hvc_console: rework setup to replace irq functions with callbacks
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>
Rusty Russell [Fri, 25 Jul 2008 17:06:04 +0000 (12:06 -0500)]
virtio: don't always force a notification when ring is full
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>
Rusty Russell [Fri, 25 Jul 2008 17:06:03 +0000 (12:06 -0500)]
virtio: clarify that ABI is usable by any implementations
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>
Herbert Xu [Fri, 18 Apr 2008 03:24:27 +0000 (11:24 +0800)]
virtio net: Allow receiving SG packets
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)
Herbert Xu [Fri, 18 Apr 2008 03:21:42 +0000 (11:21 +0800)]
virtio net: Add ethtool ops for SG/GSO
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)
Mark McLoughlin [Tue, 27 May 2008 11:06:26 +0000 (12:06 +0100)]
virtio: fix virtio_net xmit of freed skb bug
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 :)
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>
* 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
...
Merge branch 'release-2.6.27' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-acpi-2.6
* '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
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* '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>
gayle: release resources on ide_host_add() failure
"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.
Sergei Shtylyov [Thu, 24 Jul 2008 20:53:34 +0000 (22:53 +0200)]
palm_bk3710: add UltraDMA/100 support
This controller supports UltraDMA up to mode 5 but it should be clocked with
at least twice the data strobe frequency, so enable mode 5 for 100+ MHz IDECLK.
While at it, start passing the correct device to clk_get() -- it worked anyway
but WTF? :-/
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Harvey Harrison [Thu, 24 Jul 2008 20:53:33 +0000 (22:53 +0200)]
ide: ide-tape.c sparse annotations and unaligned access removal
If this is actually unaligned the access of speed/max_speed above
is already broken and needs a get_unaligned. Otherwise it is
aligned and they can be removed.
ide: prefix messages from IDE PCI host drivers by driver name
Prefix messages from IDE PCI host drivers by driver name instead of marketed
chipset name (it is still possible to exactly identify the particular chipset
basing on driver messages).
As a bonus this provides nice code savings for some drivers:
* Now that ide_hwif_t instances are allocated dynamically
the difference between MAX_HWIFS == 2 and MAX_HWIFS == 10
is ~100 bytes (x86-32) so use MAX_HWIFS == 10 on all archs
except these ones that use MAX_HWIFS == 1.
* Define MAX_HWIFS in <linux/ide.h> instead of <asm/ide.h>.
[ Please note that avr32/cris/v850 have no <asm/ide.h>
and alpha/ia64/sh always define CONFIG_IDE_MAX_HWIFS. ]
Move ide_probe_legacy() call to ide_generic_init() so it fails
early if necessary and returns the proper error value (nowadays
ide_default_io_base() is used only by ide-generic).
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
MAINTAINERS: Remove Glenn Streiff from NetEffect entry
mlx4_core: Improve error message when not enough UAR pages are available
IB/mlx4: Add support for memory management extensions and local DMA L_Key
IB/mthca: Keep free count for MTT buddy allocator
mlx4_core: Keep free count for MTT buddy allocator
mlx4_code: Add missing FW status return code
IB/mlx4: Rename struct mlx4_lso_seg to mlx4_wqe_lso_seg
mlx4_core: Add module parameter to enable QoS support
RDMA/iwcm: Remove IB_ACCESS_LOCAL_WRITE from remote QP attributes
IPoIB: Include err code in trace message for ib_sa_path_rec_get() failures
IB/sa_query: Check if sm_ah is NULL in ib_sa_remove_one()
IB/ehca: Release mutex in error path of alloc_small_queue_page()
IB/ehca: Use default value for Local CA ACK Delay if FW returns 0
IB/ehca: Filter PATH_MIG events if QP was never armed
IB/iser: Add support for RDMA_CM_EVENT_ADDR_CHANGE event
RDMA/cma: Add RDMA_CM_EVENT_TIMEWAIT_EXIT event
RDMA/cma: Add RDMA_CM_EVENT_ADDR_CHANGE event
Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
nohz: adjust tick_nohz_stop_sched_tick() call of s390 as well
nohz: prevent tick stop outside of the idle loop
Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
arch/mips/kernel/stacktrace.c: Heiko can't type
kthread: reduce stack pressure in create_kthread and kthreadd
fix core/stacktrace changes on avr32, mips, sh
Commit 9d25d4db81833029d30b7b03cc1000cbbe09e192 ("x86: BUILD_IRQ say
.text to avoid .data.percpu") added a ".text" specifier to make sure
that BUILD_IRQ() builds the irq trampoline in the text segment rather
than in some random left-over segment that the compiler happened to
leave the asm in.
However, we should also make sure that we switch back by adding a
".previous" at the end, so that there are no subtle issues with
subsequent compiler-generated code.
Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: fix header export, asm-x86/processor-flags.h, CONFIG_* leaks
x86: BUILD_IRQ say .text to avoid .data.percpu
xen: don't use sysret for sysexit32
x86: call early_cpu_init at the same point
Merge branch 'semaphore' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc
* 'semaphore' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc:
Remove __DECLARE_SEMAPHORE_GENERIC
Remove asm/semaphore.h
Remove use of asm/semaphore.h
Add missing semaphore.h includes
Remove mention of semaphores from kernel-locking
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
m68knommu: put ColdFire head code into .text.head section
m68knommu: remove last use of CONFIG_FADS and CONFIG_RPXCLASSIC
m68knommu: remove RPXCLASSIC from the m68k tree
m68knommu: fec: remove FADS
m68knommu: MCF5307 PIT GENERIC_CLOCKEVENTS support
m68knommu: add read_barrier_depends() and irqs_disabled_flags()
m68knommu: add byteswap assembly opcode for ISA A+
m68knommu: add ffs and __ffs plattform which support ISA A+ or ISA C
m68knommu: add sched_clock() for the DMA timer
m68knommu: complete generic time
m68knommu: move code within time.c
m68knommu: m68knommu: add old stack trace method
m68knommu: Add Coldfire DMA Timer support
m68knommu: defconfig for M5407C3 board
m68knommu: defconfig for M5307C3 board
m68knommu: defconfig for M5275EVB board
m68knommu: defconfig for M5249EVB board
m68knommu: change to a configs directory for board configurations
Merge branch 'for-linus' of git://git.o-hand.com/linux-rpurdie-leds
* 'for-linus' of git://git.o-hand.com/linux-rpurdie-leds:
leds: Ensure led->trigger is set earlier
leds: Add support for Philips PCA955x I2C LED drivers
leds: Fix sparse warnings in leds-h1940 driver
leds: mark led_classdev.default_trigger as const
leds: fix unsigned value overflow in atmel pwm driver
leds: Add pca9532 platform data for Thecus N2100
leds: Add pca9532 led driver
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
pkt_sched: sch_sfq: dump a real number of flows
atm: [fore200e] use MODULE_FIRMWARE() and other suggested cleanups
netfilter: make security table depend on NETFILTER_ADVANCED
tcp: Clear probes_out more aggressively in tcp_ack().
e1000e: fix e1000_netpoll(), remove extraneous e1000_clean_tx_irq() call
net: Update entry in af_family_clock_key_strings
netdev: Remove warning from __netif_schedule().
sky2: don't stop queue on shutdown