In many cases, especially in networking, it can be beneficial to know at
compile time whether the architecture can do unaligned accesses efficiently.
This patch introduces a new Kconfig symbol
HAVE_EFFICIENT_UNALIGNED_ACCESS
for that purpose and adds it to the powerpc and x86 architectures. Also add
some documentation about alignment and networking, and especially one intended
use of this symbol.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Ingo Molnar <mingo@elte.hu> [x86 architecture part]
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove the conditional surrounding the definition of list_add() from list.h
since, if you define CONFIG_DEBUG_LIST, the definition you will subsequently
pick up from lib/list_debug.c will be absolutely identical, at which point you
can remove that redundant definition from list_debug.c as well.
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Cc: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Extend memparse() to allow the caller to use a NULL second parameter, which
would represent no interest in returning the address of the end of the parsed
string.
In numerous cases, callers invoke memparse() to parse a possibly-suffixed
string (such as "64K" or "2G" or whatever) and define a character pointer to
accept the end pointer being returned by memparse() even though they have no
interest in it and promptly throw it away.
This (backward-compatible) enhancement allows callers to use NULL in the cases
where they just don't care about getting back that end pointer.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There seems to be little point in explicitly setting, then testing the macro
BUILD_CRAMDISK within the context of a single source file.
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This header file has been unused for quite some time, and the
corresponding source files appear to have been removed back in commit
99eb8a550d ("Remove the arm26 port")
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Cc: Adrian Bunk <bunk@stusta.de>
Cc: Ian Molton <spyro@f2s.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Every file should include the headers containing the externs for its
global code (in this case for rd_doload).
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
uname -m was leaving a newline in $arch, and not passing the tests.
Also, printing the unknown arch on failure is probably helpful.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, checkstack.pl only looks for fixed subtractions from the stack
pointer. However, things like this:
void function(int size)
{
char stackbuster[size << 2];
...
are certainly worth pointing out, I think.
This could perhaps be done more cleanly, and the following patch only
adds "dynamic" REs for x86 and x86_64, but it works:
0x00b0 crypto_cbc_decrypt_inplace [cbc]: Dynamic (%rax)
0x00ad crypto_pcbc_decrypt_inplace [pcbc]: Dynamic (%rax)
0x02f6 crypto_pcbc_encrypt_inplace [pcbc]: Dynamic (%rax)
0x036c _crypto_xcbc_digest_setkey [xcbc]: Dynamic (%rax)
...
(Inspired by Keith Owens' old stack-check script)
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace the private BE16/BE32/BE64 macros with direct calls to
get_unaligned_be16/32/64.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There haave been several areas in the kernel where an int has been used for
flags in local_irq_save() and friends instead of a long. This can cause some
hard to debug problems on some architectures.
This patch adds a typecheck inside the irqsave and restore functions to flag
these cases.
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: build fix]
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Needed to fix up a recursive include snafu in
locking-add-typecheck-on-irqsave-and-friends-for-correct-flags.patch
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For it doesn't exist on i386.
Cc: Ian Molton <spyro@f2s.com>
Cc: Dmitry Baryshkov <dbaryshkov@gmail.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Changeset 7fa897b91a ("ide: trivial sparse
annotations") created an IDE bootup regression on big-endian systems.
In drivers/ide/ide-iops.c, function ide_fixstring() we now have the
loop:
for (p = end ; p != s;)
be16_to_cpus((u16 *)(p -= 2));
which will never terminate on big-endian because in such
a configuration be16_to_cpus() evaluates to "do { } while (0)"
Therefore, always evaluate the arguments to nop endian transformation
operations.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Both commits 0f17e4c796 ("Add missing
semaphore.h includes") and 4933d07531
("m68k: drivers/input/serio/hp_sdc.c needs <linux/semaphore.h>") added a
We only really need one ;)
Reported-by: Huang Weiyi <weiyi.huang@gmail.com>
Requested-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
virtio: Add transport feature handling stub for virtio_ring.
virtio: Rename set_features to finalize_features
virtio: Formally reserve bits 28-31 to be 'transport' features.
s390: use virtio_console for KVM on s390
virtio: console as a config option
virtio_console: use virtqueue notification for hvc_console
hvc_console: rework setup to replace irq functions with callbacks
virtio_blk: check for hardsector size from host
virtio: Use bus_type probe and remove methods
virtio: don't always force a notification when ring is full
virtio: clarify that ABI is usable by any implementations
virtio: Recycle unused recv buffer pages for large skbs in net driver
virtio net: Allow receiving SG packets
virtio net: Add ethtool ops for SG/GSO
virtio: fix virtio_net xmit of freed skb bug
Obvious misc patch been in my queue (& linux-next) for over a cycle.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
To prepare for virtio_ring transport feature bits, hook in a call in
all the users to manipulate them. This currently just clears all the
bits, since it doesn't understand any features.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Rather than explicitly handing the features to the lower-level, we just
hand the virtio_device and have it set the features. This make it clear
that it has the chance to manipulate the features of the device at this
point (and that all feature negotiation is already done).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We assign feature bits as required, but it makes sense to reserve some
for the particular transport, rather than the particular device.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This patch enables virtio_console as the default console on kvm for
s390. We currently use the same notify hack as lguest for early
console output. I will try to address this for lguest and s390 later.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
I also added a small Kconfig change that allows the user to specify the
virtio console in menuconfig.
(Fixes to export symbols from Stephen Rothwell <sfr@canb.auug.org.au>)
(Fixes for CONFIG_VIRTIO_CONSOLE=y vs CONFIG_VIRTIO=m from Christian himself)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
This patch exploits the new notifier callbacks of the hvc_console. We can
use the virtio callbacks instead of the polling code.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This patch tries to change hvc_console to not use request_irq/free_irq if
the backend does not use irqs. This allows virtio_console to use hvc_console
without having a linker reference to request_irq/free_irq.
In addition, together with patch 2/3 it improves the performance for virtio
console input. (an earlier version of this patch was tested by Yajin on lguest)
The irq specific code is moved to hvc_irq.c and selected by the drivers that
use irqs (System p, System i, XEN).
I replaced "int irq" with the opaque "int data". The request_irq and
free_irq calls are replaced with notifier_add and notifier_del. I have also
changed the code a bit to call the notifier_add and notifier_del inside the
spinlock area as the callbacks are found via hp->ops.
Changes since last version:
o remove ifdef
o reintroduce "irq_requested" as "notified"
o cleanups, sparse..
I did not move the timer based polling into a separate polling scheme. I
played with several variants, but it seems we need to sleep/schedule in
a thread even for irq based consoles, as there are throttleing and buffer
size constraints.
I also kept hvc_struct defined in hvc_console.h so that hvc_irq.c can access
the irq_requested element.
Feedback is appreciated. virtio_console is currently the only available console
for kvm on s390. I plan to push this change as soon as all affected parties
agree on it. I would love to get test results from System p, Xen etc.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Currently virtio_blk assumes a 512 byte hard sector size. This can cause
trouble / performance issues if the backing has a different block size
(like a file on an ext3 file system formatted with 4k block size or a dasd).
Lets add a feature flag that tells the guest to use a different hard sector
size than 512 byte.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Hook up to the probe() and remove() methods in bus_type
rather than device_driver. The latter has been preferred
since 2.6.16.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We force notification when the ring is full, even if the host has
indicated it doesn't want to know. This seemed like a good idea at
the time: if we fill the transmit ring, we should tell the host
immediately.
Unfortunately this logic also applies to the receiving ring, which is
refilled constantly. We should introduce real notification thesholds
to replace this logic. Meanwhile, removing the logic altogether breaks
the heuristics which KVM uses, so we use a hack: only notify if there are
outgoing parts of the new buffer.
Here are the number of exits with lguest's crappy network implementation:
Before:
network xmit 7859051 recv 236420
After:
network xmit 7858610 recv 118136
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We want others to implement and use virtio, so it makes sense to BSD
license the non-__KERNEL__ parts of the headers to make this crystal
clear.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Mark McLoughlin <markmc@redhat.com>
Acked-by: Ryan Harper <ryanh@us.ibm.com>
Acked-by: Eric Van Hensbergen <ericvh@gmail.com>
Acked-by: Anthony Liguori <aliguori@us.ibm.com>
If we hack the virtio_net driver to always allocate full-sized (64k+)
skbuffs, the driver slows down (lguest numbers):
Time to receive 1GB (small buffers): 10.85 seconds
Time to receive 1GB (64k+ buffers): 24.75 seconds
Of course, large buffers use up more space in the ring, so we increase
that from 128 to 2048:
Time to receive 1GB (64k+ buffers, 2k ring): 16.61 seconds
If we recycle pages rather than using alloc_page/free_page:
Time to receive 1GB (64k+ buffers, 2k ring, recycle pages): 10.81 seconds
This demonstrates that with efficient allocation, we don't need to
have a separate "small buffer" queue.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Finally this patch lets virtio_net receive GSO packets in addition
to sending them. This can definitely be optimised for the non-GSO
case. For comparison the Xen approach stores one page in each skb
and uses subsequent skb's pages to construct an SG skb instead of
preallocating the maximum amount of pages per skb.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (added feature bits)
This patch adds some basic ethtool operations to virtio_net so
I could test SG without GSO (which was really useful because TSO
turned out to be buggy :)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (remove MTU setting)
On Mon, 2008-05-26 at 17:42 +1000, Rusty Russell wrote:
> If we fail to transmit a packet, we assume the queue is full and put
> the skb into last_xmit_skb. However, if more space frees up before we
> xmit it, we loop, and the result can be transmitting the same skb twice.
>
> Fix is simple: set skb to NULL if we've used it in some way, and check
> before sending.
...
> diff -r 564237b31993 drivers/net/virtio_net.c
> --- a/drivers/net/virtio_net.c Mon May 19 12:22:00 2008 +1000
> +++ b/drivers/net/virtio_net.c Mon May 19 12:24:58 2008 +1000
> @@ -287,21 +287,25 @@ again:
> free_old_xmit_skbs(vi);
>
> /* If we has a buffer left over from last time, send it now. */
> - if (vi->last_xmit_skb) {
> + if (unlikely(vi->last_xmit_skb)) {
> if (xmit_skb(vi, vi->last_xmit_skb) != 0) {
> /* Drop this skb: we only queue one. */
> vi->dev->stats.tx_dropped++;
> kfree_skb(skb);
> + skb = NULL;
> goto stop_queue;
> }
> vi->last_xmit_skb = NULL;
With this, may drop an skb and then later in the function discover that
we could have sent it after all. Poor wee skb :)
How about the incremental patch below?
Cheers,
Mark.
Subject: [PATCH] virtio_net: Delay dropping tx skbs
Currently we drop the skb in start_xmit() if we have a
queued buffer and fail to transmit it.
However, if we delay dropping it until we've stopped the
queue and enabled the tx notification callback, then there
is a chance space might become available for it.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This fixes the following compile error caused by commit
f9247273cb ("UFS: add const to parser
token table"):
CC fs/nfs/nfsroot.o
/home/bunk/linux/kernel-2.6/git/linux-2.6/fs/nfs/nfsroot.c:130: error: tokens causes a section type conflict
make[3]: *** [fs/nfs/nfsroot.o] Error 1
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
..otherwise oprofile will fall back on that poor timer interrupt.
Also replace the unreadable chain of if-statements with a "switch()"
statement instead. It generates better code, and is a lot clearer.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Suresh Siddha wants to fix a possible FPU leakage in error conditions,
but the fact that save/restore_i387() are inlines in a header file makes
that harder to do than necessary. So start off with an obvious cleanup.
This just moves the x86-64 version of save/restore_i387() out of the
header file, and moves it to the only file that it is actually used in:
arch/x86/kernel/signal_64.c. So exposing it in a header file was wrong
to begin with.
[ Side note: I'd like to fix up some of the games we play with the
32-bit version of these functions too, but that's a separate
matter. The 32-bit versions are shared - under different names
at that! - by both the native x86-32 code and the x86-64 32-bit
compatibility code ]
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6: (76 commits)
ide: use proper printk() KERN_* levels in ide-probe.c
ide: fix for EATA SCSI HBA in ATA emulating mode
ide: remove stale comments from drivers/ide/Makefile
ide: enable local IRQs in all handlers for TASKFILE_NO_DATA data phase
ide-scsi: remove kmalloced struct request
ht6560b: remove old history
ht6560b: update email address
ide-cd: fix oops when using growisofs
gayle: release resources on ide_host_add() failure
palm_bk3710: add UltraDMA/100 support
ide: trivial sparse annotations
ide: ide-tape.c sparse annotations and unaligned access removal
ide: drop 'name' parameter from ->init_chipset method
ide: prefix messages from IDE PCI host drivers by driver name
it821x: remove DECLARE_ITE_DEV() macro
it8213: remove DECLARE_ITE_DEV() macro
ide: include PCI device name in messages from IDE PCI host drivers
ide: remove <asm/ide.h> for some archs
ide-generic: remove ide_default_{io_base,irq}() inlines (take 3)
ide-generic: is no longer needed on ppc32
...
* 'release-2.6.27' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-acpi-2.6:
acpi: fix crash in core ACPI code, triggered by CONFIG_ACPI_PCI_SLOT=y
ACPI: thinkpad-acpi: don't misdetect in get_thinkpad_model_data() on -ENOMEM
ACPI: thinkpad-acpi: bump up version to 0.21
ACPI: thinkpad-acpi: add bluetooth and WWAN rfkill support
ACPI: thinkpad-acpi: WLSW overrides other rfkill switches
ACPI: thinkpad-acpi: prepare for bluetooth and wwan rfkill support
ACPI: thinkpad-acpi: consolidate wlsw notification function
ACPI: thinkpad-acpi: minor refactor on radio switch init
Revert "ACPI: don't walk tables if ACPI was disabled"
Revert "dock: bay: Don't call acpi_walk_namespace() when ACPI is disabled."
Revert "Fix FADT parsing"
ACPI : Set FAN device to correct state in boot phase
ACPI: Ignore _BQC object when registering backlight device
ACPI: stop complaints about interrupt link End Tags and blank IRQ descriptors
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
PCI: fixup sparse endianness warnings in proc.c
PCI PM: make more PCI PM core functionality available to drivers
PCI/DMAR: don't assume presence of RMRRs
PCI hotplug: fix error path in pci_slot's register_slot
IDE probing code used to skip devices attached to EATA SCSI HBA
in ATA emulating mode but because of warm-plug support port I/O
resources are no longer freed if no devices are detected on a port
and the decision about the driver to use is left up to the user.
Remove no longer valid EATA SCSI HBA quirk from do_identify().
Noticed-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
It is already done by task_no_data_intr() and there is no reason
not to do it in other TASKFILE_NO_DATA data phase handlers.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
This converts ide-scsi to use blk_get/put_request instead of
kmalloc/kfree.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Remove the ancient version history. Git does a better job.
From: Jan Evert van Grootheest <j.e.van.grootheest@caiway.nl>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
cdrom_read_capacity() will blindly return the capacity from the device
without sanity-checking it. This later causes code in fs/buffer.c to
oops.
Fix this by checking that the device is telling us sensible things.
From: Jens Axboe <jens.axboe@oracle.com>
Cc: Michael Buesch <mb@bu3sch.de>
Cc: Jan Kara <jack@suse.cz>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: <stable@kernel.org>
Cc: Borislav Petkov <petkovbb@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[bart: print device name instead of driver name]
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
[harvey: blocklen is a big-endian value]
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
"gayle: reserve memory resources at once" patch temporary removed
freeing of resources on failure (to ease convertion to ide_host_add()
interface). This patch fixes it.
Thanks to Geert for noticing the issue.
Noticed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
