qemu/hw
Vincenzo Maffione e9845f0985 e1000: add interrupt mitigation support
This patch partially implements the e1000 interrupt mitigation mechanisms.
Using a single QEMUTimer, it emulates the ITR register (which is the newer
mitigation register, recommended by Intel) and approximately emulates
RADV and TADV registers. TIDV and RDTR register functionalities are not
emulated (RDTR is only used to validate RADV, according to the e1000 specs).

RADV, TADV, TIDV and RDTR registers make up the older e1000 mitigation
mechanism and would need a timer each to be completely emulated. However,
a single timer has been used in order to reach a good compromise between
emulation accuracy and simplicity/efficiency.

The implemented mechanism can be enabled/disabled specifying the command
line e1000-specific boolean parameter "mitigation", e.g.

    qemu-system-x86_64 -device e1000,mitigation=on,... ...

For more information, see the Software developer's manual at
http://download.intel.com/design/network/manuals/8254x_GBe_SDM.pdf.

Interrupt mitigation boosts performance when the guest suffers from
an high interrupt rate (i.e. receiving short UDP packets at high packet
rate). For some numerical results see the following link
http://info.iet.unipi.it/~luigi/papers/20130520-rizzo-vm.pdf

Signed-off-by: Vincenzo Maffione <v.maffione@gmail.com>
Reviewed-by: Andreas Färber <afaerber@suse.de> (for pc-* machines)
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 17:25:52 +02:00
..
9pfs virtio-9p-device: Avoid freeing uninitialized memory 2013-08-01 11:18:24 -05:00
acpi cpu: Replace qemu_for_each_cpu() 2013-09-03 12:25:55 +02:00
alpha pc,pci,virtio fixes and cleanups 2013-09-03 12:31:07 -05:00
arm QOM CPUState refactorings / X86CPU 2013-09-03 12:33:32 -05:00
audio Merge remote-tracking branch 'mjt/trivial-patches' into staging 2013-09-03 12:31:44 -05:00
block pflash_cfi02.c: fix debug macro 2013-09-01 19:32:42 +04:00
bt aio / timers: Switch entire codebase to the new timer API 2013-08-22 19:14:24 +02:00
char QOM device refactorings 2013-09-03 12:30:51 -05:00
core pc,pci,virtio fixes and cleanups 2013-09-03 12:31:07 -05:00
cpu QOM CPUState refactorings / X86CPU 2013-09-03 12:33:32 -05:00
cris hw: Clean up bogus default boot order 2013-08-28 10:16:47 +03:00
display aio / timers: Switch entire codebase to the new timer API 2013-08-22 19:14:24 +02:00
dma qom: Pass available size to object_initialize() 2013-08-30 21:15:44 +02:00
gpio gpio/zaurus: QOM cast cleanup 2013-07-29 21:06:57 +02:00
i2c exynos4210_i2c: QOM cast cleanup 2013-07-29 21:07:02 +02:00
i386 e1000: add interrupt mitigation support 2013-09-06 17:25:52 +02:00
ide qdev: Pass size to qbus_create_inplace() 2013-08-30 21:15:35 +02:00
input aio / timers: Switch entire codebase to the new timer API 2013-08-22 19:14:24 +02:00
intc QOM device refactorings 2013-09-03 12:30:51 -05:00
isa i82378: Cleanup implementation 2013-07-31 23:25:41 +02:00
lm32 hw: Clean up bogus default boot order 2013-08-28 10:16:47 +03:00
m68k hw: Clean up bogus default boot order 2013-08-28 10:16:47 +03:00
microblaze hw: Clean up bogus default boot order 2013-08-28 10:16:47 +03:00
mips pc,pci,virtio fixes and cleanups 2013-09-03 12:31:07 -05:00
misc qom: Pass available size to object_initialize() 2013-08-30 21:15:44 +02:00
moxie memory: add owner argument to initialization functions 2013-07-04 17:42:44 +02:00
net e1000: add interrupt mitigation support 2013-09-06 17:25:52 +02:00
nvram fw_cfg: the I/O port variant expects little-endian 2013-08-07 12:48:15 -05:00
openrisc pc,pci,virtio fixes and cleanups 2013-09-03 12:31:07 -05:00
pci pc,pci,virtio fixes and cleanups 2013-09-03 12:31:07 -05:00
pci-bridge i82801b11: Fix i82801b11 PCI host bridge config space 2013-08-12 12:07:12 +03:00
pci-host pc,pci,virtio fixes and cleanups 2013-09-03 12:31:07 -05:00
ppc QOM CPUState refactorings / X86CPU 2013-09-03 12:33:32 -05:00
s390x Merge remote-tracking branch 'mjt/trivial-patches' into staging 2013-09-03 12:31:44 -05:00
scsi qdev: Pass size to qbus_create_inplace() 2013-08-30 21:15:35 +02:00
sd aio / timers: Switch entire codebase to the new timer API 2013-08-22 19:14:24 +02:00
sh4 hw: Clean up bogus default boot order 2013-08-28 10:16:47 +03:00
sparc hw: Clean up bogus default boot order 2013-08-28 10:16:47 +03:00
sparc64 pc,pci,virtio fixes and cleanups 2013-09-03 12:31:07 -05:00
ssi xilinx_spi: QOM cast cleanup 2013-07-29 21:07:01 +02:00
timer misc: Fix some typos in names and comments 2013-09-01 18:59:24 +04:00
tpm aio / timers: Untangle include files 2013-08-22 19:10:27 +02:00
unicore32 hw: Clean up bogus default boot order 2013-08-28 10:16:47 +03:00
usb Merge remote-tracking branch 'kraxel/usb.88' into staging 2013-09-03 12:31:30 -05:00
virtio pc,pci,virtio fixes and cleanups 2013-09-03 12:31:07 -05:00
watchdog aio / timers: Switch entire codebase to the new timer API 2013-08-22 19:14:24 +02:00
xen devices: Associate devices to their logical category 2013-07-29 10:37:09 -05:00
xtensa pc,pci,virtio fixes and cleanups 2013-09-03 12:31:07 -05:00
Makefile.objs virtio: simplify Makefile conditionals 2013-04-19 16:18:11 +02:00