Allocating an arbitrarily-sized array of tbs results in either
(a) a lot of memory wasted or (b) unnecessary flushes of the code
cache when we run out of TB structs in the array.
An obvious solution would be to just malloc a TB struct when needed,
and keep the TB array as an array of pointers (recall that tb_find_pc()
needs the TB array to run in O(log n)).
Perhaps a better solution, which is implemented in this patch, is to
allocate TB's right before the translated code they describe. This
results in some memory waste due to padding to have code and TBs in
separate cache lines--for instance, I measured 4.7% of padding in the
used portion of code_gen_buffer when booting aarch64 Linux on a
host with 64-byte cache lines. However, it can allow for optimizations
in some host architectures, since TCG backends could safely assume that
the TB and the corresponding translated code are very close to each
other in memory. See this message by rth for a detailed explanation:
https://lists.gnu.org/archive/html/qemu-devel/2017-03/msg05172.html
Subject: Re: GSoC 2017 Proposal: TCG performance enhancements
Message-ID: <1e67644b-4b30-887e-d329-1848e94c9484@twiddle.net>
Suggested-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1496790745-314-3-git-send-email-cota@braap.org>
[rth: Simplify the arithmetic in tcg_tb_alloc]
Signed-off-by: Richard Henderson <rth@twiddle.net>
We were always passing in that one as "false" to assume that's an read
operation, and we also assume that IOMMU translation would always have
that read permission. A better permission would be IOMMU_NONE since the
replay is after all not a real read operation, but just a page table
rebuilding process.
CC: David Gibson <david@gibson.dropbear.id.au>
CC: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
This patch converts the old "is_write" bool into IOMMUAccessFlags. The
difference is that "is_write" can only express either read/write, but
sometimes what we really want is "none" here (neither read nor write).
Replay is an good example - during replay, we should not check any RW
permission bits since thats not an actual IO at all.
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
It only needed TARGET_PAGE_SIZE/BITS/BITS_MIN values, so just export
them from exec.h
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
That is the only function that we need from exec.c, and having to
include the whole sysemu.h for this.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
/me leans to be less sloppy with copyright notices
thanks Dave
To dump information about ramblocks. It looks like:
(qemu) info ramblock
Block Name PSize Offset Used Total
/objects/mem 2 MiB 0x0000000000000000 0x0000000080000000 0x0000000080000000
vga.vram 4 KiB 0x0000000080060000 0x0000000001000000 0x0000000001000000
/rom@etc/acpi/tables 4 KiB 0x00000000810b0000 0x0000000000020000 0x0000000000200000
pc.bios 4 KiB 0x0000000080000000 0x0000000000040000 0x0000000000040000
0000:00:03.0/e1000.rom 4 KiB 0x0000000081070000 0x0000000000040000 0x0000000000040000
pc.rom 4 KiB 0x0000000080040000 0x0000000000020000 0x0000000000020000
0000:00:02.0/vga.rom 4 KiB 0x0000000081060000 0x0000000000010000 0x0000000000010000
/rom@etc/table-loader 4 KiB 0x00000000812b0000 0x0000000000001000 0x0000000000001000
/rom@etc/acpi/rsdp 4 KiB 0x00000000812b1000 0x0000000000001000 0x0000000000001000
Ramblock is something hidden internally in QEMU implementation, and this
command should only be used by mostly QEMU developers on RAM stuff. It
is not a command suitable for QMP interface. So only HMP interface is
provided for it.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1494562661-9063-4-git-send-email-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Both the ram bitmap and the unsent bitmap are split by RAMBlock.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
--
Fix compilation when DEBUG_POSTCOPY is enabled (thanks Hailiang)
Xen 2017/04/21 + fix
# gpg: Signature made Tue 25 Apr 2017 19:10:37 BST
# gpg: using RSA key 0x894F8F4870E1AE90
# gpg: Good signature from "Stefano Stabellini <stefano.stabellini@eu.citrix.com>"
# gpg: aka "Stefano Stabellini <sstabellini@kernel.org>"
# Primary key fingerprint: D04E 33AB A51F 67BA 07D3 0AEA 894F 8F48 70E1 AE90
* remotes/sstabellini/tags/xen-20170421-v2-tag: (21 commits)
move xen-mapcache.c to hw/i386/xen/
move xen-hvm.c to hw/i386/xen/
move xen-common.c to hw/xen/
add xen-9p-backend to MAINTAINERS under Xen
xen/9pfs: build and register Xen 9pfs backend
xen/9pfs: send responses back to the frontend
xen/9pfs: implement in/out_iov_from_pdu and vmarshal/vunmarshal
xen/9pfs: receive requests from the frontend
xen/9pfs: connect to the frontend
xen/9pfs: introduce Xen 9pfs backend
9p: introduce a type for the 9p header
xen: import ring.h from xen
configure: use pkg-config for obtaining xen version
xen: additionally restrict xenforeignmemory operations
xen: use libxendevice model to restrict operations
xen: use 5 digit xen versions
xen: use libxendevicemodel when available
configure: detect presence of libxendevicemodel
xen: create wrappers for all other uses of xc_hvm_XXX() functions
xen: rename xen_modified_memory() to xen_hvm_modified_memory()
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This patch adds support for getting and using a local copy of the dirty
bitmap.
memory_region_snapshot_and_clear_dirty() will create a snapshot of the
dirty bitmap for the specified range, clear the dirty bitmap and return
the copy. The returned bitmap can be a bit larger than requested, the
range is expanded so the code can copy unsigned longs from the bitmap
and avoid atomic bit update operations.
memory_region_snapshot_get_dirty() will return the dirty status of
pages, pretty much like memory_region_get_dirty(), but using the copy
returned by memory_region_copy_and_clear_dirty().
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 20170421091632.30900-3-kraxel@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
migration/next for 20170421
# gpg: Signature made Fri 21 Apr 2017 11:28:13 BST
# gpg: using RSA key 0xF487EF185872D723
# gpg: Good signature from "Juan Quintela <quintela@redhat.com>"
# gpg: aka "Juan Quintela <quintela@trasno.org>"
# Primary key fingerprint: 1899 FF8E DEBF 58CC EE03 4B82 F487 EF18 5872 D723
* remotes/juanquintela/tags/migration/20170421: (65 commits)
hmp: info migrate_parameters format tunes
hmp: info migrate_capability format tunes
migration: rename max_size to threshold_size
migration: set current_active_state once
virtio-rng: stop virtqueue while the CPU is stopped
migration: don't close a file descriptor while it can be in use
ram: Remove migration_bitmap_extend()
migration: Disable hotplug/unplug during migration
qdev: Move qdev_unplug() to qdev-monitor.c
qdev: Export qdev_hot_removed
qdev: qdev_hotplug is really a bool
migration: Remove MigrationState parameter from migration_is_idle()
ram: Use RAMBitmap type for coherence
ram: rename last_ram_offset() last_ram_pages()
ram: Use ramblock and page offset instead of absolute offset
ram: Change offset field in PageSearchStatus to page
ram: Remember last_page instead of last_offset
ram: Use page number instead of an address for the bitmap operations
ram: reorganize last_sent_block
ram: ram_discard_range() don't use the mis parameter
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
We change the meaning of start to be the offset from the beggining of
the block.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
