ACPI 4.0 created the logical "processor aggregator device" as
a mechinism for platforms to ask the OS to force otherwise busy
processors to enter (power saving) idle.
The intent is to lower power consumption to ride-out
transient electrical and thermal emergencies,
rather than powering off the server.
On platforms that can save more power/performance via P-states,
the platform will first exhaust P-states before forcing idle.
However, the relative benefit of P-states vs. idle states
is platform dependent, and thus this driver need not know
or care about it.
This driver does not use the kernel's CPU hot-plug mechanism
because after the transient emergency is over, the system must
be returned to its normal state, and hotplug would permanently
break both cpusets and binding.
So to force idle, the driver creates a power saving thread.
The scheduler will migrate the thread to the preferred CPU.
The thread has max priority and has SCHED_RR policy,
so it can occupy one CPU. To save power, the thread will
invoke the deep C-state entry instructions.
To avoid starvation, the thread will sleep 5% of the time
time for every second (current RT scheduler has threshold
to avoid starvation, but if other CPUs are idle,
the CPU can borrow CPU timer from other,
which makes the mechanism not work here)
Vaidyanathan Srinivasan has proposed scheduler enhancements
to allow injecting idle time into the system. This driver doesn't
depend on those enhancements, but could cut over to them
when they are available.
Peter Z. does not favor upstreaming this driver until
the those scheduler enhancements are in place. However,
we favor upstreaming this driver now because it is useful
now, and can be enhanced over time.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
NACKed-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Len Brown <len.brown@intel.com>
* 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
genirq: Fix UP compile failure caused by irq_thread_check_affinity
* 'lockdep-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/peterz/linux-2.6-lockdep:
lockdep: Fix lockdep annotation for pipe_double_lock()
Since genirq: Delegate irq affinity setting to the irq thread
(591d2fb02e) compilation with
CONFIG_SMP=n fails with following error:
/usr/src/linux-2.6/kernel/irq/manage.c:
In function 'irq_thread_check_affinity':
/usr/src/linux-2.6/kernel/irq/manage.c:475:
error: 'struct irq_desc' has no member named 'affinity'
make[4]: *** [kernel/irq/manage.o] Error 1
That commit adds a new function irq_thread_check_affinity() which
uses struct irq_desc.affinity which is only available for CONFIG_SMP=y.
Move that function under #ifdef CONFIG_SMP.
[ tglx@brownpaperbag: compile and boot tested on UP and SMP ]
Signed-off-by: Bruno Premont <bonbons@linux-vserver.org>
LKML-Reference: <20090722222232.2eb3e1c4@neptune.home>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The presumed use of the pipe_double_lock() routine is to lock 2 locks in
a deadlock free way by ordering the locks by their address. However it
fails to keep the specified lock classes in order and explicitly
annotates a deadlock.
Rectify this.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Miklos Szeredi <mszeredi@suse.cz>
LKML-Reference: <1248163763.15751.11098.camel@twins>
* 'perf-counters-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/peterz/linux-2.6-perf: (31 commits)
perf_counter tools: Give perf top inherit option
perf_counter tools: Fix vmlinux symbol generation breakage
perf_counter: Detect debugfs location
perf_counter: Add tracepoint support to perf list, perf stat
perf symbol: C++ demangling
perf: avoid structure size confusion by using a fixed size
perf_counter: Fix throttle/unthrottle event logging
perf_counter: Improve perf stat and perf record option parsing
perf_counter: PERF_SAMPLE_ID and inherited counters
perf_counter: Plug more stack leaks
perf: Fix stack data leak
perf_counter: Remove unused variables
perf_counter: Make call graph option consistent
perf_counter: Add perf record option to log addresses
perf_counter: Log vfork as a fork event
perf_counter: Synthesize VDSO mmap event
perf_counter: Make sure we dont leak kernel memory to userspace
perf_counter tools: Fix index boundary check
perf_counter: Fix the tracepoint channel to perfcounters
perf_counter, x86: Extend perf_counter Pentium M support
...
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
sched: fix nr_uninterruptible accounting of frozen tasks really
sched: fix load average accounting vs. cpu hotplug
sched: Account for vruntime wrapping
* 'tj-block-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc:
virtio_blk: mark virtio_blk with __refdata to kill spurious section mismatch
block: sysfs fix mismatched queue_var_{store,show} in 64bit kernel
ataflop: adjust NULL test
block: fix failfast merge testing in elv_rq_merge_ok()
z2ram: Small cleanup for z2ram.c
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (37 commits)
sky2: Avoid races in sky2_down
drivers/net/mlx4: Adjust constant
drivers/net: Move a dereference below a NULL test
drivers/net: Move a dereference below a NULL test
connector: maintainer/mail update.
USB host CDC Phonet network interface driver
macsonic, jazzsonic: fix oops on module unload
macsonic: move probe function to .devinit.text
can: switch carrier on if device was stopped while in bus-off state
can: restart device even if dev_alloc_skb() fails
can: sja1000: remove duplicated includes
New device ID for sc92031 [1088:2031]
3c589_cs: re-initialize the multicast in the tc589_reset
Fix error return for setsockopt(SO_TIMESTAMPING)
netxen: fix thermal check and shutdown
netxen: fix deadlock on dev close
netxen: fix context deletion sequence
net: Micrel KS8851 SPI network driver
tcp: Use correct peer adr when copying MD5 keys
tcp: Fix MD5 signature checking on IPv4 mapped sockets
...
* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
NFSv4: Fix a problem whereby a buggy server can oops the kernel
NFSv4: Fix an NFSv4 mount regression
NFSv4: Fix an Oops in nfs4_free_lock_state
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
ALSA: ctxfi: Swapped SURROUND-SIDE channels on emu20k2
ALSA: ca0106 - Fix the max capture buffer size
ALSA: hda - Fix pin-setup for Sony VAIO with STAC9872 codecs
ALSA: hda - Add quirk for Gateway T6834c laptop
ALSA: OSS sequencer should be initialized after snd_seq_system_client_init
ALSA: sound/isa: convert nested spin_lock_irqsave to spin_lock
ALSA: hda_codec: Check for invalid zero connections
the "reserved" field was not initialized to zero, resulting in 4 bytes
of stack data leaking to userspace....
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, perf top -p only tracks the pid provided, which isn't very useful
for watching forky loads, so give it an inherit option.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1248165036.9795.10.camel@marge.simson.net>
vmlinux meets the criteria for symbol adjustment, which breaks vmlinux generated symbols.
Fix this by exempting vmlinux. This is a bit fragile in that someone could change the
kernel dso's name, but currently that name is also hardwired.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1248091298.18702.18.camel@marge.simson.net>
If "/sys/kernel/debug" is not a debugfs mount point, search for the debugfs
filesystem in /proc/mounts, but also allows the user to specify
'--debugfs-dir=blah' or set the environment variable: 'PERF_DEBUGFS_DIR'
Signed-off-by: Jason Baron <jbaron@redhat.com>
[ also made it probe "/debug" by default ]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090721181629.GA3094@redhat.com>
Add support to 'perf list' and 'perf stat' for kernel tracepoints. The
implementation creates a 'for_each_subsystem' and 'for_each_event' for
easy iteration over the tracepoints.
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <426129bf9fcc8ee63bb094cf736e7316a7dcd77a.1248190728.git.jbaron@redhat.com>
for some reason, this structure gets compiled as 36 bytes in some files
(the ones that alloacte it) but 40 bytes in others (the ones that use it).
The cause is an off_t type that gets a different size in different
compilation units for some yet-to-be-explained reason.
But the effect is disasterous; the size/offset members of the struct
are at different offsets, and result in mostly complete garbage.
The parser in perf is so robust that this all gets hidden, and after
skipping an certain amount of samples, it recovers.... so this bug
is not normally noticed.
.... except when you want every sample to be exact.
Fix this by just using an explicitly sized type.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <4A655917.9080504@linux.intel.com>
Right now we only print PERF_EVENT_THROTTLE + 1 (ie PERF_EVENT_UNTHROTTLE).
Fix this to print both a throttle and unthrottle event.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090722130546.GE9029@kryten>
perf stat and perf record currently look for all options on the command
line. This can lead to some confusion:
# perf stat ls -l
Error: unknown switch `l'
While we can work around this by adding '--' before the command, the git
option parsing code can stop at the first non option:
# perf stat ls -l
Performance counter stats for 'ls -l':
....
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090722130412.GD9029@kryten>
Anton noted that for inherited counters the counter-id as provided by
PERF_SAMPLE_ID isn't mappable to the id found through PERF_RECORD_ID
because each inherited counter gets its own id.
His suggestion was to always return the parent counter id, since that
is the primary counter id as exposed. However, these inherited
counters have a unique identifier so that events like
PERF_EVENT_PERIOD and PERF_EVENT_THROTTLE can be specific about which
counter gets modified, which is important when trying to normalize the
sample streams.
This patch removes PERF_EVENT_PERIOD in favour of PERF_SAMPLE_PERIOD,
which is more useful anyway, since changing periods became a lot more
common than initially thought -- rendering PERF_EVENT_PERIOD the less
useful solution (also, PERF_SAMPLE_PERIOD reports the more accurate
value, since it reports the value used to trigger the overflow,
whereas PERF_EVENT_PERIOD simply reports the requested period changed,
which might only take effect on the next cycle).
This still leaves us PERF_EVENT_THROTTLE to consider, but since that
_should_ be a rare occurrence, and linking it to a primary id is the
most useful bit to diagnose the problem, we introduce a
PERF_SAMPLE_STREAM_ID, for those few cases where the full
reconstruction is important.
[Does change the ABI a little, but I see no other way out]
Suggested-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1248095846.15751.8781.camel@twins>
the "reserved" field was not initialized to zero, resulting in 4 bytes
of stack data leaking to userspace....
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
There's some odd bug in gcc-4.2 where it miscompiles a simple loop whent
he loop counter is of type 'unsigned char' and it should count to 128.
The compiler will incorrectly decide that a trivial loop like this:
unsigned char i, ...
for (i = 0; i < 128; i++) {
..
is endless, and will compile it to a single instruction that just
branches to itself.
This was triggered by the addition of '-fno-strict-overflow', and we
could play games with compiler versions and go back to '-fwrapv'
instead, but the trivial way to avoid it is to just make the loop
induction variable be an 'int' instead.
Thanks to Krzysztof Oledzki for reporting and testing and to Troy Moure
for digging through assembler differences and finding it.
Reported-and-tested-by: Krzysztof Oledzki <olel@ans.pl>
Found-by: Troy Moure <twmoure@szypr.net>
Gcc-bug-acked-by: Ian Lance Taylor <iant@google.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
commit ca109491f (hrtimer: removing all ur callback modes) moved all
hrtimer callbacks into hard interrupt context when high resolution
timers are active. That breaks code which relied on the assumption
that the callback happens in softirq context.
Provide a generic infrastructure which combines tasklets and hrtimers
together to provide an in-softirq hrtimer experience.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: torvalds@linux-foundation.org
Cc: kaber@trash.net
Cc: David Miller <davem@davemloft.net>
LKML-Reference: <1248265724.27058.1366.camel@twins>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reset rx chain before trying to drain it.
Shut interrupts off last, incase there's something to report.
Signed-off-by: Mike McCormack <mikem@ring3k.org>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Don't leak kernel stack information through uninitialized structure members.
Signed-off-by: Michael Buesch <mb@bu3sch.de>
Acked-by: Borislav Petkov <petkovbb@gmail.com>.
Signed-off-by: David S. Miller <davem@davemloft.net>
I'm using ide on 2.6.30.1 with xfs filesystem. I noticed a kernel memory
leak after writing lots of data, the kmalloc-96 slab cache keeps
growing. It seems the struct ide_cmd kmalloced by idedisk_prepare_flush
is never kfreed.
Commit a09485df9c ("ide: move request
type specific code from ide_end_drive_cmd() to callers (v3)") and
f505d49ffd ("ide: fix barriers support")
cause this regression, cmd->rq must now be set for ide_complete_cmd to
honor the IDE_TFLAG_DYN flag.
Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
Acked-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We just had a case in which a buggy server occasionally returns the wrong
attributes during an OPEN call. While the client does catch this sort of
condition in nfs4_open_done(), and causes the nfs4_atomic_open() to return
-EISDIR, the logic in nfs_atomic_lookup() is broken, since it causes a
fallback to an ordinary lookup instead of just returning the error.
When the buggy server then returns a regular file for the fallback lookup,
the VFS allows the open, and bad things start to happen, since the open
file doesn't have any associated NFSv4 state.
The fix is firstly to return the EISDIR/ENOTDIR errors immediately, and
secondly to ensure that we are always careful when dereferencing the
nfs_open_context state pointer.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Commit 008f55d0e0 (nfs41: recover lease in
_nfs4_lookup_root) forces the state manager to always run on mount. This is
a bug in the case of NFSv4.0, which doesn't require us to send a
setclientid until we want to grab file state.
In any case, this is completely the wrong place to be doing state
management. Moving that code into nfs4_init_session...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The oops http://www.kerneloops.org/raw.php?rawid=537858&msgid= appears to
be due to the nfs4_lock_state->ls_state field being uninitialised. This
happens if the call to nfs4_free_lock_state() is triggered at the end of
nfs4_get_lock_state().
The fix is to move the initialisation of ls_state into the allocator.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The values in the advertising field are typically ADVERTISED_xxx, not
SUPPORTED_xxx. Both SUPPORTED_10000baseT_Full and
ADVERTISED_1000baseT_Full have the same value.
The semantic match that finds this problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@@
struct ethtool_cmd E;
@@
*E.advertising = SUPPORTED_10000baseT_Full
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
If the NULL test is necessary, then the dereference should be moved below
the NULL test.
The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@@
type T;
expression E,E1;
identifier i,fld;
statement S;
@@
- T i = E->fld;
+ T i;
... when != E=E1
when != i
if (E == NULL||...) S
+ i = E->fld;
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
If the NULL test is necessary, then the dereferences should be moved below
the NULL test.
The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@@
type T;
expression E,E1;
identifier i,fld;
statement S;
@@
- T i = E->fld;
+ T i;
... when != E=E1
when != i
BUG_ON (E == NULL||...);
+ i = E->fld;
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Many Nokia handsets support a Phonet interface to the cellular modem
via a vendor-specific USB interface. CDC Phonet follows the
Communications Device Class model, with one control interface, and
and a pair of inactive and active data alternative interface. The later
has two bulk endpoint, one per direction.
This was tested against Nokia E61, Nokia N95, and the existing Phonet
gadget function for the Linux composite USB gadget framework.
Signed-off-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Set the driver data before using it. Fixes an oops when doing rmmod.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
A pointer to mac_sonic_probe is passed to the core via
platform_driver_register and so the function must not disappear when the
.init sections are discarded. Otherwise (if also having HOTPLUG=y)
unbinding and binding a device to the driver via sysfs will result in an
oops as does a device being registered late.
Various other functions that are called by mac_sonic_probe need to move
to .devinit.text, too.
An alternative to this patch is using platform_driver_probe instead of
platform_driver_register plus removing the pointer to the probe function
from the struct platform_driver.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Tested-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
* fix/misc:
ALSA: ca0106 - Fix the max capture buffer size
ALSA: OSS sequencer should be initialized after snd_seq_system_client_init
ALSA: sound/isa: convert nested spin_lock_irqsave to spin_lock
