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191,556 commits

Author SHA1 Message Date
Jason Wessel
4da75b9cea kgdb: Turn off tracing while in the debugger
The kernel debugger should turn off kernel tracing any time the
debugger is active and restore it on resume.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
2010-04-02 14:58:19 -05:00
Jason Wessel
ae6bf53e02 kgdb: use atomic_inc and atomic_dec instead of atomic_set
Memory barriers should be used for the kgdb cpu synchronization.  The
atomic_set() does not imply a memory barrier.

Reported-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-04-02 14:58:18 -05:00
Jason Wessel
62fae31219 kgdb: eliminate kgdb_wait(), all cpus enter the same way
This is a kgdb architectural change to have all the cpus (master or
slave) enter the same function.

A cpu that hits an exception (wants to be the master cpu) will call
kgdb_handle_exception() from the trap handler and then invoke a
kgdb_roundup_cpu() to synchronize the other cpus and bring them into
the kgdb_handle_exception() as well.

A slave cpu will enter kgdb_handle_exception() from the
kgdb_nmicallback() and set the exception state to note that the
processor is a slave.

Previously the salve cpu would have called kgdb_wait().  This change
allows the debug core to change cpus without resuming the system in
order to inspect arch specific cpu information.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-04-02 14:58:18 -05:00
Jason Wessel
cad08acebf kgdbts,sh: Add in breakpoint pc offset for superh
The kgdb test suite mimics the behavior of gdb.  For the sh
architecture the pc must be decremented by 2 for software breakpoint.

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
2010-04-02 14:58:17 -05:00
Jason Wessel
a0279bd580 kgdb: have ebin2mem call probe_kernel_write once
Rather than call probe_kernel_write() one byte at a time, process the
whole buffer locally and pass the entire result in one go.  This way,
architectures that need to do special handling based on the length can
do so, or we only end up calling memcpy() once.

[sonic.zhang@analog.com: Reported original problem and preliminary patch]

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2010-04-02 14:58:17 -05:00
Tom Zanussi
b1dcc03cb8 perf/scripts: Tuple was set from long in both branches in python_process_event()
This is a fix to the signed/unsigned field handling in the
Python scripting engine, based on a patch from Roel Kluin.

Basically, Python wants to use a PyInt (which is internally a
long) if it can i.e. if the value will fit into that type.  If
not, it stores it into a PyLong, which isn't actually a long,
but an arbitrary-precision integer variable.

The code below is similar to to what Python does internally, and
it seems to work as expected on the x86 and x86_64 sytems I
tested it on.

Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Roel Kluin <roel.kluin@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: rostedt@goodmis.org
LKML-Reference: <1270184305.6422.10.camel@tropicana>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 21:32:16 +02:00
Arnaldo Carvalho de Melo
2aefa4f733 perf tools: sort_dimension__add shouldn't die
Propagate error instead.

LKML-Reference: <new-submission>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-02 16:28:35 -03:00
Arnaldo Carvalho de Melo
ad5b217b15 perf session: Remove one more exit() call from library code
Return NULL instead and make the caller propagate the error.

LKML-Reference: <new-submission>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-02 16:28:31 -03:00
Arnaldo Carvalho de Melo
b9fb930477 perf hist: Only allocate callchain_node if processing callchains
The struct callchain_node size is 120 bytes, that are never used when
there are no callchains or '-g none' is specified, so conditionally
allocate it, reducing sizeof(struct hist_entry) from 210 bytes to only
96, greatly speeding the non-callchain processing.

LKML-Reference: <new-submission>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-02 16:28:28 -03:00
Arnaldo Carvalho de Melo
71cf8b8ff7 perf kmem: Fixup the symbol address before using it
We get absolute addresses in the events, but relative ones from the
symbol subsystem, so calculate the absolute address by asking for the
map where the symbol was found, that has the place where the DSO was
actually loaded.

For the core kernel this poses no problems if the kernel is not
relocated by things like kexec, or if we use /proc/kallsyms, but for
modules we were getting really large, negative offsets.

LKML-Reference: <new-submission>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-02 16:28:25 -03:00
Arnaldo Carvalho de Melo
e727ca73f8 perf kmem: Resolve kernel symbols again
Due to the assumption in perf_session__new that the kernel maps would be
created using the fake PERF_RECORD_MMAP event in a perf.data file 'perf
kmem --stat caller', that doesn't have such event, ends up not being
able to resolve the kernel addresses.

Fix it by calling perf_session__create_kernel_maps() in __cmd_kmem().

LKML-Reference: <new-submission>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-02 16:28:20 -03:00
Arnaldo Carvalho de Melo
a4e3b956a8 perf hist: Replace ->print() routines by ->snprintf() equivalents
Then hist_entry__fprintf will just us the newly introduced
hist_entry__snprintf, add the newline and fprintf it to the supplied
FILE descriptor.

This allows us to remove the use_browser checking in the color_printf
routines, that now got color_snprintf variants too.

The newt TUI browser (and other GUIs that may come in the future) don't
have to worry about stdio specific stuff in the strings they get from
the se->snprintf routines and instead use whatever means to do the
equivalent.

Also the newt TUI browser don't have to use the fmemopen() hack, instead
it can use the se->snprintf routines directly. For now tho use the
hist_entry__snprintf routine to reduce the patch size.

Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-02 16:28:15 -03:00
Arnaldo Carvalho de Melo
70162138c9 perf record: Add a fallback to the reference relocation symbol
Usually "_text" is enough, but I received reports that its not always
available, so fallback to "_stext" for the symbol we use to check if we
need to apply any relocation to all the symbols in the kernel symtab,
for when, for instance, kexec is being used.

Reported-by: Darren Hart <dvhltc@us.ibm.com>
Cc: Darren Hart <dvhltc@us.ibm.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-02 16:28:06 -03:00
Arnaldo Carvalho de Melo
c29ede615f perf tools: Allow specifying O= to build files in a separate directory
Avoiding polluting the source tree with build files.

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-02 16:28:03 -03:00
Arnaldo Carvalho de Melo
8b2c551f96 perf tools: Use -o $(BITBUCKET) in one more case
As described in 1703f2c some gcc versions has issues using /dev/null, so
use the mechanism used elsewhere.

Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-02 16:27:59 -03:00
Arnaldo Carvalho de Melo
5f4d3f8816 perf report: Add progress bars
For when we are processing the events and inserting the entries in the
browser.

Experimentation here: naming "ui_something" we may be treading into
creating a TUI/GUI set of routines that can then be implemented in terms
of multiple backends.

Also the time it takes for adding things to the "browser" takes, visually
(I guess I should do some profiling here ;-) ), more time than for
processing the events...

That means we probably need to create a custom hist_entry browser, so
that we reuse the structures we have in place instead of duplicating
them in newt.

But progress was made and at least we can see something while long files
are being loaded, that must be one of UI 101 bullet points :-)

Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-02 16:27:55 -03:00
Arnaldo Carvalho de Melo
7e5e1b1404 perf symbols: map_groups__find_symbol must return the map too
Tools need to know from which map in the map_group a symbol was resolved
to, so that, for isntance, we can annotate kernel modules symbols by
getting its precise name, etc.

Also add the _by_name variants for completeness.

Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-02 16:27:43 -03:00
Arnaldo Carvalho de Melo
c6e718ff8c perf symbols: Move more map_groups methods to map.c
While writing a standalone test app that uses the symbol system to
find kernel space symbols I noticed these also need to be moved.

Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-04-02 16:27:39 -03:00
Zhu Yi
de0f60ea94 iwlwifi: avoid Tx queue memory allocation in interface down
We used to free all the Tx queues memory when interface is brought
down and reallocate them again in interface up. This requires
order-4 allocation for txq->cmd[]. In situations like s2ram, this
usually leads to allocation failure in the memory subsystem. The
patch fixed this problem by allocating the Tx queues memory only at
the first time. Later iwl_down/iwl_up only initialize but don't
free and reallocate them. The memory is freed at the device removal
time. BTW, we have already done this for the Rx queue.

This fixed bug https://bugzilla.kernel.org/show_bug.cgi?id=15551

Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Acked-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
2010-04-02 12:18:26 -07:00
Suresh Siddha
472a474c66 x86: Fix double enable_IR_x2apic() call on SMP kernel on !SMP boards
Jan Grossmann reported kernel boot panic while booting SMP
kernel on his system with a single core cpu. SMP kernels call
enable_IR_x2apic() from native_smp_prepare_cpus() and on
platforms where the kernel doesn't find SMP configuration we
ended up again calling enable_IR_x2apic() from the
APIC_init_uniprocessor() call in the smp_sanity_check(). Thus
leading to kernel panic.

Don't call enable_IR_x2apic() and default_setup_apic_routing()
from APIC_init_uniprocessor() in CONFIG_SMP case.

NOTE: this kind of non-idempotent and assymetric initialization
sequence is rather fragile and unclean, we'll clean that up
in v2.6.35. This is the minimal fix for v2.6.34.

Reported-by: Jan.Grossmann@kielnet.net
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: <jbarnes@virtuousgeek.org>
Cc: <david.woodhouse@intel.com>
Cc: <weidong.han@intel.com>
Cc: <youquan.song@intel.com>
Cc: <Jan.Grossmann@kielnet.net>
Cc: <stable@kernel.org> # [v2.6.32.x, v2.6.33.x]
LKML-Reference: <1270083887.7835.78.camel@sbs-t61.sc.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 20:48:47 +02:00
Shanyu Zhao
04f2dec1c3 iwlwifi: use consistent table for tx data collect
When collecting tx data for non-aggregation packets in rate scaling, if
the tx data matches "other table", it still uses current table to update
the stats and calculate average throughput in function rs_collect_tx_data().
This can mess up the rate scaling data structure and cause a kernel panic
in a BUG_ON statement in rs_rate_scale_perform().

To fix this bug, we pass table pointer instead of window pointer (pointed
to by table pointer) to function rs_collect_tx_data() so that the table
being used is consistent.

Signed-off-by: Shanyu Zhao <shanyu.zhao@intel.com>
Signed-off-by: Henry Zhang <hongx.c.zhang@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
2010-04-02 11:12:37 -07:00
Zhu Yi
dd48744964 iwlwifi: fix DMA allocation warnings
Below warning is triggered sometimes at module removal time when
CONFIG_DMA_API_DEBUG is enabled. This should be caused by we didn't
unmap pending commands (enqueued, but no complete notification
received) for the Tx command queue.

[ 1583.107469] ------------[ cut here ]------------
[ 1583.107539] WARNING: at lib/dma-debug.c:688
dma_debug_device_change+0x13c/0x180()
[ 1583.107617] Hardware name: ...
[ 1583.107664] pci 0000:04:00.0: DMA-API: device driver has pending DMA
allocations while released from device [count=1]
[ 1583.107713] Modules linked in: ...
[ 1583.111661] Pid: 16970, comm: modprobe Tainted: G        W
2.6.34-rc1-wl #33
[ 1583.111727] Call Trace:
[ 1583.111779]  [<c02a281c>] ? dma_debug_device_change+0x13c/0x180
[ 1583.111833]  [<c02a281c>] ? dma_debug_device_change+0x13c/0x180
[ 1583.111908]  [<c0138e11>] warn_slowpath_common+0x71/0xd0
[ 1583.111963]  [<c02a281c>] ? dma_debug_device_change+0x13c/0x180
[ 1583.112016]  [<c0138ebb>] warn_slowpath_fmt+0x2b/0x30
[ 1583.112086]  [<c02a281c>] dma_debug_device_change+0x13c/0x180
[ 1583.112142]  [<c03e6c33>] notifier_call_chain+0x53/0x90
[ 1583.112198]  [<c03e1ebe>] ? down_read+0x6e/0x90
[ 1583.112271]  [<c015b229>] __blocking_notifier_call_chain+0x49/0x70
[ 1583.112326]  [<c015b26f>] blocking_notifier_call_chain+0x1f/0x30
[ 1583.112380]  [<c031931c>] __device_release_driver+0x8c/0xa0
[ 1583.112451]  [<c03193bf>] driver_detach+0x8f/0xa0
[ 1583.112538]  [<c0318382>] bus_remove_driver+0x82/0x100
[ 1583.112595]  [<c0319ad9>] driver_unregister+0x49/0x80
[ 1583.112671]  [<c024feb2>] ? sysfs_remove_file+0x12/0x20
[ 1583.112727]  [<c02aa292>] pci_unregister_driver+0x32/0x80
[ 1583.112791]  [<fc13a3c1>] iwl_exit+0x12/0x19 [iwlagn]
[ 1583.112848]  [<c017940a>] sys_delete_module+0x15a/0x210
[ 1583.112870]  [<c015a5db>] ? up_read+0x1b/0x30
[ 1583.112893]  [<c029600c>] ? trace_hardirqs_off_thunk+0xc/0x10
[ 1583.112924]  [<c0295ffc>] ? trace_hardirqs_on_thunk+0xc/0x10
[ 1583.112947]  [<c03e6a1f>] ? do_page_fault+0x1ff/0x3c0
[ 1583.112978]  [<c03e36f6>] ? restore_all_notrace+0x0/0x18
[ 1583.113002]  [<c016aa70>] ? trace_hardirqs_on_caller+0x20/0x190
[ 1583.113025]  [<c0102d58>] sysenter_do_call+0x12/0x38
[ 1583.113054] ---[ end trace fc23e059cc4c2ced ]---

Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
2010-04-02 11:12:20 -07:00
Peter Zijlstra
371fd7e7a5 sched: Add enqueue/dequeue flags
In order to reduce the dependency on TASK_WAKING rework the enqueue
interface to support a proper flags field.

Replace the int wakeup, bool head arguments with an int flags argument
and create the following flags:

  ENQUEUE_WAKEUP - the enqueue is a wakeup of a sleeping task,
  ENQUEUE_WAKING - the enqueue has relative vruntime due to
                   having sched_class::task_waking() called,
  ENQUEUE_HEAD - the waking task should be places on the head
                 of the priority queue (where appropriate).

For symmetry also convert sched_class::dequeue() to a flags scheme.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 20:12:05 +02:00
Peter Zijlstra
cc87f76a60 sched: Fix nr_uninterruptible count
The cpuload calculation in calc_load_account_active() assumes
rq->nr_uninterruptible will not change on an offline cpu after
migrate_nr_uninterruptible(). However the recent migrate on wakeup
changes broke that and would result in decrementing the offline cpu's
rq->nr_uninterruptible.

Fix this by accounting the nr_uninterruptible on the waking cpu.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 20:12:04 +02:00
Peter Zijlstra
65cc8e4859 sched: Optimize task_rq_lock()
Now that we hold the rq->lock over set_task_cpu() again, we can do
away with most of the TASK_WAKING checks and reduce them again to
set_cpus_allowed_ptr().

Removes some conditionals from scheduling hot-paths.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Oleg Nesterov <oleg@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 20:12:04 +02:00
Peter Zijlstra
0017d73509 sched: Fix TASK_WAKING vs fork deadlock
Oleg noticed a few races with the TASK_WAKING usage on fork.

 - since TASK_WAKING is basically a spinlock, it should be IRQ safe
 - since we set TASK_WAKING (*) without holding rq->lock it could
   be there still is a rq->lock holder, thereby not actually
   providing full serialization.

(*) in fact we clear PF_STARTING, which in effect enables TASK_WAKING.

Cure the second issue by not setting TASK_WAKING in sched_fork(), but
only temporarily in wake_up_new_task() while calling select_task_rq().

Cure the first by holding rq->lock around the select_task_rq() call,
this will disable IRQs, this however requires that we push down the
rq->lock release into select_task_rq_fair()'s cgroup stuff.

Because select_task_rq_fair() still needs to drop the rq->lock we
cannot fully get rid of TASK_WAKING.

Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 20:12:03 +02:00
Oleg Nesterov
9084bb8246 sched: Make select_fallback_rq() cpuset friendly
Introduce cpuset_cpus_allowed_fallback() helper to fix the cpuset problems
with select_fallback_rq(). It can be called from any context and can't use
any cpuset locks including task_lock(). It is called when the task doesn't
have online cpus in ->cpus_allowed but ttwu/etc must be able to find a
suitable cpu.

I am not proud of this patch. Everything which needs such a fat comment
can't be good even if correct. But I'd prefer to not change the locking
rules in the code I hardly understand, and in any case I believe this
simple change make the code much more correct compared to deadlocks we
currently have.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20100315091027.GA9155@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 20:12:03 +02:00
Oleg Nesterov
6a1bdc1b57 sched: _cpu_down(): Don't play with current->cpus_allowed
_cpu_down() changes the current task's affinity and then recovers it at
the end. The problems are well known: we can't restore old_allowed if it
was bound to the now-dead-cpu, and we can race with the userspace which
can change cpu-affinity during unplug.

_cpu_down() should not play with current->cpus_allowed at all. Instead,
take_cpu_down() can migrate the caller of _cpu_down() after __cpu_disable()
removes the dying cpu from cpu_online_mask.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20100315091023.GA9148@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 20:12:03 +02:00
Oleg Nesterov
30da688ef6 sched: sched_exec(): Remove the select_fallback_rq() logic
sched_exec()->select_task_rq() reads/updates ->cpus_allowed lockless.
This can race with other CPUs updating our ->cpus_allowed, and this
looks meaningless to me.

The task is current and running, it must have online cpus in ->cpus_allowed,
the fallback mode is bogus. And, if ->sched_class returns the "wrong" cpu,
this likely means we raced with set_cpus_allowed() which was called
for reason, why should sched_exec() retry and call ->select_task_rq()
again?

Change the code to call sched_class->select_task_rq() directly and do
nothing if the returned cpu is wrong after re-checking under rq->lock.

From now task_struct->cpus_allowed is always stable under TASK_WAKING,
select_fallback_rq() is always called under rq-lock or the caller or
the caller owns TASK_WAKING (select_task_rq).

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20100315091019.GA9141@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 20:12:02 +02:00
Oleg Nesterov
c1804d547d sched: move_task_off_dead_cpu(): Remove retry logic
The previous patch preserved the retry logic, but it looks unneeded.

__migrate_task() can only fail if we raced with migration after we dropped
the lock, but in this case the caller of set_cpus_allowed/etc must initiate
migration itself if ->on_rq == T.

We already fixed p->cpus_allowed, the changes in active/online masks must
be visible to racer, it should migrate the task to online cpu correctly.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20100315091014.GA9138@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 20:12:02 +02:00
Oleg Nesterov
1445c08d06 sched: move_task_off_dead_cpu(): Take rq->lock around select_fallback_rq()
move_task_off_dead_cpu()->select_fallback_rq() reads/updates ->cpus_allowed
lockless. We can race with set_cpus_allowed() running in parallel.

Change it to take rq->lock around select_fallback_rq(). Note that it is not
trivial to move this spin_lock() into select_fallback_rq(), we must recheck
the task was not migrated after we take the lock and other callers do not
need this lock.

To avoid the races with other callers of select_fallback_rq() which rely on
TASK_WAKING, we also check p->state != TASK_WAKING and do nothing otherwise.
The owner of TASK_WAKING must update ->cpus_allowed and choose the correct
CPU anyway, and the subsequent __migrate_task() is just meaningless because
p->se.on_rq must be false.

Alternatively, we could change select_task_rq() to take rq->lock right
after it calls sched_class->select_task_rq(), but this looks a bit ugly.

Also, change it to not assume irqs are disabled and absorb __migrate_task_irq().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20100315091010.GA9131@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 20:12:01 +02:00
Oleg Nesterov
897f0b3c3f sched: Kill the broken and deadlockable cpuset_lock/cpuset_cpus_allowed_locked code
This patch just states the fact the cpusets/cpuhotplug interaction is
broken and removes the deadlockable code which only pretends to work.

- cpuset_lock() doesn't really work. It is needed for
  cpuset_cpus_allowed_locked() but we can't take this lock in
  try_to_wake_up()->select_fallback_rq() path.

- cpuset_lock() is deadlockable. Suppose that a task T bound to CPU takes
  callback_mutex. If cpu_down(CPU) happens before T drops callback_mutex
  stop_machine() preempts T, then migration_call(CPU_DEAD) tries to take
  cpuset_lock() and hangs forever because CPU is already dead and thus
  T can't be scheduled.

- cpuset_cpus_allowed_locked() is deadlockable too. It takes task_lock()
  which is not irq-safe, but try_to_wake_up() can be called from irq.

Kill them, and change select_fallback_rq() to use cpu_possible_mask, like
we currently do without CONFIG_CPUSETS.

Also, with or without this patch, with or without CONFIG_CPUSETS, the
callers of select_fallback_rq() can race with each other or with
set_cpus_allowed() pathes.

The subsequent patches try to to fix these problems.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20100315091003.GA9123@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 20:12:01 +02:00
Li Zefan
25c2d55c00 sched: Remove USER_SCHED from documentation
USER_SCHED has been removed, so update the documentation
accordingly.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Serge E. Hallyn <serue@us.ibm.com>
LKML-Reference: <4BA9A07E.8070508@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 20:12:01 +02:00
Li Zefan
32bd7eb5a7 sched: Remove remaining USER_SCHED code
This is left over from commit 7c9414385e ("sched: Remove USER_SCHED"")

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Dhaval Giani <dhaval.giani@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: David Howells <dhowells@redhat.com>
LKML-Reference: <4BA9A05F.7010407@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 20:12:00 +02:00
Oleg Nesterov
47a70985e5 sched: set_cpus_allowed_ptr(): Don't use rq->migration_thread after unlock
Trivial typo fix. rq->migration_thread can be NULL after
task_rq_unlock(), this is why we have "mt" which should be
 used instead.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20100330165829.GA18284@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 20:11:05 +02:00
Mike Galbraith
269484a492 sched: Fix proc_sched_set_task()
Latencytop clearing sum_exec_runtime via proc_sched_set_task() breaks
task_times().  Other places in kernel use nvcsw and nivcsw, which are
being cleared as well,  Clear task statistics only.

Reported-by: Török Edwin <edwintorok@gmail.com>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1269940193.19286.14.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 20:06:40 +02:00
Ingo Molnar
c9494727cf Merge branch 'linus' into sched/core
Merge reason: update to latest upstream

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 20:03:08 +02:00
Peter Zijlstra
40b91cd10f perf, x86: Add Nehalem programming quirk to Westmere
According to the Xeon-5600 errata the Westmere suffers the same PMU
programming bug as the original Nehalem did.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 19:52:06 +02:00
Peter Zijlstra
caaa8be3b6 perf, x86: Fix __initconst vs const
All variables that have __initconst should also be const.

Suggested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 19:52:05 +02:00
Peter Zijlstra
b4cdc5c264 perf, x86: Fix up the ANY flag stuff
Stephane noticed that the ANY flag was in generic arch code, and Cyrill
reported that it broke the P4 code.

Solve this by merging x86_pmu::raw_event into x86_pmu::hw_config and
provide intel_pmu and amd_pmu specific versions of this callback.

The intel_pmu one deals with the ANY flag, the amd_pmu adds the few extra
event bits AMD64 has.

Reported-by: Stephane Eranian <eranian@google.com>
Reported-by: Cyrill Gorcunov <gorcunov@gmail.com>
Acked-by: Robert Richter <robert.richter@amd.com>
Acked-by: Cyrill Gorcunov <gorcunov@gmail.com>
Acked-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1269968113.5258.442.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 19:52:04 +02:00
Robert Richter
a098f4484b perf, x86: implement ARCH_PERFMON_EVENTSEL bit masks
ARCH_PERFMON_EVENTSEL bit masks are often used in the kernel. This
patch adds macros for the bit masks and removes local defines. The
function intel_pmu_raw_event() becomes x86_pmu_raw_event() which is
generic for x86 models and same also for p6. Duplicate code is
removed.

Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20100330092821.GH11907@erda.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 19:52:03 +02:00
Robert Richter
948b1bb89a perf, x86: Undo some some *_counter* -> *_event* renames
The big rename:

 cdd6c48 perf: Do the big rename: Performance Counters -> Performance Events

accidentally renamed some members of stucts that were named after
registers in the spec. To avoid confusion this patch reverts some
changes. The related specs are MSR descriptions in AMD's BKDGs and the
ARCHITECTURAL PERFORMANCE MONITORING section in the Intel 64 and IA-32
Architectures Software Developer's Manuals.

This patch does:

 $ sed -i -e 's:num_events:num_counters:g' \
   arch/x86/include/asm/perf_event.h \
   arch/x86/kernel/cpu/perf_event_amd.c \
   arch/x86/kernel/cpu/perf_event.c \
   arch/x86/kernel/cpu/perf_event_intel.c \
   arch/x86/kernel/cpu/perf_event_p6.c \
   arch/x86/kernel/cpu/perf_event_p4.c \
   arch/x86/oprofile/op_model_ppro.c

 $ sed -i -e 's:event_bits:cntval_bits:g' -e 's:event_mask:cntval_mask:g' \
   arch/x86/kernel/cpu/perf_event_amd.c \
   arch/x86/kernel/cpu/perf_event.c \
   arch/x86/kernel/cpu/perf_event_intel.c \
   arch/x86/kernel/cpu/perf_event_p6.c \
   arch/x86/kernel/cpu/perf_event_p4.c

Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1269880612-25800-2-git-send-email-robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 19:52:02 +02:00
Ingo Molnar
ec5e61aabe Merge branch 'perf/urgent' into perf/core
Conflicts:
	arch/x86/kernel/cpu/perf_event.c

Merge reason: Resolve the conflict, pick up fixes

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 19:38:10 +02:00
Masami Hiramatsu
75ec5a245c perf probe: Fix to close dwarf when failing to analyze it
Fix to close libdw routine when failing to analyze it in
find_perf_probe_point().

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
LKML-Reference: <20100402165059.23551.95587.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 19:35:44 +02:00
Masami Hiramatsu
12e5a7ae47 perf probe: Correct error message for non-structure type
perf probe outputs incorrect error message when it is called with
non-existent field on a non-data structure local variable.

<Before>
 # perf probe vfs_read 'count.hoge'
  Fatal: Structure on a register is not supported yet.
 # perf probe vfs_read 'count->hoge'
  Fatal: Semantic error: hoge must be referred by '.'

This corrects the messsage.

<After>
 # perf probe vfs_read 'count.hoge'
  Fatal: count is not a data structure.
 # perf probe vfs_read 'count->hoge'
  Fatal: count is not a data structure.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
LKML-Reference: <20100402165052.23551.75866.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 19:35:43 +02:00
Masami Hiramatsu
c9e385826d perf probe: Fix not to return non-matched file
Fix cu_find_realpath() not to return the last file path
if that is not matched to input pattern.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
LKML-Reference: <20100402165045.23551.47780.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 19:35:42 +02:00
Masami Hiramatsu
085ea739ad perf probe: Fix --line syntax help and document
Just fix typos. --line option accepts ':START-END' syntax,
not ':START:END'.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
LKML-Reference: <20100402165038.23551.62590.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 19:35:42 +02:00
Mike Galbraith
8bb39f9aa0 perf: Fix 'perf sched record' deadlock
perf sched record can deadlock a box should the holder of
handle->data->lock take an interrupt, and then attempt to
acquire an rq lock held by a CPU trying to acquire the
same lock. Disable interrupts.

   CPU0                            CPU1
   sched event with rq->lock held
                                   grab handle->data->lock
   spin on handle->data->lock
                                   interrupt
                                   try to grab rq->lock

Reported-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Tested-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1269598293.6174.8.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 19:30:05 +02:00
Torok Edwin
257ef9d21f perf, x86: Fix callgraphs of 32-bit processes on 64-bit kernels
When profiling a 32-bit process on a 64-bit kernel, callgraph tracing
stopped after the first function, because it has seen a garbage memory
address (tried to interpret the frame pointer, and return address as a
64-bit pointer).

Fix this by using a struct stack_frame with 32-bit pointers when the
TIF_IA32 flag is set.

Note that TIF_IA32 flag must be used, and not is_compat_task(), because
the latter is only set when the 32-bit process is executing a syscall,
which may not always be the case (when tracing page fault events for
example).

Signed-off-by: Török Edwin <edwintorok@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: x86@kernel.org
Cc: linux-kernel@vger.kernel.org
LKML-Reference: <1268820436-13145-1-git-send-email-edwintorok@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 19:30:03 +02:00
Peter Zijlstra
b38b24ead3 perf, x86: Fix AMD hotplug & constraint initialization
Commit 3f6da39 ("perf: Rework and fix the arch CPU-hotplug hooks") moved
the amd northbridge allocation from CPUS_ONLINE to CPUS_PREPARE_UP
however amd_nb_id() doesn't work yet on prepare so it would simply bail
basically reverting to a state where we do not properly track node wide
constraints - causing weird perf results.

Fix up the AMD NorthBridge initialization code by allocating from
CPU_UP_PREPARE and installing it from CPU_STARTING once we have the
proper nb_id. It also properly deals with the allocation failing.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
[ robustify using amd_has_nb() ]
Signed-off-by: Stephane Eranian <eranian@google.com>
LKML-Reference: <1269353485.5109.48.camel@twins>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-02 19:30:02 +02:00