Give each cpu-context its own timer so that it is a self contained
entity, this eases the way for per-pmu-per-cpu contexts as well as
provides the basic infrastructure to allow different rotation
times per pmu.
Things to look at:
- folding the tick and these TICK_NSEC timers
- separate task context rotation
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: paulus <paulus@samba.org>
Cc: stephane eranian <eranian@googlemail.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Lin Ming <ming.m.lin@intel.com>
Cc: Yanmin <yanmin_zhang@linux.intel.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Neither the overcommit nor the reservation sysfs parameter were
actually working, remove them as they'll only get in the way.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: paulus <paulus@samba.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Replace pmu::{enable,disable,start,stop,unthrottle} with
pmu::{add,del,start,stop}, all of which take a flags argument.
The new interface extends the capability to stop a counter while
keeping it scheduled on the PMU. We replace the throttled state with
the generic stopped state.
This also allows us to efficiently stop/start counters over certain
code paths (like IRQ handlers).
It also allows scheduling a counter without it starting, allowing for
a generic frozen state (useful for rotating stopped counters).
The stopped state is implemented in two different ways, depending on
how the architecture implemented the throttled state:
1) We disable the counter:
a) the pmu has per-counter enable bits, we flip that
b) we program a NOP event, preserving the counter state
2) We store the counter state and ignore all read/overflow events
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: paulus <paulus@samba.org>
Cc: stephane eranian <eranian@googlemail.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Lin Ming <ming.m.lin@intel.com>
Cc: Yanmin <yanmin_zhang@linux.intel.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
Cc: David Miller <davem@davemloft.net>
Cc: Michael Cree <mcree@orcon.net.nz>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Use hw_perf_event::period_left instead of hw_perf_event::remaining
and win back 8 bytes.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: paulus <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
On top of the SMT and MC scheduling domains this adds the BOOK scheduling
domain. This is useful for NUMA like machines which do not have an interface
which tells which piece of memory is attached to which node or where the
hardware performs striping.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20100831082844.253053798@de.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
lg_lock_global() currently only acquires spinlocks for online CPUs, but
it's meant to lock all possible CPUs. Lglock-protected resources may be
associated with removed CPUs - and, indeed, that could happen with the
per-superblock open files lists.
At Nick's suggestion, change for_each_online_cpu() to
for_each_possible_cpu() to protect accesses to those resources.
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Acked-by: Nick Piggin <npiggin@kernel.dk>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alex Shi found a regression when doing ffsb test. The test has several threads,
and each thread creates a small file, write to it and then delete it. ffsb
reports about 20% regression and Alex bisected it to 43d2932d88. The test
will call __mark_inode_dirty 3 times. without this commit, we only take
inode_lock one time, while with it, we take the lock 3 times with flags (
I_DIRTY_SYNC,I_DIRTY_PAGES,I_DIRTY). Perf shows the lock contention increased
too much. Below proposed patch fixes it.
fs is allocating blocks, which usually means file writes and the inode
will be dirtied soon. We fully dirty the inode to reduce some inode_lock
contention in several calls of __mark_inode_dirty.
Jan Kara: Added comment.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Alex Shi <alex.shi@intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Also, a number of changes were made based on the assumption that
rds.h wasn't exported, so roll these back.
Signed-off-by: Andy Grover <andy.grover@oracle.com>
Add two CMSGs for masked versions of cswp and fadd. args
struct modified to use a union for different atomic op type's
arguments. Change IB to do masked atomic ops. Atomic op type
in rds_message similarly unionized.
Signed-off-by: Andy Grover <andy.grover@oracle.com>
Add a flag to the API so users can indicate they want
silent operations. This is needed because silent ops
cannot be used with USE_ONCE MRs, so we can't just
assume silent.
Also, change send_xmit to do atomic op before rdma op if
both are present, and centralize the hairy logic to determine if
we want to attempt silent, or not.
Signed-off-by: Andy Grover <andy.grover@oracle.com>
Implement a CMSG-based interface to do FADD and CSWP ops.
Alter send routines to handle atomic ops.
Add atomic counters to stats.
Add xmit_atomic() to struct rds_transport
Inline rds_ib_send_unmap_rdma into unmap_rm
Signed-off-by: Andy Grover <andy.grover@oracle.com>
We use rcu_dereference_check(p, rcu_read_lock_held() ||
lockdep_rtnl_is_held()) several times in network stack.
More usages to come too, so its time to create a helper.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, mcheck: Avoid duplicate sysfs links/files for thresholding banks
io-mapping: Fix the address space annotations
x86: Fix the address space annotations of iomap_atomic_prot_pfn()
x86, mm: Fix CONFIG_VMSPLIT_1G and 2G_OPT trampoline
x86, hwmon: Fix unsafe smp_processor_id() in thermal_throttle_add_dev
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
gcc-4.6: kernel/*: Fix unused but set warnings
mutex: Fix annotations to include it in kernel-locking docbook
pid: make setpgid() system call use RCU read-side critical section
MAINTAINERS: Add RCU's public git tree
commit 052dc7c45i "spi/dw_spi: conditional transfer mode change"
introduced cs_control code, which has a bug by using bit offset
for spi mode to set transfer mode in control register. Also it
forces devices who don't need cs_control to re-configure the
control registers for each spi transfer. This patch will fix them
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
The full cleanup of init_MUTEX[_LOCKED] and DECLARE_MUTEX has not been
done. Some of the users are real semaphores and we should name them as
such instead of confusing everyone with "MUTEX".
Provide the infrastructure to get finally rid of init_MUTEX[_LOCKED]
and DECLARE_MUTEX.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Christoph Hellwig <hch@infradead.org>
LKML-Reference: <20100907125054.795929962@linutronix.de>
On UP, percpu allocations were redirected to kmalloc. This has the
following problems.
* For certain amount of allocations (determined by
PERCPU_DYNAMIC_EARLY_SLOTS and PERCPU_DYNAMIC_EARLY_SIZE), percpu
allocator can be used before the usual kernel memory allocator is
brought online. On SMP, this is used to initialize the kernel
memory allocator.
* percpu allocator honors alignment upto PAGE_SIZE but kmalloc()
doesn't. For example, workqueue makes use of larger alignments for
cpu_workqueues.
Currently, users of percpu allocators need to handle UP differently,
which is somewhat fragile and ugly. Other than small amount of
memory, there isn't much to lose by enabling percpu allocator on UP.
It can simply use kernel memory based chunk allocation which was added
for SMP archs w/o MMUs.
This patch removes mm/percpu_up.c, builds mm/percpu.c on UP too and
makes UP build use percpu-km. As percpu addresses and kernel
addresses are always identity mapped and static percpu variables don't
need any special treatment, nothing is arch dependent and mm/percpu.c
implements generic setup_per_cpu_areas() for UP.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
In preparation of enabling percpu allocator for UP, reduce
PCPU_MIN_UNIT_SIZE to 32k. On UP, the first chunk doesn't have to
include static percpu variables and chunk size can be smaller which is
important as UP percpu allocator will use contiguous kernel memory to
populate chunks.
PCPU_MIN_UNIT_SIZE also determines the maximum supported allocation
size but 32k should still be enough.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Christoph Lameter <cl@linux.com>
These functions are used only by percpu memory allocator on SMP.
Don't build them on UP.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Nick Piggin <npiggin@kernel.dk>
Reviewed-by: Chrsitoph Lameter <cl@linux.com>
The current practice of waiting for cache updates by queueing the
whole request to be retried has (at least) two problems.
1/ With NFSv4, requests can be quite complex and re-trying a whole
request when a later part fails should only be a last-resort, not a
normal practice.
2/ Large requests, and in particular any 'write' request, will not be
queued by the current code and doing so would be undesirable.
In many cases only a very sort wait is needed before the cache gets
valid data.
So, providing the underlying transport permits it by setting
->thread_wait,
arrange to wait briefly for an upcall to be completed (as reflected in
the clearing of CACHE_PENDING).
If the short wait was not long enough and CACHE_PENDING is still set,
fall back on the old approach.
The 'thread_wait' value is set to 5 seconds when there are spare
threads, and 1 second when there are no spare threads.
These values are probably much higher than needed, but will ensure
some forward progress.
Note that as we only request an update for a non-valid item, and as
non-valid items are updated in place it is extremely unlikely that
cache_check will return -ETIMEDOUT. Normally cache_defer_req will
sleep for a short while and then find that the item is_valid.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This protects us from confusion when the wallclock time changes.
We convert to and from wallclock when setting or reading expiry
times.
Also use seconds since boot for last_clost time.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Rather can duplicating this idiom twice, put it in an inline function.
This reduces the usage of 'expiry_time' out side the sunrpc/cache.c
code and thus the impact of a change that is about to be made to that
field.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
PCI: bus speed strings should be const
PCI hotplug: Fix build with CONFIG_ACPI unset
PCI: PCIe: Remove the port driver module exit routine
PCI: PCIe: Move PCIe PME code to the pcie directory
PCI: PCIe: Disable PCIe port services during port initialization
PCI: PCIe: Ask BIOS for control of all native services at once
ACPI/PCI: Negotiate _OSC control bits before requesting them
ACPI/PCI: Do not preserve _OSC control bits returned by a query
ACPI/PCI: Make acpi_pci_query_osc() return control bits
ACPI/PCI: Reorder checks in acpi_pci_osc_control_set()
PCI: PCIe: Introduce commad line switch for disabling port services
PCI: PCIe AER: Introduce pci_aer_available()
x86/PCI: only define pci_domain_nr if PCI and PCI_DOMAINS are set
PCI: provide stub pci_domain_nr function for !CONFIG_PCI configs
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
percpu: fix a mismatch between code and comment
percpu: fix a memory leak in pcpu_extend_area_map()
percpu: add __percpu notations to UP allocator
percpu: handle __percpu notations in UP accessors
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6:
tty: fix tty_line must not be equal to number of allocated tty pointers in tty driver
serial: bfin_sport_uart: restore transmit frame sync fix
serial: fix port type conflict between NS16550A & U6_16550A
MAINTAINERS: orphan isicom
vt: Fix console corruption on driver hand-over.
There is only one place in the dlm where the sb_status is set
and that is queue_cast(). Tracing back the callers of that
function shows that the listed set of return values is
out of date, so here are an updated set.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
Sandybridge GTT has new cache control bits in PTE, which controls
graphics page cache in LLC or LLC/MLC, so we need to extend the mask
function to respect the new bits.
And set cache control to always LLC only by default on Gen6.
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: stable@kernel.org
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
The irq stacks, located in the percpu-area, need to be
THREAD_SIZE aligned. Add the infrastucture to align percpu
variables to larger-than-pagesize amounts within the percpu
area, and use it to specify the alignment for the irq stacks.
Also align the percpu area itself to THREAD_SIZE.
This should make irq stacks work with 8K THREAD_SIZE.
Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Cc: Tejun Heo <tj@kernel.org>
Cc: hch@lst.de
LKML-Reference: <1283799222.15941.1393621887@webmail.messagingengine.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
cgroup_attach_task_current_cg API that have upstream is backwards: we
really need an API to attach to the cgroups from another process A to
the current one.
In our case (vhost), a priveledged user wants to attach it's task to cgroups
from a less priveledged one, the API makes us run it in the other
task's context, and this fails.
So let's make the API generic and just pass in 'from' and 'to' tasks.
Add an inline wrapper for cgroup_attach_task_current_cg to avoid
breaking bisect.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Fix kernel-doc notation in linux/mutex.h and kernel/mutex.c,
then add these 2 files to the kernel-locking docbook as the
Mutex API reference chapter.
Add one API function to mutex-design.txt and correct a typo in
that file.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
LKML-Reference: <20100902154816.6cc2f9ad.randy.dunlap@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
fresh skbs have ip_summed set to CHECKSUM_NONE (0)
We can avoid setting again skb->ip_summed to CHECKSUM_NONE in drivers.
Introduce skb_checksum_none_assert() helper so that we keep this
assertion documented in driver sources.
Change most occurrences of :
skb->ip_summed = CHECKSUM_NONE;
by :
skb_checksum_none_assert(skb);
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
