When a lock is acquired after beeing contended, we update the
wait time statistics for the given lock.
But if the min wait time is updated, we don't check the max wait
time. This is wrong because the first time we update the wait time,
we want to update both min and max wait time.
Before:
Name acquired contended total wait (ns) max wait (ns) min wait (ns)
key 8 1 21656 0 21656
After:
Name acquired contended total wait (ns) max wait (ns) min wait (ns)
key 8 1 21656 21656 21656
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
This adds the "info" subcommand to perf lock which can be used
to dump metadata like threads or addresses of lock instances.
"map" was removed because info should do the work for it.
This will be useful not only for debugging but also for ordinary
analyzing.
v2: adding example of usage
% sudo ./perf lock info -t
| Thread ID: comm
| 0: swapper
| 1: init
| 18: migration/5
| 29: events/2
| 32: events/5
| 33: events/6
...
% sudo ./perf lock info -m
| Address of instance: name of class
| 0xffff8800b95adae0: &(&sighand->siglock)->rlock
| 0xffff8800bbb41ae0: &(&sighand->siglock)->rlock
| 0xffff8800bf165ae0: &(&sighand->siglock)->rlock
| 0xffff8800b9576a98: &p->cred_guard_mutex
| 0xffff8800bb890a08: &(&p->alloc_lock)->rlock
| 0xffff8800b9522a08: &(&p->alloc_lock)->rlock
| 0xffff8800bb8aaa08: &(&p->alloc_lock)->rlock
| 0xffff8800bba72a08: &(&p->alloc_lock)->rlock
| 0xffff8800bf18ea08: &(&p->alloc_lock)->rlock
| 0xffff8800b8a0d8a0: &(&ip->i_lock)->mr_lock
| 0xffff88009bf818a0: &(&ip->i_lock)->mr_lock
| 0xffff88004c66b8a0: &(&ip->i_lock)->mr_lock
| 0xffff8800bb6478a0: &(shost->host_lock)->rlock
v3: fixed some problems Frederic pointed out
* better rbtree tracking in dump_threads()
* removed printf() and used pr_info() and pr_debug()
Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
LKML-Reference: <1272863520-16179-1-git-send-email-mitake@dcl.info.waseda.ac.jp>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
The current events reordering algorithm is based on a heuristic that
gets broken once we deal with a very fast flow of events.
Indeed the time period based flushing is not suitable anymore
in the following case, assuming we have a flush period of two
seconds.
CPU 0 | CPU 1
|
cnt1 timestamps | cnt1 timestamps
|
0 | 0
1 | 1
2 | 2
3 | 3
[...] | [...]
4 seconds later
If we spend too much time to read the buffers (case of a lot of
events to record in each buffers or when we have a lot of CPU buffers
to read), in the next pass the CPU 0 buffer could contain a slice
of several seconds of events. We'll read them all and notice we've
reached the period to flush. In the above example we flush the first
half of the CPU 0 buffer, then we read the CPU 1 buffer where we
have events that were on the flush slice and then the reordering
fails.
It's simple to reproduce with:
perf lock record perf bench sched messaging
To solve this, we use a new solution that doesn't rely on an
heuristical time slice period anymore but on a deterministic basis
based on how perf record does its job.
perf record saves the buffers through passes. A pass is a tour
on every buffers from every CPUs. This is made in order: for
each CPU we read the buffers of every counters. So the more
buffers we visit, the later will be the timstamps of their events.
When perf record finishes a pass it records a
PERF_RECORD_FINISHED_ROUND pseudo event.
We record the max timestamp t found in the pass n. Assuming these
timestamps are monotonic across cpus, we know that if a buffer
still has events with timestamps below t, they will be all available
and then read in the pass n + 1.
Hence when we start to read the pass n + 2, we can safely flush every
events with timestamps below t.
============ PASS n =================
CPU 0 | CPU 1
|
cnt1 timestamps | cnt2 timestamps
1 | 2
2 | 3
- | 4 <--- max recorded
============ PASS n + 1 ==============
CPU 0 | CPU 1
|
cnt1 timestamps | cnt2 timestamps
3 | 5
4 | 6
5 | 7 <---- max recorded
Flush every events below timestamp 4
============ PASS n + 2 ==============
CPU 0 | CPU 1
|
cnt1 timestamps | cnt2 timestamps
6 | 8
7 | 9
- | 10
Flush every events below timestamp 7
etc...
It also works on perf.data versions that don't have
PERF_RECORD_FINISHED_ROUND pseudo events. The difference is that
the events will be only flushed in the end of the perf.data
processing. It will then consume more memory and scale less with
large perf.data files.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
In order to provide a more rubust and deterministic reordering
algorithm, we need to know when we reach a point where we just
did a pass through over every counter buffers to read every thing
they had.
This patch introduces a new PERF_RECORD_FINISHED_ROUND pseudo event
that only consist in an event header and doesn't need to contain
anything.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
When !CONFIG_SMP, cpu_stop functions weren't defined at all which
could lead to build failures if UP code uses cpu_stop facility. Add
dummy cpu_stop implementation for UP. The waiting variants execute
the work function directly with preempt disabled and
stop_one_cpu_nowait() schedules a workqueue work.
Makefile and ifdefs around stop_machine implementation are updated to
accomodate CONFIG_SMP && !CONFIG_STOP_MACHINE case.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Ingo Molnar <mingo@elte.hu>
Steven reported:
|
| I'm getting:
|
| Pid: 3477, comm: perf Not tainted 2.6.34-rc6 #2727
| Call Trace:
| [<ffffffff811c7565>] debug_smp_processor_id+0xd5/0xf0
| [<ffffffff81019874>] p4_hw_config+0x2b/0x15c
| [<ffffffff8107acbc>] ? trace_hardirqs_on_caller+0x12b/0x14f
| [<ffffffff81019143>] hw_perf_event_init+0x468/0x7be
| [<ffffffff810782fd>] ? debug_mutex_init+0x31/0x3c
| [<ffffffff810c68b2>] T.850+0x273/0x42e
| [<ffffffff810c6cab>] sys_perf_event_open+0x23e/0x3f1
| [<ffffffff81009e6a>] ? sysret_check+0x2e/0x69
| [<ffffffff81009e32>] system_call_fastpath+0x16/0x1b
|
| When running perf record in latest tip/perf/core
|
Due to the fact that p4 counters are shared between HT threads
we synthetically divide the whole set of counters into two
non-intersected subsets. And while we're "borrowing" counters
from these subsets we should not be preempted (well, strictly
speaking in p4_hw_config we just pre-set reference to the
subset which allow to save some cycles in schedule routine
if it happens on the same cpu). So use get_cpu/put_cpu pair.
Also p4_pmu_schedule_events should use smp_processor_id rather
than raw_ version. This allow us to catch up preemption issue
(if there will ever be).
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Tested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Lin Ming <ming.m.lin@intel.com>
LKML-Reference: <20100508112716.963478928@openvz.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Commit 6bde9b6ce0 ("perf: Add
group scheduling transactional APIs") added code to allow a
group to be scheduled in a single transaction. However, it
introduced a bug in handling events whose pmu does not implement
transactions -- at the end of scheduling in the events in the
group, in the non-transactional case the code now falls through
to the group_error label, and proceeds to unschedule all the
events in the group and return failure.
This fixes it by returning 0 (success) in the non-transactional
case.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Lin Ming <ming.m.lin@intel.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: eranian@gmail.com
LKML-Reference: <20100508105800.GB10650@brick.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The patch adds the ENDPROC declarations for the __copy_to_user_std and
__clear_user_std functions. Without these, the compiler generates BXL to
ARM when compiling the kernel in Thumb-2 mode.
Reported-by: Kyungmin Park <kmpark@infradead.org>
Tested-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The standard I-cache Invalidate All (ICIALLU) and Branch Predication
Invalidate All (BPIALL) operations are not automatically broadcast to
the other CPUs in an ARMv7 MP system. The patch adds the Inner Shareable
variants, ICIALLUIS and BPIALLIS, if ARMv7 and SMP.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The Snoop Control Unit on the ARM11MPCore hardware does not detect the
cache operations and the dma_cache_maint*() functions may leave stale
cache entries on other CPUs. The solution implemented in this patch
performs a Read or Write For Ownership in the ARMv6 DMA cache
maintenance functions. These LDR/STR instructions change the cache line
state to shared or exclusive so that the cache maintenance operation has
the desired effect.
Tested-by: George G. Davis <gdavis@mvista.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit 7959722 introduced calls to copy_(to|from)_user_page() from
access_process_vm() in mm/nommu.c. The copy_to_user_page() was not
implemented on noMMU ARM.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit 31aa8fd6 introduced the __arm_ioremap_caller() function but the
nommu.c version did not have the _caller suffix.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit 23caaf19b ("ALSA: usb-mixer: Add support for Audio Class v2.0")
broke support for Class1 devices due to two faulty changes. This patch
fixes it.
Signed-off-by: Daniel Mack <daniel@caiaq.de>
Reported-and-Tested-by: The Source <thesourcehim@gmail.com>
Cc: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
A while back there was a discussion regarding the rt_secret_interval timer.
Given that we've had the ability to do emergency route cache rebuilds for awhile
now, based on a statistical analysis of the various hash chain lengths in the
cache, the use of the flush timer is somewhat redundant. This patch removes the
rt_secret_interval sysctl, allowing us to rely solely on the statistical
analysis mechanism to determine the need for route cache flushes.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Previously we just set them to dpms off. This should save
additional power.
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Clean up the hypervisor layer and the hypervisor drivers, using an ops
structure instead of an enumeration with if statements.
The identity of the hypervisor, if needed, can be tested by testing
the pointer value in x86_hyper.
The MS-HyperV private state is moved into a normal global variable
(it's per-system state, not per-CPU state). Being a normal bss
variable, it will be left at all zero on non-HyperV platforms, and so
can generally be tested for HyperV-specific features without
additional qualification.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Acked-by: Greg KH <greg@kroah.com>
Cc: Hank Janssen <hjanssen@microsoft.com>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Ky Srinivasan <ksrinivasan@novell.com>
LKML-Reference: <4BE49778.6060800@zytor.com>
This should have been GPLv2 only, we cut and pasted from the wrong file
originally, sorry.
Also removed some unneeded boilerplate license code, we all know where
to find the GPLv2, and that there's no warranty as that is implicit from
the license.
Cc: Ky Srinivasan <ksrinivasan@novell.com>
Cc: Hank Janssen <hjanssen@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
LKML-Reference: <20100507235541.GA15448@kroah.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Properly localize error cleanup, and make sure that the iomem regions are
unmapped if framebuffer initialization fails.
Reported-by: Bruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
gpiochip_remove() is not meant to be called with interrupts disabled, and
there is no need for the lock here in any case.
Reported-by: Bruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
viafb: make procfs entries optional
This patch adds a config option to enable procfs entries for direct
hardware access. This was the old behaviour but the option defaults
to no as this is really ugly and should not be needed if the driver
works correct (and if it doesn't, it needs to be fixed).
That stuff is really something that should
- not be needed at all (the driver should be capable of doing it)
- not be there (debugfs would be better for such things)
So add this option just for backwards compatiblity.
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
viafb: fix proc entry removal
Trying to remove unregistered proc entries became painful and is
useless anyway. So remove the removal of an entry that was never
registered and duplicate the logic for one which is added
conditionally. Additionally move the removal above releasing fb_info
as we still need the information.
This prevents tainting the kernel by the procfs warn on and
avoiding access to already freed memory is probably also a good idea.
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
viafb: improve misc register handling
This patch improves the misc register handling by adding a modify
function for this to via_io.h and moving expanded definitions of the
relevant ports there. The code was changed to use those to improve
readability.
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
viafb: replace inb/outb
This patch replaces occurences of inb/outb with via_write_reg and
via_write_reg_mask where this is possible to improve code
readability.
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
viafb: move some modesetting functions to a seperate file
This patch moves the modesetting functions which are already cleaned up
to a seperate file.
Just the beginning to bring some structure in this mess.
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
viafb: unify modesetting functions
This patch unifies some cleaned up modesetting functions to prepare for
moving them to an extra file. This includes make them use via_io and
changing there names to reflect that they do not depend on anything
framebuffer specific.
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
The camera engine captures to framebuffer memory, so we need to set some
aside for that purpose. There is no proper memory allocator for fbmem;
instead, accel.c just trims some space off the top. Alas, without creating
that proper memory allocator, the only way to make this work is to hack it
into the same bit of code in accel.c. The allocation must happen *after*
the others (some code, including user-space XV stuff, makes assumptions on
where the cursor space is), and before the rest of the framebuffer is set
up.
Cc: ScottFang@viatech.com.cn
Cc: JosephChan@via.com.tw
Cc: Harald Welte <laforge@gnumonks.org>
Acked-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
