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author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-01-23 10:00:18 +0400 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-01-23 10:00:18 +0400 |
commit | 84621c9b18d0bb6cb267e3395c7f3131ecf4d39c (patch) | |
tree | 28566fe0211798143136b5cd154e2239d38a7b68 /include/xen/interface/event_channel.h | |
parent | 7ebd3faa9b5b42caf2d5aa1352a93dcfa0098011 (diff) | |
parent | c9f6e9977e38de15da96b732a8dec0ef56cbf977 (diff) | |
download | linux-84621c9b18d0bb6cb267e3395c7f3131ecf4d39c.tar.xz |
Merge tag 'stable/for-linus-3.14-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull Xen updates from Konrad Rzeszutek Wilk:
"Two major features that Xen community is excited about:
The first is event channel scalability by David Vrabel - we switch
over from an two-level per-cpu bitmap of events (IRQs) - to an FIFO
queue with priorities. This lets us be able to handle more events,
have lower latency, and better scalability. Good stuff.
The other is PVH by Mukesh Rathor. In short, PV is a mode where the
kernel lets the hypervisor program page-tables, segments, etc. With
EPT/NPT capabilities in current processors, the overhead of doing this
in an HVM (Hardware Virtual Machine) container is much lower than the
hypervisor doing it for us.
In short we let a PV guest run without doing page-table, segment,
syscall, etc updates through the hypervisor - instead it is all done
within the guest container. It is a "hybrid" PV - hence the 'PVH'
name - a PV guest within an HVM container.
The major benefits are less code to deal with - for example we only
use one function from the the pv_mmu_ops (which has 39 function
calls); faster performance for syscall (no context switches into the
hypervisor); less traps on various operations; etc.
It is still being baked - the ABI is not yet set in stone. But it is
pretty awesome and we are excited about it.
Lastly, there are some changes to ARM code - you should get a simple
conflict which has been resolved in #linux-next.
In short, this pull has awesome features.
Features:
- FIFO event channels. Key advantages: support for over 100,000
events (2^17), 16 different event priorities, improved fairness in
event latency through the use of FIFOs.
- Xen PVH support. "It’s a fully PV kernel mode, running with
paravirtualized disk and network, paravirtualized interrupts and
timers, no emulated devices of any kind (and thus no qemu), no BIOS
or legacy boot — but instead of requiring PV MMU, it uses the HVM
hardware extensions to virtualize the pagetables, as well as system
calls and other privileged operations." (from "The
Paravirtualization Spectrum, Part 2: From poles to a spectrum")
Bug-fixes:
- Fixes in balloon driver (refactor and make it work under ARM)
- Allow xenfb to be used in HVM guests.
- Allow xen_platform_pci=0 to work properly.
- Refactors in event channels"
* tag 'stable/for-linus-3.14-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (52 commits)
xen/pvh: Set X86_CR0_WP and others in CR0 (v2)
MAINTAINERS: add git repository for Xen
xen/pvh: Use 'depend' instead of 'select'.
xen: delete new instances of __cpuinit usage
xen/fb: allow xenfb initialization for hvm guests
xen/evtchn_fifo: fix error return code in evtchn_fifo_setup()
xen-platform: fix error return code in platform_pci_init()
xen/pvh: remove duplicated include from enlighten.c
xen/pvh: Fix compile issues with xen_pvh_domain()
xen: Use dev_is_pci() to check whether it is pci device
xen/grant-table: Force to use v1 of grants.
xen/pvh: Support ParaVirtualized Hardware extensions (v3).
xen/pvh: Piggyback on PVHVM XenBus.
xen/pvh: Piggyback on PVHVM for grant driver (v4)
xen/grant: Implement an grant frame array struct (v3).
xen/grant-table: Refactor gnttab_init
xen/grants: Remove gnttab_max_grant_frames dependency on gnttab_init.
xen/pvh: Piggyback on PVHVM for event channels (v2)
xen/pvh: Update E820 to work with PVH (v2)
xen/pvh: Secondary VCPU bringup (non-bootup CPUs)
...
Diffstat (limited to 'include/xen/interface/event_channel.h')
-rw-r--r-- | include/xen/interface/event_channel.h | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/include/xen/interface/event_channel.h b/include/xen/interface/event_channel.h index f4942921e202..7e6acef5415b 100644 --- a/include/xen/interface/event_channel.h +++ b/include/xen/interface/event_channel.h @@ -190,6 +190,39 @@ struct evtchn_reset { }; typedef struct evtchn_reset evtchn_reset_t; +/* + * EVTCHNOP_init_control: initialize the control block for the FIFO ABI. + */ +#define EVTCHNOP_init_control 11 +struct evtchn_init_control { + /* IN parameters. */ + uint64_t control_gfn; + uint32_t offset; + uint32_t vcpu; + /* OUT parameters. */ + uint8_t link_bits; + uint8_t _pad[7]; +}; + +/* + * EVTCHNOP_expand_array: add an additional page to the event array. + */ +#define EVTCHNOP_expand_array 12 +struct evtchn_expand_array { + /* IN parameters. */ + uint64_t array_gfn; +}; + +/* + * EVTCHNOP_set_priority: set the priority for an event channel. + */ +#define EVTCHNOP_set_priority 13 +struct evtchn_set_priority { + /* IN parameters. */ + uint32_t port; + uint32_t priority; +}; + struct evtchn_op { uint32_t cmd; /* EVTCHNOP_* */ union { @@ -207,4 +240,39 @@ struct evtchn_op { }; DEFINE_GUEST_HANDLE_STRUCT(evtchn_op); +/* + * 2-level ABI + */ + +#define EVTCHN_2L_NR_CHANNELS (sizeof(xen_ulong_t) * sizeof(xen_ulong_t) * 64) + +/* + * FIFO ABI + */ + +/* Events may have priorities from 0 (highest) to 15 (lowest). */ +#define EVTCHN_FIFO_PRIORITY_MAX 0 +#define EVTCHN_FIFO_PRIORITY_DEFAULT 7 +#define EVTCHN_FIFO_PRIORITY_MIN 15 + +#define EVTCHN_FIFO_MAX_QUEUES (EVTCHN_FIFO_PRIORITY_MIN + 1) + +typedef uint32_t event_word_t; + +#define EVTCHN_FIFO_PENDING 31 +#define EVTCHN_FIFO_MASKED 30 +#define EVTCHN_FIFO_LINKED 29 +#define EVTCHN_FIFO_BUSY 28 + +#define EVTCHN_FIFO_LINK_BITS 17 +#define EVTCHN_FIFO_LINK_MASK ((1 << EVTCHN_FIFO_LINK_BITS) - 1) + +#define EVTCHN_FIFO_NR_CHANNELS (1 << EVTCHN_FIFO_LINK_BITS) + +struct evtchn_fifo_control_block { + uint32_t ready; + uint32_t _rsvd; + event_word_t head[EVTCHN_FIFO_MAX_QUEUES]; +}; + #endif /* __XEN_PUBLIC_EVENT_CHANNEL_H__ */ |