Commit graph

119953 commits

Author SHA1 Message Date
Ingo Molnar 92bf73e90a Merge branch 'x86/irq' into perfcounters/core
( with manual semantic merge of arch/x86/kernel/cpu/perf_counter.c )
2008-12-12 12:00:14 +01:00
Hiroshi Shimamoto 915b0d0104 x86: hardirq: introduce inc_irq_stat()
Impact: cleanup

Introduce inc_irq_stat() macro and unify irq_stat accounting code.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-12 11:59:49 +01:00
Ingo Molnar fd10902797 Merge commit 'v2.6.28-rc8' into x86/irq 2008-12-12 11:59:39 +01:00
Ingo Molnar 447557ac7c perf counters: update docs
Impact: update docs

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-11 20:41:00 +01:00
Ingo Molnar 6a930700c8 perf counters: clean up state transitions
Impact: cleanup

Introduce a proper enum for the 3 states of a counter:

	PERF_COUNTER_STATE_OFF		= -1
	PERF_COUNTER_STATE_INACTIVE	=  0
	PERF_COUNTER_STATE_ACTIVE	=  1

and rename counter->active to counter->state and propagate the
changes everywhere.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-11 15:45:56 +01:00
Ingo Molnar 1d1c7ddbfa perf counters: add prctl interface to disable/enable counters
Add a way for self-monitoring tasks to disable/enable counters summarily,
via a prctl:

	PR_TASK_PERF_COUNTERS_DISABLE		31
	PR_TASK_PERF_COUNTERS_ENABLE		32

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-11 15:45:55 +01:00
Ingo Molnar bae43c9945 perf counters: implement PERF_COUNT_TASK_CLOCK
Impact: add new perf-counter type

The 'task clock' counter counts the amount of time a task is executing,
in nanoseconds. It stops ticking when a task is scheduled out either due
to it blocking, sleeping or it being preempted.

This counter type is a Linux kernel based abstraction, it is available
even if the hardware does not support native hardware performance counters.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-11 15:45:54 +01:00
Ingo Molnar 01b2838c42 perf counters: consolidate hw_perf save/restore APIs
Impact: cleanup

Rename them to better match up the usual IRQ disable/enable APIs:

 hw_perf_disable_all()  => hw_perf_save_disable()
 hw_perf_restore_ctrl() => hw_perf_restore()

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-11 15:45:53 +01:00
Ingo Molnar 5c92d12411 perf counters: implement PERF_COUNT_CPU_CLOCK
Impact: add new perf-counter type

The 'CPU clock' counter counts the amount of CPU clock time that is
elapsing, in nanoseconds. (regardless of how much of it the task is
spending on a CPU executing)

This counter type is a Linux kernel based abstraction, it is available
even if the hardware does not support native hardware performance counters.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-11 15:45:52 +01:00
Ingo Molnar 621a01eac8 perf counters: hw driver API
Impact: restructure code, introduce hw_ops driver abstraction

Introduce this abstraction to handle counter details:

 struct hw_perf_counter_ops {
	void (*hw_perf_counter_enable)	(struct perf_counter *counter);
	void (*hw_perf_counter_disable)	(struct perf_counter *counter);
	void (*hw_perf_counter_read)	(struct perf_counter *counter);
 };

This will be useful to support assymetric hw details, and it will also
be useful to implement "software counters". (Counters that count kernel
managed sw events such as pagefaults, context-switches, wall-clock time
or task-local time.)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-11 15:45:51 +01:00
Ingo Molnar ccff286d85 perf counters: group counter, fixes
Impact: bugfix

Check that a group does not span outside the context of a CPU or a task.

Also, do not allow deep recursive hierarchies.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-11 15:45:50 +01:00
Ingo Molnar 04289bb989 perf counters: add support for group counters
Impact: add group counters

This patch adds the "counter groups" abstraction.

Groups of counters behave much like normal 'single' counters, with a
few semantic and behavioral extensions on top of that.

A counter group is created by creating a new counter with the open()
syscall's group-leader group_fd file descriptor parameter pointing
to another, already existing counter.

Groups of counters are scheduled in and out in one atomic group, and
they are also roundrobin-scheduled atomically.

Counters that are member of a group can also record events with an
(atomic) extended timestamp that extends to all members of the group,
if the record type is set to PERF_RECORD_GROUP.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-11 15:45:49 +01:00
Ingo Molnar 9f66a3810f perf counters: restructure the API
Impact: clean up new API

Thorough cleanup of the new perf counters API, we now get clean separation
of the various concepts:

 - introduce perf_counter_hw_event to separate out the event source details

 - move special type flags into separate attributes: PERF_COUNT_NMI,
   PERF_COUNT_RAW

 - extend the type to u64 and reserve it fully to the architecture in the
   raw type case.

And make use of all these changes in the core and x86 perfcounters code.

Also change the syscall signature to:

  asmlinkage int sys_perf_counter_open(

	struct perf_counter_hw_event	*hw_event_uptr		__user,
	pid_t				pid,
	int				cpu,
	int				group_fd);

( Note that group_fd is unused for now - it's reserved for the counter
  groups abstraction. )

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-11 15:45:48 +01:00
Thomas Gleixner dfa7c899b4 perf counters: expand use of counter->event
Impact: change syscall, cleanup

Make use of the new perf_counters event type.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-11 15:45:47 +01:00
Thomas Gleixner eab656ae04 perf counters: clean up 'raw' type API
Impact: cleanup

Introduce a separate hw_event type.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-11 15:45:46 +01:00
Thomas Gleixner 4ac13294e4 perf counters: protect them against CSTATE transitions
Impact: fix rare lost events problem

There are CPUs whose performance counters misbehave on CSTATE transitions,
so provide a way to just disable/enable them around deep idle methods.

(hw_perf_enable_all() is cheap on x86.)

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-11 15:45:45 +01:00
Linus Torvalds 8b1fae4e42 Linux 2.6.28-rc8 2008-12-10 15:11:51 -08:00
Linus Torvalds f9fc05e762 Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/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: CPU remove deadlock fix
2008-12-10 14:41:06 -08:00
Hugh Dickins b88ed20594 fix mapping_writably_mapped()
Lee Schermerhorn noticed yesterday that I broke the mapping_writably_mapped
test in 2.6.7!  Bad bad bug, good good find.

The i_mmap_writable count must be incremented for VM_SHARED (just as
i_writecount is for VM_DENYWRITE, but while holding the i_mmap_lock)
when dup_mmap() copies the vma for fork: it has its own more optimal
version of __vma_link_file(), and I missed this out.  So the count
was later going down to 0 (dangerous) when one end unmapped, then
wrapping negative (inefficient) when the other end unmapped.

The only impact on x86 would have been that setting a mandatory lock on
a file which has at some time been opened O_RDWR and mapped MAP_SHARED
(but not necessarily PROT_WRITE) across a fork, might fail with -EAGAIN
when it should succeed, or succeed when it should fail.

But those architectures which rely on flush_dcache_page() to flush
userspace modifications back into the page before the kernel reads it,
may in some cases have skipped the flush after such a fork - though any
repetitive test will soon wrap the count negative, in which case it will
flush_dcache_page() unnecessarily.

Fix would be a two-liner, but mapping variable added, and comment moved.

Reported-by: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 14:40:45 -08:00
Linus Torvalds f4fd2c5b6f Merge branch 'to-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/frob/linux-2.6-roland
* 'to-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/frob/linux-2.6-roland:
  tracehook: exec double-reporting fix
2008-12-10 14:40:21 -08:00
Manfred Spraul 711a49a07f lib/idr.c: Fix bug introduced by RCU fix
The last patch to lib/idr.c caused a bug if idr_get_new_above() was
called on an empty idr.

Usually, nodes stay on the same layer.  New layers are added to the top
of the tree.

The exception is idr_get_new_above() on an empty tree: In this case, the
new root node is first added on layer 0, then moved upwards.  p->layer
was not updated.

As usual: You shall never rely on the source code comments, they will
only mislead you.

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 13:34:33 -08:00
Akira Takeuchi c7f8d6f6b5 MN10300: Give correct size when reserving interrupt vector table
Give the correct size when reserving the interrupt vector table.  It should be
a page not a single byte.

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 13:34:33 -08:00
Akira Takeuchi 54b71fba68 MN10300: Fix __put_user_asm8()
Fix __put_user_asm8() by jumping to the end label (3:) from the exception
handler, rather than jumping back to retry the second store instruction (label
2:).

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 13:34:33 -08:00
Akira Takeuchi 24646bd226 MN10300: Fix the preemption resume_kernel() routine
Fix the preemption resume_kernel() routine by inverting the test to see
whether interrupts are off (IM7 is all enabled, not all disabled).

Furthermore, interrupts should be disabled on entry to resume_kernel() so that
they're correctly set for jumping to restore_all() and doing the need
reschedule test.

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 13:34:33 -08:00
Akira Takeuchi a8893fb3e6 MN10300: Discard low-priority Tx interrupts when closing an on-chip serial port
Discard low-prioriy Tx interrupts when closing an MN10300 on-chip serial port.

The MN10300 on-chip serial port uses three interrupts to manage its serial
ports:

 (1) A very high priority interrupt that drives virtual DMA for Rx.

 (2) A very high priority interrupt that drives virtual DMA for Tx.

 (3) A normal priority virtual interrupt that does the normal UART interrupt
     stuff and is shared between Rx and Tx.

mn10300_serial_stop_tx() only disables the high priority Tx interrupt.  It
doesn't also disable the normal priority one because it is shared with Rx.

However, the high priority interrupt may interrupt local_irq_disabled()
sections, and so may have queued up a low priority virtual interrupt whilst the
UART driver is asking for the Tx interrupt to be disabled.

The result of this can be an oops when we try to process the interrupt in
mn10300_serial_transmit_interrupt() as port->uart.info and port->uart.info->tty
may have gone away.

To deal with this, if either of those pointers is NULL, we make sure the
high-priority Tx interrupt is disabled and discard the interrupt.  The low
priority interrupt is disabled by the mn10300_serial_pic irq_chip table.

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 13:34:33 -08:00
Cyrill Gorcunov cb32898c09 MN10300: vmlinux.lds.S cleanup - use PAGE_SIZE, PERCPU macros
Include the linux/page.h header into the MN10300 kernel linker script thus
allowing us to use PAGE_SIZE macro instead of a numeric constant.

Also use the PERCPU macro instead of an explicit section definition.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 13:34:33 -08:00
Linus Torvalds 4e6f2ba97f Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: api - Disallow cryptomgr as a module if algorithms are built-in
2008-12-10 10:13:57 -08:00
Linus Torvalds 44f6cc318a Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
  PCIe: ASPM: Break out of endless loop waiting for PCI config bits to switch
  PCI: stop leaking 'slot_name' in pci_create_slot
2008-12-10 10:04:50 -08:00
Linus Torvalds 061afe9fe1 Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6:
  [IA64] SN: prevent IRQ retargetting in request_irq()
  [IA64] Fix section mismatch ioc3uart_init()/ioc3uart_submodule
  [IA64] Clear up section mismatch for ioc4_ide_attach_one.
  [IA64] Clear up section mismatch with arch_unregister_cpu()
  [IA64] Clear up section mismatch for sn_check_wars.
  [IA64] Updated the generic_defconfig to work with the 2.6.28-rc7 kernel.
  [IA64] Fix GRU compile error w/o CONFIG_HUGETLB_PAGE
  [IA64] eliminate NULL test and memset after alloc_bootmem
  [IA64] remove BUILD_BUG_ON from paravirt_getreg()
2008-12-10 10:04:25 -08:00
Linus Torvalds 942c88cc11 Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
  MIPS: Better than nothing implementation of PCI mmap to fix X.
2008-12-10 10:03:55 -08:00
Kay Sievers cba767175b pktcdvd: remove broken dev_t export of class devices
The pktcdvd created class devices only export some sysfs files,
but have no char dev_t registered in the driver.

At class device creation time they copy the dev_t value of the
block device to the char device, wich will register a new char
device in the driver core and userspace, with a conflicting dev_t
value.

In many cases the class devices dev_t just points to a random
USB device. This fixes the sysfs "duplicate entry" errors.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Acked-by: Peter Osterlund <petero2@telia.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 10:03:32 -08:00
Linus Torvalds cdcb30b5cc Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
  firewire: fw-ohci: fix IOMMU resource exhaustion
  ieee1394: node manager causes up to ~3.25s delay in freezing tasks
2008-12-10 10:02:17 -08:00
Andrew Morton c1ab6cc68c drivers/video/mb862xx/mb862xxfb.c: fix printk
sparc64:

drivers/video/mb862xx/mb862xxfb.c:929: warning: long long unsigned int format, resource_size_t arg (arg 4)
drivers/video/mb862xx/mb862xxfb.c:931: warning: long long unsigned int format, resource_size_t arg (arg 4)

We don't know what type the architecture uses to implement u64, hence they
cannot be printed.

Cc: Anatolij Gustschin <agust@denx.de>
Cc: Dmitry Baryshkov <dbaryshkov@gmail.com>
Cc: Anton Vorontsov <avorontsov@ru.mvista.com>
Cc: Matteo Fortini <m.fortini@selcomgroup.com>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:54 -08:00
Hugh Dickins 9c24624727 KSYM_SYMBOL_LEN fixes
Miles Lane tailing /sys files hit a BUG which Pekka Enberg has tracked
to my 966c8c12dc sprint_symbol(): use
less stack exposing a bug in slub's list_locations() -
kallsyms_lookup() writes a 0 to namebuf[KSYM_NAME_LEN-1], but that was
beyond the end of page provided.

The 100 slop which list_locations() allows at end of page looks roughly
enough for all the other stuff it might print after the symbol before
it checks again: break out KSYM_SYMBOL_LEN earlier than before.

Latencytop and ftrace and are using KSYM_NAME_LEN buffers where they
need KSYM_SYMBOL_LEN buffers, and vmallocinfo a 2*KSYM_NAME_LEN buffer
where it wants a KSYM_SYMBOL_LEN buffer: fix those before anyone copies
them.

[akpm@linux-foundation.org: ftrace.h needs module.h]
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc Miles Lane <miles.lane@gmail.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Steven Rostedt <srostedt@redhat.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:54 -08:00
Dmitri Monakhov 6ee5a399d6 inotify: fix IN_ONESHOT unmount event watcher
On umount two event will be dispatched to watcher:

1: inotify_dev_queue_event(.., IN_UNMOUNT,..)
2: remove_watch(watch, dev)
    ->inotify_dev_queue_event(.., IN_IGNORED, ..)

But if watcher has IN_ONESHOT bit set then the watcher will be released
inside first event.  Which result in accessing invalid object later.  IMHO
it is not pure regression.  This bug wasn't triggered while initial
inotify interface testing phase because of another bug in IN_ONESHOT
handling logic :)

  commit ac74c00e49
  Author: Ulisses Furquim <ulissesf@gmail.com>
  Date:   Fri Feb 8 04:18:16 2008 -0800
    inotify: fix check for one-shot watches before destroying them
    As the IN_ONESHOT bit is never set when an event is sent we must check it
    in the watch's mask and not in the event's mask.

TESTCASE:
mkdir mnt
mount -ttmpfs none mnt
mkdir mnt/d
./inotify mnt/d&
umount mnt ## << lockup or crash here

TESTSOURCE:
/* gcc -oinotify inotify.c */
#include <stdio.h>
#include <stdlib.h>
#include <sys/inotify.h>

int main(int argc, char **argv)
{
        char buf[1024];
        struct inotify_event *ie;
        char *p;
        int i;
        ssize_t l;

        p = argv[1];
        i = inotify_init();
        inotify_add_watch(i, p, ~0);

        l = read(i, buf, sizeof(buf));
        printf("read %d bytes\n", l);
        ie = (struct inotify_event *) buf;
        printf("event mask: %d\n", ie->mask);
	return 0;
}

Signed-off-by: Dmitri Monakhov <dmonakhov@openvz.org>
Cc: John McCutchan <ttb@tentacle.dhs.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Robert Love <rlove@google.com>
Cc: Ulisses Furquim <ulissesf@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:53 -08:00
Eric Dumazet aa6f147966 atomic: fix a typo in atomic_long_xchg()
atomic_long_xchg() is not correctly defined for 32bit arches.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:53 -08:00
Brice Goglin 80bba1290a mm: no get_user/put_user while holding mmap_sem in do_pages_stat?
Since commit 2f007e74bb, do_pages_stat()
gets the page address from user-space and puts the corresponding status
back while holding the mmap_sem for read.  There is no need to hold
mmap_sem there while some page-faults may occur.

This patch adds a temporary address and status buffer so as to only
hold mmap_sem while working on these kernel buffers.  This is
implemented by extracting do_pages_stat_array() out of do_pages_stat().

Signed-off-by: Brice Goglin <Brice.Goglin@inria.fr>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:53 -08:00
Balaji Rao 52b9582dd5 drivers/serial/s3c2440.c: fix typo in MODULE_LICENSE
Signed-off-by: Balaji Rao <balajirrao@gmail.com>
Acked-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:53 -08:00
Matt Mackall 49c50342c7 pagemap: fix 32-bit pagemap regression
The large pages fix from bcf8039ed4 broke 32-bit pagemap by pulling the
pagemap entry code out into a function with the wrong return type.
Pagemap entries are 64 bits on all systems and unsigned long is only 32
bits on 32-bit systems.

Signed-off-by: Matt Mackall <mpm@selenic.com>
Reported-by: Doug Graham <dgraham@nortel.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: <stable@kernel.org>		[2.6.26.x, 2.6.27.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:53 -08:00
KAMEZAWA Hiroyuki 653d22c0f5 page_cgroup should ignore empty nodes
Fix a total bootup freeze on ia64.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Tested-by: Li Zefan <lizf@cn.fujitsu.com>
Reported-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:53 -08:00
Randy Dunlap cc61686001 rtc twl4030: rename ioctl function when RTC_INTF_DEV=n
Fix build error when RTC_INTF_DEV=n:

drivers/rtc/rtc-twl4030.c:402: error: 'twl4030_rtc_ioctl' undeclared here (not in a function)
make[3]: *** [drivers/rtc/rtc-twl4030.o] Error 1

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Samuel Ortiz <sameo@openedhand.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:53 -08:00
Geoff Levand beaa4867ee fbcon: fix workqueue shutdown
Add a call to cancel_work_sync() in fbcon_exit() to cancel any pending
work in the fbcon workqueue.

The current implementation of fbcon_exit() sets the fbcon workqueue
function info->queue.func to NULL, but does not assure that there is no
work pending when it does so.  On occasion, depending on system timing,
there will still be pending work in the queue when fbcon_exit() is
called.  This results in a null pointer deference when run_workqueue()
tries to call the queue's work function.

Fixes errors on shutdown similar to these:

  Console: switching to colour dummy device 80x25
  Unable to handle kernel paging request for data at address 0x00000000

Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:53 -08:00
KOSAKI Motohiro 6841c8e263 mm: remove UP version of lru_add_drain_all()
Currently, lru_add_drain_all() has two version.
  (1) use schedule_on_each_cpu()
  (2) don't use schedule_on_each_cpu()

Gerald Schaefer reported it doesn't work well on SMP (not NUMA) S390
machine.

  offline_pages() calls lru_add_drain_all() followed by drain_all_pages().
  While drain_all_pages() works on each cpu, lru_add_drain_all() only runs
  on the current cpu for architectures w/o CONFIG_NUMA. This let us run
  into the BUG_ON(!PageBuddy(page)) in __offline_isolated_pages() during
  memory hotplug stress test on s390. The page in question was still on the
  pcp list, because of a race with lru_add_drain_all() and drain_all_pages()
  on different cpus.

Actually, Almost machine has CONFIG_UNEVICTABLE_LRU=y. Then almost machine use
(1) version lru_add_drain_all although the machine is UP.

Then this ifdef is not valueable.
simple removing is better.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:53 -08:00
Andrew Morton 02d2116887 revert "percpu_counter: new function percpu_counter_sum_and_set"
Revert

    commit e8ced39d5e
    Author: Mingming Cao <cmm@us.ibm.com>
    Date:   Fri Jul 11 19:27:31 2008 -0400

        percpu_counter: new function percpu_counter_sum_and_set

As described in

	revert "percpu counter: clean up percpu_counter_sum_and_set()"

the new percpu_counter_sum_and_set() is racy against updates to the
cpu-local accumulators on other CPUs.  Revert that change.

This means that ext4 will be slow again.  But correct.

Reported-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: <linux-ext4@vger.kernel.org>
Cc: <stable@kernel.org>		[2.6.27.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:52 -08:00
Andrew Morton 71c5576fbd revert "percpu counter: clean up percpu_counter_sum_and_set()"
Revert

    commit 1f7c14c62c
    Author: Mingming Cao <cmm@us.ibm.com>
    Date:   Thu Oct 9 12:50:59 2008 -0400

        percpu counter: clean up percpu_counter_sum_and_set()

Before this patch we had the following:

percpu_counter_sum(): return the percpu_counter's value

percpu_counter_sum_and_set(): return the percpu_counter's value, copying
that value into the central value and zeroing the per-cpu counters before
returning.

After this patch, percpu_counter_sum_and_set() has gone, and
percpu_counter_sum() gets the old percpu_counter_sum_and_set()
functionality.

Problem is, as Eric points out, the old percpu_counter_sum_and_set()
functionality was racy and wrong.  It zeroes out counters on "other" cpus,
without holding any locks which will prevent races agaist updates from
those other CPUS.

This patch reverts 1f7c14c62c.  This means
that percpu_counter_sum_and_set() still has the race, but
percpu_counter_sum() does not.

Note that this is not a simple revert - ext4 has since started using
percpu_counter_sum() for its dirty_blocks counter as well.

Note that this revert patch changes percpu_counter_sum() semantics.

Before the patch, a call to percpu_counter_sum() will bring the counter's
central counter mostly up-to-date, so a following percpu_counter_read()
will return a close value.

After this patch, a call to percpu_counter_sum() will leave the counter's
central accumulator unaltered, so a subsequent call to
percpu_counter_read() can now return a significantly inaccurate result.

If there is any code in the tree which was introduced after
e8ced39d5e was merged, and which depends
upon the new percpu_counter_sum() semantics, that code will break.

Reported-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:52 -08:00
Eric Dumazet fd3d664fef percpu_counter: fix CPU unplug race in percpu_counter_destroy()
We should first delete the counter from percpu_counters list
before freeing memory, or a percpu_counter_hotcpu_callback()
could dereference a NULL pointer.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:52 -08:00
Alessandro Zummo fe102c71a6 rtc: fix missing id_table in rtc-ds1672 and rtc-max6900 drivers
Add missing id_table to the drivers in subject.  Patch is against the
latest git.  It should go in with 2.6.28 if possible, the drivers won't
work without the id_table bits.

Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Reported-by: Imre Kaloz <kaloz@openwrt.org>
Tested-by: Imre Kaloz <kaloz@openwrt.org>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:52 -08:00
Tom Zanussi fbb5b7ae4b relayfs: fix infinite loop with splice()
Running kmemtraced, which uses splice() on relayfs, causes a hard lock on
x86-64 SMP.  As described by Tom Zanussi:

  It looks like you hit the same problem as described here:

  commit 8191ecd1d1

      splice: fix infinite loop in generic_file_splice_read()

  relay uses the same loop but it never got noticed or fixed.

Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Tested-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:52 -08:00
Balbir Singh 361371201b uml: boot broken due to buffer overrun
mconsole_init() passed 256 bytes as length in os_create_unix_socket, while
the sizeof UNIX_PATH_MAX is 108. This patch fixes that problem and avoids
a big overrun bug reported on UML bootup.

sockaddr_un.sun_path is UNIX_PATH_MAX long which causes the problem.
Reported-by: Vikas K Managutte <vikki.km@gmail.com>
Reported-by: Sarvesh Kumar Lal Das <skldas@gmail.com>
Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi>
Reviewed-by: WANG Cong <wangcong@zeuux.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: <stable@kernel.org>		[please check with Jeff]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:52 -08:00
Andrew Morton 69fc208be5 mm/backing-dev.c: remove recently-added WARN_ON()
On second thoughts, this is just going to disturb people while telling us
things which we already knew.

Cc: Peter Korsgaard <jacmet@sunsite.dk>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 08:01:52 -08:00