tracing/ftrace: Allow for the traceonoff probe be unique to instances
Have the traceon/off function probe triggers affect only the instance they
are set in. This required making the trace_on/off accessible for other files
in the tracing directory.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
tracing/ftrace: Enable snapshot function trigger to work with instances
Modify the snapshot probe trigger to work with instances. This way the
snapshot function trigger will only affect the instance that it is added to
in the set_ftrace_filter file.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
tracing/ftrace: Allow instances to have their own function probes
Pass around the local trace_array that is the descriptor for tracing
instances, when enabling and disabling probes. This by default sets the
enable/disable of event probe triggers to work with instances.
The other probes will need some more work to get them working with
instances.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
tracing/ftrace: Add a better way to pass data via the probe functions
With the redesign of the registration and execution of the function probes
(triggers), data can now be passed from the setup of the probe to the probe
callers that are specific to the trace_array it is on. Although, all probes
still only affect the toplevel trace array, this change will allow for
instances to have their own probes separated from other instances and the
top array.
That is, something like the stacktrace probe can be set to trace only in an
instance and not the toplevel trace array. This isn't implement yet, but
this change sets the ground work for the change.
When a probe callback is triggered (someone writes the probe format into
set_ftrace_filter), it calls register_ftrace_function_probe() passing in
init_data that will be used to initialize the probe. Then for every matching
function, register_ftrace_function_probe() will call the probe_ops->init()
function with the init data that was passed to it, as well as an address to
a place holder that is associated with the probe and the instance. The first
occurrence will have a NULL in the pointer. The init() function will then
initialize it. If other probes are added, or more functions are part of the
probe, the place holder will be passed to the init() function with the place
holder data that it was initialized to the last time.
Then this place_holder is passed to each of the other probe_ops functions,
where it can be used in the function callback. When the probe_ops free()
function is called, it can be called either with the rip of the function
that is being removed from the probe, or zero, indicating that there are no
more functions attached to the probe, and the place holder is about to be
freed. This gives the probe_ops a way to free the data it assigned to the
place holder if it was allocade during the first init call.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace: Dynamically create the probe ftrace_ops for the trace_array
In order to eventually have each trace_array instance have its own unique
set of function probes (triggers), the trace array needs to hold the ops and
the filters for the probes.
This is the first step to accomplish this. Instead of having the private
data of the probe ops point to the trace_array, create a separate list that
the trace_array holds. There's only one private_data for a probe, we need
one per trace_array. The probe ftrace_ops will be dynamically created for
each instance, instead of being static.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
tracing: Pass the trace_array into ftrace_probe_ops functions
Pass the trace_array associated to a ftrace_probe_ops into the probe_ops
func(), init() and free() functions. The trace_array is the descriptor that
describes a tracing instance. This will help create the infrastructure that
will allow having function probes unique to tracing instances.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
tracing: Have the trace_array hold the list of registered func probes
Add a link list to the trace_array to hold func probes that are registered.
Currently, all function probes are the same for all instances as it was
before, that is, only the top level trace_array holds the function probes.
But this lays the ground work to have function probes be attached to
individual instances, and having the event trigger only affect events in the
given instance. But that work is still to be done.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace: If the hash for a probe fails to update then free what was initialized
If the ftrace_hash_move_and_update_ops() fails, and an ops->free() function
exists, then it needs to be called on all the ops that were added by this
registration.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace: Have the function probes call their own function
Now that the function probes have their own ftrace_ops, there's no reason to
continue using the ftrace_func_hash to find which probe to call in the
function callback. The ops that is passed in to the function callback is
part of the probe_ops to call.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace: Have unregister_ftrace_function_probe_func() return a value
Currently unregister_ftrace_function_probe_func() is a void function. It
does not give any feedback if an error occurred or no item was found to
remove and nothing was done.
Change it to return status and success if it removed something. Also update
the callers to return that feedback to the user.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace: Add helper function ftrace_hash_move_and_update_ops()
The processes of updating a ops filter_hash is a bit complex, and requires
setting up an old hash to perform the update. This is done exactly the same
in two locations for the same reasons. Create a helper function that does it
in one place.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace: Remove data field from ftrace_func_probe structure
No users of the function probes uses the data field anymore. Remove it, and
change the init function to take a void *data parameter instead of a
void **data, because the init will just get the data that the registering
function was received, and there's no state after it is called.
The other functions for ftrace_probe_ops still take the data parameter, but
it will currently only be passed NULL. It will stay as a parameter for
future data to be passed to these functions.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace: Remove printing of data in showing of a function probe
None of the probe users uses the data field anymore of the entry. They all
have their own print() function. Remove showing the data field in the
generic function as the data field will be going away.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace: Remove unused unregister_ftrace_function_probe_all() function
There are no users of unregister_ftrace_function_probe_all(). The only probe
function that is used is unregister_ftrace_function_probe_func(). Rename the
internal static function __unregister_ftrace_function_probe() to
unregister_ftrace_function_probe_func() and make it global.
Also remove the PROBE_TEST_FUNC as it would be always set.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace: Convert the rest of the function trigger over to the mapping functions
As the data pointer for individual ips will soon be removed and no longer
passed to the callback function probe handlers, convert the rest of the function
trigger counters over to the new ftrace_func_mapper helper functions.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
tracing: Have the snapshot trigger use the mapping helper functions
As the data pointer for individual ips will soon be removed and no longer
passed to the callback function probe handlers, convert the snapshot
trigger counter over to the new ftrace_func_mapper helper functions.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace: Added ftrace_func_mapper for function probe triggers
In order to move the ops to the function probes directly, they need a way to
map function ips to their own data without depending on the infrastructure
of the function probes, as the data field will be going away.
New helper functions are added that are based on the ftrace_hash code.
ftrace_func_mapper functions are there to let the probes map ips to their
data. These can be allocated by the probe ops, and referenced in the
function callbacks.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
In preparation to cleaning up the probe function registration code, the
"data" parameter will eventually be removed from the probe->func() call.
Instead it will receive its own "ops" function, in which it can set up its
own data that it needs to map.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace: Move the function commands into the tracing directory
As nothing outside the tracing directory uses the function command mechanism,
I'm moving the prototypes out of the include/linux/ftrace.h and into the
local kernel/trace/trace.h header. I plan on making them hook to the
trace_array structure which is local to kernel/trace, and I do not want to
expose it to the rest of the kernel. This requires that the command functions
must also be local to tracing. But luckily nothing else uses them.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace: Move the probe function into the tracing directory
As nothing outside the tracing directory uses the function probes mechanism,
I'm moving the prototypes out of the include/linux/ftrace.h and into the
local kernel/trace/trace.h header. I plan on making them hook to the
trace_array structure which is local to kernel/trace, and I do not want to
expose it to the rest of the kernel. This requires that the probe functions
must also be local to tracing. But luckily nothing else uses them.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
selftests: ftrace: Add test to test reading of set_ftrace_file
The set_ftrace_file lists both functions that are filtered, as well as
function probes (triggers) that are attached to a function, like traceon or
stacktrace, etc. The reading of this file is not as trivial as most pseudo
files are, and there's been various bugs that have appeared in the past
when there's a mix of probes and functions listed. There's also a difference
when reading the file using dd with a block size of 1.
This test performs the following:
o Resets set_ftrace_filter
o Makes sure only "#### all functions enabled ####" is listed
(All checks uses cat, and dd with bs=1 and bs=100)
o Adds a traceon trigger to schedule
o Checks if only "#### all function enabled ####" and the trigger is there.
o Adds tracing of schedule
o Checks if only schedule and the trigger is there
o Adds tracing of do_IRQ as well
o Checks if only schedule, do_IRQ and the trigger is there
o Adds a traceon trigger to do_IRQ
o Checks if only schedule, do_IRQ and both triggers are there
o Removes tracing of do_IRQ
o Checks if only schedule and both triggers are there
o Removes tracing of schedule
o Checks if only "#### all functions enabled ####" and both triggers are there
o Removes the triggers
o Checks if only "#### all functions enabled ####" is there
o Adds tracing of schedule
o Checks if only schedule is there
o Adds tracing of do_IRQ
o Checks if only schedule and do_IRQ are there
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
selftests: ftrace: Add a selftest to test event enable/disable func trigger
This adds a test to enable and disable trace events via the function
triggers. It tests enabling and disabling the sched:sched_switch event via
the the event_enable and event_disable function triggers attached to the
schedule() kernel function.
The test does the following:
o disable all events
o disables or enables the sched_switch event
o writes schedule:event_enable/disable:sched:sched_switch into set_ftrace_filter
o 5 times it checks to make sure:
. Writes 0/1 into the sched_switch/enable
. Checks that the sched_switch/enable goes back to 1/0
o Resets the events
o writes schedule:event_enable/disable:sched:sched_switch:3 into set_ftrace_filter
o Does a loop of 3 to see that sched_switch/enable file gets updated
o Makes sure the sched_switch/enable stops getting updated
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
selftests: ftrace: Add a way to reset triggers in the set_ftrace_filter file
Just writing into the set_ftrace_filter file does not reset triggers, even
though it can reset the function list. Triggers require writing the trigger
name with a "!" prepended. It's worse that it requires the number if the
trigger has a count associated to it.
Add a reset_ftrace_filter function to the ftrace self tests to allow for the
tests to have a generic way to clear them. It also resets any functions that
are listed in that file as well.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Namhyung Kim [Mon, 17 Apr 2017 02:44:29 +0000 (11:44 +0900)]
selftests: ftrace: Add -l/--logdir option
In my virtual machine setup, running ftracetest failed on creating
LOG_DIR on a read-only filesystem. It'd be convenient to provide an
option to specify a different directory as log directory.
Namhyung Kim [Mon, 17 Apr 2017 02:44:28 +0000 (11:44 +0900)]
ftrace: Add 'function-fork' trace option
The function-fork option is same as event-fork that it tracks task
fork/exit and set the pid filter properly. This can be useful if user
wants to trace selected tasks including their children only.
tracing: Have the trace_event benchmark thread call cond_resched_rcu_qs()
The trace_event benchmark thread runs in kernel space in an infinite loop
while also calling cond_resched() in case anything else wants to schedule
in. Unfortunately, on a PREEMPT kernel, that makes it a nop, in which case,
this will never voluntarily schedule. That will cause synchronize_rcu_tasks()
to forever block on this thread, while it is running.
This is exactly what cond_resched_rcu_qs() is for. Use that instead.
Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace: Fix indexing of t_hash_start() from t_next()
t_hash_start() does not increment *pos, where as t_next() must. But when
t_next() does increment *pos, it must still pass in the original *pos to
t_hash_start() otherwise it will skip the first instance:
When two function probes are added to set_ftrace_filter, and then one of
them is removed, the update to the function locations is not performed, and
the record keeping of the function states are corrupted, and causes an
ftrace_bug() to occur.
This is easily reproducable by adding two probes, removing one, and then
adding it back again.
Cc: stable@vger.kernel.org Fixes: 59df055f1991 ("ftrace: trace different functions with a different tracer") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
tracing: Make sure rcu_irq_enter() can work for trace_*_rcuidle() trace events
Stack tracing discovered that there's a small location inside the RCU
infrastructure where calling rcu_irq_enter() does not work. As trace events
use rcu_irq_enter() it must make sure that it is functionable. A check
against rcu_irq_enter_disabled() is added with a WARN_ON_ONCE() as no trace
event should ever be used in that part of RCU. If the warning is triggered,
then the trace event is ignored.
Restructure the __DO_TRACE() a bit to get rid of the prercu and postrcu,
and just have an rcucheck that does the work from within the _DO_TRACE()
macro. gcc optimization will compile out the rcucheck=0 case.
rcu/tracing: Add rcu_disabled to denote when rcu_irq_enter() will not work
Tracing uses rcu_irq_enter() as a way to make sure that RCU is watching when
it needs to use rcu_read_lock() and friends. This is because tracing can
happen as RCU is about to enter user space, or about to go idle, and RCU
does not watch for RCU read side critical sections as it makes the
transition.
There is a small location within the RCU infrastructure that rcu_irq_enter()
itself will not work. If tracing were to occur in that section it will break
if it tries to use rcu_irq_enter().
Originally, this happens with the stack_tracer, because it will call
save_stack_trace when it encounters stack usage that is greater than any
stack usage it had encountered previously. There was a case where that
happened in the RCU section where rcu_irq_enter() did not work, and lockdep
complained loudly about it. To fix it, stack tracing added a call to be
disabled and RCU would disable stack tracing during the critical section
that rcu_irq_enter() was inoperable. This solution worked, but there are
other cases that use rcu_irq_enter() and it would be a good idea to let RCU
give a way to let others know that rcu_irq_enter() will not work. For
example, in trace events.
Another helpful aspect of this change is that it also moves the per cpu
variable called in the RCU critical section into a cache locale along with
other RCU per cpu variables used in that same location.
I'm keeping the stack_trace_disable() code, as that still could be used in
the future by places that really need to disable it. And since it's only a
static inline, it wont take up any kernel text if it is not used.
The tracing subsystem started using rcu_irq_entry() and rcu_irq_exit()
(with my blessing) to allow the current _rcuidle alternative tracepoint
name to be dispensed with while still maintaining good performance.
Unfortunately, this causes RCU's dyntick-idle entry code's tracing to
appear to RCU like an interrupt that occurs where RCU is not designed
to handle interrupts.
This commit fixes this problem by moving the zeroing of ->dynticks_nesting
after the offending trace_rcu_dyntick() statement, which narrows the
window of vulnerability to a pair of adjacent statements that are now
marked with comments to that effect.
tracing: Rename trace_active to disable_stack_tracer and inline its modification
In order to eliminate a function call, make "trace_active" into
"disable_stack_tracer" and convert stack_tracer_disable() and friends into
static inline functions.
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
There are certain parts of the kernel that cannot let stack tracing
proceed (namely in RCU), because the stack tracer uses RCU, and parts of RCU
internals cannot handle having RCU read side locks taken.
Add stack_tracer_disable() and stack_tracer_enable() functions to let RCU
stop stack tracing on the current CPU when it is in those critical sections.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
tracing: Replace the per_cpu() with __this_cpu*() in trace_stack.c
The updates to the trace_active per cpu variable can be updated with the
__this_cpu_*() functions as it only gets updated on the CPU that the variable
is on.
Thanks to Paul McKenney for suggesting __this_cpu_* instead of this_cpu_*.
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace: Add use of synchronize_rcu_tasks() with dynamic trampolines
The function tracer needs to be more careful than other subsystems when it
comes to freeing data. Especially if that data is actually executable code.
When a single function is traced, a trampoline can be dynamically allocated
which is called to jump to the function trace callback. When the callback is
no longer needed, the dynamic allocated trampoline needs to be freed. This
is where the issues arise. The dynamically allocated trampoline must not be
used again. As function tracing can trace all subsystems, including
subsystems that are used to serialize aspects of freeing (namely RCU), it
must take extra care when doing the freeing.
Before synchronize_rcu_tasks() was around, there was no way for the function
tracer to know that nothing was using the dynamically allocated trampoline
when CONFIG_PREEMPT was enabled. That's because a task could be indefinitely
preempted while sitting on the trampoline. Now with synchronize_rcu_tasks(),
it will wait till all tasks have either voluntarily scheduled (not on the
trampoline) or goes into userspace (not on the trampoline). Then it is safe
to free the trampoline even with CONFIG_PREEMPT set.
Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Alban Crequy [Mon, 3 Apr 2017 10:36:22 +0000 (12:36 +0200)]
tracing/kprobes: expose maxactive for kretprobe in kprobe_events
When a kretprobe is installed on a kernel function, there is a maximum
limit of how many calls in parallel it can catch (aka "maxactive"). A
kernel module could call register_kretprobe() and initialize maxactive
(see example in samples/kprobes/kretprobe_example.c).
But that is not exposed to userspace and it is currently not possible to
choose maxactive when writing to /sys/kernel/debug/tracing/kprobe_events
The default maxactive can be as low as 1 on single-core with a
non-preemptive kernel. This is too low and we need to increase it not
only for recursive functions, but for functions that sleep or resched.
This patch updates the format of the command that can be written to
kprobe_events so that maxactive can be optionally specified.
I need this for a bpf program attached to the kretprobe of
inet_csk_accept, which can sleep for a long time.
This patch includes a basic selftest:
> # ./ftracetest -v test.d/kprobe/
> === Ftrace unit tests ===
> [1] Kprobe dynamic event - adding and removing [PASS]
> [2] Kprobe dynamic event - busy event check [PASS]
> [3] Kprobe dynamic event with arguments [PASS]
> [4] Kprobes event arguments with types [PASS]
> [5] Kprobe dynamic event with function tracer [PASS]
> [6] Kretprobe dynamic event with arguments [PASS]
> [7] Kretprobe dynamic event with maxactive [PASS]
>
> # of passed: 7
> # of failed: 0
> # of unresolved: 0
> # of untested: 0
> # of unsupported: 0
> # of xfailed: 0
> # of undefined(test bug): 0
ftrace: Have init/main.c call ftrace directly to free init memory
Relying on free_reserved_area() to call ftrace to free init memory proved to
not be sufficient. The issue is that on x86, when debug_pagealloc is
enabled, the init memory is not freed, but simply set as not present. Since
ftrace was uninformed of this, starting function tracing still tries to
update pages that are not present according to the page tables, causing
ftrace to bug, as well as killing the kernel itself.
Instead of relying on free_reserved_area(), have init/main.c call ftrace
directly just before it frees the init memory. Then it needs to use
__init_begin and __init_end to know where the init memory location is.
Looking at all archs (and testing what I can), it appears that this should
work for each of them.
Reported-by: kernel test robot <xiaolong.ye@intel.com> Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
# dd if=set_ftrace_filter bs=1
schedule
do_IRQ
schedule:traceoff:unlimited
schedule:traceoff:unlimited
do_IRQ:traceoff:unlimited
98+0 records in
98+0 records out
98 bytes copied, 0.00265011 s, 37.0 kB/s
This is due to the way t_start() calls t_next() as well as the seq_file
calls t_next() and the state is slightly different between the two. Namely,
t_start() will call t_next() with a local "pos" variable.
By separating out the function listing from t_next() into its own function,
we can have better control of outputting the functions and the hash of
triggers. This simplifies the code.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
But if you read that file with dd, the output can change:
# dd if=/debug/tracing/set_ftrace_filter bs=1
#### all functions enabled ####
32+0 records in
32+0 records out
32 bytes copied, 7.0237e-05 s, 456 kB/s
This is because the "pos" variable is updated for the comment, but func_pos
is not. "func_pos" is used by the triggers (or hashes) to know how many
functions were printed and it bases its index from the pos - func_pos.
func_pos should be 1 to count for the comment printed. But since it is not,
t_hash_start() thinks that one trigger was already printed.
The cat gets to t_hash_start() via t_next() and not t_start() which updates
both pos and func_pos.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace: Return NULL at end of t_start() instead of calling t_hash_start()
The loop in t_start() of calling t_next() will call t_hash_start() if the
pos is beyond the functions and enters the hash items. There's no reason to
check if p is NULL and call t_hash_start(), as that would be redundant.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace: Assign iter->hash to filter or notrace hashes on seq read
Instead of testing if the hash to use is the filter_hash or the notrace_hash
at each iteration, do the test at open, and set the iter->hash to point to
the corresponding filter or notrace hash. Then use that directly instead of
testing which hash needs to be used each iteration.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace/x86: Do no run CPU sync when there is only one CPU online
Moving enabling of function tracing to early boot, even before scheduling is
enabled, means that it is not safe to enable interrupts. When function
tracing was enabled at boot up, it use to happen after scheduling and the
other CPUs were brought up. That required running a sync across all CPUs
when modifying the function hook locations in the code. To do the
synchronization, interrupts had to be enabled. Now function tracing can be
started before the other CPUs are brought up, and enabling interrupts in
that case is dangerous. As only tho boot CPU is active, there is no reason
to run the synchronization. If the online CPU count is one, do not bother
doing the synchronization. This removes the need to enable interrupts.
Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
One would think this is not an issue to keep as an inline. But because this
is used in the TRACE_EVENT() macro, it is extended for every tracepoint in
the system. Taking a look at a single tracepoint x86_irq_vector (was the
first one I randomly chosen). As trace_handle_return is used in the
TRACE_EVENT() macro of trace_raw_output_##call() we disassemble
trace_raw_output_x86_irq_vector and do a diff:
- is the original
+ is the out-of-line code
I removed identical lines that were different just due to different
addresses.
If you notice, the original has 22 bytes of text more than the out of line
version. As this is for every TRACE_EVENT() defined in the system, this can
become quite large.
ftrace: Allow for function tracing to record init functions on boot up
Adding a hook into free_reserve_area() that informs ftrace that boot up init
text is being free, lets ftrace safely remove those init functions from its
records, which keeps ftrace from trying to modify text that no longer
exists.
Note, this still does not allow for tracing .init text of modules, as
modules require different work for freeing its init code.
ftrace: Have function tracing start in early boot up
Register the function tracer right after the tracing buffers are initialized
in early boot up. This will allow function tracing to begin early if it is
enabled via the kernel command line.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
tracing: Postpone tracer start-up tests till the system is more robust
As tracing can now be enabled very early in boot up, even before some
critical system services (like scheduling), do not run the tracer selftests
until after early_initcall() is performed. If a tracer is registered before
such time, it is saved off in a list and the test is run when the system is
able to handle more diverse functions.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace: Move ftrace_init() to right after memory initialization
Initialize the ftrace records immediately after memory initialization, as
that is all that is required for the records to be created. This will allow
for future work to get function tracing started earlier in the boot process.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
tracing: Split tracing initialization into two for early initialization
Create an early_trace_init() function that will initialize the buffers and
allow for ealier use of trace_printk(). This will also allow for future work
to have function tracing start earlier at boot up.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Linus Torvalds [Mon, 20 Mar 2017 02:00:47 +0000 (19:00 -0700)]
mm/swap: don't BUG_ON() due to uninitialized swap slot cache
This BUG_ON() triggered for me once at shutdown, and I don't see a
reason for the check. The code correctly checks whether the swap slot
cache is usable or not, so an uninitialized swap slot cache is not
actually problematic afaik.
I've temporarily just switched the BUG_ON() to a WARN_ON_ONCE(), since
I'm not sure why that seemingly pointless check was there. I suspect
the real fix is to just remove it entirely, but for now we'll warn about
it but not bring the machine down.
Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Mon, 20 Mar 2017 01:49:28 +0000 (18:49 -0700)]
Merge tag 'powerpc-4.11-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull more powerpc fixes from Michael Ellerman:
"A couple of minor powerpc fixes for 4.11:
- wire up statx() syscall
- don't print a warning on memory hotplug when HPT resizing isn't
available
Thanks to: David Gibson, Chandan Rajendra"
* tag 'powerpc-4.11-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/pseries: Don't give a warning when HPT resizing isn't available
powerpc: Wire up statx() syscall
Linus Torvalds [Mon, 20 Mar 2017 01:11:13 +0000 (18:11 -0700)]
Merge branch 'parisc-4.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc fixes from Helge Deller:
- Mikulas Patocka added support for R_PARISC_SECREL32 relocations in
modules with CONFIG_MODVERSIONS.
- Dave Anglin optimized the cache flushing for vmap ranges.
- Arvind Yadav provided a fix for a potential NULL pointer dereference
in the parisc perf code (and some code cleanups).
- I wired up the new statx system call, fixed some compiler warnings
with the access_ok() macro and fixed shutdown code to really halt a
system at shutdown instead of crashing & rebooting.
* 'parisc-4.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Fix system shutdown halt
parisc: perf: Fix potential NULL pointer dereference
parisc: Avoid compiler warnings with access_ok()
parisc: Wire up statx system call
parisc: Optimize flush_kernel_vmap_range and invalidate_kernel_vmap_range
parisc: support R_PARISC_SECREL32 relocation in modules
Pull SCSI target fixes from Nicholas Bellinger:
"The bulk of the changes are in qla2xxx target driver code to address
various issues found during Cavium/QLogic's internal testing (stable
CC's included), along with a few other stability and smaller
miscellaneous improvements.
There are also a couple of different patch sets from Mike Christie,
which have been a result of his work to use target-core ALUA logic
together with tcm-user backend driver.
Finally, a patch to address some long standing issues with
pass-through SCSI export of TYPE_TAPE + TYPE_MEDIUM_CHANGER devices,
which will make folks using physical (or virtual) magnetic tape happy"
* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (28 commits)
qla2xxx: Update driver version to 9.00.00.00-k
qla2xxx: Fix delayed response to command for loop mode/direct connect.
qla2xxx: Change scsi host lookup method.
qla2xxx: Add DebugFS node to display Port Database
qla2xxx: Use IOCB interface to submit non-critical MBX.
qla2xxx: Add async new target notification
qla2xxx: Export DIF stats via debugfs
qla2xxx: Improve T10-DIF/PI handling in driver.
qla2xxx: Allow relogin to proceed if remote login did not finish
qla2xxx: Fix sess_lock & hardware_lock lock order problem.
qla2xxx: Fix inadequate lock protection for ABTS.
qla2xxx: Fix request queue corruption.
qla2xxx: Fix memory leak for abts processing
qla2xxx: Allow vref count to timeout on vport delete.
tcmu: Convert cmd_time_out into backend device attribute
tcmu: make cmd timeout configurable
tcmu: add helper to check if dev was configured
target: fix race during implicit transition work flushes
target: allow userspace to set state to transitioning
target: fix ALUA transition timeout handling
...
Linus Torvalds [Sun, 19 Mar 2017 22:45:02 +0000 (15:45 -0700)]
Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull device-dax fixes from Dan Williams:
"The device-dax driver was not being careful to handle falling back to
smaller fault-granularity sizes.
The driver already fails fault attempts that are smaller than the
device's alignment, but it also needs to handle the cases where a
larger page mapping could be established. For simplicity of the
immediate fix the implementation just signals VM_FAULT_FALLBACK until
fault-size == device-alignment.
One fix is for -stable to address pmd-to-pte fallback from the
original implementation, another fix is for the new (introduced in
4.11-rc1) pud-to-pmd regression, and a typo fix comes along for the
ride.
These have received a build success notification from the kbuild
robot"
Quinn Tran [Wed, 15 Mar 2017 16:48:55 +0000 (09:48 -0700)]
qla2xxx: Fix delayed response to command for loop mode/direct connect.
Current driver wait for FW to be in the ready state before
processing in-coming commands. For Arbitrated Loop or
Point-to- Point (not switch), FW Ready state can take a while.
FW will transition to ready state after all Nports have been
logged in. In the mean time, certain initiators have completed
the login and starts IO. Driver needs to start processing all
queues if FW is already started.
Quinn Tran [Wed, 15 Mar 2017 16:48:54 +0000 (09:48 -0700)]
qla2xxx: Change scsi host lookup method.
For target mode, when new scsi command arrive, driver first performs
a look up of the SCSI Host. The current look up method is based on
the ALPA portion of the NPort ID. For Cisco switch, the ALPA can
not be used as the index. Instead, the new search method is based
on the full value of the Nport_ID via btree lib.
Quinn Tran [Wed, 15 Mar 2017 16:48:52 +0000 (09:48 -0700)]
qla2xxx: Use IOCB interface to submit non-critical MBX.
The Mailbox interface is currently over subscribed. We like
to reserve the Mailbox interface for the chip managment and
link initialization. Any non essential Mailbox command will
be routed through the IOCB interface. The IOCB interface is
able to absorb more commands.
Following commands are being routed through IOCB interface
- Get ID List (007Ch)
- Get Port DB (0064h)
- Get Link Priv Stats (006Dh)
Quinn Tran [Wed, 15 Mar 2017 16:48:48 +0000 (09:48 -0700)]
qla2xxx: Allow relogin to proceed if remote login did not finish
If the remote port have started the login process, then the
PLOGI and PRLI should be back to back. Driver will allow
the remote port to complete the process. For the case where
the remote port decide to back off from sending PRLI, this
local port sets an expiration timer for the PRLI. Once the
expiration time passes, the relogin retry logic is allowed
to go through and perform login with the remote port.
Quinn Tran [Wed, 15 Mar 2017 16:48:47 +0000 (09:48 -0700)]
qla2xxx: Fix sess_lock & hardware_lock lock order problem.
The main lock that needs to be held for CMD or TMR submission
to upper layer is the sess_lock. The sess_lock is used to
serialize cmd submission and session deletion. The addition
of hardware_lock being held is not necessary. This patch removes
hardware_lock dependency from CMD/TMR submission.
Use hardware_lock only for error response in this case.
Quinn Tran [Wed, 15 Mar 2017 16:48:46 +0000 (09:48 -0700)]
qla2xxx: Fix inadequate lock protection for ABTS.
Normally, ABTS is sent to Target Core as Task MGMT command.
In the case of error, qla2xxx needs to send response, hardware_lock
is required to prevent request queue corruption.
Quinn Tran [Wed, 15 Mar 2017 16:48:45 +0000 (09:48 -0700)]
qla2xxx: Fix request queue corruption.
When FW notify driver or driver detects low FW resource,
driver tries to send out Busy SCSI Status to tell Initiator
side to back off. During the send process, the lock was not held.
tcmu: Convert cmd_time_out into backend device attribute
Instead of putting cmd_time_out under ../target/core/user_0/foo/control,
which has historically been used by parameters needed for initial
backend device configuration, go ahead and move cmd_time_out into
a backend device attribute.
In order to do this, tcmu_module_init() has been updated to create
a local struct configfs_attribute **tcmu_attrs, that is based upon
the existing passthrough_attrib_attrs along with the new cmd_time_out
attribute. Once **tcm_attrs has been setup, go ahead and point
it at tcmu_ops->tb_dev_attrib_attrs so it's picked up by target-core.
Also following MNC's previous change, ->cmd_time_out is stored in
milliseconds but exposed via configfs in seconds. Also, note this
patch restricts the modification of ->cmd_time_out to before +
after the TCMU device has been configured, but not while it has
active fabric exports.
Cc: Mike Christie <mchristi@redhat.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Mike Christie [Thu, 9 Mar 2017 08:42:09 +0000 (02:42 -0600)]
tcmu: make cmd timeout configurable
A single daemon could implement multiple types of devices
using multuple types of real devices that may not support
restarting from crashes and/or handling tcmu timeouts. This
makes the cmd timeout configurable, so handlers that do not
support it can turn if off for now.
Signed-off-by: Mike Christie <mchristi@redhat.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Mike Christie [Thu, 9 Mar 2017 08:42:08 +0000 (02:42 -0600)]
tcmu: add helper to check if dev was configured
This adds a helper to check if the dev was configured. It
will be used in the next patch to prevent updates to some
config settings after the device has been setup.
Signed-off-by: Mike Christie <mchristi@redhat.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Linus Torvalds [Sat, 18 Mar 2017 22:50:39 +0000 (15:50 -0700)]
Merge tag 'openrisc-for-linus' of git://github.com/openrisc/linux
Pull OpenRISC fixes from Stafford Horne:
"OpenRISC fixes for build issues that were exposed by kbuild robots
after 4.11 merge. All from allmodconfig builds. This includes:
- bug in the handling of 8-byte get_user() calls
- module build failure due to multile missing symbol exports"
* tag 'openrisc-for-linus' of git://github.com/openrisc/linux:
openrisc: Export symbols needed by modules
openrisc: fix issue handling 8 byte get_user calls
openrisc: xchg: fix `computed is not used` warning
Mike Christie [Thu, 2 Mar 2017 10:59:50 +0000 (04:59 -0600)]
target: fix race during implicit transition work flushes
This fixes the following races:
1. core_alua_do_transition_tg_pt could have read
tg_pt_gp_alua_access_state and gone into this if chunk:
if (!explicit &&
atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state) ==
ALUA_ACCESS_STATE_TRANSITION) {
and then core_alua_do_transition_tg_pt_work could update the
state. core_alua_do_transition_tg_pt would then only set
tg_pt_gp_alua_pending_state and the tg_pt_gp_alua_access_state would
not get updated with the second calls state.
2. core_alua_do_transition_tg_pt could be setting
tg_pt_gp_transition_complete while the tg_pt_gp_transition_work
is already completing. core_alua_do_transition_tg_pt then waits on the
completion that will never be called.
To handle these issues, we just call flush_work which will return when
core_alua_do_transition_tg_pt_work has completed so there is no need
to do the complete/wait. And, if core_alua_do_transition_tg_pt_work
was running, instead of trying to sneak in the state change, we just
schedule up another core_alua_do_transition_tg_pt_work call.
Note that this does not handle a possible race where there are multiple
threads call core_alua_do_transition_tg_pt at the same time. I think
we need a mutex in target_tg_pt_gp_alua_access_state_store.
Signed-off-by: Mike Christie <mchristi@redhat.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Mike Christie [Thu, 2 Mar 2017 10:59:49 +0000 (04:59 -0600)]
target: allow userspace to set state to transitioning
Userspace target_core_user handlers like tcmu-runner may want to set the
ALUA state to transitioning while it does implicit transitions. This
patch allows that state when set from configfs.
Signed-off-by: Mike Christie <mchristi@redhat.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Mike Christie [Thu, 2 Mar 2017 10:59:48 +0000 (04:59 -0600)]
target: fix ALUA transition timeout handling
The implicit transition time tells initiators the min time
to wait before timing out a transition. We currently schedule
the transition to occur in tg_pt_gp_implicit_trans_secs
seconds so there is no room for delays. If
core_alua_do_transition_tg_pt_work->core_alua_update_tpg_primary_metadata
needs to write out info to a remote file, then the initiator can
easily time out the operation.
Signed-off-by: Mike Christie <mchristi@redhat.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Mike Christie [Thu, 2 Mar 2017 05:13:26 +0000 (23:13 -0600)]
target: Use system workqueue for ALUA transitions
If tcmu-runner is processing a STPG and needs to change the kernel's
ALUA state then we cannot use the same work queue for task management
requests and ALUA transitions, because we could deadlock. The problem
occurs when a STPG times out before tcmu-runner is able to
call into target_tg_pt_gp_alua_access_state_store->
core_alua_do_port_transition -> core_alua_do_transition_tg_pt ->
queue_work. In this case, the tmr is on the work queue waiting for
the STPG to complete, but the STPG transition is now queued behind
the waiting tmr.
Note:
This bug will also be fixed by this patch:
http://www.spinics.net/lists/target-devel/msg14560.html
which switches the tmr code to use the system workqueues.
For both, I am not sure if we need a dedicated workqueue since
it is not a performance path and I do not think we need WQ_MEM_RECLAIM
to make forward progress to free up memory like the block layer does.
Signed-off-by: Mike Christie <mchristi@redhat.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Mike Christie [Thu, 2 Mar 2017 05:13:25 +0000 (23:13 -0600)]
target: fail ALUA transitions for pscsi
We do not setup the LU group for pscsi devices, so if you write
a state to alua_access_state that will cause a transition you will
get a NULL pointer dereference.
This patch will fail attempts to try and transition the path
for backend devices that set the TRANSPORT_FLAG_PASSTHROUGH_ALUA
flag.
Signed-off-by: Mike Christie <mchristi@redhat.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Mike Christie [Thu, 2 Mar 2017 05:13:24 +0000 (23:13 -0600)]
target: allow ALUA setup for some passthrough backends
This patch allows passthrough backends to use the core/base LIO
ALUA setup and state checks, but still handle the execution of
commands.
This will allow the target_core_user module to execute STPG and RTPG
in userspace, and not have to duplicate the ALUA state checks, path
information (needed so we can check if command is executable on
specific paths) and setup (rtslib sets/updates the configfs ALUA
interface like it does for iblock or file).
For STPG, the target_core_user userspace daemon, tcmu-runner will
still execute the STPG, and to update the core/base LIO state it
will use the existing configfs interface. For RTPG, tcmu-runner
will loop over configfs and/or cache the state.
Signed-off-by: Mike Christie <mchristi@redhat.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Mike Christie [Thu, 2 Mar 2017 05:14:39 +0000 (23:14 -0600)]
tcmu: allow hw_max_sectors greater than 128
tcmu hard codes the hw_max_sectors to 128 which is a litle small.
Userspace uses the max_sectors to report the optimal IO size and
some initiators perform better with larger IOs (open-iscsi seems
to do better with 256 to 512 depending on the test).
(Fix do not display hw max sectors twice - MNC)
Signed-off-by: Mike Christie <mchristi@redhat.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
All in-tree fabric drivers provide a tfo->check_stop_free(),
so there is no need to do the extra check within existing
transport_cmd_check_stop_to_fabric() code.
Just to be sure, add a check in target_fabric_tf_ops_check()
to notify any out-of-tree drivers that might be missing it.
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Helge Deller [Sat, 18 Mar 2017 16:13:27 +0000 (17:13 +0100)]
parisc: Fix system shutdown halt
On those parisc machines which don't provide a software power off
function, the system currently kills the init process at the end of a
shutdown and unexpectedly restarts insteads of halting.
Fix it by adding a loop which will not return.
Linus Torvalds [Sat, 18 Mar 2017 15:33:44 +0000 (08:33 -0700)]
Merge branch 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull CPU hotplug fix from Thomas Gleixner:
"A single fix preventing the concurrent execution of the CPU hotplug
callback install/invocation machinery. Long standing bug caused by a
massive brain slip of that Gleixner dude, which went unnoticed for
almost a year"
* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
cpu/hotplug: Serialize callback invocations proper
Linus Torvalds [Sat, 18 Mar 2017 00:25:14 +0000 (17:25 -0700)]
Merge tag 'pm-4.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
"These fix a few more intel_pstate issues and one small issue in the
cpufreq core.
Specifics:
- Fix breakage in the intel_pstate's debugfs interface for PID
controller tuning (Rafael Wysocki)
- Fix computations related to P-state limits in intel_pstate to avoid
excessive rounding errors leading to visible inaccuracies (Srinivas
Pandruvada, Rafael Wysocki)
- Add a missing newline to a message printed by one function in the
cpufreq core and clean up that function (Rafael Wysocki)"
* tag 'pm-4.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
cpufreq: Fix and clean up show_cpuinfo_cur_freq()
cpufreq: intel_pstate: Avoid percentages in limits-related computations
cpufreq: intel_pstate: Correct frequency setting in the HWP mode
cpufreq: intel_pstate: Update pid_params.sample_rate_ns in pid_param_set()
Merge branches 'pm-cpufreq-fixes' and 'intel_pstate-fixes'
* pm-cpufreq-fixes:
cpufreq: Fix and clean up show_cpuinfo_cur_freq()
* intel_pstate-fixes:
cpufreq: intel_pstate: Avoid percentages in limits-related computations
cpufreq: intel_pstate: Correct frequency setting in the HWP mode
cpufreq: intel_pstate: Update pid_params.sample_rate_ns in pid_param_set()
Linus Torvalds [Fri, 17 Mar 2017 21:16:22 +0000 (14:16 -0700)]
Merge tag 'nfs-for-4.11-2' of git://git.linux-nfs.org/projects/anna/linux-nfs
Pull NFS client fixes from Anna Schumaker:
"We have a handful of stable fixes to fix kernel warnings and other
bugs that have been around for a while. We've also found a few other
reference counting bugs and memory leaks since the initial 4.11 pull.
Stable Bugfixes:
- Fix decrementing nrequests in NFS v4.2 COPY to fix kernel warnings
- Prevent a double free in async nfs4_exchange_id()
- Squelch a kbuild sparse complaint for xprtrdma
Other Bugfixes:
- Fix a typo (NFS_ATTR_FATTR_GROUP_NAME) that causes a memory leak
- Fix a reference leak that causes kernel warnings
- Make nfs4_cb_sv_ops static to fix a sparse warning
- Respect a server's max size in CREATE_SESSION
- Handle errors from nfs4_pnfs_ds_connect
- Flexfiles layout shouldn't mark devices as unavailable"
* tag 'nfs-for-4.11-2' of git://git.linux-nfs.org/projects/anna/linux-nfs:
pNFS/flexfiles: never nfs4_mark_deviceid_unavailable
pNFS: return status from nfs4_pnfs_ds_connect
NFSv4.1 respect server's max size in CREATE_SESSION
NFS prevent double free in async nfs4_exchange_id
nfs: make nfs4_cb_sv_ops static
xprtrdma: Squelch kbuild sparse complaint
NFS: fix the fault nrequests decreasing for nfs_inode COPY
NFSv4: fix a reference leak caused WARNING messages
nfs4: fix a typo of NFS_ATTR_FATTR_GROUP_NAME
Linus Torvalds [Fri, 17 Mar 2017 21:05:03 +0000 (14:05 -0700)]
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
"An assorted pile of fixes along with some hardware enablement:
- a fix for a KASAN / branch profiling related boot failure
- some more fallout of the PUD rework
- a fix for the Always Running Timer which is not initialized when
the TSC frequency is known at boot time (via MSR/CPUID)
- a resource leak fix for the RDT filesystem
- another unwinder corner case fixup
- removal of the warning for duplicate NMI handlers because there are
legitimate cases where more than one handler can be registered at
the last level
- make a function static - found by sparse
- a set of updates for the Intel MID platform which got delayed due
to merge ordering constraints. It's hardware enablement for a non
mainstream platform, so there is no risk"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mpx: Make unnecessarily global function static
x86/intel_rdt: Put group node in rdtgroup_kn_unlock
x86/unwind: Fix last frame check for aligned function stacks
mm, x86: Fix native_pud_clear build error
x86/kasan: Fix boot with KASAN=y and PROFILE_ANNOTATED_BRANCHES=y
x86/platform/intel-mid: Add power button support for Merrifield
x86/platform/intel-mid: Use common power off sequence
x86/platform: Remove warning message for duplicate NMI handlers
x86/tsc: Fix ART for TSC_KNOWN_FREQ
x86/platform/intel-mid: Correct MSI IRQ line for watchdog device
Linus Torvalds [Fri, 17 Mar 2017 21:01:40 +0000 (14:01 -0700)]
Merge branch 'x86-acpi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 acpi fixes from Thomas Gleixner:
"This update deals with the fallout of the recent work to make
cpuid/node mappings persistent.
It turned out that the boot time ACPI based mapping tripped over ACPI
inconsistencies and caused regressions. It's partially reverted and
the fragile part replaced by an implementation which makes the mapping
persistent when a CPU goes online for the first time"
* 'x86-acpi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
acpi/processor: Check for duplicate processor ids at hotplug time
acpi/processor: Implement DEVICE operator for processor enumeration
x86/acpi: Restore the order of CPU IDs
Revert"x86/acpi: Enable MADT APIs to return disabled apicids"
Revert "x86/acpi: Set persistent cpuid <-> nodeid mapping when booting"
Linus Torvalds [Fri, 17 Mar 2017 20:19:07 +0000 (13:19 -0700)]
Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Thomas Gleixner:
"From the scheduler departement:
- a bunch of sched deadline related fixes which deal with various
buglets and corner cases.
- two fixes for the loadavg spikes which are caused by the delayed
NOHZ accounting"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/deadline: Use deadline instead of period when calculating overflow
sched/deadline: Throttle a constrained deadline task activated after the deadline
sched/deadline: Make sure the replenishment timer fires in the next period
sched/loadavg: Use {READ,WRITE}_ONCE() for sample window
sched/loadavg: Avoid loadavg spikes caused by delayed NO_HZ accounting
sched/deadline: Add missing update_rq_clock() in dl_task_timer()
Linus Torvalds [Fri, 17 Mar 2017 20:13:35 +0000 (13:13 -0700)]
Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fix from Thomas Gleixner:
"Just a simple revert of a new sched_clock implementation which turned
out to be buggy"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Revert "clocksource/drivers/tcb_clksrc: Use 32 bit tcb as sched_clock"
The nfs4_pnfs_ds_connect path can call rpc_create which can fail or it
can wait on another context to reach the same failure.
This checks that the rpc_create succeeded and returns the error to the
caller.
When an error is returned, both the files and flexfiles layouts will return
NULL from _prepare_ds(). The flexfiles layout will also return the layout
with the error NFS4ERR_NXIO.
Signed-off-by: Weston Andros Adamson <dros@primarydata.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
projects / karo-tx-linux.git / log