Impact: fix boot tracer + sched tracer coupling bug
Fix a bug that made the sched_switch tracer unable to run
if set as the current_tracer after the boot tracer.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
This patch applies some corrections suggested by Steven Rostedt.
Change the type of shed_ref into int since it is used
into a Mutex, we don't need it anymore as an atomic
variable in the sched_switch tracer.
Also change the name of the register mutex.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: enhance boot trace output with scheduling events
Use the sched_switch tracer from the boot tracer.
We also can trace schedule events inside the initcalls.
Sched tracing is disabled after the initcall has finished and
then reenabled before the next one is started.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
When init_sched_switch_trace() is called, it has no reason to start
the sched tracer if the sched_ref is not zero.
_ If this is non-zero, the tracer is already used, but we can register it
to the tracing engine. There is already a security which avoid the tracer
probes not to be resgistered twice.
_ If this is zero, this block will not be used.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix race condition in sched_switch tracer
This patch fixes a race condition in the sched_switch tracer. If
several tasks (IE: concurrent initcalls) are playing with
tracing_start_cmdline_record() and tracing_stop_cmdline_record(), the
following situation could happen:
_ Task A and B are using the same tracepoint probe. Task A holds it.
Task B is sleeping and doesn't hold it.
_ Task A frees the sched tracer, then sched_ref is decremented to 0.
_ Task A is preempted and hadn't yet unregistered its tracepoint
probe, then B runs.
_ B increments sched_ref, sees it's 1 and then guess it has to
register its probe. But it has not been freed by task A.
_ A lot of bad things can happen after that...
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: modify boot tracer
We used to disable the initcall tracing at a specified time (IE: end
of builtin initcalls). But we don't need it anymore. It will be
stopped when initcalls are finished.
However we want two things:
_Start this tracing only after pre-smp initcalls are finished.
_Since we are planning to trace sched_switches at the same time, we
want to enable them only during the initcall execution.
For this purpose, this patch introduce two functions to enable/disable
the sched_switch tracing during boot.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Use an event thread per-radio controller so processing events from one
radio controller doesn't delay another.
A radio controller shouldn't have information on devices seen by a
different radio controller (they may be on different channels) so make the
beacon cache per-radio controller.
Signed-off-by: Stefano Panella <stefano.panella@csr.com>
Signed-off-by: David Vrabel <david.vrabel@csr.com>
Add the commands UWB_DBG_CMD_IE_ADD and UWB_DBG_CMD_IE_RM to the debug
interface and make them call uwb_rc_ie_add() and uwb_rc_ie_rm().
Signed-off-by: Stefano Panella <stefano.panella@csr.com>
Signed-off-by: David Vrabel <david.vrabel@csr.com>
The structures and event handler needed to handle Relinish Request IEs
received from neighbors. Nothing is done with these IEs yet.
Signed-off-by: Stefano Panella <stefano.panella@csr.com>
Signed-off-by: David Vrabel <david.vrabel@csr.com>
2.6.28-rc tightened up the ELF architecture checks on ARM. For
non-EABI it only allows VFP if the hardware supports it. However,
the kernel fails to also inspect the soft-float flag, so it
incorrectly rejects binaries using soft-VFP.
The fix is simple: also check that EF_ARM_SOFT_FLOAT isn't set
before rejecting VFP binaries on non-VFP hardware.
Acked-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
In net/ipv4/netfilter/nf_nat_rule.c, the function warn_if_extra_mangle was added
in commit 5b1158e909 (2006-12-02). I have a DNAT
target in the OUTPUT chain than changes connections with dst 2.0.0.1 to another
address which I'll substitute with 66.102.9.99 below.
On every boot I get the following message:
[ 146.252505] NAT: no longer support implicit source local NAT
[ 146.252517] NAT: packet src 66.102.9.99 -> dst 2.0.0.1
As far as I can tell from reading the function doing this, it should warn if the
source IP for the route to 66.102.9.99 is different from 2.0.0.1 but that is not
the case. It doesn't make sense to check the DNAT target against the local route
source.
Either the function should be changed to correctly check the route, or it should
be removed entirely as it's been nearly 2 years since it was added.
Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Now that ebt_unregister_table() can be called during netns stop, and module
pinning scheme can't prevent netns stop, do table cleanup by hand.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
* return ebt_table from ebt_register_table(), module code will save it into
per-netns data for unregistration
* duplicate ebt_table at the very beginning of registration -- it's added into
list, so one ebt_table wouldn't end up in many lists (and each netns has
different one)
* introduce underscored tables in individial modules, this is temporary to not
break bisection.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
* propagate netns from userspace, register table in passed netns
* remporarily register every ebt_table in init_net
P. S.: one needs to add ".netns_ok = 1" to igmp_protocol to test with
ebtables(8) in netns.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This patch modifies xt_NFLOG to suppress the call to nf_log_packet()
function. The call of this wrapper in xt_NFLOG was causing NFLOG to
use the first initialized module. Thus, if ipt_ULOG is loaded before
nfnetlink_log all NFLOG rules are treated as plain LOG rules.
Signed-off-by: Eric Leblond <eric@inl.fr>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Impact: fix sysctl name typo
Steve must have needed more coffee ;-)
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: add SysRq-z support to dump trace buffers
Allows one to force an ftrace dump from sysrq
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: do not do function-tracing in the early-printk code
this is useful when earlyprintk=vga,keep is used to debug tracer
plugins.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup, add debug check
It's wrong to make dattr_new = NULL if doms_new == NULL, it introduces
memory leak if dattr_new != NULL. Fortunately dattr_new is always NULL
in this case. So remove the code and add a sanity check.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
The sysctl has been unregistered by partition_sched_domains().
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
cfs->tg is initialized in init_tg_cfs_entry() with tg != NULL, and
will never be invalidated to NULL. And the underlying cgroup of a
valid task_group is always valid.
Same for rt->tg.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
Just use the newly introduced sd->name.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: Documentation update only
Update the version that the ftrace document was written for.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: Documentation update only
A lot of changes have gone into ftrace. This patch updates
the ftrace.txt document.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: disable interrupts during trace entry creation (as opposed to preempt)
To help with performance, I set the ftracer to not disable interrupts,
and only to disable preemption. If an interrupt occurred, it would not
be traced, because the function tracer protects itself from recursion.
This may be faster, but the trace output might miss some traces.
This patch makes the fuction trace disable interrupts, but it also
adds a runtime feature to disable preemption instead. It does this by
having two different tracer functions. When the function tracer is
enabled, it will check to see which version is requested (irqs disabled
or preemption disabled). Then it will use the corresponding function
as the tracer.
Irq disabling is the default behaviour, but if the user wants better
performance, with the chance of missing traces, then they can choose
the preempt disabled version.
Running hackbench 3 times with the irqs disabled and 3 times with
the preempt disabled function tracer yielded:
tracing type times entries recorded
------------ -------- ----------------
irq disabled 43.393 166433066
43.282 166172618
43.298 166256704
preempt disabled 38.969 159871710
38.943 159972935
39.325 161056510
Average:
irqs disabled: 43.324 166287462
preempt disabled: 39.079 160300385
preempt is 10.8 percent faster than irqs disabled.
I wrote a patch to count function trace recursion and reran hackbench.
With irq disabled: 1,150 times the function tracer did not trace due to
recursion.
with preempt disabled: 5,117,718 times.
The thousand times with irq disabled could be due to NMIs, or simply a case
where it called a function that was not protected by notrace.
But we also see that a large amount of the trace is lost with the
preempt version.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: use new, consolidated APIs in ftrace plugins
This patch replaces the schedule safe preempt disable code with the
ftrace_preempt_disable() and ftrace_preempt_enable() safe functions.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: add new ftrace-plugin internal APIs
Parts of the tracer needs to be careful about schedule recursion.
If the NEED_RESCHED flag is set, a preempt_enable will call schedule.
Inside the schedule function, the NEED_RESCHED flag is cleared.
The problem arises when a trace happens in the schedule function but before
NEED_RESCHED is cleared. The race is as follows:
schedule()
>> tracer called
trace_function()
preempt_disable()
[ record trace ]
preempt_enable() <<- here's the issue.
[check NEED_RESCHED]
schedule()
[ Repeat the above, over and over again ]
The naive approach is simply to use preempt_enable_no_schedule instead.
The problem with that approach is that, although we solve the schedule
recursion issue, we now might lose a preemption check when not in the
schedule function.
trace_function()
preempt_disable()
[ record trace ]
[Interrupt comes in and sets NEED_RESCHED]
preempt_enable_no_resched()
[continue without scheduling]
The way ftrace handles this problem is with the following approach:
int resched;
resched = need_resched();
preempt_disable_notrace();
[record trace]
if (resched)
preempt_enable_no_sched_notrace();
else
preempt_enable_notrace();
This may seem like the opposite of what we want. If resched is set
then we call the "no_sched" version?? The reason we do this is because
if NEED_RESCHED is set before we disable preemption, there's two reasons
for that:
1) we are in an atomic code path
2) we are already on our way to the schedule function, and maybe even
in the schedule function, but have yet to clear the flag.
Both the above cases we do not want to schedule.
This solution has already been implemented within the ftrace infrastructure.
But the problem is that it has been implemented several times. This patch
encapsulates this code to two nice functions.
resched = ftrace_preempt_disable();
[ record trace]
ftrace_preempt_enable(resched);
This way the tracers do not need to worry about getting it right.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix udelay when "notsc" boot parameter is passed
With notsc passed on commandline, tsc may not be used for
udelays, make sure that we do not use tsc_khz to calculate
the lpj value in such cases.
Reported-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Alok N Kataria <akataria@vmware.com>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add NULL-check of the return value of snd_kctl_new1() before
accessing it. Also, make a sanity NULL check to snd_BUG_ON()
for debugging only.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Call device_create_file only once in snd_soc_dapm_sys_add function.
Signed-off-by: Troy Kisky <troy.kisky@boundarydevices.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
libata restores SControl on detach; however, trying to restore
non-zero DET can cause undeterministic behavior including PMP device
going offline till power cycling. Mask off DET when restoring
SControl.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
libata always uses PIO for ATAPI commands when the number of bytes to
transfer isn't multiple of 16 but quantum DAT72 chokes on odd bytes
PIO transfers. Implement a horkage to skip the mod16 check and apply
it to the quantum device.
This is reported by John Clark in the following thread.
http://thread.gmane.org/gmane.linux.ide/34748
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: John Clark <clarkjc@runbox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Peter Moulder has pointed out that there is a slight chance that a
negative value might be passed to jiffies_to_msecs() in
ata_scsi_park_show(). This is fixed by saving the value of jiffies in a
local variable, thus also reducing code since the volatile variable
jiffies is accessed only once.
Signed-off-by: Elias Oltmanns <eo@nebensachen.de>
Signed-off-by: Tejun Heo <tj.kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
All three flavors of sata_nv's are different in how their hardreset
behaves.
* generic: Hardreset is not reliable. Link often doesn't come online
after hardreset.
* nf2/3: A little bit better - link comes online with longer debounce
timing. However, nf2/3 can't reliable wait for the first D2H
Register FIS, so it can't wait for device readiness or classify the
device after hardreset. Follow-up SRST required.
* ck804: Hardreset finally works.
The core layer change to prefer hardreset and follow up changes
exposed the above issues and caused various detection regressions for
all three flavors. This patch, hopefully, fixes all the known issues
and should make sata_nv error handling more reliable.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
commit b9d5b89b48 (sata_via: fix support
for 5287) accidently (?) removed vt*_prepare_host error handling - restore it
catched by gcc:
drivers/ata/sata_via.c: In function 'svia_init_one':
drivers/ata/sata_via.c:567: warning: 'host' may be used uninitialized in this function
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Joseph Chan <JosephChan@via.com.tw>
Cc: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Promise ATA engines need to be reset when errors occur.
That's currently done for errors detected by sata_promise itself,
but it's not done for errors like timeouts detected outside of
the low-level driver.
The effect of this omission is that a timeout tends to result
in a sequence of failed COMRESETs after which libata EH gives
up and disables the port. At that point the port's ATA engine
hangs and even reloading the driver will not resume it.
To fix this, make sata_promise override ->hardreset on SATA
ports with code which calls pdc_reset_port() on the port in
question before calling libata's hardreset. PATA ports don't
use ->hardreset, so for those we override ->softreset instead.
Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
The generic packet receive code takes care of setting
netdev->last_rx when necessary, for the sake of the
bonding ARP monitor.
Signed-off-by: David S. Miller <davem@davemloft.net>
All these individual parsing functions never return an error,
so they can be void.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The generic packet receive code takes care of setting
netdev->last_rx when necessary, for the sake of the
bonding ARP monitor.
Drivers need not do it any more.
Some cases had to be skipped over because the drivers
were making use of the ->last_rx value themselves.
Signed-off-by: David S. Miller <davem@davemloft.net>
max_state is unsigned long.
don't set max_state a negative value
Cc : Thomas Sujith <sujith.thomas@intel.com>
Cc : Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
From: Alexey Dobriyan <adobriyan@gmail.com>
Based upon a lockdep trace by Simon Arlott.
xfrm_policy_kill() can be called from both BH and
non-BH contexts, so we have to grab xfrm_policy_gc_lock
with BH disabling.
Signed-off-by: David S. Miller <davem@davemloft.net>
