linux-toradex.git/kernel/stop_machine.c, branch v2.6.22-rc7

stop_machine() now uses hard_irq_disable

2007-05-11T15:29:34+00:00

Add a call to hard_irq_disable() to stop_machine so that we make sure IRQs are
really disabled and not only lazy-disabled on archs like powerpc as some users
of stop_machine() may rely on that.

[akpm@linux-foundation.org: build fix]
Signed-off-by: Benjamin Herrenschmidt 
Acked-by: Rusty Russell 
Cc: Paul Mackerras 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Use stop_machine_run in the Intel RNG driver

2007-05-08T18:15:00+00:00

Replace call_smp_function with stop_machine_run in the Intel RNG driver.

CPU A has done read_lock(&lock)
CPU B has done write_lock_irq(&lock) and is waiting for A to release the lock.

A third CPU calls call_smp_function and issues the IPI.  CPU A takes CPU
C's IPI.  CPU B is waiting with interrupts disabled and does not see the
IPI.  CPU C is stuck waiting for CPU B to respond to the IPI.

Deadlock.

The solution is to use stop_machine_run instead of call_smp_function
(call_smp_function should not be called in situations where the CPUs may be
suspended).

[haruo.tomita@toshiba.co.jp: fix a typo in mod_init()]
[haruo.tomita@toshiba.co.jp: fix memory leak]
Signed-off-by: Prarit Bhargava 
Cc: Jan Beulich 
Cc: "Tomita, Haruo" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] stop_machine.c copyright

2006-09-29T16:18:24+00:00

I had to look back: this code was extracted from the module.c code in 2005.

Signed-off-by: Rusty Russell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] Remove redundant up() in stop_machine()

2006-08-27T18:01:31+00:00

An up() is called in kernel/stop_machine.c on failure, and also in the
caller (unconditionally).

Signed-off-by: Zhou Yingchao 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] revert "kthread: convert stop_machine into a kthread"

2006-07-04T04:25:20+00:00

Jiri reports that the stop_machin kthread conversion caused his machine to
hang when suspending.  Hyperthreading is apparently involved.

I don't see why that would be and I can't reproduce it.  Revert to the 2.6.17
code.

Cc: "Serge E. Hallyn" 
Cc: Jiri Slaby 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] kthread: convert stop_machine into a kthread

2006-06-25T17:01:22+00:00

- Update stop_machine.c to spawn stop_machine as kthreads rather than the
  deprecated kernel_threads.

- Update stop_machine to use the more efficient kthread_bind() before
  running task in place of set_cpus_allowed() after.

[akpm@osdl.org: remove now-wrong set_cpus_allowed()]
Signed-off-by: Serge E. Hallyn 
Cc: Rusty Russell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] Remove set_fs() in stop_machine()

2006-01-10T16:01:25+00:00


)

From: Brian Gerst 

Call sched_setscheduler() directly instead.

Signed-off-by: Brian Gerst 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] stop_machine() vs. synchronous IPI send deadlock

2005-11-14T02:14:16+00:00

This fixes deadlock of stop_machine() vs.  synchronous IPI send.  The
problem is that stop_machine() disables interrupts before disabling
preemption on other CPUs.  So if another CPU is preempted and then calls
something like flush_tlb_all() it will deadlock with CPU doing
stop_machine() and which can't process IPI due to disabled IRQs.

I changed stop_machine() to do the same things exactly as it does on other
CPUs, i.e.  it should disable preemption first on _all_ CPUs including
itself and only after that disable IRQs.

Signed-off-by: Kirill Korotaev 
Cc: Rusty Russell 
Cc: "Andrey Savochkin" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] smp_processor_id() cleanup

2005-06-22T01:46:13+00:00

This patch implements a number of smp_processor_id() cleanup ideas that
Arjan van de Ven and I came up with.

The previous __smp_processor_id/_smp_processor_id/smp_processor_id API
spaghetti was hard to follow both on the implementational and on the
usage side.

Some of the complexity arose from picking wrong names, some of the
complexity comes from the fact that not all architectures defined
__smp_processor_id.

In the new code, there are two externally visible symbols:

 - smp_processor_id(): debug variant.

 - raw_smp_processor_id(): nondebug variant. Replaces all existing
   uses of _smp_processor_id() and __smp_processor_id(). Defined
   by every SMP architecture in include/asm-*/smp.h.

There is one new internal symbol, dependent on DEBUG_PREEMPT:

 - debug_smp_processor_id(): internal debug variant, mapped to
                             smp_processor_id().

Also, i moved debug_smp_processor_id() from lib/kernel_lock.c into a new
lib/smp_processor_id.c file.  All related comments got updated and/or
clarified.

I have build/boot tested the following 8 .config combinations on x86:

 {SMP,UP} x {PREEMPT,!PREEMPT} x {DEBUG_PREEMPT,!DEBUG_PREEMPT}

I have also build/boot tested x64 on UP/PREEMPT/DEBUG_PREEMPT.  (Other
architectures are untested, but should work just fine.)

Signed-off-by: Ingo Molnar 
Signed-off-by: Arjan van de Ven 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] use smp_mb/wmb/rmb where possible

2005-05-01T15:58:47+00:00

Replace a number of memory barriers with smp_ variants.  This means we won't
take the unnecessary hit on UP machines.

Signed-off-by: Anton Blanchard 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds