstream
Linux v6.9 (currently in v6.9-rc3).

I expect this to improve the ring buffer performance on ARM64 and
32-bit ARM with non-aliasing data caches.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I3e29966b8c8cab098d57437a11f1f94c53a9e186

Fix: dev_base_lock removed in linux 6.9-rc1

See upstream commit:

    commit 1b3ef46cb7f2618cc0b507393220a69810f6da12
    Author: Eric Dumazet <edumazet@google.com>
    Date:   Tue Feb 13 06:32:45 2024 +0000

        net: remove dev_base_lock

        dev_base_lock is not needed anymore, all remaining users also hold RTNL.

Change-Id: I6b07e6eed07fd398302ca14d23162ed24d74df15
Signed-off-by: Kienan Stewart <kstewart@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: mm_compaction_migratepages changed in linux 6.9-rc1

See upstream commit:

    commit ab755bf4249b992fc2140d615ab0a686d50765b4
    Author: Baolin Wang <baolin.wang@linux.alibaba.com>
    Date:   Tue Feb 20 14:16:31 2024 +0800

        mm: compaction: update the cc->nr_migratepages when allocating or freeing the freepages

        Currently we will use 'cc->nr_freepages >= cc->nr_migratepages' comparison
        to ensure that enough freepages are isolated in isolate_freepages(),
        however it just decreases the cc->nr_freepages without updating
        cc->nr_migratepages in compaction_alloc(), which will waste more CPU
        cycles and cause too many freepages to be isolated.

        So we should also update the cc->nr_migratepages when allocating or
        freeing the freepages to avoid isolating excess freepages.  And I can see
        fewer free pages are scanned and isolated when running thpcompact on my
        Arm64 server:

                                               k6.7         k6.7_patched
        Ops Compaction pages isolated      120692036.00   118160797.00
        Ops Compaction migrate scanned     131210329.00   154093268.00
        Ops Compaction free scanned       1090587971.00  1080632536.00
        Ops Compact scan efficiency               12.03          14.26

        Moreover, I did not see an obvious latency improvements, this is likely
        because isolating freepages is not the bottleneck in the thpcompact test
        case.

                                      k6.7                  k6.7_patched
        Amean     fault-both-1      1089.76 (   0.00%)     1080.16 *   0.88%*
        Amean     fault-both-3      1616.48 (   0.00%)     1636.65 *  -1.25%*
        Amean     fault-both-5      2266.66 (   0.00%)     2219.20 *   2.09%*
        Amean     fault-both-7      2909.84 (   0.00%)     2801.90 *   3.71%*
        Amean     fault-both-12     4861.26 (   0.00%)     4733.25 *   2.63%*
        Amean     fault-both-18     7351.11 (   0.00%)     6950.51 *   5.45%*
        Amean     fault-both-24     9059.30 (   0.00%)     9159.99 *  -1.11%*
        Amean     fault-both-30    10685.68 (   0.00%)    11399.02 *  -6.68%*

Change-Id: I103a43fd1b549360b3fc978fd409b7c17ef3e192
Signed-off-by: Kienan Stewart <kstewart@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: ASoC add component to set_bias_level events in linux 6.9-rc1

See upstream commit:

    commit 6ef46a69ec32fe1cf56de67742fcd01af4bf48af
    Author: Luca Ceresoli <luca.ceresoli@bootlin.com>
    Date:   Wed Mar 6 10:30:00 2024 +0100

        ASoC: trace: add component to set_bias_level trace events

        The snd_soc_bias_level_start and snd_soc_bias_level_done trace events
        currently look like:

                   aplay-229   [000]  1250.140778: snd_soc_bias_level_start: card=vscn-2046 val=1
                   aplay-229   [000]  1250.140784: snd_soc_bias_level_done: card=vscn-2046 val=1
                   aplay-229   [000]  1250.140786: snd_soc_bias_level_start: card=vscn-2046 val=2
                   aplay-229   [000]  1250.140788: snd_soc_bias_level_done: card=vscn-2046 val=2
            kworker/u8:1-21    [000]  1250.140871: snd_soc_bias_level_start: card=vscn-2046 val=1
            kworker/u8:0-11    [000]  1250.140951: snd_soc_bias_level_start: card=vscn-2046 val=1
            kworker/u8:0-11    [000]  1250.140956: snd_soc_bias_level_done: card=vscn-2046 val=1
            kworker/u8:0-11    [000]  1250.140959: snd_soc_bias_level_start: card=vscn-2046 val=2
            kworker/u8:0-11    [000]  1250.140961: snd_soc_bias_level_done: card=vscn-2046 val=2
            kworker/u8:1-21    [000]  1250.167219: snd_soc_bias_level_done: card=vscn-2046 val=1
            kworker/u8:1-21    [000]  1250.167222: snd_soc_bias_level_start: card=vscn-2046 val=2
            kworker/u8:1-21    [000]  1250.167232: snd_soc_bias_level_done: card=vscn-2046 val=2
            kworker/u8:0-11    [000]  1250.167440: snd_soc_bias_level_start: card=vscn-2046 val=3
            kworker/u8:0-11    [000]  1250.167444: snd_soc_bias_level_done: card=vscn-2046 val=3
            kworker/u8:1-21    [000]  1250.167497: snd_soc_bias_level_start: card=vscn-2046 val=3
            kworker/u8:1-21    [000]  1250.167506: snd_soc_bias_level_done: card=vscn-2046 val=3

        There are clearly multiple calls, one per component, but they cannot be
        discriminated from each other.

        Change the ftrace events to also print the component name, to make it clear
        which part of the code is involved. This requires changing the passed value
        from a struct snd_soc_card, where the DAPM context is not kwown, to a
        struct snd_soc_dapm_context where it is obviously known but the a card
        pointer is also available.

        With this change, the resulting trace becomes:

                   aplay-247   [000]  1436.357332: snd_soc_bias_level_start: card=vscn-2046 component=(none) val=1
                   aplay-247   [000]  1436.357338: snd_soc_bias_level_done: card=vscn-2046 component=(none) val=1
                   aplay-247   [000]  1436.357340: snd_soc_bias_level_start: card=vscn-2046 component=(none) val=2
                   aplay-247   [000]  1436.357343: snd_soc_bias_level_done: card=vscn-2046 component=(none) val=2
            kworker/u8:4-215   [000]  1436.357437: snd_soc_bias_level_start: card=vscn-2046 component=ff560000.codec val=1
            kworker/u8:5-231   [000]  1436.357518: snd_soc_bias_level_start: card=vscn-2046 component=ff320000.i2s val=1
            kworker/u8:5-231   [000]  1436.357523: snd_soc_bias_level_done: card=vscn-2046 component=ff320000.i2s val=1
            kworker/u8:5-231   [000]  1436.357526: snd_soc_bias_level_start: card=vscn-2046 component=ff320000.i2s val=2
            kworker/u8:5-231   [000]  1436.357528: snd_soc_bias_level_done: card=vscn-2046 component=ff320000.i2s val=2
            kworker/u8:4-215   [000]  1436.383217: snd_soc_bias_level_done: card=vscn-2046 component=ff560000.codec val=1
            kworker/u8:4-215   [000]  1436.383221: snd_soc_bias_level_start: card=vscn-2046 component=ff560000.codec val=2
            kworker/u8:4-215   [000]  1436.383231: snd_soc_bias_level_done: card=vscn-2046 component=ff560000.codec val=2
            kworker/u8:5-231   [000]  1436.383468: snd_soc_bias_level_start: card=vscn-2046 component=ff320000.i2s val=3
            kworker/u8:5-231   [000]  1436.383472: snd_soc_bias_level_done: card=vscn-2046 component=ff320000.i2s val=3
            kworker/u8:4-215   [000]  1436.383503: snd_soc_bias_level_start: card=vscn-2046 component=ff560000.codec val=3
            kworker/u8:4-215   [000]  1436.383513: snd_soc_bias_level_done: card=vscn-2046 component=ff560000.codec val=3

Change-Id: I959f1680c002acdf29828b968d3975247f5433d8
Signed-off-by: Kienan Stewart <kstewart@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: ASoC snd_doc_dapm on linux 6.9-rc1

See upstream commit:

    commit 7df3eb4cdb6bbfa482f51548b9fd47c2723c68ba
    Author: Luca Ceresoli <luca.ceresoli@bootlin.com>
    Date:   Wed Mar 6 10:30:01 2024 +0100

        ASoC: trace: add event to snd_soc_dapm trace events

        Add the event value to the snd_soc_dapm_start and snd_soc_dapm_done trace
        events to make them more informative.

        Trace before:

                   aplay-229   [000]   250.140309: snd_soc_dapm_start:   card=vscn-2046
                   aplay-229   [000]   250.167531: snd_soc_dapm_done:    card=vscn-2046
                   aplay-229   [000]   251.169588: snd_soc_dapm_start:   card=vscn-2046
                   aplay-229   [000]   251.195245: snd_soc_dapm_done:    card=vscn-2046

        Trace after:

                   aplay-214   [000]   693.290612: snd_soc_dapm_start:   card=vscn-2046 event=1
                   aplay-214   [000]   693.315508: snd_soc_dapm_done:    card=vscn-2046 event=1
                   aplay-214   [000]   694.537349: snd_soc_dapm_start:   card=vscn-2046 event=2
                   aplay-214   [000]   694.563241: snd_soc_dapm_done:    card=vscn-2046 event=2

Change-Id: If0d33544b8dd1dfb3d12ca9390892190fc0444b0
Signed-off-by: Kienan Stewart <kstewart@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: support ext4_journal_start on EL 8.4+

The lower value of the EL range, 240.15.1, corresponds to the first
import of EL r8 kernels into Rocky Linux's kernel staging repo.
The change may have been introduced in an earlier RHEL 8 kernel,
prior to the history of imports into Rocky.

Change-Id: Ibec02b382478bee33947d079f33835823827f4c5
Signed-off-by: Kienan Stewart <kstewart@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: build kvm probe on EL 8.4+

The lower value of the EL range, 240.15.1, corresponds to the first
import of EL r8 kernels into Rocky Linux's kernel staging repo.
The change may have been introduced in an earlier RHEL 8 kernel,
prior to the history of imports into Rocky.

Change-Id: Icefe472d43e28cc09746e9e046b12299609ebab1
Signed-off-by: Kienan Stewart <kstewart@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: correct RHEL range for kmem_cache_free define

When compiling against RHEL 8.5 kernels, lttng-modules builds fail
with the following error:

```
lttng-modules/src/probes/../../include/lttng/tracepoint-event-impl.h:133:6: error: conflicting types for ‘trace_kmem_
cache_free’; have ‘void(long unsigned int,  const void *)’
```

The original range was introduced in commit
89d917153fc52c1e5b0ddabf8ee078897656b263 which tested against RHEL 8.6
and not RHEL 8.5.

Change-Id: Icff98c15415ce8e1e95a10974cd65ed6e84cd00a
Signed-off-by: Kienan Stewart <kstewart@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

docs: Add supported versions and fix-backport policy

Change-Id: I5d6da21b9541f838cb326263eff8c1448e37fc55
Signed-off-by: Kienan Stewart <kstewart@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: Correct minimum version in jbd2 SLE kernel range

This range was introduced in commit b49650509ff072d37ec112cf45a5f14f382c9a31;
however, the range is wrong and worked because the kernel versions
(eg. `5.14.21-150400.24.100-default`) were evaluated to values
greater than `LTTNG_SLE_KERNEL_RANGE(5,14,21,24,46,1)`.

As a result builds of lttng-modules against older versions of SLE
kernels failed.

Change-Id: I23d97d84a23c7b24e957fe943932d6aefbe1b409
Signed-off-by: Kienan Stewart <kstewart@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

Fix: Handle recent SLE major version codes

Starting in early 2022, the SLE linux version codes changed from the
previous style `5.3.18-59.40.1` to a new convention in which the major
version is a compound number consisting of the major release version,
the service pack version, and the auxillary version (currently unused
from my understanding) similar to the following `5.3.18-150300.59.43.1`[1].

The newer values used in the SLE major version causes the integer
value to "overflow" the expected number of digits and the comparisons
may fail. The `LTTNG_SLE_KERNEL_VERSION` macro also multiplies the
`LTTNG_KERNEL_VERSION` by `100000000ULL` which doesn't work in all
situations, as the resulting value is too large to be stored fully in
an `unsigned long long`.

Example of previous results:

```
// Example range comparison. True or false depending on the value of
// `LTTNG_SLE_VERSION_CODE` and `LTTNG_LINUX_VERSION_CODE`.
LTTNG_SLE_KERNEL_RANGE(5,15,21,150400,24,46, 5,15,0,0,0,0);

// Note: values printed with `%ull`
LTTNG_SLE_KERNEL_VERSION(5,15,21,24,26,1); // 6106486698364570153
LTTNG_SLE_KERNEL_VERSION(5,15,0,0,0,0);    // 0
LTTNG_KERNEL_VERSION(5,15,0);              // 84869120

// Corrected SLE version codes
LTTNG_SLE_KERNEL_VERSION(5,14,21,150400,24,26); // 14918348902249793914
LTTNG_SLE_KERNEL_VERSION(5,14,21,150400,24,46); // 14918348902249793934
LTTNG_SLE_KERNEL_VERSION(5,15,0,150400,0,0));   // 6971507145825058816
```

`LTTNG_KERNEL_VERSION` packs the kernel version into a 32-bit integer;
however, using that type of packing on the SLE kernel version will not
work well:

* Major: `150400` needs 18 bits
* Minor: may exceed 127, requires 8 bits (eg. `4.12.14-150100.197.148.1`)
* Patch: may exceed 127, requires 8 bits (eg. `5.3.18-150300.59.124.1`)

In this patch, the SLE version is packed into a 64-bit integer
with 48 bits for the major version, 8 bits for each of the minor and
patch versions.

As a result of packing the SLE version into a 64-bit integer,
it is not possible to coherently combine an `LTTNG_KERNEL_VERSION` and
an `LTTNG_SLE_KERNEL_VERSION`. Doing so would require an integer
larger than 64-bits. Therefore, the `LTTNG_SLE_KERNEL_RANGE` macro has
been adjusted to perform the range comparisons using the two values
separately. The usage of the `LTTNG_SLE_KERNEL_RANGE` remains
unchanged, as `LTTNG_SLE_VERSION` is only used inside that macro.

Using the adjusted macros:

```
// Example range comparison. True or false depending on the value of
// `LTTNG_SLE_VERSION_CODE` and `LTTNG_LINUX_VERSION_CODE`.
LTTNG_SLE_KERNEL_RANGE(5,15,21,150400,24,46, 5,15,0,0,0,0);

// Note: values printed with `%ull`
LTTNG_SLE_VERSION(24,26,1); // 1579521
LTTNG_SLE_VERSION(0,0,0);   // 0
LTTNG_KERNEL_VERSION(5,15,0);      // 84869120

// Corrected SLE version codes
LTTNG_SLE_VERSION(150400,24,26); // 9856620570
LTTNG_SLE_VERSION(150400,24,46); // 9856620590
LTTNG_SLE_VERSION(150400,0,0));  // 9863168000
```

Known drawbacks
===============

It's possible that future releases of SLE kernels have minor or patch
values that exceed 255 (SLE15SP1 has a release using `197`, for example),
requiring an adjustment to using more bits for those fields when
packing into a 64-bit integer.

The schema of multiplying an `LTTNG_KERNEL_VERSION` by a large value
is used for other distributions. RHEL in particular uses
`100000000ULL`, which could lead to overflow issues with certain
comparisons similar to the previous behaviour of
`LTTNG_SLE_KERNEL_VERSION(5,15,0,0,0,0);`.

[1]: https://www.suse.com/support/kb/doc/?id=000019587#SLE15SP4

Change-Id: Iaa90bfa422e47213a13829cdf008ab20d7484cab
Signed-off-by: Kienan Stewart <kstewart@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>