To allow constant folding in msecs_to_jiffies() conditionally calls
the HZ dependent _msecs_to_jiffies() helpers or, when gcc can not
figure out constant folding, __msecs_to_jiffies which is the renamed
original msecs_to_jiffies() function.
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Cc: Masahiro Yamada <yamada.m@jp.panasonic.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Joe Perches <joe@perches.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Andrew Hunter <ahh@google.com> Cc: Paul Turner <pjt@google.com> Cc: Michal Marek <mmarek@suse.cz> Link: http://lkml.kernel.org/r/1431951554-5563-3-git-send-email-hofrat@osadl.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Refactor the msecs_to_jiffies conditional code part in time.c and
jiffies.h putting it into conditional functions rather than #ifdefs
to improve readability.
[ tglx: Verified that there is no binary code change ]
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Cc: Masahiro Yamada <yamada.m@jp.panasonic.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Joe Perches <joe@perches.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Andrew Hunter <ahh@google.com> Cc: Paul Turner <pjt@google.com> Cc: Michal Marek <mmarek@suse.cz> Link: http://lkml.kernel.org/r/1431951554-5563-2-git-send-email-hofrat@osadl.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
kernel/time/timeconst.h is moved to include/generated/ and generated
by the top level Kbuild. This allows using timeconst.h in an earlier
build stage.
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Cc: Masahiro Yamada <yamada.m@jp.panasonic.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Joe Perches <joe@perches.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Andrew Hunter <ahh@google.com> Cc: Paul Turner <pjt@google.com> Cc: Michal Marek <mmarek@suse.cz> Link: http://lkml.kernel.org/r/1431951554-5563-1-git-send-email-hofrat@osadl.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Peter Zijlstra [Thu, 14 May 2015 10:23:11 +0000 (12:23 +0200)]
sched,perf: Fix periodic timers
In the below two commits (see Fixes) we have periodic timers that can
stop themselves when they're no longer required, but need to be
(re)-started when their idle condition changes.
Further complications is that we want the timer handler to always do
the forward such that it will always correctly deal with the overruns,
and we do not want to race such that the handler has already decided
to stop, but the (external) restart sees the timer still active and we
end up with a 'lost' timer.
The problem with the current code is that the re-start can come before
the callback does the forward, at which point the forward from the
callback will WARN about forwarding an enqueued timer.
Now, conceptually its easy to detect if you're before or after the fwd
by comparing the expiration time against the current time. Of course,
that's expensive (and racy) because we don't have the current time.
Alternatively one could cache this state inside the timer, but then
everybody pays the overhead of maintaining this extra state, and that
is undesired.
The only other option that I could see is the external timer_active
variable, which I tried to kill before. I would love a nicer interface
for this seemingly simple 'problem' but alas.
Thomas Gleixner [Thu, 7 May 2015 12:35:59 +0000 (14:35 +0200)]
nohz: Fix !HIGH_RES_TIMERS hang
Simon Horman reported this crash on a system with
high-res timers disabled but nohz enabled:
> ------------[ cut here ]------------
> kernel BUG at kernel/irq_work.c:135!
BUG_ON(!irqs_disabled());
So something enabled interrupts in the periodic tick handling machinery,
and that code path indeed has a local_irq_disable()/enable pair in
tick_nohz_switch_to_nohz() which causes havoc. Fix it.
This patch also fixes a +nohz -hrtimers hang reported by Ingo Molnar.
Reported-by: Simon Horman <horms@verge.net.au> Reported-by: Ingo Molnar <mingo@kernel.org> Tested-by: Simon Horman <horms@verge.net.au> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: LAK <linux-arm-kernel@lists.infradead.org> Cc: Magnus Damm <magnus.damm@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1505071425520.4225@nanos Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andreas Sandberg [Fri, 24 Apr 2015 13:06:05 +0000 (13:06 +0000)]
tick: hrtimer-broadcast: Prevent endless restarting when broadcast device is unused
The hrtimer callback in the hrtimer's tick broadcast code sometimes
incorrectly ends up scheduling events at the current tick causing the
kernel to hang servicing the same hrtimer forever. This typically
happens when a device is swapped out by
tick_install_broadcast_device(), which replaces the event handler with
clock_events_handle_noop() and sets the device mode to
CLOCK_EVT_MODE_UNUSED. If the timer is scheduled when this happens,
the next_event field will not be updated and the hrtimer ends up being
restarted at the current tick. To prevent this from happening, only
try to restart the hrtimer if the broadcast clock event device is in
one of the active modes and try to cancel the timer when entering the
CLOCK_EVT_MODE_UNUSED mode.
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com> Tested-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/1429880765-5558-1-git-send-email-andreas.sandberg@arm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Joonwoo Park [Tue, 28 Apr 2015 02:21:49 +0000 (19:21 -0700)]
timer: Use timer->base for flag checks
At present, internal_add_timer() examines flags with 'base' which doesn't
contain flags. Examine with 'timer->base' to avoid unnecessary waking up
of nohz CPU when timer base has TIMER_DEFERRABLE set.
tick-broadcast: Fix the printing of broadcast masks
Today the number of bits of the broadcast masks that is output into
/proc/timer_list is sizeof(unsigned long). This means that on machines
with a larger number of CPUs, the bitmasks of CPUs beyond this range do
not appear.
Fix this by using bitmap printing through "%*pb" instead, so as to
output the broadcast masks for the range of nr_cpu_ids into
/proc/timer_list.
Thomas Gleixner [Tue, 5 May 2015 07:44:24 +0000 (09:44 +0200)]
tick: broadcast: Simplify oneshot logic and shorten lock region
Simplify the oneshot logic by avoiding the reprogramming loops. That
also allows to call the cpu local handler outside of the
broadcast_lock held region.
Tested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Thomas Gleixner [Tue, 5 May 2015 08:00:13 +0000 (10:00 +0200)]
tick: broadcast: Prevent livelock from event handler
With the removal of the hrtimer softirq the switch to highres/nohz
mode happens in the tick interrupt. That leads to a livelock when the
per cpu event handler is directly called from the broadcast handler
under broadcast lock because broadcast lock needs to be taken for the
highres/nohz switch as well.
Solve this by calling the cpu local handler outside the broadcast_lock
held region.
Fixes: c6eb3f70d448 "hrtimer: Get rid of hrtimer softirq" Reported-and-tested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Peter Zijlstra [Wed, 15 Apr 2015 09:41:58 +0000 (11:41 +0200)]
perf: Fix mux_interval hrtimer wreckage
Thomas stumbled over the hrtimer_forward_now() in
perf_event_mux_interval_ms_store() and noticed its broken-ness.
You cannot just change the expiry time of an active timer, it will
destroy the red-black tree order and cause havoc.
Change it to (re)start the timer instead, (re)starting a timer will
dequeue and enqueue a timer and therefore preserve rb-tree order.
Since we cannot enqueue remotely, wrap the thing in
cpu_function_call(), this however mandates that we restrict ourselves
to online cpus. Also serialize the entire setting so we don't get
multiple concurrent threads trying to update to different values.
Also fix a problem in perf_mux_hrtimer_restart(), checking against
hrtimer_active() can actually loose us the timer when timer->state ==
HRTIMER_STATE_CALLBACK and the callback has already decided NORESTART.
Furthermore it doesn't make any sense to test
hrtimer_callback_running() when we already tested hrtimer_active(),
but with the above change, we explicitly must call it when
callback_running.
Lastly, rename a few functions:
s/perf_cpu_hrtimer_/perf_mux_hrtimer_/ -- because I could not find
the mux timer function
s/\<hr\>/timer/ -- because that's the normal way of calling things.
Fixes: 62b856397927 ("perf: Add sysfs entry to adjust multiplexing interval per PMU") Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: http://lkml.kernel.org/r/20150415095011.863052571@infradead.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Peter Zijlstra [Wed, 15 Apr 2015 09:41:57 +0000 (11:41 +0200)]
sched: Cleanup bandwidth timers
Roman reported a 3 cpu lockup scenario involving __start_cfs_bandwidth().
The more I look at that code the more I'm convinced its crack, that
entire __start_cfs_bandwidth() thing is brain melting, we don't need to
cancel a timer before starting it, *hrtimer_start*() will happily remove
the timer for you if its still enqueued.
Removing that, removes a big part of the problem, no more ugly cancel
loop to get stuck in.
So now, if I understand things right, the entire reason you have this
cfs_b->lock guarded ->timer_active nonsense is to make sure we don't
accidentally lose the timer.
It appears to me that it should be possible to guarantee that same by
unconditionally (re)starting the timer when !queued. Because regardless
what hrtimer::function will return, if we beat it to (re)enqueue the
timer, it doesn't matter.
Now, because hrtimers don't come with any serialization guarantees we
must ensure both handler and (re)start loop serialize their access to
the hrtimer to avoid both trying to forward the timer at the same
time.
Update the rt bandwidth timer to match.
This effectively reverts: 09dc4ab03936 ("sched/fair: Fix
tg_set_cfs_bandwidth() deadlock on rq->lock").
Reported-by: Roman Gushchin <klamm@yandex-team.ru> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Ben Segall <bsegall@google.com> Cc: Paul Turner <pjt@google.com> Link: http://lkml.kernel.org/r/20150415095011.804589208@infradead.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Peter Zijlstra [Tue, 20 May 2014 13:49:48 +0000 (15:49 +0200)]
hrtimer: Allow concurrent hrtimer_start() for self restarting timers
Because we drop cpu_base->lock around calling hrtimer::function, it is
possible for hrtimer_start() to come in between and enqueue the timer.
If hrtimer::function then returns HRTIMER_RESTART we'll hit the BUG_ON
because HRTIMER_STATE_ENQUEUED will be set.
Since the above is a perfectly valid scenario, remove the BUG_ON and
make the enqueue_hrtimer() call conditional on the timer not being
enqueued already.
NOTE: in that concurrent scenario its entirely common for both sites
to want to modify the hrtimer, since hrtimers don't provide
serialization themselves be sure to provide some such that the
hrtimer::function and the hrtimer_start() caller don't both try and
fudge the expiration state at the same time.
To that effect, add a WARN when someone tries to forward an already
enqueued timer, the most common way to change the expiry of self
restarting timers. Ideally we'd put the WARN in everything modifying
the expiry but most of that is inlines and we don't need the bloat.
Fixes: 2d44ae4d7135 ("hrtimer: clean up cpu->base locking tricks") Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Ben Segall <bsegall@google.com> Cc: Roman Gushchin <klamm@yandex-team.ru> Cc: Paul Turner <pjt@google.com> Link: http://lkml.kernel.org/r/20150415113105.GT5029@twins.programming.kicks-ass.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Thomas Gleixner [Tue, 14 Apr 2015 21:09:25 +0000 (21:09 +0000)]
hrtimer: Avoid locking in hrtimer_cancel() if timer not active
We can do a lockless check for hrtimer_active before actually taking
the lock in hrtimer[_try_to]_cancel. This is useful for hotpath users
like nanosleep as they avoid the lock dance when the timer has
expired.
This is safe because active is true when the timer is enqueued or the
callback is running. Taking the hrtimer base lock does not protect
against concurrent hrtimer_start calls, the callsite has to do the
proper serialization itself.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/r/20150414203503.580273114@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Thomas Gleixner [Tue, 14 Apr 2015 21:09:22 +0000 (21:09 +0000)]
tick: broadcast-hrtimer: Remove overly clever return value abuse
The assignment of bc_moved in the conditional construct relies on the
fact that in the case of hrtimer_start() invocation the return value
is always 0. It took me a while to understand it.
We want to get rid of the hrtimer_start() return value. Open code the
logic which makes it readable as well.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/r/20150414203503.404751457@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The check for hrtimer_active() after starting the timer is
pointless. If the timer is inactive it has expired already and
therefor the task pointer is already NULL.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: David S. Miller <davem@davemloft.net> Link: http://lkml.kernel.org/r/20150414203503.165258315@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Thomas Gleixner [Tue, 14 Apr 2015 21:09:15 +0000 (21:09 +0000)]
rtmutex: Remove bogus hrtimer_active() check
The check for hrtimer_active() after starting the timer is
pointless. If the timer is inactive it has expired already and
therefor the task pointer is already NULL.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/r/20150414203503.081830481@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Thomas Gleixner [Tue, 14 Apr 2015 21:09:13 +0000 (21:09 +0000)]
futex: Remove bogus hrtimer_active() check
The check for hrtimer_active() after starting the timer is
pointless. If the timer is inactive it has expired already and
therefor the task pointer is already NULL.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/r/20150414203502.985825453@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Thomas Gleixner [Tue, 14 Apr 2015 21:09:11 +0000 (21:09 +0000)]
hrtimer: Remove bogus hrtimer_active() check
The check for hrtimer_active() after starting the timer is
pointless. If the timer is inactive it has expired already and
therefor the task pointer is already NULL.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/r/20150414203502.907149271@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Thomas Gleixner [Tue, 14 Apr 2015 21:08:58 +0000 (21:08 +0000)]
tick: Nohz: Rework next timer evaluation
The evaluation of the next timer in the nohz code is based on jiffies
while all the tick internals are nano seconds based. We have also to
convert hrtimer nanoseconds to jiffies in the !highres case. That's
just wrong and introduces interesting corner cases.
Turn it around and convert the next timer wheel timer expiry and the
rcu event to clock monotonic and base all calculations on
nanoseconds. That identifies the case where no timer is pending
clearly with an absolute expiry value of KTIME_MAX.
Makes the code more readable and gets rid of the jiffies magic in the
nohz code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Link: http://lkml.kernel.org/r/20150414203502.184198593@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Thomas Gleixner [Tue, 14 Apr 2015 21:08:54 +0000 (21:08 +0000)]
tick: sched: Force tick interrupt and get rid of softirq magic
We already got rid of the hrtimer reprogramming loops and hoops as
hrtimer now enforces an interrupt if the enqueued time is in the past.
Do the same for the nohz non highres mode. That gets rid of the need
to raise the softirq which only serves the purpose of getting the
machine out of the inner idle loop.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Link: http://lkml.kernel.org/r/20150414203502.023464878@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Thomas Gleixner [Tue, 14 Apr 2015 21:08:51 +0000 (21:08 +0000)]
hrtimer: Get rid of hrtimer softirq
hrtimer softirq is a leftover from the initial implementation and
serves only the purpose to handle the enqueueing of already expired
timers in the high resolution timer mode. We discussed whether we
change the return value and force all start sites to handle that the
timer is already expired, but that would be a Herculean task and I'm
not sure whether its a good idea to enforce that handling on
everyone.
A simpler solution is to enforce a timer interrupt instead of raising
and scheduling a softirq. Just use the existing infrastructure to do
so and remove all the softirq leftovers.
The HRTIMER softirq enum is now unused, but kept around because trace
parsers rely on the existing numbering.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/r/20150414203501.840834708@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Thomas Gleixner [Tue, 14 Apr 2015 21:08:49 +0000 (21:08 +0000)]
hrtimer: Keep pointer to first timer and simplify __remove_hrtimer()
__remove_hrtimer() needs to evaluate the expiry time to figure out
whether the timer which is removed is eventually the first expiring
timer on the cpu. Keep a pointer to it, which is lazily updated, so we
can avoid the evaluation dance and retrieve the information from there.
Generates slightly better code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/r/20150414203501.752838019@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Thomas Gleixner [Tue, 14 Apr 2015 21:08:46 +0000 (21:08 +0000)]
timerqueue: Let timerqueue_add/del return information
The hrtimer code is interested whether the added timer is the first
one to expire and whether the removed timer was the last one in the
tree. The add/del routines have that information already. So we can
return it right away instead of reevaluating it at the call site.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20150414203501.579063647@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Thomas Gleixner [Tue, 14 Apr 2015 21:08:44 +0000 (21:08 +0000)]
hrtimer: Align the hrtimer clock bases as well
We don't use cacheline_align here because that might waste lot of
space on 32bit machine with 64 bytes cachelines and on 64bit machines
with 128 bytes cachelines.
The size of struct hrtimer_clock_base is 64byte on 64bit and 32byte on
32bit machines. So we utilize the cache lines proper.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/r/20150414203501.498165771@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Thomas Gleixner [Tue, 14 Apr 2015 21:08:41 +0000 (21:08 +0000)]
hrtimer: Use cpu_base->active_base for hotpath iterators
The active_bases field is guaranteed to be in sync with the timerqueue
of the corresponding clock base. So we can use it for iterating over
the clock bases. This allows to break out early if no more active
clock bases are available and avoids touching the cache lines of
inactive clock bases.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/r/20150414203501.322887675@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Thomas Gleixner [Tue, 14 Apr 2015 21:08:37 +0000 (21:08 +0000)]
hrtimer: Make offset update smarter
On every tick/hrtimer interrupt we update the offset variables of the
clock bases. That's silly because these offsets change very seldom.
Add a sequence counter to the time keeping code which keeps track of
the offset updates (clock_was_set()). Have a sequence cache in the
hrtimer cpu bases to evaluate whether the offsets must be updated or
not. This allows us later to avoid pointless cacheline pollution.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20150414203501.132820245@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org>
Thomas Gleixner [Tue, 14 Apr 2015 21:08:35 +0000 (21:08 +0000)]
hrtimer: Get rid of softirq time
The softirq time field in the clock bases is an optimization from the
early days of hrtimers. It provides a coarse "jiffies" like time
mostly for self rearming timers.
But that comes with a price:
- Larger code size
- Extra storage space
- Duplicated functions with really small differences
The benefit of this is optimization is marginal for contemporary
systems.
Consolidate everything on the high resolution timer
implementation. This makes further optimizations possible.
Text size reduction:
x8664 -95, i386 -356, ARM -148, ARM64 -40, power64 -16
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/r/20150414203501.039977424@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Thomas Gleixner [Tue, 14 Apr 2015 21:08:30 +0000 (21:08 +0000)]
sound: Use hrtimer_resolution instead of hrtimer_get_res()
No point in converting a timespec now that the value is directly
accessible. Get rid of the null check while at it. Resolution is
guaranteed to be > 0.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Takashi Iwai <tiwai@suse.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jaroslav Kysela <perex@perex.cz> Cc: alsa-devel@alsa-project.org Link: http://lkml.kernel.org/r/20150414203500.799133359@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Thomas Gleixner [Tue, 14 Apr 2015 21:08:27 +0000 (21:08 +0000)]
hrtimer: Get rid of the resolution field in hrtimer_clock_base
The field has no value because all clock bases have the same
resolution. The resolution only changes when we switch to high
resolution timer mode. We can evaluate that from a single static
variable as well. In the !HIGHRES case its simply a constant.
Export the variable, so we can simplify the usage sites.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/r/20150414203500.645454122@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
hrtimer: Update active_bases before calling hrtimer_force_reprogram()
'active_bases' indicates which clock-base have active timer. The
intention of this bit field was to avoid evaluating inactive bases. It
was introduced with the introduction of the BOOTTIME and TAI clock
bases, but it was never brought into full use.
We want to use it now, but in __remove_hrtimer() the update happens
after the calling hrtimer_force_reprogram() which has to evaluate all
clock bases for the next expiring timer. So in case the last timer of
a clock base got removed we still see the active bit and therefor
evaluate the clock base for no value. There are further optimizations
possible when active_bases is updated in the right place.
Move the update before the call to hrtimer_force_reprogram()
Thomas Gleixner [Wed, 22 Apr 2015 09:44:15 +0000 (11:44 +0200)]
timekeeping: Remove stale function prototype
commit 61edec81d260 "timekeeping: Simplify timekeeping_clocktai()"
implemented timekeeping_clocktai() as an inline function, but left the
old extern prototype in the header file. Remove it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The function clocksource_get_next() was removed in commit 75c5158f70
(timekeeping: Update clocksource with stop_machine), but the
prototype was not removed with it. Remove the prototype.
Signed-off-by: Yingjoe Chen <yingjoe.chen@mediatek.com> Cc: <linux-arm-kernel@lists.infradead.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: <srv_heupstream@mediatek.com> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/1428674150-1780-1-git-send-email-yingjoe.chen@mediatek.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"I'd like to say these were a set of regressions for the recent merge
window code. Unfortunately, they all predate the merge window code
(stable cc'd).
There are two fixes for data integrity (mostly only showing up on
module removal), an mvsas crash with expander attached SATA devices
which goes back to the dawn of the driver but is only just being
picked up as sas expanders become a standard item in low end server
hardware, an am53c974 one because the interrupt data isn't fully
initialised before the line is and a megaraid_sas one because it uses
smp_processor_id() to select MSI-X queues and that now triggers a
WARN_ON()"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
mvsas: fix panic on expander attached SATA devices
am53c974: Fix crash during modprobe
megaraid_sas: use raw_smp_processor_id()
sd: Fix missing ATO tag check
sd: Unregister integrity profile
Merge branch 'drm-next-merged' of git://people.freedesktop.org/~airlied/linux
Pull drm updates from Dave Airlie:
"Highlights:
Core:
- Virtual GEM layer merged, this has been around for a long time, and
it provides a software backed device that allows userspace to use
it as a GEM shared memory handler. This makes it a lot easier to
do certain things when you have no GPU but still have to deal with
DRI expectations.
- atomic helper updates.
- framebuffer modifier interface added.
- i2c over auxch displayport fixes.
- fb width/height confusion fixes.
- new driver for ps8622/ps8625 bridge chips
- lots of new panels
i915:
- more plane atomic conversion
- vGPU guest support for XenGT
- Skylake workarounds and fixes
- Y-tiling support
- work on dynamic pagetable allocation
- EU count report param for gen9+
- CHV fixes (no longer prelim)
- remove ilk rc6
- frontbuffer tracking for fbc
- Displayport link rate refactoring
- sprite colorkey refactor
radeon:
- Displayport MST support (not enabled by default)
- non-ATOM native hw auxch support (DCE5+)
- output csc support
- new queries for userspace debug support
- new VCE packet
nouveau:
- gk20a iommu support
- gm107 graphics support
- more gm20x bringup (waiting on signed nvidia fw).
amdkfd:
- multiple kgd instance support
- use 64-bit time accessors
msm:
- stolen memory support
- DSI and dual-DSI support
- snapdragon 410 support
exynos:
- cleanups for atomic and pageflip
imx-drm:
- more media-bus formats
- TV output prep
- drm panel support
tegra:
- hw vblank counter using host1x syncpoints
omap:
- universal plane support
- prep work for atomic modesetting
rcar-du:
- ported to atomic modesetting
atmel-hlcdc:
- ported to atomic modesetting
- added suspend/resume support
sti:
- ported to atomic modesetting
dwhdmi:
- more compliant audio support
- update rockchip phy support
* 'drm-next-merged' of git://people.freedesktop.org/~airlied/linux: (689 commits)
media-bus: Fixup RGB444_1X12, RGB565_1X16, and YUV8_1X24 media bus format
drm/i915: Dont enable CS_PARSER_ERROR interrupts at all
drm/i915: Move drm_framebuffer_unreference out of struct_mutex for takeover
drm: fix trivial typo mistake
drm: Make integer overflow checking cover universal cursor updates (v2)
drm/nouveau/bios: fix fetching from acpi on certain systems
drm/nouveau/gr/gm206: initial init+ctx code
drm/nouveau/ce/gm206: enable support via gm204 code
drm/nouveau/fifo/gm206: enable support via gm204 code
drm/nouveau/gr/gm204: initial init+ctx code
drm/nouveau: support for buffer moves via MaxwellDmaCopyA
drm/nouveau/ce/gm204: initial support
drm/nouveau: add support for gm20x fifo channels
drm/nouveau/fifo/gm204: initial support
drm/nouveau/gr/gk104-: prevent reading non-existent regs in intr handler
drm/nouveau/gr/gm107: very slightly demagic part of attrib cb setup
drm/nouveau/gr/gk104-: correct crop/zrop num_active_fbps setting
drm/nouveau/gr/gf100-: add symbolic names for classes
drm/nouveau/gr/gm107: support tpc "strand" ctxsw in gpccs ucode
drm/nouveau/gr/gf100-: support mmio access with gpc offset from gpccs ucode
...
Merge tag 'iommu-updates-v4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU updates from Joerg Roedel:
"Not much this time, but the changes include:
- moving domain allocation into the iommu drivers to prepare for the
introduction of default domains for devices
- fixing the IO page-table code in the AMD IOMMU driver to correctly
encode large page sizes
- extension of the PCI support in the ARM-SMMU driver
- various fixes and cleanups"
* tag 'iommu-updates-v4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (34 commits)
iommu/amd: Correctly encode huge pages in iommu page tables
iommu/amd: Optimize amd_iommu_iova_to_phys for new fetch_pte interface
iommu/amd: Optimize alloc_new_range for new fetch_pte interface
iommu/amd: Optimize iommu_unmap_page for new fetch_pte interface
iommu/amd: Return the pte page-size in fetch_pte
iommu/amd: Add support for contiguous dma allocator
iommu/amd: Don't allocate with __GFP_ZERO in alloc_coherent
iommu/amd: Ignore BUS_NOTIFY_UNBOUND_DRIVER event
iommu/amd: Use BUS_NOTIFY_REMOVED_DEVICE
iommu/tegra: smmu: Compute PFN mask at runtime
iommu/tegra: gart: Set aperture at domain initialization time
iommu/tegra: Setup aperture
iommu: Remove domain_init and domain_free iommu_ops
iommu/fsl: Make use of domain_alloc and domain_free
iommu/rockchip: Make use of domain_alloc and domain_free
iommu/ipmmu-vmsa: Make use of domain_alloc and domain_free
iommu/shmobile: Make use of domain_alloc and domain_free
iommu/msm: Make use of domain_alloc and domain_free
iommu/tegra-gart: Make use of domain_alloc and domain_free
iommu/tegra-smmu: Make use of domain_alloc and domain_free
...
Merge tag 'cpumask-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull final removal of deprecated cpus_* cpumask functions from Rusty Russell:
"This is the final removal (after several years!) of the obsolete
cpus_* functions, prompted by their mis-use in staging.
With these function removed, all cpu functions should only iterate to
nr_cpu_ids, so we finally only allocate that many bits when cpumasks
are allocated offstack"
* tag 'cpumask-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (25 commits)
cpumask: remove __first_cpu / __next_cpu
cpumask: resurrect CPU_MASK_CPU0
linux/cpumask.h: add typechecking to cpumask_test_cpu
cpumask: only allocate nr_cpumask_bits.
Fix weird uses of num_online_cpus().
cpumask: remove deprecated functions.
mips: fix obsolete cpumask_of_cpu usage.
x86: fix more deprecated cpu function usage.
ia64: remove deprecated cpus_ usage.
powerpc: fix deprecated CPU_MASK_CPU0 usage.
CPU_MASK_ALL/CPU_MASK_NONE: remove from deprecated region.
staging/lustre/o2iblnd: Don't use cpus_weight
staging/lustre/libcfs: replace deprecated cpus_ calls with cpumask_
staging/lustre/ptlrpc: Do not use deprecated cpus_* functions
blackfin: fix up obsolete cpu function usage.
parisc: fix up obsolete cpu function usage.
tile: fix up obsolete cpu function usage.
arm64: fix up obsolete cpu function usage.
mips: fix up obsolete cpu function usage.
x86: fix up obsolete cpu function usage.
...
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull more s390 updates from Martin Schwidefsky:
"The big thing in this second merge for s390 is the new eBPF JIT from
Michael which replaces the old 32-bit backend.
The remaining commits are bug fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/pci: add locking for fmb access
s390/pci: extract software counters from fmb
s390/dasd: Fix unresumed device after suspend/resume having no paths
s390/dasd: fix unresumed device after suspend/resume
s390/dasd: fix inability to set a DASD device offline
s390/mm: Fix memory hotplug for unaligned standby memory
s390/bpf: Add s390x eBPF JIT compiler backend
s390: Use bool function return values of true/false not 1/0
Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu
Pull m68k fixes from Greg Ungerer:
"Nothing big, spelling fixes and fix/cleanup for ColdFire eth device setup"
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
m68knommu: fix fec setup warning for ColdFire 5271 builds
m68knommu: ColdFire 5271 only has a single FEC controller
m68k: Fix trivial typos in comments
Yes, it should work, but it's a bad idea. Not only did ARM64 not have
the 16-bit access code (there's a separate patch to add it), it's just
not a good atomic type. Some architectures fundamentally don't do
atomic accesses in them (alpha), and it's not like it saves any space
here anyway because of structure packing issues.
We normally should aim for flags to be "unsigned int" or "unsigned
long". And if space is at a premium, use a single byte (although that
causes problems on alpha again). There might be very special cases
where a 16-byte entity is really wanted, but this is not one of them.
OMAPDSS: Correct video ports description file path in DT binding doc
The doc refers to Documentation/devicetree/bindings/video/video-ports.txt
which does not exist. The documentation seems to be outdated and wants to
refer to Documentation/devicetree/bindings/graph.txt instead.
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Philipp Zabel [Fri, 17 Apr 2015 17:12:41 +0000 (19:12 +0200)]
media-bus: Fixup RGB444_1X12, RGB565_1X16, and YUV8_1X24 media bus format
Change the constant values for RGB444_1X12, RGB565_1X16, and YUV8_1X24 media
bus formats in anticipation of a merge conflict with the media tree, where
the old values are already taken by RBG888_1X24, RGB888_1X32_PADHI, and
VUY8_1X24, respectively.
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de> Signed-off-by: Dave Airlie <airlied@redhat.com>
Merge branch 'turbostat' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux
Pull turbostat update from Len Brown:
"Updates to the turbostat utility.
Just one kernel dependency in this batch -- added a #define to
msr-index.h"
* 'turbostat' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
tools/power turbostat: correct dumped pkg-cstate-limit value
tools/power turbostat: calculate TSC frequency from CPUID(0x15) on SKL
tools/power turbostat: correct DRAM RAPL units on recent Xeon processors
tools/power turbostat: Initial Skylake support
tools/power turbostat: Use $(CURDIR) instead of $(PWD) and add support for O= option in Makefile
tools/power turbostat: modprobe msr, if needed
tools/power turbostat: dump MSR_TURBO_RATIO_LIMIT2
tools/power turbostat: use new MSR_TURBO_RATIO_LIMIT names
x86 msr-index: define MSR_TURBO_RATIO_LIMIT,1,2
tools/power turbostat: label base frequency
tools/power turbostat: update PERF_LIMIT_REASONS decoding
tools/power turbostat: simplify default output
The test_data_1_le[] array is a const array of const char *. To avoid
dropping any const information, we need to use "const char * const *",
not just "const char **".
I'm not sure why the different test arrays end up having different
const'ness, but let's make the pointer we use to traverse them as const
as possible, since we modify neither the array of pointers _or_ the
pointers we find in the array.
smp: Fix error case handling in smp_call_function_*()
Commit 8053871d0f7f ("smp: Fix smp_call_function_single_async()
locking") fixed the locking for the asynchronous smp-call case, but in
the process of moving the lock handling around, one of the error cases
ended up not unlocking the call data at all.
This went unnoticed on x86, because this is a "caller is buggy" case,
where the caller is trying to call a non-existent CPU. But apparently
ARM does that (at least under qemu-arm). Bindly doing cross-cpu calls
to random CPU's that aren't even online seems a bit fishy, but the error
handling was clearly not correct.
Simply add the missing "csd_unlock()" to the error path.
Pull sparc fixes from David Miller
"Unfortunately, I brown paper bagged the generic iommu pool allocator
by applying the wrong revision of the patch series.
This reverts the bad one, and puts the right one in"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
iommu-common: Fix PARISC compile-time warnings
sparc: Make LDC use common iommu poll management functions
sparc: Make sparc64 use scalable lib/iommu-common.c functions
Break up monolithic iommu table/lock into finer graularity pools and lock
sparc: Revert generic IOMMU allocator.
Merge tag 'for-linus-4.1-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs
Pull 9pfs updates from Eric Van Hensbergen:
"Some accumulated cleanup patches for kerneldoc and unused variables as
well as some lock bug fixes and adding privateport option for RDMA"
* tag 'for-linus-4.1-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
net/9p: add a privport option for RDMA transport.
fs/9p: Initialize status in v9fs_file_do_lock.
net/9p: Initialize opts->privport as it should be.
net/9p: use memcpy() instead of snprintf() in p9_mount_tag_show()
9p: use unsigned integers for nwqid/count
9p: do not crash on unknown lock status code
9p: fix error handling in v9fs_file_do_lock
9p: remove unused variable in p9_fd_create()
9p: kerneldoc warning fixes
David S. Miller [Sat, 18 Apr 2015 19:35:09 +0000 (12:35 -0700)]
Merge branch 'iommu-generic-allocator'
Sowmini Varadhan says:
====================
Generic IOMMU pooled allocator
Investigation of network performance on Sparc shows a high
degree of locking contention in the IOMMU allocator, and it
was noticed that the PowerPC code has a better locking model.
This patch series tries to extract the generic parts of the
PowerPC code so that it can be shared across multiple PCI
devices and architectures.
v10: resend patchv9 without RFC tag, and a new mail Message-Id,
(previous non-RFC attempt did not show up on the patchwork queue?)
Full revision history below:
v2 changes:
- incorporate David Miller editorial comments: sparc specific
fields moved from iommu-common into sparc's iommu_64.h
- make the npools value an input parameter, for the case when
the iommu map size is not very large
- cookie_to_index mapping, and optimizations for span-boundary
check, for use case such as LDC.
v3: eliminate iommu_sparc, rearrange the ->demap indirection to
be invoked under the pool lock.
v4: David Miller review changes:
- s/IOMMU_ERROR_CODE/DMA_ERROR_CODE
- page_table_map_base and page_table_shift are unsigned long, not u32.
v5: removed ->cookie_to_index and ->demap indirection from the
iommu_tbl_ops The caller needs to call these functions as needed,
before invoking the generic arena allocator functions.
Added the "skip_span_boundary" argument to iommu_tbl_pool_init() for
those callers like LDC which do no care about span boundary checks.
v6: removed iommu_tbl_ops, and instead pass the ->flush_all as
an indirection to iommu_tbl_pool_init(); only invoke ->flush_all
when there is no large_pool, based on the assumption that large-pool
usage is infrequently encountered
v7: moved pool_hash initialization to lib/iommu-common.c and cleaned up
code duplication from sun4v/sun4u/ldc.
v8: Addresses BenH comments with one exception: I've left the
IOMMU_POOL_HASH as is, so that powerpc can tailor it to their
convenience. Discard trylock for simple spin_lock to acquire pool
v9: Addresses latest BenH comments: need_flush checks, add support
for dma mask and align_order.
v10: resend without RFC tag, and new mail Message-Id.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
sparc: Make LDC use common iommu poll management functions
Note that this conversion is only being done to consolidate the
code and ensure that the common code provides the sufficient
abstraction. It is not expected to result in any noticeable
performance improvement, as there is typically one ldc_iommu
per vnet_port, and each one has 8k entries, with a typical
request for 1-4 pages. Thus LDC uses npools == 1.
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: David S. Miller <davem@davemloft.net>
sparc: Make sparc64 use scalable lib/iommu-common.c functions
In iperf experiments running linux as the Tx side (TCP client) with
10 threads results in a severe performance drop when TSO is disabled,
indicating a weakness in the software that can be avoided by using
the scalable IOMMU arena DMA allocation.
Baseline numbers before this patch:
with default settings (TSO enabled) : 9-9.5 Gbps
Disable TSO using ethtool- drops badly: 2-3 Gbps.
After this patch, iperf client with 10 threads, can give a
throughput of at least 8.5 Gbps, even when TSO is disabled.
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Break up monolithic iommu table/lock into finer graularity pools and lock
Investigation of multithreaded iperf experiments on an ethernet
interface show the iommu->lock as the hottest lock identified by
lockstat, with something of the order of 21M contentions out of
27M acquisitions, and an average wait time of 26 us for the lock.
This is not efficient. A more scalable design is to follow the ppc
model, where the iommu_map_table has multiple pools, each stretching
over a segment of the map, and with a separate lock for each pool.
This model allows for better parallelization of the iommu map search.
This patch adds the iommu range alloc/free function infrastructure.
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Len Brown [Thu, 2 Apr 2015 01:02:57 +0000 (21:02 -0400)]
tools/power turbostat: correct dumped pkg-cstate-limit value
HSW expanded MSR_PKG_CST_CONFIG_CONTROL.Package-C-State-Limit,
from bits[2:0] used by previous implementations, to [3:0].
The value 1000b is unlimited, and is used by BDW and SKL too.
Andrey Semin [Fri, 5 Dec 2014 05:07:00 +0000 (00:07 -0500)]
tools/power turbostat: correct DRAM RAPL units on recent Xeon processors
While not yet documented in the Software Developer's Manual,
the data-sheet for modern Xeon states that DRAM RAPL ENERGY units
are fixed at 15.3 uJ, rather than being discovered via MSR.
Before this patch, DRAM energy on these products is over-stated by turbostat
because the RAPL units are 4x larger.
Thomas D [Mon, 5 Jan 2015 20:37:23 +0000 (21:37 +0100)]
tools/power turbostat: Use $(CURDIR) instead of $(PWD) and add support for O= option in Makefile
Since commit ee0778a30153
("tools/power: turbostat: make Makefile a bit more capable")
turbostat's Makefile is using
[...]
BUILD_OUTPUT := $(PWD)
[...]
which obviously causes trouble when building "turbostat" with
make -C /usr/src/linux/tools/power/x86/turbostat ARCH=x86 turbostat
because GNU make does not update nor guarantee that $PWD is set.
This patch changes the Makefile to use $CURDIR instead, which GNU make
guarantees to set and update (i.e. when using "make -C ...") and also
adds support for the O= option (see "make help" in your root of your
kernel source tree for more details).
Link: https://bugs.gentoo.org/show_bug.cgi?id=533918 Fixes: ee0778a30153 ("tools/power: turbostat: make Makefile a bit more capable") Signed-off-by: Thomas D. <whissi@whissi.de> Cc: Mark Asselstine <mark.asselstine@windriver.com> Signed-off-by: Len Brown <len.brown@intel.com>
Len Brown [Tue, 24 Mar 2015 20:37:35 +0000 (16:37 -0400)]
tools/power turbostat: modprobe msr, if needed
Some distros (Ubuntu) ship the msr driver as a module.
If turbosat is run as root on those systems, and discovers
that there is no /dev/cpu/cpu0/msr, it will now "modprobe msr"
for the user.
If not root, the modprobe attempt will fail, and turbostat will exit as before:
turbostat: no /dev/cpu/0/msr, Try "# modprobe msr" : No such file or directory
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