02 Nov, 2009
1 commit
-
Currently, rcu_irq_exit() is invoked only for CONFIG_NO_HZ,
while rcu_irq_enter() is invoked unconditionally. This patch
moves rcu_irq_exit() out from under CONFIG_NO_HZ so that the
calls are balanced.This patch has no effect on the behavior of the kernel because
both rcu_irq_enter() and rcu_irq_exit() are empty for
!CONFIG_NO_HZ, but the code is easier to understand if the calls
are obviously balanced in all cases.Signed-off-by: Lai Jiangshan
Signed-off-by: Paul E. McKenney
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference:
Signed-off-by: Ingo Molnar
27 Oct, 2009
1 commit
-
Use lockdep_set_class() to simplify the code and to avoid any
additional overhead in the !LOCKDEP case. Also move the
definition of rcu_root_class into kernel/rcutree.c, as suggested
by Lai Jiangshan.Signed-off-by: Peter Zijlstra
Signed-off-by: Paul E. McKenney
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference:
Signed-off-by: Ingo Molnar
26 Oct, 2009
5 commits
-
No change in functionality - just straighten out a few small
stylistic details.Cc: Paul E. McKenney
Cc: David Howells
Cc: Josh Triplett
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: avi@redhat.com
Cc: mtosatti@redhat.com
LKML-Reference:
Signed-off-by: Ingo Molnar -
Make rcutorture list the available torture_type values when it
doesn't like the one specified.Signed-off-by: Paul E. McKenney
Acked-by: Josh Triplett
Reviewed-by: Lai Jiangshan
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
Cc: avi@redhat.com
Cc: mtosatti@redhat.com
LKML-Reference:
Signed-off-by: Ingo Molnar -
Adds the "srcu_expedited" torture type, and also renames
sched_ops_sync to sched_sync_ops for consistency while we are in
this file.Signed-off-by: Paul E. McKenney
Acked-by: Josh Triplett
Reviewed-by: Lai Jiangshan
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
Cc: avi@redhat.com
Cc: mtosatti@redhat.com
LKML-Reference:
Signed-off-by: Ingo Molnar -
This patch creates a synchronize_srcu_expedited() that uses
synchronize_sched_expedited() where synchronize_srcu()
uses synchronize_sched(). The synchronize_srcu() and
synchronize_srcu_expedited() functions become one-liners that
pass synchronize_sched() or synchronize_sched_expedited(),
repectively, to a new __synchronize_srcu() function.While in the file, move the EXPORT_SYMBOL_GPL()s to immediately
follow the corresponding functions.Requested-by: Avi Kivity
Tested-by: Marcelo Tosatti
Signed-off-by: Paul E. McKenney
Acked-by: Josh Triplett
Reviewed-by: Lai Jiangshan
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
Cc: avi@redhat.com
LKML-Reference:
Signed-off-by: Ingo Molnar -
This patch is a version of RCU designed for !SMP provided for a
small-footprint RCU implementation. In particular, the
implementation of synchronize_rcu() is extremely lightweight and
high performance. It passes rcutorture testing in each of the
four relevant configurations (combinations of NO_HZ and PREEMPT)
on x86. This saves about 1K bytes compared to old Classic RCU
(which is no longer in mainline), and more than three kilobytes
compared to Hierarchical RCU (updated to 2.6.30):CONFIG_TREE_RCU:
text data bss dec filename
183 4 0 187 kernel/rcupdate.o
2783 520 36 3339 kernel/rcutree.o
3526 Total (vs 4565 for v7)CONFIG_TREE_PREEMPT_RCU:
text data bss dec filename
263 4 0 267 kernel/rcupdate.o
4594 776 52 5422 kernel/rcutree.o
5689 Total (6155 for v7)CONFIG_TINY_RCU:
text data bss dec filename
96 4 0 100 kernel/rcupdate.o
734 24 0 758 kernel/rcutiny.o
858 Total (vs 848 for v7)The above is for x86. Your mileage may vary on other platforms.
Further compression is possible, but is being procrastinated.Changes from v7 (http://lkml.org/lkml/2009/10/9/388)
o Apply Lai Jiangshan's review comments (aside from
might_sleep() in synchronize_sched(), which is covered by SMP builds).o Fix up expedited primitives.
Changes from v6 (http://lkml.org/lkml/2009/9/23/293).
o Forward ported to put it into the 2.6.33 stream.
o Added lockdep support.
o Make lightweight rcu_barrier.
Changes from v5 (http://lkml.org/lkml/2009/6/23/12).
o Ported to latest pre-2.6.32 merge window kernel.
- Renamed rcu_qsctr_inc() to rcu_sched_qs().
- Renamed rcu_bh_qsctr_inc() to rcu_bh_qs().
- Provided trivial rcu_cpu_notify().
- Provided trivial exit_rcu().
- Provided trivial rcu_needs_cpu().
- Fixed up the rcu_*_enter/exit() functions in linux/hardirq.h.o Removed the dependence on EMBEDDED, with a view to making
TINY_RCU default for !SMP at some time in the future.o Added (trivial) support for expedited grace periods.
Changes from v4 (http://lkml.org/lkml/2009/5/2/91) include:
o Squeeze the size down a bit further by removing the
->completed field from struct rcu_ctrlblk.o This permits synchronize_rcu() to become the empty function.
Previous concerns about rcutorture were unfounded, as
rcutorture correctly handles a constant value from
rcu_batches_completed() and rcu_batches_completed_bh().Changes from v3 (http://lkml.org/lkml/2009/3/29/221) include:
o Changed rcu_batches_completed(), rcu_batches_completed_bh()
rcu_enter_nohz(), rcu_exit_nohz(), rcu_nmi_enter(), and
rcu_nmi_exit(), to be static inlines, as suggested by David
Howells. Doing this saves about 100 bytes from rcutiny.o.
(The numbers between v3 and this v4 of the patch are not directly
comparable, since they are against different versions of Linux.)Changes from v2 (http://lkml.org/lkml/2009/2/3/333) include:
o Fix whitespace issues.
o Change short-circuit "||" operator to instead be "+" in order
to fix performance bug noted by "kraai" on LWN.(http://lwn.net/Articles/324348/)
Changes from v1 (http://lkml.org/lkml/2009/1/13/440) include:
o This version depends on EMBEDDED as well as !SMP, as suggested
by Ingo.o Updated rcu_needs_cpu() to unconditionally return zero,
permitting the CPU to enter dynticks-idle mode at any time.
This works because callbacks can be invoked upon entry to
dynticks-idle mode.o Paul is now OK with this being included, based on a poll at
the Kernel Miniconf at linux.conf.au, where about ten people said
that they cared about saving 900 bytes on single-CPU systems.o Applies to both mainline and tip/core/rcu.
Signed-off-by: Paul E. McKenney
Acked-by: David Howells
Acked-by: Josh Triplett
Reviewed-by: Lai Jiangshan
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: avi@redhat.com
Cc: mtosatti@redhat.com
LKML-Reference:
Signed-off-by: Ingo Molnar
15 Oct, 2009
4 commits
-
Signed-off-by: Paul E. McKenney
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
Cc: npiggin@suse.de
Cc: jens.axboe@oracle.com
Cc: Josh Triplett
LKML-Reference:
Signed-off-by: Ingo Molnar
kernel/rcutree_trace.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-) -
For the short term, map synchronize_rcu_expedited() to
synchronize_rcu() for TREE_PREEMPT_RCU and to
synchronize_sched_expedited() for TREE_RCU.Longer term, there needs to be a real expedited grace period for
TREE_PREEMPT_RCU, but candidate patches to date are considerably
more complex and intrusive.Signed-off-by: Paul E. McKenney
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
Cc: npiggin@suse.de
Cc: jens.axboe@oracle.com
LKML-Reference:
Signed-off-by: Ingo Molnar -
As the number of callbacks on a given CPU rises, invoke
force_quiescent_state() only every blimit number of callbacks
(defaults to 10,000), and even then only if no other CPU has
invoked force_quiescent_state() in the meantime.This should fix the performance regression reported by Nick.
Reported-by: Nick Piggin
Signed-off-by: Paul E. McKenney
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
Cc: jens.axboe@oracle.com
LKML-Reference:
Signed-off-by: Ingo Molnar -
If userspace tries to perform a requeue_pi on a non-requeue_pi waiter,
it will find the futex_q->requeue_pi_key to be NULL and OOPS.Check for NULL in match_futex() instead of doing explicit NULL pointer
checks on all call sites. While match_futex(NULL, NULL) returning
false is a little odd, it's still correct as we expect valid key
references.Signed-off-by: Darren Hart
Cc: Peter Zijlstra
Cc: Ingo Molnar
CC: Eric Dumazet
CC: Dinakar Guniguntala
CC: John Stultz
Cc: stable@kernel.org
LKML-Reference:
Signed-off-by: Thomas Gleixner
14 Oct, 2009
1 commit
-
The futex code does not handle spurious wake up in futex_wait and
futex_wait_requeue_pi.The code assumes that any wake up which was not caused by futex_wake /
requeue or by a timeout was caused by a signal wake up and returns one
of the syscall restart error codes.In case of a spurious wake up the signal delivery code which deals
with the restart error codes is not invoked and we return that error
code to user space. That causes applications which actually check the
return codes to fail. Blaise reported that on preempt-rt a python test
program run into a exception trap. -rt exposed that due to a built in
spurious wake up accelerator :)Solve this by checking signal_pending(current) in the wake up path and
handle the spurious wake up case w/o returning to user space.Reported-by: Blaise Gassend
Debugged-by: Darren Hart
Signed-off-by: Thomas Gleixner
Cc: Peter Zijlstra
Cc: stable@kernel.org
LKML-Reference:
09 Oct, 2009
6 commits
-
Some tracepoint magic (TRACE_EVENT(lock_acquired)) relies on
the fact that lock hold times are positive and uses div64 on
that. That triggered a build warning on MIPS, and probably
causes bad output in certain circumstances as well.Make it truly positive.
Reported-by: Andrew Morton
Signed-off-by: Peter Zijlstra
LKML-Reference:
Signed-off-by: Ingo Molnar -
…/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
futex: fix requeue_pi key imbalance
futex: Fix typo in FUTEX_WAIT/WAKE_BITSET_PRIVATE definitions
rcu: Place root rcu_node structure in separate lockdep class
rcu: Make hot-unplugged CPU relinquish its own RCU callbacks
rcu: Move rcu_barrier() to rcutree
futex: Move exit_pi_state() call to release_mm()
futex: Nullify robust lists after cleanup
futex: Fix locking imbalance
panic: Fix panic message visibility by calling bust_spinlocks(0) before dying
rcu: Replace the rcu_barrier enum with pointer to call_rcu*() function
rcu: Clean up code based on review feedback from Josh Triplett, part 4
rcu: Clean up code based on review feedback from Josh Triplett, part 3
rcu: Fix rcu_lock_map build failure on CONFIG_PROVE_LOCKING=y
rcu: Clean up code to address Ingo's checkpatch feedback
rcu: Clean up code based on review feedback from Josh Triplett, part 2
rcu: Clean up code based on review feedback from Josh Triplett -
…l/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
sched: Set correct normal_prio and prio values in sched_fork() -
…nel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
tracing: user local buffer variable for trace branch tracer
tracing: fix warning on kernel/trace/trace_branch.c andtrace_hw_branches.c
ftrace: check for failure for all conversions
tracing: correct module boundaries for ftrace_release
tracing: fix transposed numbers of lock_depth and preempt_count
trace: Fix missing assignment in trace_ctxwake_*
tracing: Use free_percpu instead of kfree
tracing: Check total refcount before releasing bufs in profile_enable failure -
…/linux/kernel/git/tip/linux-2.6-tip
* 'sparc-perf-events-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
mm, perf_event: Make vmalloc_user() align base kernel virtual address to SHMLBA
perf_event: Provide vmalloc() based mmap() backing -
…el/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
perf_events: Make ABI definitions available to userspace
perf tools: elf_sym__is_function() should accept "zero" sized functions
tracing/syscalls: Use long for syscall ret format and field definitions
perf trace: Update eval_flag() flags array to match interrupt.h
perf trace: Remove unused code in builtin-trace.c
perf: Propagate term signal to child
08 Oct, 2009
6 commits
-
Just using the tr->buffer for the API to trace_buffer_lock_reserve
is not good enough. This is because the tr->buffer may change, and we
do not want to commit with a different buffer that we reserved from.This patch uses a local variable to hold the buffer that was used to
reserve and commit with.Signed-off-by: Steven Rostedt
-
fix warnings that caused the API change of trace_buffer_lock_reserve()
change files: kernel/trace/trace_hw_branch.c
kernel/trace/trace_branch.cSigned-off-by: Zhenwen Xu
LKML-Reference:
Signed-off-by: Steven Rostedt -
Due to legacy code from back when the dynamic tracer used a daemon,
only core kernel code was checking for failures. This is no longer
the case. We must check for failures any time we perform text modifications.Cc: stable@kernel.org
Signed-off-by: Steven Rostedt -
When the module is about the unload we release its call records.
The ftrace_release function was given wrong values representing
the module core boundaries, thus not releasing its call records.Plus making ftrace_release function module specific.
Signed-off-by: Jiri Olsa
LKML-Reference:
Cc: stable@kernel.org
Signed-off-by: Steven Rostedt -
If futex_wait_requeue_pi() wakes prior to requeue, we drop the
reference to the source futex_key twice, once in
handle_early_requeue_pi_wakeup() and once on our way out.Remove the drop from the handle_early_requeue_pi_wakeup() and keep
the get/drops together in futex_wait_requeue_pi().Reported-by: Helge Bahmann
Signed-off-by: Darren Hart
Cc: Helge Bahmann
Cc: Peter Zijlstra
Cc: Eric Dumazet
Cc: Dinakar Guniguntala
Cc: John Stultz
Cc: stable-2.6.31
LKML-Reference:
Signed-off-by: Thomas Gleixner -
The lock_depth and preempt_count numbers in the latency format is
transposed.Signed-off-by: Steven Rostedt
07 Oct, 2009
4 commits
-
Commit f2e21c9610991e95621a81407cdbab881226419b had unfortunate side
effects with cpufreq governors on some systems.If the system did not switch into NOHZ mode ts->inidle is not set when
tick_nohz_stop_sched_tick() is called from the idle routine. Therefor
all subsequent calls from irq_exit() to tick_nohz_stop_sched_tick()
fail to call tick_nohz_start_idle(). This results in bogus idle
accounting information which is passed to cpufreq governors.Set the inidle flag unconditionally of the NOHZ active state to keep
the idle time accounting correct in any case.[ tglx: Added comment and tweaked the changelog ]
Reported-by: Steven Noonan
Signed-off-by: Eero Nurkkala
Cc: Rik van Riel
Cc: Venkatesh Pallipadi
Cc: Greg KH
Cc: Steven Noonan
Cc: stable@kernel.org
LKML-Reference:
Signed-off-by: Thomas Gleixner -
Before this patch, all of the rcu_node structures were in the same lockdep
class, so that lockdep would complain when rcu_preempt_offline_tasks()
acquired the root rcu_node structure's lock while holding one of the leaf
rcu_nodes' locks.This patch changes rcu_init_one() to use a separate
spin_lock_init() for the root rcu_node structure's lock than is
used for that of all of the rest of the rcu_node structures, which
puts the root rcu_node structure's lock in its own lockdep class.Suggested-by: Peter Zijlstra
Signed-off-by: Paul E. McKenney
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference:
Signed-off-by: Ingo Molnar -
The current interaction between RCU and CPU hotplug requires that
RCU block in CPU notifiers waiting for callbacks to drain.This can be greatly simplified by having each CPU relinquish its
own callbacks, and for both _rcu_barrier() and CPU_DEAD notifiers
to adopt all callbacks that were previously relinquished.This change also eliminates the possibility of certain types of
hangs due to the previous practice of waiting for callbacks to be
invoked from within CPU notifiers. If you don't every wait, you
cannot hang.Signed-off-by: Paul E. McKenney
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference:
Signed-off-by: Ingo Molnar -
Move the existing rcu_barrier() implementation to rcutree.c,
consistent with the fact that the rcu_barrier() implementation is
tied quite tightly to the RCU implementation.This opens the way to simplify and fix rcutree.c's rcu_barrier()
implementation in a later patch.Signed-off-by: Paul E. McKenney
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference:
Signed-off-by: Ingo Molnar
06 Oct, 2009
12 commits
-
exit_pi_state() is called from do_exit() but not from do_execve().
Move it to release_mm() so it gets called from do_execve() as well.Signed-off-by: Thomas Gleixner
LKML-Reference:
Cc: stable@kernel.org
Cc: Anirban Sinha
Cc: Peter Zijlstra -
The robust list pointers of user space held futexes are kept intact
over an exec() call. When the exec'ed task exits exit_robust_list() is
called with the stale pointer. The risk of corruption is minimal, but
still it is incorrect to keep the pointers valid. Actually glibc
should uninstall the robust list before calling exec() but we have to
deal with it anyway.Nullify the pointers after [compat_]exit_robust_list() has been
called.Reported-by: Anirban Sinha
Signed-off-by: Peter Zijlstra
Signed-off-by: Thomas Gleixner
LKML-Reference:
Cc: stable@kernel.org -
The state char variable S should be reassigned, if S == 0.
We are missing the state of the task that is going to sleep for the
context switch events (in the raw mode).Fortunately the problem arises with the sched_switch/wake_up
tracers, not the sched trace events.The formers are legacy now. But still, that was buggy.
Signed-off-by: Hiroshi Shimamoto
Cc: Steven Rostedt
Acked-by: Frederic Weisbecker
LKML-Reference:
Signed-off-by: Ingo Molnar -
Some architectures such as Sparc, ARM and MIPS (basically
everything with flush_dcache_page()) need to deal with dcache
aliases by carefully placing pages in both kernel and user maps.These architectures typically have to use vmalloc_user() for this.
However, on other architectures, vmalloc() is not needed and has
the downsides of being more restricted and slower than regular
allocations.Signed-off-by: Peter Zijlstra
Acked-by: David Miller
Cc: Andrew Morton
Cc: Jens Axboe
Cc: Paul Mackerras
LKML-Reference:
Signed-off-by: Ingo Molnar -
The syscall event definitions use long for the syscall exit ret
value, but unsigned long for the same thing in the format and field
definitions. Change them all to long.Signed-off-by: Tom Zanussi
Acked-by: Frederic Weisbecker
Cc: rostedt@goodmis.org
Cc: lizf@cn.fujitsu.com
Cc: Peter Zijlstra
Cc: Mike Galbraith
Cc: Paul Mackerras
Cc: Arnaldo Carvalho de Melo
LKML-Reference:
Signed-off-by: Ingo Molnar -
Rich reported a lock imbalance in the futex code:
http://bugzilla.kernel.org/show_bug.cgi?id=14288
It's caused by the displacement of the retry_private label in
futex_wake_op(). The code unlocks the hash bucket locks in the
error handling path and retries without locking them again which
makes the next unlock fail.Move retry_private so we lock the hash bucket locks when we retry.
Reported-by: Rich Ercolany
Signed-off-by: Thomas Gleixner
Cc: Peter Zijlstra
Cc: Darren Hart
Cc: stable-2.6.31
LKML-Reference:
Signed-off-by: Ingo Molnar -
Commit ffd71da4e3f ("panic: decrease oops_in_progress only after
having done the panic") moved bust_spinlocks(0) to the end of the
function, which in practice is never reached.As a result console_unblank() is not called, and on some systems
the user may not see the panic message.Move it back up to before the unblanking.
Signed-off-by: Aaro Koskinen
Reviewed-by: Frederic Weisbecker
LKML-Reference:
Signed-off-by: Ingo Molnar -
…/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
perf tools: Run generate-cmdlist.sh properly
perf_event: Clean up perf_event_init_task()
perf_event: Fix event group handling in __perf_event_sched_*()
perf timechart: Add a power-only mode
perf top: Add poll_idle to the skip list -
…el/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
hrtimer: Remove overly verbose "switch to high res mode" message -
…nel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
kmemtrace: Fix up tracer registration
tracing: Fix infinite recursion in ftrace_update_pid_func() -
The rcu_barrier enum causes several problems:
(1) you have to define the enum somewhere, and there is no
convenient place,(2) the difference between TREE_RCU and TREE_PREEMPT_RCU causes
problems when you need to map from rcu_barrier enum to struct
rcu_state,(3) the switch statement are large, and
(4) TINY_RCU really needs a different rcu_barrier() than do the
treercu implementations.So replace it with a functionally equivalent but cleaner function
pointer abstraction.Signed-off-by: Paul E. McKenney
Acked-by: Mathieu Desnoyers
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference:
Signed-off-by: Ingo Molnar -
These issues identified during an old-fashioned face-to-face code
review extending over many hours. This group improves an existing
abstraction and introduces two new ones. It also fixes an RCU
stall-warning bug found while making the other changes.o Make RCU_INIT_FLAVOR() declare its own variables, removing
the need to declare them at each call site.o Create an rcu_for_each_leaf() macro that scans the leaf
nodes of the rcu_node tree.o Create an rcu_for_each_node_breadth_first() macro that does
a breadth-first traversal of the rcu_node tree, AKA
stepping through the array in index-number order.o If all CPUs corresponding to a given leaf rcu_node
structure go offline, then any tasks queued on that leaf
will be moved to the root rcu_node structure. Therefore,
the stall-warning code must dump out tasks queued on the
root rcu_node structure as well as those queued on the leaf
rcu_node structures.Signed-off-by: Paul E. McKenney
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference:
Signed-off-by: Ingo Molnar
