Commit Graph

17905 Commits

Author SHA1 Message Date
Greg Banks
fca4217c5b knfsd: reply cache cleanups
Make REQHASH() an inline function.  Rename hash_list to cache_hash.
Fix an obsolete comment.

Signed-off-by: Greg Banks <gnb@sgi.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-05-27 14:14:02 -04:00
Pablo Neira Ayuso
a17c859849 netfilter: conntrack: add support for DCCP handshake sequence to ctnetlink
This patch adds CTA_PROTOINFO_DCCP_HANDSHAKE_SEQ that exposes
the u64 handshake sequence number to user-space.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-05-27 17:50:35 +02:00
Sebastian Andrzej Siewior
cbf806dd93 Input: ucb1400 - move static function from header into core
it's a little too large for static line.
The ts is currently the only mainline user but Marek Vasut claims that
there is a battery driver in an ARM tree which also needs this function.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2009-05-27 06:25:05 -07:00
Herbert Xu
a5b1cf288d gro: Avoid unnecessary comparison after skb_gro_header
For the overwhelming majority of cases, skb_gro_header's return
value cannot be NULL.  Yet we must check it because of its current
form.  This patch splits it up into multiple functions in order
to avoid this.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-27 03:26:01 -07:00
Herbert Xu
7489594cb2 gro: Optimise length comparison in skb_gro_header
By caching frag0_len, we can avoid checking both frag0 and the
length separately in skb_gro_header.  This helps as skb_gro_header
is called four times per packet which amounts to a few million
times at 10Gb/s.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-27 03:26:01 -07:00
Herbert Xu
78d3fd0b7d gro: Only use skb_gro_header for completely non-linear packets
Currently skb_gro_header is used for packets which put the hardware
header in skb->data with the rest in frags.  Since the drivers that
need this optimisation all provide completely non-linear packets,
we can gain extra optimisations by only performing the frag0
optimisation for completely non-linear packets.

In particular, we can simply test frag0 (instead of skb_headlen)
to see whether the optimisation is in force.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-27 03:25:57 -07:00
Herbert Xu
78a478d0ef gro: Inline skb_gro_header and cache frag0 virtual address
The function skb_gro_header is called four times per packet which
quickly adds up at 10Gb/s.  This patch inlines it to allow better
optimisations.

Some architectures perform multiplication for page_address, which
is done by each skb_gro_header invocation.  This patch caches that
value in skb->cb to avoid the unnecessary multiplications.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-27 03:25:55 -07:00
David S. Miller
8e401eccd3 phy: Eliminate references to BUS_ID_SIZE.
Just use the constant 20 to keep things working.

If someone is so motivated, this can be converted over to
dynamic strings.  I tried and it's a lot of work.

But for now this is good enough.

Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-26 21:16:25 -07:00
Steven Rostedt
0f4fc29dd6 tracing: add __print_symbolic to trace events
This patch adds __print_symbolic which is similar to __print_flags but
works for an enumeration type instead. That is, there is only a one to one
mapping between the values and the symbols. When a match is made, then
it is printed, otherwise the hex value is outputed.

[ Impact: add interface for showing symbol names in events ]

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-05-26 20:31:50 +02:00
Steven Rostedt
be74b73a57 tracing: add __print_flags for events
Developers have been asking for the ability in the ftrace event tracer
to display names of bits in a flags variable.

Instead of printing out c2, it would be easier to read FOO|BAR|GOO,
assuming that FOO is bit 1, BAR is bit 6 and GOO is bit 7.

Some examples where this would be useful are the state flags in a context
switch, kmalloc flags, and even permision flags in accessing files.

[
  v2 changes include:

  Frederic Weisbecker's idea of using a mask instead of bits,
  thus we can output GFP_KERNEL instead of GPF_WAIT|GFP_IO|GFP_FS.

  Li Zefan's idea of allowing the caller of __print_flags to add their
  own delimiter (or no delimiter) where we can get for file permissions
  rwx instead of r|w|x.
]

[
  v3 changes:

   Christoph Hellwig's idea of using an array instead of va_args.
]

[ Impact: better displaying of flags in trace output ]

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-05-26 20:25:22 +02:00
David Woodhouse
b90cf6681f [MTD] Remove option for add_mtd_partitions() to not register partitions.
This breaks the dilnetpc map driver, but it could be fixed not to use
that option. We want to simplify the partition handling, and this is a
step towards that.

Remove superfluous 'index' field from private struct mtd_part too, while
we're at it.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2009-05-26 16:45:44 +01:00
Eric Dumazet
08baf56108 net: txq_trans_update() helper
We would like to get rid of netdev->trans_start = jiffies; that about all net
drivers have to use in their start_xmit() function, and use txq->trans_start
instead.

This can be done generically in core network, as suggested by David.

Some devices, (particularly loopback) dont need trans_start update, because
they dont have transmit watchdog. We could add a new device flag, or rely
on fact that txq->tran_start can be updated is txq->xmit_lock_owner is
different than -1. Use a helper function to hide our choice.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-25 22:58:01 -07:00
Ingo Molnar
0127c3ea08 perf_counter: fix warning & lockup
- remove bogus warning
 - fix wakeup from NMI path lockup
 - also fix up whitespace noise in perf_counter.h

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <20090525153931.703093461@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-25 22:02:23 +02:00
Peter Zijlstra
a78ac32587 perf_counter: Generic per counter interrupt throttle
Introduce a generic per counter interrupt throttle.

This uses the perf_counter_overflow() quick disable to throttle a specific
counter when its going too fast when a pmu->unthrottle() method is provided
which can undo the quick disable.

Power needs to implement both the quick disable and the unthrottle method.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <20090525153931.703093461@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-25 21:41:12 +02:00
Peter Zijlstra
48e22d56ec perf_counter: x86: Remove interrupt throttle
remove the x86 specific interrupt throttle

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <20090525153931.616671838@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-25 21:41:12 +02:00
Jozsef Kadlecsik
bfcaa50270 netfilter: nf_ct_tcp: fix accepting invalid RST segments
Robert L Mathews discovered that some clients send evil TCP RST segments,
which are accepted by netfilter conntrack but discarded by the
destination. Thus the conntrack entry is destroyed but the destination
retransmits data until timeout.

The same technique, i.e. sending properly crafted RST segments, can easily
be used to bypass connlimit/connbytes based restrictions (the sample
script written by Robert can be found in the netfilter mailing list
archives).

The patch below adds a new flag and new field to struct ip_ct_tcp_state so
that checking RST segments can be made more strict and thus TCP conntrack
can catch the invalid ones: the RST segment is accepted only if its
sequence number higher than or equal to the highest ack we seen from the
other direction. (The last_ack field cannot be reused because it is used
to catch resent packets.)

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-05-25 17:23:15 +02:00
Peter Zijlstra
6ab423e0ea perf_counter: Propagate inheritance failures down the fork() path
Fail fork() when we fail inheritance for some reason (-ENOMEM most likely).

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <20090525124600.324656474@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-25 14:55:01 +02:00
Peter Zijlstra
e527ea312f perf_counter: Remove unused ABI bits
extra_config_len isn't used for anything, remove it.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <20090525124600.116035832@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-25 14:55:00 +02:00
Alexander Beregalov
e3804cbebb net: remove COMPAT_NET_DEV_OPS
All drivers are already converted to new net_device_ops API
and nobody uses old API anymore.

Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-25 01:53:53 -07:00
Andreas Eversberg
daebafed7f mISDN: Added PCI ID for new Junghanns.net Single E1 cards.
The new ID is validated by Cologne Chip.
LEDs control is also supported.

Signed-off-by: Andreas Eversberg <andreas@eversberg.eu>
Signed-off-by: Karsten Keil <keil@b1-systems.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-25 00:56:56 -07:00
Karsten Keil
eac74af9b5 mISDN: Cleanup debug messages
This patch make debug printk's KERN_DEBUG and also fix some
codestyle issues.

Signed-off-by: Karsten Keil <keil@b1-systems.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-25 00:55:45 -07:00
Andreas Eversberg
7245a2fe3c mISDN: Add PCI ID for Junghanns 8S card
new id for HFC-8S

Signed-off-by: Andreas Eversberg <andreas@eversberg.eu>
Signed-off-by: Karsten Keil <keil@b1-systems.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-25 00:55:45 -07:00
Karsten Keil
db9bb63a1b mISDN: Add XHFC support for embedded Speech-Design board to hfcmulti
New version without emulating arch specific stuff for the other
architectures, the special IO and init functions for the 8xx
microcontroller are in a separate include file.

Signed-off-by: Andreas Eversberg <andreas@eversberg.eu>
Signed-off-by: Karsten Keil <keil@b1-systems.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-25 00:55:30 -07:00
Andreas Eversberg
e73f6b2260 mISDN: Added layer-1-hold feature
Add IMHOLD_L1 ioctl.
The feature will be disabled on closing.

Signed-off-by: Andreas Eversberg <andreas@eversberg.eu>
Signed-off-by: Karsten Keil <keil@b1-systems.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-25 00:51:33 -07:00
Andreas Eversberg
7cfa153dd7 mISDN: Echo canceler now gets delay information from hardware
Added tx-fifo information for calculation of current delay to sync tx and rx
streams for echo canceler.

Signed-off-by: Andreas Eversberg <andreas@eversberg.eu>
Signed-off-by: Karsten Keil <keil@b1-systems.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-25 00:51:31 -07:00
Andreas Eversberg
7df3bb8f59 mISDN: Add watchdog functionality to hfcmulti driver
This patch was made by Titus Moldovan and provides IOCTL functions for enabling
and disabling the controller's built in watchdog. The use is optional.

Signed-off-by: Andreas Eversberg <andreas@eversberg.eu>
Signed-off-by: Karsten Keil <keil@b1-systems.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-25 00:51:18 -07:00
David S. Miller
45ea4ea2af Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next-2.6 2009-05-25 00:38:24 -07:00
Peter Zijlstra
475c557973 perf_counter: Remove perf_counter_context::nr_enabled
now that pctrl() no longer disables other people's counters,
remove the PMU cache code that deals with that.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <20090523163013.032998331@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-24 08:24:30 +02:00
Peter Zijlstra
082ff5a276 perf_counter: Change pctrl() behaviour
Instead of en/dis-abling all counters acting on a particular
task, en/dis- able all counters we created.

[ v2: fix crash on first counter enable ]

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <20090523163012.916937244@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-24 08:24:08 +02:00
Peter Zijlstra
fccc714b31 perf_counter: Sanitize counter->mutex
s/counter->mutex/counter->child_mutex/ and make sure its only
used to protect child_list.

The usage in __perf_counter_exit_task() doesn't appear to be
problematic since ctx->mutex also covers anything related to fd
tear-down.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <20090523163012.533186528@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-23 19:37:45 +02:00
Peter Zijlstra
e220d2dcb9 perf_counter: Fix dynamic irq_period logging
We call perf_adjust_freq() from perf_counter_task_tick() which
is is called under the rq->lock causing lock recursion.
However, it's no longer required to be called under the
rq->lock, so remove it from under it.

Also, fix up some related comments.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <20090523163012.476197912@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-23 19:37:44 +02:00
Henrik Rydberg
df391e0eda Input: multitouch - add tracking ID to the protocol
There are a few multi-touch devices that support finger tracking
well in hardware, Stantum being the prime example. By exposing the
tracking ID in the MT protocol, evdev bandwidth and cpu usage in
user space can be reduced.

This patch adds the ABS_MT_TRACKING_ID to the MT protocol.

Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Tested-by: Stéphane Chatty <chatty@enac.fr>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2009-05-23 09:53:18 -07:00
Martin K. Petersen
c72758f337 block: Export I/O topology for block devices and partitions
To support devices with physical block sizes bigger than 512 bytes we
need to ensure proper alignment.  This patch adds support for exposing
I/O topology characteristics as devices are stacked.

  logical_block_size is the smallest unit the device can address.

  physical_block_size indicates the smallest I/O the device can write
  without incurring a read-modify-write penalty.

  The io_min parameter is the smallest preferred I/O size reported by
  the device.  In many cases this is the same as the physical block
  size.  However, the io_min parameter can be scaled up when stacking
  (RAID5 chunk size > physical block size).

  The io_opt characteristic indicates the optimal I/O size reported by
  the device.  This is usually the stripe width for arrays.

  The alignment_offset parameter indicates the number of bytes the start
  of the device/partition is offset from the device's natural alignment.
  Partition tools and MD/DM utilities can use this to pad their offsets
  so filesystems start on proper boundaries.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-22 23:22:55 +02:00
Martin K. Petersen
025146e13b block: Move queue limits to an embedded struct
To accommodate stacking drivers that do not have an associated request
queue we're moving the limits to a separate, embedded structure.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-22 23:22:55 +02:00
Martin K. Petersen
ae03bf639a block: Use accessor functions for queue limits
Convert all external users of queue limits to using wrapper functions
instead of poking the request queue variables directly.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-22 23:22:54 +02:00
Martin K. Petersen
e1defc4ff0 block: Do away with the notion of hardsect_size
Until now we have had a 1:1 mapping between storage device physical
block size and the logical block sized used when addressing the device.
With SATA 4KB drives coming out that will no longer be the case.  The
sector size will be 4KB but the logical block size will remain
512-bytes.  Hence we need to distinguish between the physical block size
and the logical ditto.

This patch renames hardsect_size to logical_block_size.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-22 23:22:54 +02:00
Jens Axboe
9bd7de51ee Merge branch 'master' into for-2.6.31
Conflicts:
	drivers/ide/ide-io.c

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-22 20:28:35 +02:00
Jens Axboe
e4b636366c Merge branch 'master' into for-2.6.31
Conflicts:
	drivers/block/hd.c
	drivers/block/mg_disk.c

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-22 20:25:34 +02:00
Zhu Yi
e31a16d6f6 wireless: move some utility functions from mac80211 to cfg80211
The patch moves some utility functions from mac80211 to cfg80211.
Because these functions are doing generic 802.11 operations so they
are not mac80211 specific. The moving allows some fullmac drivers
to be also benefit from these utility functions.

Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: Samuel Ortiz <samuel.ortiz@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-05-22 14:06:02 -04:00
Linus Torvalds
5ae115af1d Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6:
  via82cxxx: Add VIA VX855 PCI Device ID
  ide: report timeouts in ide_busy_sleep()
  ide: improve failed opcode reporting
  ide: fix printk() levels in ide_dump_ata[pi]_error()
  ide: fix OOPS during ide-cd error recovery
  ide: fix 40-wire cable detection for TSST SH-S202* ATAPI devices (v2)
2009-05-22 08:22:39 -07:00
Bartlomiej Zolnierkiewicz
4c9773ed79 Merge branch 'for-linus' into for-next 2009-05-22 17:10:55 +02:00
Harald Welte
5993856e53 via82cxxx: Add VIA VX855 PCI Device ID
This patch adds the PCI Device ID 0xc409 to the PCI ID table of via82cxxx.c,
as well as the 0x8409 south bridge ID.

This is required to make the IDE driver work on the VX855/VX875 integrated
chipset.

Signed-off-by: Harald Welte <HaraldWelte@viatech.com>
Cc: Joseph Chan <JosephChan@via.com.tw>
Cc: Bruce Chang <BruceChang@via.com.tw>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-05-22 16:23:39 +02:00
Bartlomiej Zolnierkiewicz
28ee9bc5cc ide: report timeouts in ide_busy_sleep()
* change 'hwif' argument to 'drive'
* report an error on timeout

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-05-22 16:23:38 +02:00
Ingo Molnar
910431c7f2 perf_counter: fix !PERF_COUNTERS build failure
Update the !CONFIG_PERF_COUNTERS prototype too, for
perf_counter_task_sched_out().

[ Impact: build fix ]

Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <18966.10666.517218.332164@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-22 12:33:14 +02:00
Paul Mackerras
564c2b210a perf_counter: Optimize context switch between identical inherited contexts
When monitoring a process and its descendants with a set of inherited
counters, we can often get the situation in a context switch where
both the old (outgoing) and new (incoming) process have the same set
of counters, and their values are ultimately going to be added together.
In that situation it doesn't matter which set of counters are used to
count the activity for the new process, so there is really no need to
go through the process of reading the hardware counters and updating
the old task's counters and then setting up the PMU for the new task.

This optimizes the context switch in this situation.  Instead of
scheduling out the perf_counter_context for the old task and
scheduling in the new context, we simply transfer the old context
to the new task and keep using it without interruption.  The new
context gets transferred to the old task.  This means that both
tasks still have a valid perf_counter_context, so no special case
is introduced when the old task gets scheduled in again, either on
this CPU or another CPU.

The equivalence of contexts is detected by keeping a pointer in
each cloned context pointing to the context it was cloned from.
To cope with the situation where a context is changed by adding
or removing counters after it has been cloned, we also keep a
generation number on each context which is incremented every time
a context is changed.  When a context is cloned we take a copy
of the parent's generation number, and two cloned contexts are
equivalent only if they have the same parent and the same
generation number.  In order that the parent context pointer
remains valid (and is not reused), we increment the parent
context's reference count for each context cloned from it.

Since we don't have individual fds for the counters in a cloned
context, the only thing that can make two clones of a given parent
different after they have been cloned is enabling or disabling all
counters with prctl.  To account for this, we keep a count of the
number of enabled counters in each context.  Two contexts must have
the same number of enabled counters to be considered equivalent.

Here are some measurements of the context switch time as measured with
the lat_ctx benchmark from lmbench, comparing the times obtained with
and without this patch series:

		-----Unmodified-----		With this patch series
Counters:	none	2 HW	4H+4S	none	2 HW	4H+4S

2 processes:
Average		3.44	6.45	11.24	3.12	3.39	3.60
St dev		0.04	0.04	0.13	0.05	0.17	0.19

8 processes:
Average		6.45	8.79	14.00	5.57	6.23	7.57
St dev		1.27	1.04	0.88	1.42	1.46	1.42

32 processes:
Average		5.56	8.43	13.78	5.28	5.55	7.15
St dev		0.41	0.47	0.53	0.54	0.57	0.81

The numbers are the mean and standard deviation of 20 runs of
lat_ctx.  The "none" columns are lat_ctx run directly without any
counters.  The "2 HW" columns are with lat_ctx run under perfstat,
counting cycles and instructions.  The "4H+4S" columns are lat_ctx run
under perfstat with 4 hardware counters and 4 software counters
(cycles, instructions, cache references, cache misses, task
clock, context switch, cpu migrations, and page faults).

[ Impact: performance optimization of counter context-switches ]

Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <18966.10666.517218.332164@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-22 12:18:20 +02:00
Paul Mackerras
a63eaf34ae perf_counter: Dynamically allocate tasks' perf_counter_context struct
This replaces the struct perf_counter_context in the task_struct with
a pointer to a dynamically allocated perf_counter_context struct.  The
main reason for doing is this is to allow us to transfer a
perf_counter_context from one task to another when we do lazy PMU
switching in a later patch.

This has a few side-benefits: the task_struct becomes a little smaller,
we save some memory because only tasks that have perf_counters attached
get a perf_counter_context allocated for them, and we can remove the
inclusion of <linux/perf_counter.h> in sched.h, meaning that we don't
end up recompiling nearly everything whenever perf_counter.h changes.

The perf_counter_context structures are reference-counted and freed
when the last reference is dropped.  A context can have references
from its task and the counters on its task.  Counters can outlive the
task so it is possible that a context will be freed well after its
task has exited.

Contexts are allocated on fork if the parent had a context, or
otherwise the first time that a per-task counter is created on a task.
In the latter case, we set the context pointer in the task struct
locklessly using an atomic compare-and-exchange operation in case we
raced with some other task in creating a context for the subject task.

This also removes the task pointer from the perf_counter struct.  The
task pointer was not used anywhere and would make it harder to move a
context from one task to another.  Anything that needed to know which
task a counter was attached to was already using counter->ctx->task.

The __perf_counter_init_context function moves up in perf_counter.c
so that it can be called from find_get_context, and now initializes
the refcount, but is otherwise unchanged.

We were potentially calling list_del_counter twice: once from
__perf_counter_exit_task when the task exits and once from
__perf_counter_remove_from_context when the counter's fd gets closed.
This adds a check in list_del_counter so it doesn't do anything if
the counter has already been removed from the lists.

Since perf_counter_task_sched_in doesn't do anything if the task doesn't
have a context, and leaves cpuctx->task_ctx = NULL, this adds code to
__perf_install_in_context to set cpuctx->task_ctx if necessary, i.e. in
the case where the current task adds the first counter to itself and
thus creates a context for itself.

This also adds similar code to __perf_counter_enable to handle a
similar situation which can arise when the counters have been disabled
using prctl; that also leaves cpuctx->task_ctx = NULL.

[ Impact: refactor counter context management to prepare for new feature ]

Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <18966.10075.781053.231153@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-22 12:18:19 +02:00
James Morris
2c9e703c61 Merge branch 'master' into next
Conflicts:
	fs/exec.c

Removed IMA changes (the IMA checks are now performed via may_open()).

Signed-off-by: James Morris <jmorris@namei.org>
2009-05-22 18:40:59 +10:00
Paul Mundt
5f8371cec9 Merge branches 'sh/stable-updates' and 'sh/sparseirq' 2009-05-22 13:29:37 +09:00
Neil Horman
4ea7e38696 dropmon: add ability to detect when hardware dropsrxpackets
Patch to add the ability to detect drops in hardware interfaces via dropwatch.
Adds a tracepoint to net_rx_action to signal everytime a napi instance is
polled.  The dropmon code then periodically checks to see if the rx_frames
counter has changed, and if so, adds a drop notification to the netlink
protocol, using the reserved all-0's vector to indicate the drop location was in
hardware, rather than somewhere in the code.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>

 include/linux/net_dropmon.h |    8 ++
 include/trace/napi.h        |   11 +++
 net/core/dev.c              |    5 +
 net/core/drop_monitor.c     |  124 ++++++++++++++++++++++++++++++++++++++++++--
 net/core/net-traces.c       |    4 +
 net/core/netpoll.c          |    2
 6 files changed, 149 insertions(+), 5 deletions(-)
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-21 16:50:21 -07:00
Mimi Zohar
b9fc745db8 integrity: path_check update
- Add support in ima_path_check() for integrity checking without
incrementing the counts. (Required for nfsd.)
- rename and export opencount_get to ima_counts_get
- replace ima_shm_check calls with ima_counts_get
- export ima_path_check

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-05-22 09:43:41 +10:00