gwj / at91sam9263 · Commits

  • Add map client retry notification (Avi Kivity) ...
    ba223c29 
    The target memory mapping API may fail if the bounce buffer resources
are exhausted.  Add a notification mechanism to allow clients to retry
the mapping operation when resources become available again.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6395 c046a42c-6fe2-441c-8c8c-71466251a162
    aliguori authored
     
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  • Add target memory mapping API (Avi Kivity) ...
    6d16c2f8 
    Devices accessing large amounts of memory (as with DMA) will wish to obtain
a pointer to guest memory rather than access it indirectly via
cpu_physical_memory_rw().  Add a new API to convert target addresses to
host pointers.

In case the target address does not correspond to RAM, a bounce buffer is
allocated.  To prevent the guest from causing the host to allocate unbounded
amounts of bounce buffer, this memory is limited (currently to one page).

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6394 c046a42c-6fe2-441c-8c8c-71466251a162
    aliguori authored
     
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  • KVM: Coalesced MMIO support ...
    f65ed4c1 
    MMIO exits are more expensive in KVM or Xen than in QEMU because they 
involve, at least, privilege transitions.  However, MMIO write 
operations can be effectively batched if those writes do not have side 
effects.

Good examples of this include VGA pixel operations when in a planar 
mode.  As it turns out, we can get a nice boost in other areas too.  
Laurent mentioned a 9.7% performance boost in iperf with the coalesced 
MMIO changes for the e1000 when he originally posted this work for KVM.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5961 c046a42c-6fe2-441c-8c8c-71466251a162
    aliguori authored
     
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  • linux-user: Fix h2g usage in page_find_alloc ...
    fb1c2cd7 
    Paul's comment on my first approach to fix the h2g usage in
page_find_alloc finally open my eyes about what the code is actually
supposed to do:

With the help of h2g_valid we can no cleanly check if a freshly allocate
page (for host usage) is guest-reachable and, in case it is, mark it
reserved in the guest's address range.

Signed-off-by: Jan Kiszka <jan.kiszka@web.de>
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Acked-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5957 c046a42c-6fe2-441c-8c8c-71466251a162
    aurel32 authored
     
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  • vga optimization (Glauber Costa) ...
    2bec46dc 
    Hypervisors like KVM perform badly while doing mmio on
a loop, because it'll generate an exit on each access.
This is the case with VGA, which results in very bad
performance.

In this patch, we map the linear frame buffer as RAM,
make sure it has dirty region tracking enabled, and then
just let the region to be written.

Cleanups suggestions by:
  Stefano Stabellini <stefano.stabellini@eu.citrix.com>

Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5793 c046a42c-6fe2-441c-8c8c-71466251a162
    aliguori authored
     
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  • Add KVM support to QEMU ...
    7ba1e619 
    This patch adds very basic KVM support.  KVM is a kernel module for Linux that
allows userspace programs to make use of hardware virtualization support.  It
current supports x86 hardware virtualization using Intel VT-x or AMD-V.  It
also supports IA64 VT-i, PPC 440, and S390.

This patch only implements the bare minimum support to get a guest booting.  It
has very little impact the rest of QEMU and attempts to integrate nicely with
the rest of QEMU.

Even though this implementation is basic, it is significantly faster than TCG.
Booting and shutting down a Linux guest:

w/TCG:  1:32.36 elapsed  84% CPU

w/KVM:  0:31.14 elapsed  59% CPU

Right now, KVM is disabled by default and must be explicitly enabled with
 -enable-kvm.  We can enable it by default later when we have had better
testing.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5627 c046a42c-6fe2-441c-8c8c-71466251a162
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