Commit Graph

15216 Commits

Author SHA1 Message Date
Adrian McMenamin
b233b28eac sh: maple: Support block reads and writes.
This patch updates the maple bus to support asynchronous block reads
and writes as well as generally improving the quality of the code and
supporting concurrency (all needed to support the Dreamcast visual
memory unit - a driver will also be posted for that).

Changes in the bus driver necessitate some changes in the two maple bus
input drivers that are currently in mainline.

As well as supporting block reads and writes this code clean up removes
some poor handling of locks, uses an atomic status variable to serialise
access to devices and more robusly handles the general performance
problems of the bus.

Signed-off-by: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-02-27 16:07:32 +09:00
Ingo Molnar
b342501cd3 sched: allow architectures to specify sched_clock_stable
Allow CONFIG_HAVE_UNSTABLE_SCHED_CLOCK architectures to still specify
that their sched_clock() implementation is reliable.

This will be used by x86 to switch on a faster sched_clock_cpu()
implementation on certain CPU types.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-26 21:20:22 +01:00
Ingo Molnar
4434e51564 Merge branches 'sched/cleanups', 'sched/urgent' and 'linus' into sched/core 2009-02-26 13:22:13 +01:00
Jens Axboe
1e42807918 block: reduce stack footprint of blk_recount_segments()
blk_recalc_rq_segments() requires a request structure passed in, which
we don't have from blk_recount_segments(). So the latter allocates one on
the stack, using > 400 bytes of stack for that. This can cause us to spill
over one page of stack from ext4 at least:

 0)     4560     400   blk_recount_segments+0x43/0x62
 1)     4160      32   bio_phys_segments+0x1c/0x24
 2)     4128      32   blk_rq_bio_prep+0x2a/0xf9
 3)     4096      32   init_request_from_bio+0xf9/0xfe
 4)     4064     112   __make_request+0x33c/0x3f6
 5)     3952     144   generic_make_request+0x2d1/0x321
 6)     3808      64   submit_bio+0xb9/0xc3
 7)     3744      48   submit_bh+0xea/0x10e
 8)     3696     368   ext4_mb_init_cache+0x257/0xa6a [ext4]
 9)     3328     288   ext4_mb_regular_allocator+0x421/0xcd9 [ext4]
10)     3040     160   ext4_mb_new_blocks+0x211/0x4b4 [ext4]
11)     2880     336   ext4_ext_get_blocks+0xb61/0xd45 [ext4]
12)     2544      96   ext4_get_blocks_wrap+0xf2/0x200 [ext4]
13)     2448      80   ext4_da_get_block_write+0x6e/0x16b [ext4]
14)     2368     352   mpage_da_map_blocks+0x7e/0x4b3 [ext4]
15)     2016     352   ext4_da_writepages+0x2ce/0x43c [ext4]
16)     1664      32   do_writepages+0x2d/0x3c
17)     1632     144   __writeback_single_inode+0x162/0x2cd
18)     1488      96   generic_sync_sb_inodes+0x1e3/0x32b
19)     1392      16   sync_sb_inodes+0xe/0x10
20)     1376      48   writeback_inodes+0x69/0xb3
21)     1328     208   balance_dirty_pages_ratelimited_nr+0x187/0x2f9
22)     1120     224   generic_file_buffered_write+0x1d4/0x2c4
23)      896     176   __generic_file_aio_write_nolock+0x35f/0x393
24)      720      80   generic_file_aio_write+0x6c/0xc8
25)      640      80   ext4_file_write+0xa9/0x137 [ext4]
26)      560     320   do_sync_write+0xf0/0x137
27)      240      48   vfs_write+0xb3/0x13c
28)      192      64   sys_write+0x4c/0x74
29)      128     128   system_call_fastpath+0x16/0x1b

Split the segment counting out into a __blk_recalc_rq_segments() helper
to avoid allocating an onstack request just for checking the physical
segment count.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-02-26 10:45:48 +01:00
Ingo Molnar
ecc25fbd6b Merge branches 'x86/apic', 'x86/defconfig', 'x86/memtest', 'x86/mm' and 'linus' into x86/core 2009-02-26 06:31:32 +01:00
Ingo Molnar
801c0be814 Merge branches 'x86/urgent' and 'x86/pat' into x86/core
Conflicts:
	arch/x86/include/asm/pat.h
2009-02-26 06:31:23 +01:00
Ingo Molnar
13b2eda64d Merge branch 'x86/urgent' into x86/core
Conflicts:
	arch/x86/mach-voyager/voyager_smp.c
2009-02-26 06:30:42 +01:00
Paul E. McKenney
a682604838 rcu: Teach RCU that idle task is not quiscent state at boot
This patch fixes a bug located by Vegard Nossum with the aid of
kmemcheck, updated based on review comments from Nick Piggin,
Ingo Molnar, and Andrew Morton.  And cleans up the variable-name
and function-name language.  ;-)

The boot CPU runs in the context of its idle thread during boot-up.
During this time, idle_cpu(0) will always return nonzero, which will
fool Classic and Hierarchical RCU into deciding that a large chunk of
the boot-up sequence is a big long quiescent state.  This in turn causes
RCU to prematurely end grace periods during this time.

This patch changes the rcutree.c and rcuclassic.c rcu_check_callbacks()
function to ignore the idle task as a quiescent state until the
system has started up the scheduler in rest_init(), introducing a
new non-API function rcu_idle_now_means_idle() to inform RCU of this
transition.  RCU maintains an internal rcu_idle_cpu_truthful variable
to track this state, which is then used by rcu_check_callback() to
determine if it should believe idle_cpu().

Because this patch has the effect of disallowing RCU grace periods
during long stretches of the boot-up sequence, this patch also introduces
Josh Triplett's UP-only optimization that makes synchronize_rcu() be a
no-op if num_online_cpus() returns 1.  This allows boot-time code that
calls synchronize_rcu() to proceed normally.  Note, however, that RCU
callbacks registered by call_rcu() will likely queue up until later in
the boot sequence.  Although rcuclassic and rcutree can also use this
same optimization after boot completes, rcupreempt must restrict its
use of this optimization to the portion of the boot sequence before the
scheduler starts up, given that an rcupreempt RCU read-side critical
section may be preeempted.

In addition, this patch takes Nick Piggin's suggestion to make the
system_state global variable be __read_mostly.

Changes since v4:

o	Changes the name of the introduced function and variable to
	be less emotional.  ;-)

Changes since v3:

o	WARN_ON(nr_context_switches() > 0) to verify that RCU
	switches out of boot-time mode before the first context
	switch, as suggested by Nick Piggin.

Changes since v2:

o	Created rcu_blocking_is_gp() internal-to-RCU API that
	determines whether a call to synchronize_rcu() is itself
	a grace period.

o	The definition of rcu_blocking_is_gp() for rcuclassic and
	rcutree checks to see if but a single CPU is online.

o	The definition of rcu_blocking_is_gp() for rcupreempt
	checks to see both if but a single CPU is online and if
	the system is still in early boot.

	This allows rcupreempt to again work correctly if running
	on a single CPU after booting is complete.

o	Added check to rcupreempt's synchronize_sched() for there
	being but one online CPU.

Tested all three variants both SMP and !SMP, booted fine, passed a short
rcutorture test on both x86 and Power.

Located-by: Vegard Nossum <vegard.nossum@gmail.com>
Tested-by: Vegard Nossum <vegard.nossum@gmail.com>
Tested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-26 04:08:14 +01:00
Tejun Heo
e317603694 percpu: fix too low alignment restriction on UP
UP __alloc_percpu() triggered WARN_ON_ONCE() if the requested
alignment is larger than that of unsigned long long, which is too
small for all the cacheline aligned allocations.  Bump it up to
SMP_CACHE_BYTES which kmalloc allocations generally guarantee.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Ingo Molnar <mingo@elte.hu>
2009-02-26 10:54:17 +09:00
Bartlomiej Zolnierkiewicz
8fed436841 ide: fix refcounting in device drivers
During host driver module removal del_gendisk() results in a final
put on drive->gendev and freeing the drive by drive_release_dev().

Convert device drivers from using struct kref to use struct device
so device driver's object holds reference on ->gendev and prevents
drive from prematurely going away.

Also fix ->remove methods to not erroneously drop reference on a
host driver by using only put_device() instead of ide*_put().

Reported-by: Stanislaw Gruszka <stf_xl@wp.pl>
Tested-by: Stanislaw Gruszka <stf_xl@wp.pl>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-02-25 20:28:24 +01:00
Ingo Molnar
2b9d1496e7 time: ntp: make 64-bit constants more robust
Impact: cleanup, no functionality changed

 - make PPM_SCALE an explicit s64 constant, to
   remove (s64) casts from usage sites.

kernel/time/ntp.o:

   text	   data	    bss	    dec	    hex	filename
   2536	    114	    136	   2786	    ae2	ntp.o.before
   2536	    114	    136	   2786	    ae2	ntp.o.after

md5:
   40a7728d1188aa18e83e21a81fa7b150  ntp.o.before.asm
   40a7728d1188aa18e83e21a81fa7b150  ntp.o.after.asm

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-25 18:38:15 +01:00
Linus Torvalds
60042600c5 Merge git://git.infradead.org/iommu-2.6
* git://git.infradead.org/iommu-2.6:
  intel-iommu: fix endless "Unknown DMAR structure type" loop
  VT-d: handle Invalidation Queue Error to avoid system hang
  intel-iommu: fix build error with INTR_REMAP=y and DMAR=n
2009-02-25 09:31:21 -08:00
Ingo Molnar
d2b0261506 alloc_percpu: fix UP build
Impact: build fix

the !SMP branch had a 'gfp' leftover:

 include/linux/percpu.h: In function '__alloc_percpu':
 include/linux/percpu.h:160: error: 'gfp' undeclared (first use in this function)
 include/linux/percpu.h:160: error: (Each undeclared identifier is reported only once
 include/linux/percpu.h:160: error: for each function it appears in.)

Use GFP_KERNEL like the SMP version does.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-25 14:38:12 +01:00
Venkatesh Pallipadi
17581ad812 gpu/drm, x86, PAT: PAT support for io_mapping_*
Make io_mapping_create_wc and io_mapping_free go through PAT to make sure
that there are no memory type aliases.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Eric Anholt <eric@anholt.net>
Cc: Keith Packard <keithp@keithp.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-25 13:09:52 +01:00
Venkatesh Pallipadi
4ab0d47d0a gpu/drm, x86, PAT: io_mapping_create_wc and resource_size_t
io_mapping_create_wc should take a resource_size_t parameter in place of
unsigned long. With unsigned long, there will be no way to map greater than 4GB
address in i386/32 bit.

On x86, greater than 4GB addresses cannot be mapped on i386 without PAE. Return
error for such a case.

Patch also adds a structure for io_mapping, that saves the base, size and
type on HAVE_ATOMIC_IOMAP archs, that can be used to verify the offset on
io_mapping_map calls.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Eric Anholt <eric@anholt.net>
Cc: Keith Packard <keithp@keithp.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-25 13:09:51 +01:00
Ingo Molnar
3255aa2eb6 x86, mm: pass in 'total' to __copy_from_user_*nocache()
Impact: cleanup, enable future change

Add a 'total bytes copied' parameter to __copy_from_user_*nocache(),
and update all the callsites.

The parameter is not used yet - architecture code can use it to
more intelligently decide whether the copy should be cached or
non-temporal.

Cc: Salman Qazi <sqazi@google.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-25 10:20:03 +01:00
David S. Miller
f11c179eea Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	drivers/net/wireless/orinoco/orinoco.c
2009-02-25 00:02:05 -08:00
Pablo Neira Ayuso
1ce85fe402 netlink: change nlmsg_notify() return value logic
This patch changes the return value of nlmsg_notify() as follows:

If NETLINK_BROADCAST_ERROR is set by any of the listeners and
an error in the delivery happened, return the broadcast error;
else if there are no listeners apart from the socket that
requested a change with the echo flag, return the result of the
unicast notification. Thus, with this patch, the unicast
notification is handled in the same way of a broadcast listener
that has set the NETLINK_BROADCAST_ERROR socket flag.

This patch is useful in case that the caller of nlmsg_notify()
wants to know the result of the delivery of a netlink notification
(including the broadcast delivery) and take any action in case
that the delivery failed. For example, ctnetlink can drop packets
if the event delivery failed to provide reliable logging and
state-synchronization at the cost of dropping packets.

This patch also modifies the rtnetlink code to ignore the return
value of rtnl_notify() in all callers. The function rtnl_notify()
(before this patch) returned the error of the unicast notification
which makes rtnl_set_sk_err() reports errors to all listeners. This
is not of any help since the origin of the change (the socket that
requested the echoing) notices the ENOBUFS error if the notification
fails and should resync itself.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-24 23:18:28 -08:00
David S. Miller
8b6f92b1bd Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-2.6 2009-02-24 13:49:05 -08:00
Ingo Molnar
0edcf8d692 Merge branch 'tj-percpu' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc into core/percpu
Conflicts:
	arch/x86/include/asm/pgtable.h
2009-02-24 21:52:45 +01:00
Ingo Molnar
a852cbfaaf Merge branches 'x86/acpi', 'x86/apic', 'x86/asm', 'x86/cleanups', 'x86/mm', 'x86/signal' and 'x86/urgent'; commit 'v2.6.29-rc6' into x86/core 2009-02-24 21:50:43 +01:00
Jean Delvare
cd97f39b7c i2c-dev: Clarify the unit of ioctl I2C_TIMEOUT
The unit in which user-space can set the bus timeout value is jiffies
for historical reasons (back when HZ was always 100.) This is however
not good because user-space doesn't know how long a jiffy lasts. The
timeout value should instead be set in a fixed time unit. Given the
original value of HZ, this unit should be 10 ms, for compatibility.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
2009-02-24 19:19:49 +01:00
Jan Engelhardt
d060ffc184 netfilter: install missing headers
iptables imports headers from (the unifdefed headers of a)
kernel tree, but some headers happened to not be installed.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-02-24 15:23:58 +01:00
David S. Miller
e70049b9e7 Merge branch 'master' of /home/davem/src/GIT/linux-2.6/ 2009-02-24 03:50:29 -08:00
Tejun Heo
8d408b4be3 percpu: give more latitude to arch specific first chunk initialization
Impact: more latitude for first percpu chunk allocation

The first percpu chunk serves the kernel static percpu area and may or
may not contain extra room for further dynamic allocation.
Initialization of the first chunk needs to be done before normal
memory allocation service is up, so it has its own init path -
pcpu_setup_static().

It seems archs need more latitude while initializing the first chunk
for example to take advantage of large page mapping.  This patch makes
the following changes to allow this.

* Define PERCPU_DYNAMIC_RESERVE to give arch hint about how much space
  to reserve in the first chunk for further dynamic allocation.

* Rename pcpu_setup_static() to pcpu_setup_first_chunk().

* Make pcpu_setup_first_chunk() much more flexible by fetching page
  pointer by callback and adding optional @unit_size, @free_size and
  @base_addr arguments which allow archs to selectively part of chunk
  initialization to their likings.

Signed-off-by: Tejun Heo <tj@kernel.org>
2009-02-24 11:57:21 +09:00
Tejun Heo
c0c0a29379 vmalloc: add @align to vm_area_register_early()
Impact: allow larger alignment for early vmalloc area allocation

Some early vmalloc users might want larger alignment, for example, for
custom large page mapping.  Add @align to vm_area_register_early().
While at it, drop docbook comment on non-existent @size.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
2009-02-24 11:57:21 +09:00
Tejun Heo
2d0aae4169 bootmem: reorder interface functions and add a missing one
Impact: cleanup and addition of missing interface wrapper

The interface functions in bootmem.h was ordered in not so orderly
manner.  Reorder them such that

* functions allocating the same area group together -
  ie. alloc_bootmem group and alloc_bootmem_low group.

* functions w/o node parameter come before the ones w/ node parameter.

* nopanic variants are immediately below their panicky counterparts.

While at it, add alloc_bootmem_pages_node_nopanic() which was missing.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Johannes Weiner <hannes@saeurebad.de>
2009-02-24 11:57:21 +09:00
Tejun Heo
c132937556 bootmem: clean up arch-specific bootmem wrapping
Impact: cleaner and consistent bootmem wrapping

By setting CONFIG_HAVE_ARCH_BOOTMEM_NODE, archs can define
arch-specific wrappers for bootmem allocation.  However, this is done
a bit strangely in that only the high level convenience macros can be
changed while lower level, but still exported, interface functions
can't be wrapped.  This not only is messy but also leads to strange
situation where alloc_bootmem() does what the arch wants it to do but
the equivalent __alloc_bootmem() call doesn't although they should be
able to be used interchangeably.

This patch updates bootmem such that archs can override / wrap the
backend function - alloc_bootmem_core() instead of the highlevel
interface functions to allow simpler and consistent wrapping.  Also,
HAVE_ARCH_BOOTMEM_NODE is renamed to HAVE_ARCH_BOOTMEM.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Johannes Weiner <hannes@saeurebad.de>
2009-02-24 11:57:20 +09:00
Linus Torvalds
d38e84ee39 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
  netns: fix double free at netns creation
  veth : add the set_mac_address capability
  sunlance: Beyond ARRAY_SIZE of ib->btx_ring
  sungem: another error printed one too early
  ISDN: fix sc/shmem printk format warning
  SMSC: timeout reaches -1
  smsc9420: handle magic field of ethtool_eeprom
  sundance: missing parentheses?
  smsc9420: fix another postfixed timeout
  wimax/i2400m: driver loads firmware v1.4 instead of v1.3
  vlan: Update skb->mac_header in __vlan_put_tag().
  cxgb3: Add support for PCI ID 0x35.
  tcp: remove obsoleted comment about different passes
  TG3: &&/|| confusion
  ATM: misplaced parentheses?
  net/mv643xx: don't disable the mib timer too early and lock properly
  net/mv643xx: use GFP_ATOMIC while atomic
  atl1c: Atheros L1C Gigabit Ethernet driver
  net: Kill skb_truesize_check(), it only catches false-positives.
  net: forcedeth: Fix wake-on-lan regression
2009-02-23 14:36:05 -08:00
David Rientjes
3b89d7d881 slub: move min_partial to struct kmem_cache
Although it allows for better cacheline use, it is unnecessary to save a
copy of the cache's min_partial value in each kmem_cache_node.

Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
2009-02-23 12:05:41 +02:00
Benjamin Herrenschmidt
35f88e6b06 Merge commit 'ftrace/function-graph' into next 2009-02-23 10:47:23 +11:00
Ingo Molnar
fc6fc7f1b1 Merge branch 'linus' into x86/apic
Conflicts:
	arch/x86/mach-default/setup.c

Semantic conflict resolution:
	arch/x86/kernel/setup.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-22 20:05:19 +01:00
Rafael J. Wysocki
770824bdc4 PM: Split up sysdev_[suspend|resume] from device_power_[down|up]
Move the sysdev_suspend/resume from the callee to the callers, with
no real change in semantics, so that we can rework the disabling of
interrupts during suspend/hibernation.

This is based on an earlier patch from Linus.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-22 10:33:44 -08:00
Alexander Clouter
9c3c133b1e hwrng: timeriomem - New driver
Some hardware platforms, the TS-7800[1] is one for example, can
supply the kernel with an entropy source, albeit a slow one for
TS-7800 users, by just reading a particular IO address.  This
source must not be read above a certain rate otherwise the quality
suffers.

The driver is then hooked into by calling
platform_device_(register|add|del) passing a structure similar to:
------
static struct timeriomem_rng_data ts78xx_ts_rng_data = {
        .address        = (u32 *__iomem) TS_RNG,
        .period         = 1000000, /* one second */
};

static struct platform_device ts78xx_ts_rng_device = {
        .name           = "timeriomem_rng",
        .id             = -1,
        .dev            = {
                .platform_data  = &ts78xx_ts_rng_data,
        },
        .num_resources  = 0,
};
------

[1] http://www.embeddedarm.com/products/board-detail.php?product=TS-7800

Signed-off-by: Alexander Clouter <alex@digriz.org.uk>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-02-22 12:03:56 +08:00
Linus Torvalds
adfafefd10 Merge branch 'hibernate'
* hibernate:
  PM: Fix suspend_console and resume_console to use only one semaphore
  PM: Wait for console in resume
  PM: Fix pm_notifiers during user mode hibernation
  swsusp: clean up shrink_all_zones()
  swsusp: dont fiddle with swappiness
  PM: fix build for CONFIG_PM unset
  PM/hibernate: fix "swap breaks after hibernation failures"
  PM/resume: wait for device probing to finish
  Consolidate driver_probe_done() loops into one place
2009-02-21 14:17:26 -08:00
Arjan van de Ven
216773a787 Consolidate driver_probe_done() loops into one place
there's a few places that currently loop over driver_probe_done(), and
I'm about to add another one. This patch abstracts it into a helper
to reduce duplication.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Len Brown <lenb@kernel.org>
Acked-by: Greg KH <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-21 14:17:17 -08:00
Mauro Carvalho Chehab
b6adea334c 8250: fix boot hang with serial console when using with Serial Over Lan port
Intel 8257x Ethernet boards have a feature called Serial Over Lan.

This feature works by emulating a serial port, and it is detected by
kernel as a normal 8250 port.  However, this emulation is not perfect, as
also noticed on changeset 7500b1f602.

Before this patch, the kernel were trying to check if the serial TX is
capable of work using IRQ's.

This were done with a code similar this:

        serial_outp(up, UART_IER, UART_IER_THRI);
        lsr = serial_in(up, UART_LSR);
        iir = serial_in(up, UART_IIR);
        serial_outp(up, UART_IER, 0);

        if (lsr & UART_LSR_TEMT && iir & UART_IIR_NO_INT)
		up->bugs |= UART_BUG_TXEN;

This works fine for other 8250 ports, but, on 8250-emulated SoL port, the
chip is a little lazy to down UART_IIR_NO_INT at UART_IIR register.

Due to that, UART_BUG_TXEN is sometimes enabled.  However, as TX IRQ keeps
working, and the TX polling is now enabled, the driver miss-interprets the
IRQ received later, hanging up the machine until a key is pressed at the
serial console.

This is the 6 version of this patch.  Previous versions were trying to
introduce a large enough delay between serial_outp and serial_in(up,
UART_IIR), but not taking forever.  However, the needed delay couldn't be
safely determined.

At the experimental tests, a delay of 1us solves most of the cases, but
still hangs sometimes.  Increasing the delay to 5us was better, but still
doesn't solve.  A very high delay of 50 ms seemed to work every time.

However, poking around with delays and pray for it to be enough doesn't
seem to be a good approach, even for a quirk.

So, instead of playing with random large arbitrary delays, let's just
disable UART_BUG_TXEN for all SoL ports.

[akpm@linux-foundation.org: fix warnings]
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-20 17:57:50 -08:00
Michael Buesch
01b24fee28 spi_bitbang: add more lowlevel function documentation
This adds more documentation of the lowlevel API to avoid future bugs.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-20 17:57:49 -08:00
Johannes Weiner
3ef0e5ba46 slab: introduce kzfree()
kzfree() is a wrapper for kfree() that additionally zeroes the underlying
memory before releasing it to the slab allocator.

Currently there is code which memset()s the memory region of an object
before releasing it back to the slab allocator to make sure
security-sensitive data are really zeroed out after use.

These callsites can then just use kzfree() which saves some code, makes
users greppable and allows for a stupid destructor that isn't necessarily
aware of the actual object size.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Matt Mackall <mpm@selenic.com>
Acked-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-20 17:57:48 -08:00
Ingo Molnar
b18018126f x86, mm, kprobes: fault.c, simplify notify_page_fault()
Impact: cleanup

Remove an #ifdef from notify_page_fault(). The function still
compiles to nothing in the !CONFIG_KPROBES case.

Introduce kprobes_built_in() and kprobe_fault_handler() helpers
to allow this - they returns 0 if !CONFIG_KPROBES.

No code changed:

   text	   data	    bss	    dec	    hex	filename
   4618	     32	     24	   4674	   1242	fault.o.before
   4618	     32	     24	   4674	   1242	fault.o.after

Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-21 00:09:42 +01:00
Ingo Molnar
b814d41f09 x86, mm: fault.c, simplify kmmio_fault()
Impact: cleanup

Remove an #ifdef from kmmio_fault() - we can do this by
providing default implementations for is_kmmio_active()
and kmmio_handler(). The compiler optimizes it all away
in the !CONFIG_MMIOTRACE case.

Also, while at it, clean up mmiotrace.h a bit:

 - standard header guards
 - standard vertical spaces for structure definitions

No code changed (both with mmiotrace on and off in the config):

   text	   data	    bss	    dec	    hex	filename
   2947	     12	     12	   2971	    b9b	fault.o.before
   2947	     12	     12	   2971	    b9b	fault.o.after

Cc: Pekka Paalanen <pq@iki.fi>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-21 00:09:42 +01:00
Ingo Molnar
3b6f7b9beb Merge branch 'x86/urgent' into x86/core 2009-02-20 17:40:43 +01:00
Pekka Enberg
51735a7ca6 SLUB: Do not pass 8k objects through to the page allocator
Increase the maximum object size in SLUB so that 8k objects are not
passed through to the page allocator anymore. The network stack uses 8k
objects for performance critical operations.

The patch is motivated by a SLAB vs. SLUB regression in the netperf
benchmark. The problem is that the kfree(skb->head) call in
skb_release_data() that is subject to page allocator pass-through as the
size passed to __alloc_skb() is larger than 4 KB in this test.

As explained by Yanmin Zhang:

  I use 2.6.29-rc2 kernel to run netperf UDP-U-4k CPU_NUM client/server
  pair loopback testing on x86-64 machines. Comparing with SLUB, SLAB's
  result is about 2.3 times of SLUB's. After applying the reverting patch,
  the result difference between SLUB and SLAB becomes 1% which we might
  consider as fluctuation.

[ penberg@cs.helsinki.fi: fix oops in kmalloc() ]
Reported-by: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
Tested-by: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
Signed-off-by: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
2009-02-20 12:25:47 +02:00
Christoph Lameter
ffadd4d0fe SLUB: Introduce and use SLUB_MAX_SIZE and SLUB_PAGE_SHIFT constants
As a preparational patch to bump up page allocator pass-through threshold,
introduce two new constants SLUB_MAX_SIZE and SLUB_PAGE_SHIFT and convert
mm/slub.c to use them.

Reported-by: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
Tested-by: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
Signed-off-by: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
2009-02-20 12:22:44 +02:00
Adam Nielsen
268cb38e18 netfilter: x_tables: add LED trigger target
Kernel module providing implementation of LED netfilter target.  Each
instance of the target appears as a led-trigger device, which can be
associated with one or more LEDs in /sys/class/leds/

Signed-off-by: Adam Nielsen <a.nielsen@shikadi.net>
Acked-by: Richard Purdie <rpurdie@linux.intel.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-02-20 10:55:14 +01:00
Stephen Hemminger
784544739a netfilter: iptables: lock free counters
The reader/writer lock in ip_tables is acquired in the critical path of
processing packets and is one of the reasons just loading iptables can cause
a 20% performance loss. The rwlock serves two functions:

1) it prevents changes to table state (xt_replace) while table is in use.
   This is now handled by doing rcu on the xt_table. When table is
   replaced, the new table(s) are put in and the old one table(s) are freed
   after RCU period.

2) it provides synchronization when accesing the counter values.
   This is now handled by swapping in new table_info entries for each cpu
   then summing the old values, and putting the result back onto one
   cpu.  On a busy system it may cause sampling to occur at different
   times on each cpu, but no packet/byte counts are lost in the process.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>

Sucessfully tested on my dual quad core machine too, but iptables only (no ipv6 here)
BTW, my new "tbench 8" result is 2450 MB/s, (it was 2150 MB/s not so long ago)

Acked-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-02-20 10:35:32 +01:00
Pablo Neira Ayuso
be0c22a46c netlink: add NETLINK_BROADCAST_ERROR socket option
This patch adds NETLINK_BROADCAST_ERROR which is a netlink
socket option that the listener can set to make netlink_broadcast()
return errors in the delivery to the caller. This option is useful
if the caller of netlink_broadcast() do something with the result
of the message delivery, like in ctnetlink where it drops a network
packet if the event delivery failed, this is used to enable reliable
logging and state-synchronization. If this socket option is not set,
netlink_broadcast() only reports ESRCH errors and silently ignore
ENOBUFS errors, which is what most netlink_broadcast() callers
should do.

This socket option is based on a suggestion from Patrick McHardy.
Patrick McHardy can exchange this patch for a beer from me ;).

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-20 01:01:08 -08:00
Santwona Behera
59089d8d16 ethtool: Add RX pkt classification interface
Signed-off-by: Santwona Behera <santwona.behera@sun.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-20 00:58:13 -08:00
Tejun Heo
fbf59bc9d7 percpu: implement new dynamic percpu allocator
Impact: new scalable dynamic percpu allocator which allows dynamic
        percpu areas to be accessed the same way as static ones

Implement scalable dynamic percpu allocator which can be used for both
static and dynamic percpu areas.  This will allow static and dynamic
areas to share faster direct access methods.  This feature is optional
and enabled only when CONFIG_HAVE_DYNAMIC_PER_CPU_AREA is defined by
arch.  Please read comment on top of mm/percpu.c for details.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
2009-02-20 16:29:08 +09:00
Tejun Heo
8fc4898500 vmalloc: add un/map_kernel_range_noflush()
Impact: two more public map/unmap functions

Implement map_kernel_range_noflush() and unmap_kernel_range_noflush().
These functions respectively map and unmap address range in kernel VM
area but doesn't do any vcache or tlb flushing.  These will be used by
new percpu allocator.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
2009-02-20 16:29:08 +09:00