Commit graph

18,024 commits

Author SHA1 Message Date
Ingo Molnar
9b51f66dcb perfcounters: implement "counter inheritance"
Impact: implement new performance feature

Counter inheritance can be used to run performance counters in a workload,
transparently - and pipe back the counter results to the parent counter.

Inheritance for performance counters works the following way: when creating
a counter it can be marked with the .inherit=1 flag. Such counters are then
'inherited' by all child tasks (be they fork()-ed or clone()-ed). These
counters get inherited through exec() boundaries as well (except through
setuid boundaries).

The counter values get added back to the parent counter(s) when the child
task(s) exit - much like stime/utime statistics are gathered. So inherited
counters are ideal to gather summary statistics about an application's
behavior via shell commands, without having to modify that application.

The timec.c command utilizes counter inheritance:

  http://redhat.com/~mingo/perfcounters/timec.c

Sample output:

   $ ./timec -e 1 -e 3 -e 5 ls -lR /usr/include/ >/dev/null

   Performance counter stats for 'ls':

           163516953 instructions
                2295 cache-misses
             2855182 branch-misses

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-14 20:30:49 +01:00
Ingo Molnar
ee06094f82 perfcounters: restructure x86 counter math
Impact: restructure code

Change counter math from absolute values to clear delta logic.

We try to extract elapsed deltas from the raw hw counter - and put
that into the generic counter.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-14 20:30:48 +01:00
Rusty Russell
968ea6d80e Merge ../linux-2.6-x86
Conflicts:

	arch/x86/kernel/io_apic.c
	kernel/sched.c
	kernel/sched_stats.h
2008-12-13 21:55:51 +10:30
Rusty Russell
7be7585393 cpumask: Use all NR_CPUS bits unless CONFIG_CPUMASK_OFFSTACK
Impact: futureproof as we convert more code to new APIs

The old cpumask operators treat all NR_CPUS bits as relevent, the new
ones use nr_cpumask_bits.  For large NR_CPUS and small nr_cpu_ids, this
makes a difference.

However, mixing the two can cause problems with undefined bits.  An
arch which sets CONFIG_CPUMASK_OFFSTACK should have converted across
to the new operators, so it's safe in that case.

(Thanks to Stephen Rothwell for bisecting the initial unused-bits bug,
and Mike Travis for this solution).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Mike Travis <travis@sgi.com>
2008-12-13 21:20:28 +10:30
Rusty Russell
320ab2b0b1 cpumask: convert struct clock_event_device to cpumask pointers.
Impact: change calling convention of existing clock_event APIs

struct clock_event_timer's cpumask field gets changed to take pointer,
as does the ->broadcast function.

Another single-patch change.  For safety, we BUG_ON() in
clockevents_register_device() if it's not set.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Ingo Molnar <mingo@elte.hu>
2008-12-13 21:20:26 +10:30
Rusty Russell
0de26520c7 cpumask: make irq_set_affinity() take a const struct cpumask
Impact: change existing irq_chip API

Not much point with gentle transition here: the struct irq_chip's
setaffinity method signature needs to change.

Fortunately, not widely used code, but hits a few architectures.

Note: In irq_select_affinity() I save a temporary in by mangling
irq_desc[irq].affinity directly.  Ingo, does this break anything?

(Folded in fix from KOSAKI Motohiro)

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Grant Grundler <grundler@parisc-linux.org>
Acked-by: Ingo Molnar <mingo@redhat.com>
Cc: ralf@linux-mips.org
Cc: grundler@parisc-linux.org
Cc: jeremy@xensource.com
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
2008-12-13 21:20:26 +10:30
Rusty Russell
29c0177e6a cpumask: change cpumask_scnprintf, cpumask_parse_user, cpulist_parse, and cpulist_scnprintf to take pointers.
Impact: change calling convention of existing cpumask APIs

Most cpumask functions started with cpus_: these have been replaced by
cpumask_ ones which take struct cpumask pointers as expected.

These four functions don't have good replacement names; fortunately
they're rarely used, so we just change them over.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: paulus@samba.org
Cc: mingo@redhat.com
Cc: tony.luck@intel.com
Cc: ralf@linux-mips.org
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: cl@linux-foundation.org
Cc: srostedt@redhat.com
2008-12-13 21:20:25 +10:30
Johannes Berg
4dec9b807b rfkill: strip pointless notifier chain
No users, so no reason to have it.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-12-12 14:45:25 -05:00
Senthil Balasubramanian
bb608e9db7 wireless: Incorrect LEAP authentication algorithm identifier.
This patch fixes a regression introduced by
"wireless: avoid some net/ieee80211.h vs. linux/ieee80211.h conflicts"
LEAP authentication algorithm identifier should be 128.

Signed-off-by: Senthil Balasubramanian <senthilkumar@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-12-12 13:48:20 -05:00
Mike Frysinger
c29541b24f linux/timex.h: cleanup for userspace
Impact: fix user-space exported use

Move all the kernel-specific defines and includes into the __KERNEL__
section so that they don't get leaked into userspace.

[akpm@linux-foundation.org: coding-style fixes]

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-12-12 17:01:38 +01:00
Oleg Nesterov
27af4245b6 posix-timers: use "struct pid*" instead of "struct task_struct*"
Impact: restructure, clean up code

k_itimer holds the ref to the ->it_process until sys_timer_delete(). This
allows to pin up to RLIMIT_SIGPENDING dead task_struct's. Change the code
to use "struct pid *" instead.

The patch doesn't kill ->it_process, it places ->it_pid into the union.
->it_process is still used by do_cpu_nanosleep() as before. It would be
trivial to change the nanosleep code as well, but since it uses it_process
in a special way I think it is better to keep this field for grep.

The patch bloats the kernel by 104 bytes and it also adds the new pointer,
->it_signal, to k_itimer. It is used by lock_timer() to verify that the
found timer was not created by another process. It is not clear why do we
use the global database (and thus the global idr_lock) for posix timers.
We still need the signal_struct->posix_timers which contains all useable
timers, perhaps it is better to use some form of per-process array
instead.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-12-12 17:00:07 +01:00
Stefano Panella
5b37717a23 uwb: improved MAS allocator and reservation conflict handling
Greatly enhance the MAS allocator:
  - Handle row and column reservations.
  - Permit all the available MAS to be allocated.
  - Follows the WiMedia rules on MAS selection.

Take appropriate action when reservation conflicts are detected.
  - Correctly identify which reservation wins the conflict.
  - Protect alien BP reservations.
  - If an owned reservation loses, resize/move it.
  - Follow the backoff procedure before requesting additional MAS.

When reservations are terminated, move the remaining reservations (if
necessary) so they keep following the MAS allocation rules.

Signed-off-by: Stefano Panella <stefano.panella@csr.com>
Signed-off-by: David Vrabel <david.vrabel@csr.com>
2008-12-12 13:00:06 +00:00
Ingo Molnar
8299608f14 Merge branches 'irq/sparseirq', 'x86/quirks' and 'x86/reboot' into cpus4096
We merge the irq/sparseirq, x86/quirks and x86/reboot trees into the
cpus4096 tree because the io-apic changes in the sparseirq change
conflict with the cpumask changes in the cpumask tree, and we
want to resolve those.
2008-12-12 13:49:24 +01:00
Ingo Molnar
45ab6b0c76 Merge branch 'sched/core' into cpus4096
Conflicts:
	include/linux/ftrace.h
	kernel/sched.c
2008-12-12 13:48:57 +01:00
Heiko Carstens
ee79d1bdb6 sched: let arch_update_cpu_topology indicate if topology changed
Change arch_update_cpu_topology so it returns 1 if the cpu topology changed
and 0 if it didn't change. This will be useful for the next patch which adds
a call to this function in partition_sched_domains.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-12 13:47:21 +01:00
Ingo Molnar
81444a7995 Merge branch 'tracing/fastboot' into cpus4096 2008-12-12 12:43:05 +01:00
Ingo Molnar
30cb367ea2 sparse irqs: add irqnr.h to the user headers list
Impact: fix build error

/home/mingo/tip/usr/include/linux/random.h:11: included file
'linux/irqnr.h' is not exported

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-12 12:29:10 +01:00
Ingo Molnar
0ebb26e7a4 sparse irqs: handle !GENIRQ platforms
Impact: build fix

fix:

 In file included from /home/mingo/tip/arch/m68k/amiga/amiints.c:39:
 /home/mingo/tip/include/linux/interrupt.h:21: error: expected identifier or '('
 /home/mingo/tip/arch/m68k/amiga/amiints.c: In function 'amiga_init_IRQ':

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-12 12:28:50 +01:00
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
Ingo Molnar
fd10902797 Merge commit 'v2.6.28-rc8' into x86/irq 2008-12-12 11:59:39 +01:00
Frederic Weisbecker
bcbc4f20b5 tracing/function-graph-tracer: annotate do_IRQ and smp_apic_timer_interrupt
Impact: move most important x86 irq entry-points to a separate subsection

Annotate do_IRQ and smp_apic_timer_interrupt to put them into the .irqentry.text
subsection. These function will so be recognized as hardirq entrypoints for the
function-graph-tracer. We could also annotate other irq entries but the others
are far less important but they can be added on request.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-12 11:14:08 +01:00
Ingo Molnar
c1dfdc7597 Merge commit 'v2.6.28-rc8' into sched/core 2008-12-12 10:29:35 +01:00
Markus Metzger
c2724775ce x86, bts: provide in-kernel branch-trace interface
Impact: cleanup

Move the BTS bits from ptrace.c into ds.c.

Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-12 08:08:12 +01:00
Ingo Molnar
f3134de606 Merge branches 'tracing/function-graph-tracer' and 'tracing/ring-buffer' into tracing/core 2008-12-12 07:40:08 +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
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
Christoph Hellwig
4d4be482a4 [XFS] add a FMODE flag to make XFS invisible I/O less hacky
XFS has a mode called invisble I/O that doesn't update any of the
timestamps.  It's used for HSM-style applications and exposed through
the nasty open by handle ioctl.

Instead of doing directly assignment of file operations that set an
internal flag for it add a new FMODE_NOCMTIME flag that we can check
in the normal file operations.

(addition of the generic VFS flag has been ACKed by Al as an interims
 solution)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-12-11 13:14:41 +11:00
Benjamin Thery
8229efdaef netns: ip6mr: enable namespace support in ipv6 multicast forwarding code
This last patch makes the appropriate changes to use and propagate the
network namespace where needed in IPv6 multicast forwarding code.

This consists mainly in replacing all the remaining init_net occurences
with current netns pointer retrieved from sockets, net devices or 
mfc6_caches depending on the routines' contexts.

Some routines receive a new 'struct net' parameter to propagate the current
netns:
* ip6mr_get_route
* ip6mr_cache_report
* ip6mr_cache_find
* ip6mr_cache_unresolved
* mif6_add/mif6_delete
* ip6mr_mfc_add/ip6mr_mfc_delete
* ip6mr_reg_vif

All the IPv6 multicast forwarding variables moved to struct netns_ipv6 by
the previous patches are now referenced in the correct namespace.

Changelog:
==========
* Take into account the net associated to mfc6_cache when matching entries in
  mfc_unres_queue list.
* Call mroute_clean_tables() in ip6mr_net_exit() to free memory allocated
  per-namespace.
* Call dev_net_set() in ip6mr_reg_vif() to initialize dev->nd_net 
  correctly.

Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-10 16:30:15 -08:00
Benjamin Thery
58701ad411 netns: ip6mr: store netns in struct mfc6_cache
This patch stores into struct mfc6_cache the network namespace each
mfc6_cache belongs to. The new member is mfc6_net.

mfc6_net is assigned at cache allocation and doesn't change during
the rest of the cache entry life.

This will help to retrieve the current netns around the IPv6 multicast
forwarding code.

At the moment, all mfc6_cache are allocated in init_net.

Changelog:
==========
* Use write_pnet()/read_pnet() to set and get mfc6_net.

Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-10 16:22:34 -08:00
Benjamin Thery
bd91b8bf37 netns: ip6mr: allocate mroute6_socket per-namespace.
Preliminary work to make IPv6 multicast forwarding netns-aware.

Make IPv6 multicast forwarding mroute6_socket per-namespace,
moves it into struct netns_ipv6.

At the moment, mroute6_socket is only referenced in init_net.

Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-10 16:07:08 -08:00
Steve Glendinning
2107fb8b5b smsc911x: add dynamic bus configuration
Convert the driver to select 16-bit or 32-bit bus access at runtime,
at a small performance cost.

Signed-off-by: Steve Glendinning <steve.glendinning@smsc.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-10 15:12:45 -08:00
Randy Dunlap
d3af0f048c [MTD] [NAND] remove excess kernel-doc notation
Delete extra kernel-doc notation for struct fields and function
parameters that don't exist:

Warning(include/linux/mtd/nand.h:428): Excess struct/union/enum/typedef member 'wq' description in 'nand_chip'
Warning(include/linux/mtd/nand.h:428): Excess struct/union/enum/typedef member 'datbuf' description in 'nand_chip'
Warning(include/linux/mtd/nand.h:428): Excess struct/union/enum/typedef member 'oobbuf' description in 'nand_chip'
Warning(include/linux/mtd/nand.h:428): Excess struct/union/enum/typedef member 'oobdirty' description in 'nand_chip'
Warning(include/linux/mtd/nand.h:428): Excess struct/union/enum/typedef member 'data_poi' description in 'nand_chip'
Warning(drivers/mtd/nand/nand_base.c:2527): Excess function parameter 'maxchips' description in 'nand_scan_tail'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2008-12-10 16:10:40 +00:00
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
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
David Woodhouse
c4956ed6fa Merge branch 'misc/mtd/sharpsl-nand' of git://git.kernel.org/pub/scm/linux/kernel/git/lumag/tosa-2.6 2008-12-10 15:49:12 +00:00
Mark Brown
cdc6936432 ALSA: Add support for mechanical jack insertion
Some systems support both mechanical and electrical jack detection,
allowing them to report that a jack is physically present but does
not have any functioning connections. Add a new jack type for these,
allowing user space to report faulty connections.

Thanks to Guillem Jover for the suggestion.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2008-12-10 15:10:44 +01:00
David Woodhouse
26cdb67c74 [MTD] Remove more strange u_intxx_t types
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2008-12-10 14:08:56 +00:00
David Woodhouse
3854be7712 [MTD] Remove strange u_int32_t types from FTL
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2008-12-10 14:06:42 +00:00
Adrian Hunter
69423d99fc [MTD] update internal API to support 64-bit device size
MTD internal API presently uses 32-bit values to represent
device size.  This patch updates them to 64-bits but leaves
the external API unchanged.  Extending the external API
is a separate issue for several reasons.  First, no one
needs it at the moment.  Secondly, whether the implementation
is done with IOCTLs, sysfs or both is still debated.  Thirdly
external API changes require the internal API to be accepted
first.

Note that although the MTD API will be able to support 64-bit
device sizes, existing drivers do not and are not required
to do so, although NAND base has been updated.

In general, changing from 32-bit to 64-bit values cause little
or no changes to the majority of the code with the following
exceptions:
    	- printk message formats
    	- division and modulus of 64-bit values
    	- NAND base support
	- 32-bit local variables used by mtdpart and mtdconcat
	- naughtily assuming one structure maps to another
	in MEMERASE ioctl

Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2008-12-10 13:37:21 +00:00
Robert Richter
e09373f22e ring_buffer: add remaining cpu functions to ring_buffer.h
These functions are not yet in ring_buffer.h though they seems to be
part of the API.

Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-10 14:20:17 +01:00