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.
Ovidiu Panait [Thu, 14 May 2020 10:05:24 +0000 (13:05 +0300)]
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.
...
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.
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.
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.
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.
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().
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().
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".
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
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.
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>
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>
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>
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>
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>
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>
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>
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
Michael Jeanson [Mon, 24 Feb 2020 16:30:22 +0000 (11:30 -0500)]
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().
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>
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.
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:
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.
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.
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.
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.
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>
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.
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.
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>
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>
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.
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. ]
Michael Jeanson [Tue, 19 Feb 2019 21:14:38 +0000 (16:14 -0500)]
Cleanup: statedump process state event pid namespace fields
Now that we have namespace specific events in the statedump,
remove the duplicated information in the process state event
and make it a single event instead of recursing on the pid
namespace hierarchy.
Signed-off-by: Michael Jeanson <mjeanson@efficios.com> Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Michael Jeanson [Tue, 12 Feb 2019 14:47:34 +0000 (09:47 -0500)]
Add namespaces statedump
Add a statedump event for each type of namespace.
The pid ns was already implemented as part of the lttng_statedump_process_state
event, move the "vtid" and "vpid" fields to the new
lttng_statedump_process_pid_ns event.
Signed-off-by: Michael Jeanson <mjeanson@efficios.com> Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Michael Jeanson [Tue, 12 Feb 2019 14:43:24 +0000 (09:43 -0500)]
Add namespace contexts
Add a context for each available kernel namespace which currently are :
cgroup, ipc, mnt, net, pid, user and uts. The id chosen to identify the
namespaces is the inode number of the file representing each one of them
in the proc filesystem. This was instroduced in v3.8.0 in this commit :
proc: Usable inode numbers for the namespace file descriptors.
Assign a unique proc inode to each namespace, and use that
inode number to ensure we only allocate at most one proc
inode for every namespace in proc.
A single proc inode per namespace allows userspace to test
to see if two processes are in the same namespace.
...
Prior to this there is no unique identifier for a namespace that is
available to both the kernel and userspace. Enabling any of these
contexts on a kernel that is too old or doesn't have the proper features
enabled will fail and return -ENOSYS.
Per namespace particularities :
- Cgroup
- Introduced in 4.6.0
- CONFIG_CGROUPS
- IPC
- Introduced in 2.6.25
- CONFIG_IPC_NS
- MNT
- Introduced in 2.6.20
- The mnt_namespace struct is defined in a private header
- NET
- Introduced in 2.6.24
- CONFIG_NET_NS
- PID
- Introduced in 2.6.20
- CONFIG_PID_NS
- User
- Introduced in 2.6.23
- CONFIG_USER_NS
- UTS
- Introduced in 2.6.19
- CONFIG_UTS_NS
Signed-off-by: Michael Jeanson <mjeanson@efficios.com> Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Jonathan Rajotte [Tue, 13 Aug 2019 18:14:24 +0000 (14:14 -0400)]
Add metadata env fields
Add the following fields:
- tracer_buffering_scheme
The buffering scheme used by the tracer. lttng-modules sole
buffering scheme is "global".
- trace_name
The name of the trace. Use the session name.
Jonathan Rajotte [Tue, 13 Aug 2019 18:14:23 +0000 (14:14 -0400)]
Introduce LTTNG_KERNEL_SESSION_SET_NAME
The tracer controller (lttng-sessiond) can now inform the kernel tracer
of the name of the created session. This will allow the tracer to
propagate the information inside the trace metadata under a "env" field.
This information is normally inferred from the generated folder
structure where a trace rests.
Fix: lttng-tracepoint module notifier should return NOTIFY_OK
Module notifiers should return NOTIFY_OK on success rather than the
value 0. The return value 0 does not seem to have any ill side-effects
in the notifier chain caller, but it is preferable to respect the API
requirements in case this changes in the future.
Notifiers can encapsulate a negative errno value with
notifier_from_errno(), but this is not needed by the LTTng tracepoint
notifier.
The approach taken in this notifier is to just print a console warning
on error, because tracing failure should not prevent loading a module.
So we definitely do not want to stop notifier iteration. Returning
an error without stopping iteration is not really that useful, because
only the return value of the last callback is returned to notifier chain
caller.
Fix: Don't print ring-buffer's records count when it is not used
The teardown of a ring buffer causes a number of diagnostic messages
to be printed using printk. One of those contains the "records
count", which is only updated when lttng-modules is built with
LTTNG_RING_BUFFER_COUNT_EVENTS defined.
Move the "records count" printing to a different function and stub it
out when LTTNG_RING_BUFFER_COUNT_EVENTS is not defined
(default configuration).
This eliminates messages of the following form from the dmesg output
when an LTTng session is torn down.
[...] ring buffer relay-discard, cpu 0: 0 records written, 0 records overrun
Fix: do not set quiescent state on channel destroy
Setting the quiescent state to true for each stream at channel
destruction is not useful: there are no readers left anyway at
that stage.
The side-effect perceived of setting this quiescent state on
destroy is that the metadata stream ends up with an empty last
packet (due to flush_empty performed when setting the quiescent state)
which is never consumed. This shows up in the lttng-modules error
reporting.
Fix: ring_buffer_frontend.c: init read timer with uninitialized flags
For the config->alloc RING_BUFFER_ALLOC_GLOBAL (metadata channel), the
read timer flags argument is uninitialized.
Found by Coverity:
CID 1401114 (#1 of 1): Uninitialized scalar variable (UNINIT)
6. uninit_use_in_call: Using uninitialized value flags when calling init_timer_key.
Split the callstack code: keep boilerplate code within the
C implementation file, and move the parts which depend on the
"legacy" (pre-stackwalk) stacktrace kernel API to a separate
implementation header.
This is a preparation step to introduce a new implementation
header for the stackwalk API, added in Linux 5.2 and gradually
integrated within each architecture.
random: only read from /dev/random after its pool has received 128 bits
Immediately after boot, we allow reads from /dev/random before its
entropy pool has been fully initialized. Fix this so that we don't
allow this until the blocking pool has received 128 bits.
We do this by repurposing the initialized flag in the entropy pool
struct, and use the initialized flag in the blocking pool to indicate
whether it is safe to pull from the blocking pool.
To do this, we needed to rework when we decide to push entropy from the
input pool to the blocking pool, since the initialized flag for the
input pool was used for this purpose. To simplify things, we no
longer use the initialized flag for that purpose, nor do we use the
entropy_total field any more.
Signed-off-by: Michael Jeanson <mjeanson@efficios.com> Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
mm: move recent_rotated pages calculation to shrink_inactive_list()
Patch series "mm: Generalize putback functions"]
putback_inactive_pages() and move_active_pages_to_lru() are almost
similar, so this patchset merges them ina single function.
This patch (of 4):
The patch moves the calculation from putback_inactive_pages() to
shrink_inactive_list(). This makes putback_inactive_pages() looking more
similar to move_active_pages_to_lru().
To do that, we account activated pages in reclaim_stat::nr_activate.
Since a page may change its LRU type from anon to file cache inside
shrink_page_list() (see ClearPageSwapBacked()), we have to account pages
for the both types. So, nr_activate becomes an array.
Previously we used nr_activate to account PGACTIVATE events, but now we
account them into pgactivate variable (since they are about number of
pages in general, not about sum of hpage_nr_pages).
Signed-off-by: Michael Jeanson <mjeanson@efficios.com> Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
mm/vmscan: drop may_writepage and classzone_idx from direct reclaim begin template
There are three tracepoints using this template, which are
mm_vmscan_direct_reclaim_begin,
mm_vmscan_memcg_reclaim_begin,
mm_vmscan_memcg_softlimit_reclaim_begin.
Regarding mm_vmscan_direct_reclaim_begin,
sc.may_writepage is !laptop_mode, that's a static setting, and
reclaim_idx is derived from gfp_mask which is already show in this
tracepoint.
Regarding mm_vmscan_memcg_reclaim_begin,
may_writepage is !laptop_mode too, and reclaim_idx is (MAX_NR_ZONES-1),
which are both static value.
mm_vmscan_memcg_softlimit_reclaim_begin is the same with
mm_vmscan_memcg_reclaim_begin.
So we can drop them all.
Signed-off-by: Michael Jeanson <mjeanson@efficios.com> Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
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.
Signed-off-by: Michael Jeanson <mjeanson@efficios.com> Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
projects / lttng-modules.git / log
