This patch adds new three helper functions to copy data between an SG
list and a linear buffer.
- sg_copy_from_buffer copies data from linear buffer to an SG list
- sg_copy_to_buffer copies data from an SG list to a linear buffer
When the APIs copy data from a linear buffer to an SG list,
flush_kernel_dcache_page is called. It's not necessary for everyone
but it's a no-op on most architectures and in general the API is not
used in performance critical path.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Add new option MT_ST_SILI to enable setting the SILI bit in reads in variable
block mode. If SILI is set, reading a block shorter than the byte count does
not result in CHECK CONDITION. The length of the block is determined using the
residual count from the HBA. Avoiding the REQUEST SENSE command for every
block speeds up some real applications considerably.
Signed-off-by: Kai Makisara <kai.makisara@kolumbus.fi>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
The effects of cgroup_disable=foo are:
- foo isn't auto-mounted if you mount all cgroups in a single hierarchy
- foo isn't visible as an individually mountable subsystem
As a result there will only ever be one call to foo->create(), at init time;
all processes will stay in this group, and the group will never be mounted on
a visible hierarchy. Any additional effects (e.g. not allocating metadata)
are up to the foo subsystem.
This doesn't handle early_init subsystems (their "disabled" bit isn't set be,
but it could easily be extended to do so if any of the early_init systems
wanted it - I think it would just involve some nastier parameter processing
since it would occur before the command-line argument parser had been run.
Hugh said:
Ballpark figures, I'm trying to get this question out rather than
processing the exact numbers: CONFIG_CGROUP_MEM_RES_CTLR adds 15% overhead
to the affected paths, booting with cgroup_disable=memory cuts that back to
1% overhead (due to slightly bigger struct page).
I'm no expert on distros, they may have no interest whatever in
CONFIG_CGROUP_MEM_RES_CTLR=y; and the rest of us can easily build with or
without it, or apply the cgroup_disable=memory patches.
Unix bench's execl test result on x86_64 was
== just after boot without mounting any cgroup fs.==
mem_cgorup=off : Execl Throughput 43.0 3150.1 732.6
mem_cgroup=on : Execl Throughput 43.0 2932.6 682.0
==
[lizf@cn.fujitsu.com: fix boot option parsing]
Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Sudhir Kumar <skumar@linux.vnet.ibm.com>
Cc: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The commits:
commit 37a47db8d7
Author: Balaji Rao <balajirrao@gmail.com>
Date: Wed Jan 30 13:30:03 2008 +0100
x86: assign IRQs to HPET timers, fix
and
commit e3f37a54f6
Author: Balaji Rao <balajirrao@gmail.com>
Date: Wed Jan 30 13:30:03 2008 +0100
x86: assign IRQs to HPET timers
have been identified to cause a regression on some platforms due to
the assignement of legacy IRQs which makes the legacy devices
connected to those IRQs disfunctional.
Revert them.
This fixes http://bugzilla.kernel.org/show_bug.cgi?id=10382
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
SAT passthrus don't really fit into ATAPI_MISC class. SAT passthru
commands always transfer multiple of 512 bytes and variable length
response is not allowed. This patch creates a separate category -
ATAPI_PASS_THRU - for these.
This fixes HSM violation on "hdparm -I".
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Uninline atapi_cmd_type(). It doesn't really have to be inline and
more case will be added which need to access unexported libata
variable.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Currently include/linux/kvm.h is not considered by make headers_install,
because Kbuild cannot handle " unifdef-$(CONFIG_FOO) += foo.h. This problem
was introduced by
commit fb56dbb31c
Author: Avi Kivity <avi@qumranet.com>
Date: Sun Dec 2 10:50:06 2007 +0200
KVM: Export include/linux/kvm.h only if $ARCH actually supports KVM
Currently, make headers_check barfs due to <asm/kvm.h>, which <linux/kvm.h>
includes, not existing. Rather than add a zillion <asm/kvm.h>s, export kvm.
only if the arch actually supports it.
Signed-off-by: Avi Kivity <avi@qumranet.com>
which makes this an 2.6.25 regression.
One way of solving the issue is to enhance Kbuild, but Avi and David conviced
me, that changing headers_install is not the way to go. This patch changes
the definition for linux/kvm.h to unifdef-y.
If  unifdef-y is used for linux/kvm.h "make headers_check" will fail on all
architectures without asm/kvm.h. Therefore, this patch also provides
asm/kvm.h on all architectures.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Avi Kivity <avi@qumranet.com>
Cc: Sam Ravnborg <sam@ravnborg.org
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (45 commits)
[VLAN]: Proc entry is not renamed when vlan device name changes.
[IPV6]: Fix ICMP relookup error path dst leak
[ATM] drivers/atm/iphase.c: compilation warning fix
IPv6: do not create temporary adresses with too short preferred lifetime
IPv6: only update the lifetime of the relevant temporary address
bluetooth : __rfcomm_dlc_close lock fix
bluetooth : use lockdep sub-classes for diffrent bluetooth protocol
[ROSE/AX25] af_rose: rose_release() fix
mac80211: correct use_short_preamble handling
b43: Fix PCMCIA IRQ routing
b43: Add DMA mapping failure messages
mac80211: trigger ieee80211_sta_work after opening interface
[LLC]: skb allocation size for responses
[IP] UDP: Use SEQ_START_TOKEN.
[NET]: Remove Documentation/networking/sk98lin.txt
[ATM] atm/idt77252.c: Make 2 functions static
[ATM]: Make atm/he.c:read_prom_byte() static
[IPV6] MCAST: Ensure to check multicast listener(s).
[LLC]: Kill llc_station_mac_sa symbol export.
forcedeth: fix locking bug with netconsole
...
SLAB_DESTROY_BY_RCU is not a direct substitute for normal call_rcu()
freeing, since it'll page freeing but NOT object freeing. So change
cfq to do the freeing on its own.
Signed-off-by: Fabio Checconi <fabio@gandalf.sssup.it>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Recent driver core change causes references to parent devices being
dropped early, at device_del() time, as opposed to when all children
are freed. This causes oops in evdev with grabbed devices. Take the
reference to the parent input device ourselves to ensure that it
stays around long enough.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev:
libata: ATA_EHI_LPM should be ATA_EH_LPM
pata_sil680: only enable MMIO on Cell blades
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
[PATCH] mnt_expire is protected by namespace_sem, no need for vfsmount_lock
[PATCH] do shrink_submounts() for all fs types
[PATCH] sanitize locking in mark_mounts_for_expiry() and shrink_submounts()
[PATCH] count ghost references to vfsmounts
[PATCH] reduce stack footprint in namespace.c
Neither of the headers actually compiles when included from userpsace nor
should it be made available as userspace tools should be using the libraries
or at least headers from e2fsprogs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
... and take it out of ->umount_begin() instances. Call with all locks
already taken (by do_umount()) and leave calling release_mounts() to
caller (it will do release_mounts() anyway, so we can just put into
the same list).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
make propagate_mount_busy() exclude references from the vfsmounts
that had been isolated by umount_tree() and are just waiting for
release_mounts() to dispose of their ->mnt_parent/->mnt_mountpoint.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Based upon a lockdep report.
Since ->poll() can be invoked from netpoll with interrupts
disabled, we must not unconditionally enable interrupts
in napi_complete().
Instead we must use local_irq_{save,restore}().
Noticed by Peter Zijlstra:
<irqs disabled>
netpoll_poll()
poll_napi()
spin_trylock(&napi->poll_lock)
poll_one_napi()
napi->poll() := sky2_poll()
napi_complete()
local_irq_disable()
local_irq_enable() <--- *BUG*
<irq>
irq_exit()
do_softirq()
net_rx_action()
spin_lock(&napi->poll_lock) <--- Deadlock!
Because we still hold the lock....
Signed-off-by: David S. Miller <davem@davemloft.net>
