Stub out vm_get_page_prot() if there's no MMU.
This was added by commit 804af2cf6e ("[AGPGART] remove private page
protection map") and is used in commit c07fbfd17e ("fbmem: VM_IO set,
but not propagated") in the fbmem video driver, but the function doesn't
exist on NOMMU, resulting in an undefined symbol at link time.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
pa-risc and ia64 have stacks that grow upwards. Check that
they do not run into other mappings. By making VM_GROWSUP
0x0 on architectures that do not ever use it, we can avoid
some unpleasant #ifdefs in check_stack_guard_page().
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6:
kobject_uevent: fix typo in comments
firmware_class: fix typo in error path
kobject: Break the kobject namespace defs into their own header
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6: (29 commits)
ARM: imx: fix build failure concerning otg/ulpi
USB: ftdi_sio: add product ID for Lenz LI-USB
USB: adutux: fix misuse of return value of copy_to_user()
USB: iowarrior: fix misuse of return value of copy_to_user()
USB: xHCI: update ring dequeue pointer when process missed tds
USB: xhci: Remove buggy assignment in next_trb()
USB: ftdi_sio: Add ID for Ionics PlugComputer
USB: serial: io_ti.c: don't return 0 if writing the download record failed
USB: otg: twl4030: fix wrong assumption of starting state
USB: gadget: Return -ENOMEM on memory allocation failure
USB: gadget: fix composite kernel-doc warnings
USB: ssu100: set tty_flags in ssu100_process_packet
USB: ssu100: add disconnect function for ssu100
USB: serial: export symbol usb_serial_generic_disconnect
USB: ssu100: rework logic for TIOCMIWAIT
USB: ssu100: add register parameter to ssu100_setregister
USB: ssu100: remove duplicate #defines in ssu100
USB: ssu100: refine process_packet in ssu100
USB: ssu100: add locking for port private data in ssu100
USB: r8a66597-udc: return -ENOMEM if kzalloc() fails
...
Warning(include/linux/usb/composite.h:284): No description found for parameter 'disconnect'
Warning(drivers/usb/gadget/composite.c:744): No description found for parameter 'c'
Warning(drivers/usb/gadget/composite.c:744): Excess function parameter 'cdev' description in 'usb_string_ids_n'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (27 commits)
netfilter: fix CONFIG_COMPAT support
isdn/avm: fix build when PCMCIA is not enabled
header: fix broken headers for user space
e1000e: don't check for alternate MAC addr on parts that don't support it
e1000e: disable ASPM L1 on 82573
ll_temac: Fix poll implementation
netxen: fix a race in netxen_nic_get_stats()
qlnic: fix a race in qlcnic_get_stats()
irda: fix a race in irlan_eth_xmit()
net: sh_eth: remove unused variable
netxen: update version 4.0.74
netxen: fix inconsistent lock state
vlan: Match underlying dev carrier on vlan add
ibmveth: Fix opps during MTU change on an active device
ehea: Fix synchronization between HW and SW send queue
bnx2x: Update bnx2x version to 1.52.53-4
bnx2x: Fix PHY locking problem
rds: fix a leak of kernel memory
netlink: fix compat recvmsg
netfilter: fix userspace header warning
...
Break the kobject namespace defs into their own header to avoid a header file
inclusion ordering problem between linux/sysfs.h and linux/kobject.h.
This fixes the build breakage on older versions of gcc.
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
__packed is only defined in kernel space, so we should use
__attribute__((packed)) for the code shared between kernel and user space.
Two __attribute() annotations are replaced with __attribute__() too.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It's a really simple list, and several of the users want to go backwards
in it to find the previous vma. So rather than have to look up the
previous entry with 'find_vma_prev()' or something similar, just make it
doubly linked instead.
Tested-by: Ian Campbell <ijc@hellion.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Recent modprobe and udev versions allow to create device nodes
for modules which are not loaded. Only the first access will cause
the in-kernel module loader to pull-in the module. Systems which
never access the device node will not needlessly load the module,
and no longer need init scripts or other facilities to unconditionally
load it.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Since handle_sysrq() does not take tty as argument anymore we can
drop it from usb_serial_handle_sysrq_char() as well.
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Acked-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Sysrq operations do not accept tty argument anymore so no need to pass
it to us.
[Stephen Rothwell <sfr@canb.auug.org.au>: fix build breakage in drm code
caused by sysrq using bool but not including linux/types.h]
[Sachin Sant <sachinp@in.ibm.com>: fix build breakage in s390 keyboadr
driver]
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Acked-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
"make headers_check" issued the following warning:
CHECK include/linux/netfilter (64 files)
usr/include/linux/netfilter/xt_ipvs.h:19: found __[us]{8,16,32,64} type without #include <linux/types.h>
Fix this by as suggested including linux/types.h.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
fs: brlock vfsmount_lock
fs: scale files_lock
lglock: introduce special lglock and brlock spin locks
tty: fix fu_list abuse
fs: cleanup files_lock locking
fs: remove extra lookup in __lookup_hash
fs: fs_struct rwlock to spinlock
apparmor: use task path helpers
fs: dentry allocation consolidation
fs: fix do_lookup false negative
mbcache: Limit the maximum number of cache entries
hostfs ->follow_link() braino
hostfs: dumb (and usually harmless) tpyo - strncpy instead of strlcpy
remove SWRITE* I/O types
kill BH_Ordered flag
vfs: update ctime when changing the file's permission by setfacl
cramfs: only unlock new inodes
fix reiserfs_evict_inode end_writeback second call
* 'merge-devicetree' of git://git.secretlab.ca/git/linux-2.6:
spi.h: missing kernel-doc notation, please fix
of: fix missing headers for of_address_to_resource() in MTD and SysACE drivers
of: Fix missing includes
ata: update for of_device to platform_device replacement
microblaze: Fix of: eliminate of_device->node and dev_archdata->{of,prom}_node
microblaze: Fix of/address: Merge all of the bus translation code
booting-without-of: Remove nonexistent chapters from TOC, fix numbering
fs: scale files_lock
Improve scalability of files_lock by adding per-cpu, per-sb files lists,
protected with an lglock. The lglock provides fast access to the per-cpu lists
to add and remove files. It also provides a snapshot of all the per-cpu lists
(although this is very slow).
One difficulty with this approach is that a file can be removed from the list
by another CPU. We must track which per-cpu list the file is on with a new
variale in the file struct (packed into a hole on 64-bit archs). Scalability
could suffer if files are frequently removed from different cpu's list.
However loads with frequent removal of files imply short interval between
adding and removing the files, and the scheduler attempts to avoid moving
processes too far away. Also, even in the case of cross-CPU removal, the
hardware has much more opportunity to parallelise cacheline transfers with N
cachelines than with 1.
A worst-case test of 1 CPU allocating files subsequently being freed by N CPUs
degenerates to contending on a single lock, which is no worse than before. When
more than one CPU are allocating files, even if they are always freed by
different CPUs, there will be more parallelism than the single-lock case.
Testing results:
On a 2 socket, 8 core opteron, I measure the number of times the lock is taken
to remove the file, the number of times it is removed by the same CPU that
added it, and the number of times it is removed by the same node that added it.
Booting: locks= 25049 cpu-hits= 23174 (92.5%) node-hits= 23945 (95.6%)
kbuild -j16 locks=2281913 cpu-hits=2208126 (96.8%) node-hits=2252674 (98.7%)
dbench 64 locks=4306582 cpu-hits=4287247 (99.6%) node-hits=4299527 (99.8%)
So a file is removed from the same CPU it was added by over 90% of the time.
It remains within the same node 95% of the time.
Tim Chen ran some numbers for a 64 thread Nehalem system performing a compile.
throughput
2.6.34-rc2 24.5
+patch 24.9
us sys idle IO wait (in %)
2.6.34-rc2 51.25 28.25 17.25 3.25
+patch 53.75 18.5 19 8.75
So significantly less CPU time spent in kernel code, higher idle time and
slightly higher throughput.
Single threaded performance difference was within the noise of microbenchmarks.
That is not to say penalty does not exist, the code is larger and more memory
accesses required so it will be slightly slower.
Cc: linux-kernel@vger.kernel.org
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
lglock: introduce special lglock and brlock spin locks
This patch introduces "local-global" locks (lglocks). These can be used to:
- Provide fast exclusive access to per-CPU data, with exclusive access to
another CPU's data allowed but possibly subject to contention, and to provide
very slow exclusive access to all per-CPU data.
- Or to provide very fast and scalable read serialisation, and to provide
very slow exclusive serialisation of data (not necessarily per-CPU data).
Brlocks are also implemented as a short-hand notation for the latter use
case.
Thanks to Paul for local/global naming convention.
Cc: linux-kernel@vger.kernel.org
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
tty: fix fu_list abuse
tty code abuses fu_list, which causes a bug in remount,ro handling.
If a tty device node is opened on a filesystem, then the last link to the inode
removed, the filesystem will be allowed to be remounted readonly. This is
because fs_may_remount_ro does not find the 0 link tty inode on the file sb
list (because the tty code incorrectly removed it to use for its own purpose).
This can result in a filesystem with errors after it is marked "clean".
Taking idea from Christoph's initial patch, allocate a tty private struct
at file->private_data and put our required list fields in there, linking
file and tty. This makes tty nodes behave the same way as other device nodes
and avoid meddling with the vfs, and avoids this bug.
The error handling is not trivial in the tty code, so for this bugfix, I take
the simple approach of using __GFP_NOFAIL and don't worry about memory errors.
This is not a problem because our allocator doesn't fail small allocs as a rule
anyway. So proper error handling is left as an exercise for tty hackers.
[ Arguably filesystem's device inode would ideally be divorced from the
driver's pseudo inode when it is opened, but in practice it's not clear whether
that will ever be worth implementing. ]
Cc: linux-kernel@vger.kernel.org
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
fs: fs_struct rwlock to spinlock
struct fs_struct.lock is an rwlock with the read-side used to protect root and
pwd members while taking references to them. Taking a reference to a path
typically requires just 2 atomic ops, so the critical section is very small.
Parallel read-side operations would have cacheline contention on the lock, the
dentry, and the vfsmount cachelines, so the rwlock is unlikely to ever give a
real parallelism increase.
Replace it with a spinlock to avoid one or two atomic operations in typical
path lookup fastpath.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
