There is a problem that kdump(2nd kernel) sometimes hangs up due
to a pending IPI from 1st kernel. Kernel panic occurs because IPI
comes before call_single_queue is initialized.
To fix the crash, rename init_call_single_data() to call_function_init()
and call it in start_kernel() so that call_single_queue can be
initialized before enabling interrupts.
The details of the crash are:
(1) 2nd kernel boots up
(2) A pending IPI from 1st kernel comes when irqs are first enabled
in start_kernel().
(3) Kernel tries to handle the interrupt, but call_single_queue
is not initialized yet at this point. As a result, in the
generic_smp_call_function_single_interrupt(), NULL pointer
dereference occurs when list_replace_init() tries to access
&q->list.next.
Therefore this patch changes the name of init_call_single_data()
to call_function_init() and calls it before local_irq_enable()
in start_kernel().
Signed-off-by: Takao Indoh <indou.takao@jp.fujitsu.com>
Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Milton Miller <miltonm@bga.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: kexec@lists.infradead.org
Link: http://lkml.kernel.org/r/D6CBEE2F420741indou.takao@jp.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This workaround aims to break the deadlock situation
which raises during continuous transfer of data for long
duration over uart with hardware flow control. It is
observed that CTS interrupt cannot be cleared in uart
interrupt register (ICR). Hence further transfer over
uart gets blocked.
It is seen that during such deadlock condition ICR
don't get cleared even on multiple write. This leads
pass_counter to decrease and finally reach zero. This
can be taken as trigger point to run this UART_BT_WA.
Workaround backups the register configuration, does soft
reset of UART using BIT-0 of PRCC_K_SOFTRST_SET/CLEAR
registers and restores the registers.
This patch also provides support for uart init and exit
function calls if present.
Signed-off-by: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The clocksource watchdog code is interruptible and it has been
observed that this can trigger false positives which disable the TSC.
The reason is that an interrupt storm or a long running interrupt
handler between the read of the watchdog source and the read of the
TSC brings the two far enough apart that the delta is larger than the
unstable treshold. Move both reads into a short interrupt disabled
region to avoid that.
Reported-and-tested-by: Vernon Mauery <vernux@us.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@kernel.org
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
AFS: Use i_generation not i_version for the vnode uniquifier
AFS: Set s_id in the superblock to the volume name
vfs: Fix data corruption after failed write in __block_write_begin()
afs: afs_fill_page reads too much, or wrong data
VFS: Fix vfsmount overput on simultaneous automount
fix wrong iput on d_inode introduced by e6bc45d65d
Delay struct net freeing while there's a sysfs instance refering to it
afs: fix sget() races, close leak on umount
ubifs: fix sget races
ubifs: split allocation of ubifs_info into a separate function
fix leak in proc_set_super()
Make GPIOF_ defined values available even when GPIOLIB nor GENERIC_GPIO
is enabled by moving them to <linux/gpio.h>.
Fixes these build errors in linux-next:
sound/soc/codecs/ak4641.c:524: error: 'GPIOF_OUT_INIT_LOW' undeclared (first use in this function)
sound/soc/codecs/wm8915.c:2921: error: 'GPIOF_OUT_INIT_LOW' undeclared (first use in this function)
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
The "hostname" tool falls back to setting the hostname to "localhost" if
/etc/hostname does not exist. Distribution init scripts have the same
fallback. However, if userspace never calls sethostname, such as when
booting with init=/bin/sh, or otherwise booting a minimal system without
the usual init scripts, the default hostname of "(none)" remains,
unhelpfully appearing in various places such as prompts ("root@(none):~#")
and logs. Furthermore, "(none)" doesn't typically resolve to anything
useful.
Make the default hostname configurable. This removes the need for the
standard fallback, provides a useful default for systems that never call
sethostname, and makes minimal systems that much more useful with less
configuration. Distributions could choose to use "localhost" here to
avoid the fallback, while embedded systems may wish to use a specific
target hostname.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: David Miller <davem@davemloft.net>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Kel Modderman <kel@otaku42.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Recently, Robert Mueller reported (http://lkml.org/lkml/2010/9/12/236)
that zone_reclaim_mode doesn't work properly on his new NUMA server (Dual
Xeon E5520 + Intel S5520UR MB). He is using Cyrus IMAPd and it's built on
a very traditional single-process model.
* a master process which reads config files and manages the other
process
* multiple imapd processes, one per connection
* multiple pop3d processes, one per connection
* multiple lmtpd processes, one per connection
* periodical "cleanup" processes.
There are thousands of independent processes. The problem is, recent
Intel motherboard turn on zone_reclaim_mode by default and traditional
prefork model software don't work well on it. Unfortunatelly, such models
are still typical even in the 21st century. We can't ignore them.
This patch raises the zone_reclaim_mode threshold to 30. 30 doesn't have
any specific meaning. but 20 means that one-hop QPI/Hypertransport and
such relatively cheap 2-4 socket machine are often used for traditional
servers as above. The intention is that these machines don't use
zone_reclaim_mode.
Note: ia64 and Power have arch specific RECLAIM_DISTANCE definitions.
This patch doesn't change such high-end NUMA machine behavior.
Dave Hansen said:
: I know specifically of pieces of x86 hardware that set the information
: in the BIOS to '21' *specifically* so they'll get the zone_reclaim_mode
: behavior which that implies.
:
: They've done performance testing and run very large and scary benchmarks
: to make sure that they _want_ this turned on. What this means for them
: is that they'll probably be de-optimized, at least on newer versions of
: the kernel.
:
: If you want to do this for particular systems, maybe _that_'s what we
: should do. Have a list of specific configurations that need the
: defaults overridden either because they're buggy, or they have an
: unusual hardware configuration not really reflected in the distance
: table.
And later said:
: The original change in the hardware tables was for the benefit of a
: benchmark. Said benchmark isn't going to get run on mainline until the
: next batch of enterprise distros drops, at which point the hardware where
: this was done will be irrelevant for the benchmark. I'm sure any new
: hardware will just set this distance to another yet arbitrary value to
: make the kernel do what it wants. :)
:
: Also, when the hardware got _set_ to this initially, I complained. So, I
: guess I'm getting my way now, with this patch. I'm cool with it.
Reported-by: Robert Mueller <robm@fastmail.fm>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Christoph Lameter <cl@linux.com>
Acked-by: David Rientjes <rientjes@google.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Acked-by: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix <linux/kmsg_dump.h> when CONFIG_PRINTK is not enabled:
include/linux/kmsg_dump.h:56: error: 'EINVAL' undeclared (first use in this function)
include/linux/kmsg_dump.h:61: error: 'EINVAL' undeclared (first use in this function)
Looks like commit 595dd3d8bf ("kmsg_dump: fix build for
CONFIG_PRINTK=n") uses EINVAL without having the needed header file(s),
but I'm sure that I build tested that patch also. oh well.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, memcg reclaim can disable swap token even if the swap token mm
doesn't belong in its memory cgroup. It's slightly risky. If an admin
creates very small mem-cgroup and silly guy runs contentious heavy memory
pressure workload, every tasks are going to lose swap token and then
system may become unresponsive. That's bad.
This patch adds 'memcg' parameter into disable_swap_token(). and if the
parameter doesn't match swap token, VM doesn't disable it.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Rik van Riel<riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the NLM daemon is killed on the NFS server, we can currently end up
hanging forever on an 'unlock' request, instead of aborting. Basically,
if the rpcbind request fails, or the server keeps returning garbage, we
really want to quit instead of retrying.
Tested-by: Vasily Averin <vvs@sw.ru>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
Commit a26ac2455ffcf3(rcu: move TREE_RCU from softirq to kthread)
introduced performance regression. In an AIM7 test, this commit degraded
performance by about 40%.
The commit runs rcu callbacks in a kthread instead of softirq. We observed
high rate of context switch which is caused by this. Out test system has
64 CPUs and HZ is 1000, so we saw more than 64k context switch per second
which is caused by RCU's per-CPU kthread. A trace showed that most of
the time the RCU per-CPU kthread doesn't actually handle any callbacks,
but instead just does a very small amount of work handling grace periods.
This means that RCU's per-CPU kthreads are making the scheduler do quite
a bit of work in order to allow a very small amount of RCU-related
processing to be done.
Alex Shi's analysis determined that this slowdown is due to lock
contention within the scheduler. Unfortunately, as Peter Zijlstra points
out, the scheduler's real-time semantics require global action, which
means that this contention is inherent in real-time scheduling. (Yes,
perhaps someone will come up with a workaround -- otherwise, -rt is not
going to do well on large SMP systems -- but this patch will work around
this issue in the meantime. And "the meantime" might well be forever.)
This patch therefore re-introduces softirq processing to RCU, but only
for core RCU work. RCU callbacks are still executed in kthread context,
so that only a small amount of RCU work runs in softirq context in the
common case. This should minimize ksoftirqd execution, allowing us to
skip boosting of ksoftirqd for CONFIG_RCU_BOOST=y kernels.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Tested-by: "Alex,Shi" <alex.shi@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
PPP handles packet loss but does not work with out of order packets.
This change performs reordering of incoming data packets within a
sliding window of one second. Since sequence number is optional,
receiving a packet without it will drop all queued packets.
Currently the logic is triggered by incoming packets, so queued
packets have to wait till another packet is arrived. It is done for
simplicity since no additional locks or threads are required. For
reliable protocols, a retransmission will kick it. For unreliable
protocols, queued packets just seem like packet loss. Time-critical
protocols might be broken, but they never work with queueing anyway.
Signed-off-by: Chia-chi Yeh <chiachi@android.com>
Based on the list of enabled USB functions, we can now switch the vendor ID
as well as the product ID.
Signed-off-by: Mike Lockwood <lockwood@android.com>
This reverts commit f0b0e4bec1e89014f3dcef4da8bcf95428cc771c.
The reverted commit incorrectly calculates the size of eMMC
devices in some (all?) cases.
This revert may cause problems in cases where the bootloader was
bug-compatible and puts a GPT partition at the incorrect end of
the eMMC device.
Signed-off-by: Colin Cross <ccross@android.com>
synchronize_rcu can be very expensive, averaging 100 ms in
some cases. In cgroup_attach_task, it is used to prevent
a task->cgroups pointer dereferenced in an RCU read side
critical section from being invalidated, by delaying the
call to put_css_set until after an RCU grace period.
To avoid the call to synchronize_rcu, make the put_css_set
call rcu-safe by moving the deletion of the css_set links
into free_css_set_work, scheduled by the rcu callback
free_css_set_rcu.
The decrement of the cgroup refcount is no longer
synchronous with the call to put_css_set, which can result
in the cgroup refcount staying positive after the last call
to cgroup_attach_task returns. To allow the cgroup to be
deleted with cgroup_rmdir synchronously after
cgroup_attach_task, have rmdir check the refcount of all
associated css_sets. If cgroup_rmdir is called on a cgroup
for which the css_sets all have refcount zero but the
cgroup refcount is nonzero, reuse the rmdir waitqueue to
block the rmdir until free_css_set_work is called.
Signed-off-by: Colin Cross <ccross@android.com>
Changes the meaning of CGRP_RELEASABLE to be set on any cgroup
that has ever had a task or cgroup in it, or had css_get called
on it. The bit is set in cgroup_attach_task, cgroup_create,
and __css_get. It is not necessary to set the bit in
cgroup_fork, as the task is either in the root cgroup, in
which can never be released, or the task it was forked from
already set the bit in croup_attach_task.
Signed-off-by: Colin Cross <ccross@android.com>
This governor is designed for latency-sensitive workloads, such as
interactive user interfaces. The interactive governor aims to be
significantly more responsive to ramp CPU quickly up when CPU-intensive
activity begins.
Existing governors sample CPU load at a particular rate, typically
every X ms. This can lead to under-powering UI threads for the period of
time during which the user begins interacting with a previously-idle system
until the next sample period happens.
The 'interactive' governor uses a different approach. Instead of sampling
the CPU at a specified rate, the governor will check whether to scale the
CPU frequency up soon after coming out of idle. When the CPU comes out of
idle, a timer is configured to fire within 1-2 ticks. If the CPU is very
busy from exiting idle to when the timer fires then we assume the CPU is
underpowered and ramp to MAX speed.
If the CPU was not sufficiently busy to immediately ramp to MAX speed, then
the governor evaluates the CPU load since the last speed adjustment,
choosing the highest value between that longer-term load or the short-term
load since idle exit to determine the CPU speed to ramp to.
A realtime thread is used for scaling up, giving the remaining tasks the
CPU performance benefit, unlike existing governors which are more likely to
schedule rampup work to occur after your performance starved tasks have
completed.
The tuneables for this governor are:
/sys/devices/system/cpu/cpufreq/interactive/min_sample_time:
The minimum amount of time to spend at the current frequency before
ramping down. This is to ensure that the governor has seen enough
historic CPU load data to determine the appropriate workload.
Default is 80000 uS.
/sys/devices/system/cpu/cpufreq/interactive/go_maxspeed_load
The CPU load at which to ramp to max speed. Default is 85.
Change-Id: Ib2b362607c62f7c56d35f44a9ef3280f98c17585
Signed-off-by: Mike Chan <mike@android.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Bug: 3152864
the csd sector count reported by eMMC 4.3+ cards includes the boot
partition size; subtract this from the size reported to the disk
since the boot partition is inaccessible
Change-Id: I601b83aa0159b7aa446409ea8c945b256dd0b5b1
Signed-off-by: Gary King <gking@nvidia.com>
Platform must register cpu power function that return power in
milliWatt seconds.
Change-Id: I1caa0335e316c352eee3b1ddf326fcd4942bcbe8
Signed-off-by: Mike Chan <mike@android.com>
Introduce new platform callback hooks for cpuacct for tracking CPU frequencies
Not all platforms / architectures have a set CPU_FREQ_TABLE defined
for CPU transition speeds. In order to track time spent in at various
CPU frequencies, we enable platform callbacks from cpuacct for this accounting.
Architectures that support overclock boosting, or don't have pre-defined
frequency tables can implement their own bucketing system that makes sense
given their cpufreq scaling abilities.
New file:
cpuacct.cpufreq reports the CPU time (in nanoseconds) spent at each CPU
frequency.
Change-Id: I10a80b3162e6fff3a8a2f74dd6bb37e88b12ba96
Signed-off-by: Mike Chan <mike@android.com>
Originally written by HTC. Contributions by Motorola and AKM.
misc: Import akm8975 from Motorola
Major style and code cleanups by Praveen Bharathi <pbharathi@motorola.com>
misc: akm8975: clean up code violations in akm8975.c
misc: akm8975: Clean up coding style, add suspend and resume
Change-Id: I4196913f15aec2dfbed47506d3dc085aada8e92d
Signed-off-by: Dima Zavin <dima@android.com>
This patch adds a notifier which can be used by subsystems that may
be interested in when a task has completely died and is about to
have it's last resource freed.
The Android lowmemory killer uses this to determine when a task
it has killed has finally given up its goods.
Signed-off-by: San Mehat <san@google.com>
This provides kernel_debugger() which can be called from an interrupt
context low level debugger wedge to execute commands that inspect
kernel state. It doesn't do much on its own.
Signed-off-by: Brian Swetland <swetland@google.com>
kernel_debugger_core: Add sysrq command.
sysrq <c> will run the sysrq command <c> and dump what
was added to the kernel log while the command ran.
Signed-off-by: Brian Swetland <swetland@google.com>
Signed-off-by: Arve Hjønnevåg <arve@android.com>
net: Fix a bitmask in PPPoPNS and rename constants in PPPoPNS and PPPoLAC.
Signed-off-by: Chia-chi Yeh <chiachi@android.com>
net: Fix a potential deadlock while releasing PPPoLAC/PPPoPNS socket.
PPP driver guarantees that no thread will be executing start_xmit() after
returning from ppp_unregister_channel(). To achieve this, a spinlock (downl)
is used. In pppolac_release(), ppp_unregister_channel() is called after sk_udp
is locked. At the same time, another thread might be running in pppolac_xmit()
with downl. Thus a deadlock will occur if the thread tries to lock sk_udp.
The same situation might happen on sk_raw in pppopns_release().
Signed-off-by: Chia-chi Yeh <chiachi@android.com>
net: Force PPPoLAC and PPPoPNS to bind an interface before creating PPP channel.
It is common to manipulate the routing table after configuring PPP device.
Since both PPPoLAC and PPPoPNS run over IP, care must be taken to make sure
that there is no loop in the routing table.
Although this can be done by adding a host route, it might still cause
problems when the interface is down for some reason.
To solve this, this patch forces both drivers to bind an interface before
creating PPP channel, so the system will not re-route the tunneling sockets
to another interface when the original one is down. Another benefit is that
now the host route is no longer required, so there is no need to remove it
when PPP channel is closed.
Signed-off-by: Chia-chi Yeh <chiachi@android.com>
net: Avoid sleep-inside-spinlock in PPPoLAC and PPPoPNS.
Since recv() and xmit() are called with a spinlock held, routines which might
sleep cannot be used. This issue is solved by following changes:
Incoming packets are now processed in backlog handler, recv_core(), instead of
recv(). Since backlog handler is always executed with socket spinlock held, the
requirement of ppp_input() is still satisfied.
Outgoing packets are now processed in workqueue handler, xmit_core(), instead of
xmit(). Note that kernel_sendmsg() is no longer used to prevent touching dead
sockets.
In release(), lock_sock() and pppox_unbind_sock() ensure that no thread is in
recv_core() or xmit(). Then socket handlers are restored before release_sock(),
so no packets will leak in backlog queue.
Signed-off-by: Chia-chi Yeh <chiachi@android.com>
net: Fix msg_iovlen in PPPoLAC and PPPoPNS.
Although any positive value should work (which is always true in both drivers),
the correct value should be 1.
Signed-off-by: Chia-chi Yeh <chiachi@android.com>
- Added multiple ACM instance support in Android gadget
- Fixed multiple instance naming issue in ACM function
- Increased max instances from 4 to 8
Change-Id: I65f1b0be94da859bab7ec0ad7cd804b896c7c4c5
Signed-off-by: John Michelau <john.michelau@motorola.com>
For backward compatibility with PTP, MTP is limited to a 32-bit file size.
When transferring files greater than 4 gig, MTP uses 0xFFFFFFFF as the file size
and the receiver reads until it receives a short packet.
Expanded size of mtp_file_range.length to 64 bits and added support for
writing zero length packets.
Signed-off-by: Mike Lockwood <lockwood@android.com>
Use this rather than calling usb_gadget_disconnect and usb_gadget_connect
directly to avoid sending USB disconnect events to userspace when resetting
the bus.
Signed-off-by: Mike Lockwood <lockwood@android.com>
Add switch to notify current USB configuration. This can be used to detect
USB connect and disconnect events.
Broadcast a change via the usb_composite class when a USB function is
enabled or disabled.
Rename usb_function.hidden to usb_function.disabled.
Signed-off-by: Mike Lockwood <lockwood@android.com>
