Commit Graph

379 Commits

Author SHA1 Message Date
Peter Crosthwaite e1b89321ba include/exec: Move tb hash functions out
This is one of very few things in exec-all with a genuine CPU
architecture dependency. Move these hashing helpers to a new
header to trim exec-all.h down to a near architecture-agnostic
header.

The defs are only used by cpu-exec and translate-all which are both
arch-obj's so the new tb-hash.h has no core code usage.

Reviewed-by: Richard Henderson <rth@redhat.com>
Signed-off-by: Peter Crosthwaite <crosthwaite.peter@gmail.com>
Message-Id: <9d048b96f7cfa64a4d9c0b88e0dd2877fac51d41.1433052532.git.crosthwaite.peter@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-26 16:00:51 +02:00
Peter Maydell 73104fd399 - vhost-scsi: add bootindex property
- RCU: fix MemoryRegion lifetime issues in PCI; document the rules;
 convert of AddressSpaceDispatch and RAMList
 - KVM: add kvm_exit reasons for aarch64
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

- vhost-scsi: add bootindex property
- RCU: fix MemoryRegion lifetime issues in PCI; document the rules;
convert of AddressSpaceDispatch and RAMList
- KVM: add kvm_exit reasons for aarch64

# gpg: Signature made Mon Feb 16 16:32:32 2015 GMT using RSA key ID 78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4  E2F7 7E15 100C CD36 69B1
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* remotes/bonzini/tags/for-upstream: (21 commits)
  Convert ram_list to RCU
  exec: convert ram_list to QLIST
  cosmetic changes preparing for the following patches
  exec: protect mru_block with RCU
  rcu: add g_free_rcu
  rcu: introduce RCU-enabled QLIST
  exec: RCUify AddressSpaceDispatch
  exec: make iotlb RCU-friendly
  exec: introduce cpu_reload_memory_map
  docs: clarify memory region lifecycle
  pci: split shpc_cleanup and shpc_free
  pcie: remove mmconfig memory leak and wrap mmconfig update with transaction
  memory: keep the owner of the AddressSpace alive until do_address_space_destroy
  rcu: run RCU callbacks under the BQL
  rcu: do not let RCU callbacks pile up indefinitely
  vhost-scsi: set the bootable value of channel/target/lun
  vhost-scsi: add a property for booting
  vhost-scsi: expose the TYPE_FW_PATH_PROVIDER interface
  vhost-scsi: add bootindex property
  qdev: support to get a device firmware path directly
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-02-24 13:58:18 +00:00
Paolo Bonzini 79e2b9aecc exec: RCUify AddressSpaceDispatch
Note that even after this patch, most callers of address_space_*
functions must still be under the big QEMU lock, otherwise the memory
region returned by address_space_translate can disappear as soon as
address_space_translate returns.  This will be fixed in the next part
of this series.

Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-02-16 17:30:19 +01:00
Paolo Bonzini 9d82b5a792 exec: make iotlb RCU-friendly
After the previous patch, TLBs will be flushed on every change to
the memory mapping.  This patch augments that with synchronization
of the MemoryRegionSections referred to in the iotlb array.

With this change, it is guaranteed that iotlb_to_region will access
the correct memory map, even once the TLB will be accessed outside
the BQL.

Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-02-16 17:30:19 +01:00
Paolo Bonzini 76e5c76f2e exec: introduce cpu_reload_memory_map
This for now is a simple TLB flush.  This can change later for two
reasons:

1) an AddressSpaceDispatch will be cached in the CPUState object

2) it will not be possible to do tlb_flush once the TCG-generated code
runs outside the BQL.

Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-02-16 17:30:19 +01:00
Paolo Bonzini 52851b7e3d cpu-exec: simplify icount code
Use MIN instead of an "if" statement.  Move "tb" assignment where
the value is actually used.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-02-10 09:27:20 +03:00
Paolo Bonzini a7fa2e9783 cpu-exec: drop dead assignment
All uses of TB inside cpu_exec are dominated by "tb = tb_find_fast(env)",
and there are no uses after the switch statement.  So the assignment
is dead, as reported by Coverity.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-02-10 09:27:20 +03:00
Paolo Bonzini 2e91cc62f2 cpu-exec: simplify init_delay_params
With the introduction of QEMU_CLOCK_VIRTUAL_RT, the computation of
sc->diff_clk can be simplified nicely:

        qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) -
        qemu_clock_get_ns(QEMU_CLOCK_REALTIME) +
        cpu_get_clock_offset()

     =  qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) -
        (qemu_clock_get_ns(QEMU_CLOCK_REALTIME) - cpu_get_clock_offset())

     =  qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) -
        (qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + timers_state.cpu_clock_offset)

     =  qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) -
        qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL_RT)

Cc: Sebastian Tanase <sebastian.tanase@openwide.fr>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-02-02 16:55:11 +01:00
Paolo Bonzini a498d0ef37 cpu-exec: simplify align_clocks
sc->diff_clk is already equal to sleep_delay (split in a second and a
nanosecond part).  If you subtract sleep_delay - rem_delay, the result
is exactly rem_delay.

Cc: Sebastian Tanase <sebastian.tanase@openwide.fr>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-02-02 16:55:11 +01:00
Pavel Dovgalyuk d8a499f17e cpu-exec: invalidate nocache translation if they are interrupted
In this case, QEMU might longjmp out of cpu-exec.c and miss the final
cleanup in cpu_exec_nocache.  Do this manually through a new compile
flag.

Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-15 12:21:02 +01:00
Pavel Dovgalyuk 626cf8f4c6 icount: set can_do_io outside TB execution
This patch sets can_do_io function to allow reading icount
within cpu-exec, but outside TB execution.

Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-15 12:21:02 +01:00
Pavel Dovgalyuk e511b4d783 cpu-exec: reset exception_index correctly
Exception index is reset at every entry at every entry into cpu_exec()
function. This may cause missing the exceptions while replaying them.
This patch moves exception_index reset to the locations where they are
processed.

Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-15 12:21:02 +01:00
Pavel Dovgalyuk b4ac20b4df cpu-exec: fix cpu_exec_nocache
In icount mode cpu_exec_nocache function is used to execute part of the
existing TB. At the end of cpu_exec_nocache newly created TB is deleted.
Sometimes io_read function needs to recompile current TB and restart TB
lookup and execution. After that tb_find_fast function finds old (bigger)
TB again. This TB cannot be executed (because icount is not big enough)
and cpu_exec_nocache is called again. Such a loop continues over and over.
This patch deletes old TB and avoids finding it in the TB cache.

Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-12-15 12:21:02 +01:00
Richard Henderson 6a0fcbdf2d cpu-exec: Do CPU_INTERRUPT_HALT unconditionally
The signal is currently checked by 10 targets, but only actually
raised by Sparc and ARM.  For the sake of one test-and-branch,
we can handle this generic bit generically.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-id: 1410626734-3804-24-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:22 +01:00
Richard Henderson 42f53fea9f target-i386: Use cpu_exec_interrupt qom hook
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-id: 1410626734-3804-23-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:22 +01:00
Richard Henderson 458dd76656 target-ppc: Use cpu_exec_interrupt qom hook
Cc: qemu-ppc@nongnu.org
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-id: 1410626734-3804-22-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:22 +01:00
Richard Henderson e9854c3945 target-lm32: Use cpu_exec_interrupt qom hook
Cc: Michael Walle <michael@walle.cc>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Acked-by: Michael Walle <michael@walle.cc>
Message-id: 1410626734-3804-21-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:22 +01:00
Richard Henderson 29cd33d3c7 target-microblaze: Use cpu_exec_interrupt qom hook
Cc: Edgar E. Iglesias <edgar.iglesias@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-id: 1410626734-3804-20-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:22 +01:00
Richard Henderson fa4faba448 target-mips: Use cpu_exec_interrupt qom hook
Cc: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Leon Alrae <leon.alrae@imgtec.com>
Tested-by: Leon Alrae <leon.alrae@imgtec.com>
Message-id: 1410626734-3804-19-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:22 +01:00
Richard Henderson dfdb483454 target-tricore: Remove the dummy interrupt boilerplate
It can go back in when it actually does something.

Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Message-id: 1410626734-3804-18-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:22 +01:00
Richard Henderson fbb96c4b7f target-openrisc: Use cpu_exec_interrupt qom hook
Cc: Jia Liu <proljc@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Tested-by: Jia Liu <proljc@gmail.com>
Message-id: 1410626734-3804-17-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:22 +01:00
Richard Henderson 87afe467e2 target-sparc: Use cpu_exec_interrupt qom hook
Cc: Blue Swirl <blauwirbel@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-id: 1410626734-3804-16-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:22 +01:00
Richard Henderson e8925712e6 target-arm: Use cpu_exec_interrupt qom hook
Cc: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-id: 1410626734-3804-15-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:22 +01:00
Richard Henderson d8bb915972 target-unicore32: Use cpu_exec_interrupt qom hook
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-id: 1410626734-3804-14-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:22 +01:00
Richard Henderson f47ede195b target-sh4: Use cpu_exec_interrupt qom hook
Cc: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-id: 1410626734-3804-13-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:22 +01:00
Richard Henderson dde7c241e3 target-alpha: Use cpu_exec_interrupt qom hook
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-id: 1410626734-3804-12-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:21 +01:00
Richard Henderson 5a1f7f44cf target-cris: Use cpu_exec_interrupt qom hook
Cc: Edgar E. Iglesias <edgar.iglesias@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 1410626734-3804-11-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:21 +01:00
Richard Henderson ab409bb3fe target-m68k: Use cpu_exec_interrupt qom hook
Since do_interrupt_m68k_hardirq is no longer used outside
op_helper.c, make it static.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1410626734-3804-10-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:21 +01:00
Richard Henderson 02bb9bbf1d target-s390x: Use cpu_exec_interrupt qom hook
Cc: Alexander Graf <agraf@suse.de>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1410626734-3804-9-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:21 +01:00
Richard Henderson 37f3616aa8 target-xtensa: Use cpu_exec_interrupt qom hook
Cc: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
Message-id: 1410626734-3804-8-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:21 +01:00
Richard Henderson 9585db68c7 qom: Add cpu_exec_interrupt hook
Continuing the removal of ifdefs from cpu_exec.

Cc: Andreas Färber <afaerber@suse.de>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1410626734-3804-7-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:21 +01:00
Richard Henderson 774f0abeae target-ppc: Use cpu_exec_enter qom hook
Cc: qemu-ppc@nongnu.org
Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1410626734-3804-6-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:21 +01:00
Richard Henderson 00f3fd63e1 target-m68k: Use cpu_exec_enter/exit qom hooks
Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1410626734-3804-5-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:21 +01:00
Richard Henderson 374e0cd4db target-i386: Use cpu_exec_enter/exit qom hooks
Note that the code that was within the "exit" ifdef block
was identical to the cpu_compute_eflags inline, so make that
simplification at the same time.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1410626734-3804-4-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:21 +01:00
Richard Henderson 1039e1290f cpu-exec: Remove do-nothing ifdef chains
Around the cpu_exec_enter/exit hooks contain many empty
ifdef blocks.  Delete all of these to highlight those
targets for which we actually need to do work.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1410626734-3804-3-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:21 +01:00
Richard Henderson cffe7b3249 qom: Add cpu_exec_enter and cpu_exec_exit hooks
In preparation for removing a bunch of ifdefs from cpu_exec.

Cc: Andreas Färber <afaerber@suse.de>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1410626734-3804-2-git-send-email-rth@twiddle.net
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-25 18:54:21 +01:00
Peter Maydell 86025ee443 cpu-exec: Make debug_excp_handler a QOM CPU method
Make the debug_excp_handler target specific hook into a QOM
CPU method.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-12 14:06:48 +01:00
David Hoover c3c8d6b3dd cpu-exec.c: Allow disabling of IRQs on ARM Cortex-M CPUs
Correct an error in the logic for deciding whether we can
take an IRQ interrupt which meant that on M profile cores
it was never possible to disable them.

The design here is still bogus in that M profile doesn't
have separate "IRQ" and "FIQ", which are an A/R profile
concept; we should ideally implement the proper priority
based scheme.

Signed-off-by: David Hoover <spm@boiteauxlettres.sent.at>
[PMM: Wrote a proper commit message]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-12 14:06:47 +01:00
Bastian Koppelmann 48e06fe0ed target-tricore: Add target stubs and qom-cpu
Add TriCore target stubs, and QOM cpu, and Maintainer

Signed-off-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Message-id: 1409572800-4116-2-git-send-email-kbastian@mail.uni-paderborn.de
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-09-01 14:49:20 +01:00
Alex Bennée 6db8b53866 trace: add some tcg tracing support
This adds a couple of tcg specific trace-events which are useful for
tracing execution though tcg generated blocks. It's been tested with
lttng user space tracing but is generic enough for all systems. The tcg
events are:

  * translate_block - when a subject block is translated
  * exec_tb - when a translated block is entered
  * exec_tb_exit - when we exit the translated code
  * exec_tb_nocache - special case translations

Of course we can only trace the entrance to the first block of a chain
as each block will jump directly to the next when it can. See the -d
nochain patch to allow more complete tracing at the expense of
performance.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-08-12 14:26:12 +01:00
Sebastian Tanase 27498bef35 monitor: Add drift info to 'info jit'
Show in 'info jit' the current delay between the host clock
and the guest clock. In addition, print the maximum advance
and delay of the guest compared to the host.

Signed-off-by: Sebastian Tanase <sebastian.tanase@openwide.fr>
Tested-by: Camille Bégué <camille.begue@openwide.fr>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-07 15:09:48 +02:00
Sebastian Tanase 7f7bc144ed cpu-exec: Print to console if the guest is late
If the align option is enabled, we print to the user whenever
the guest clock is behind the host clock in order for he/she
to have a hint about the actual performance. The maximum
print interval is 2s and we limit the number of messages to 100.
If desired, this can be changed in cpu-exec.c

Signed-off-by: Sebastian Tanase <sebastian.tanase@openwide.fr>
Tested-by: Camille Bégué <camille.begue@openwide.fr>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-06 17:53:07 +02:00
Sebastian Tanase c2aa5f8199 cpu-exec: Add sleeping algorithm
The goal is to sleep qemu whenever the guest clock
is in advance compared to the host clock (we use
the monotonic clocks). The amount of time to sleep
is calculated in the execution loop in cpu_exec.

At first, we tried to approximate at each for loop the real time elapsed
while searching for a TB (generating or retrieving from cache) and
executing it. We would then approximate the virtual time corresponding
to the number of virtual instructions executed. The difference between
these 2 values would allow us to know if the guest is in advance or delayed.
However, the function used for measuring the real time
(qemu_clock_get_ns(QEMU_CLOCK_REALTIME)) proved to be very expensive.
We had an added overhead of 13% of the total run time.

Therefore, we modified the algorithm and only take into account the
difference between the 2 clocks at the begining of the cpu_exec function.
During the for loop we try to reduce the advance of the guest only by
computing the virtual time elapsed and sleeping if necessary. The overhead
is thus reduced to 3%. Even though this method still has a noticeable
overhead, it no longer is a bottleneck in trying to achieve a better
guest frequency for which the guest clock is faster than the host one.

As for the the alignement of the 2 clocks, with the first algorithm
the guest clock was oscillating between -1 and 1ms compared to the host clock.
Using the second algorithm we notice that the guest is 5ms behind the host, which
is still acceptable for our use case.

The tests where conducted using fio and stress. The host machine in an i5 CPU at
3.10GHz running Debian Jessie (kernel 3.12). The guest machine is an arm versatile-pb
built with buildroot.

Currently, on our test machine, the lowest icount we can achieve that is suitable for
aligning the 2 clocks is 6. However, we observe that the IO tests (using fio) are
slower than the cpu tests (using stress).

Signed-off-by: Sebastian Tanase <sebastian.tanase@openwide.fr>
Tested-by: Camille Bégué <camille.begue@openwide.fr>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-06 17:53:07 +02:00
Paolo Bonzini 4a92a558f4 cpu: make CPU_INTERRUPT_RESET available on all targets
On the x86, some devices need access to the CPU reset pin (INIT#).
Provide a generic service to do this, using one of the internal
cpu_interrupt targets.  Generalize the PPC-specific code for
CPU_INTERRUPT_RESET to other targets.

Since PPC does not support migration across QEMU versions (its
machine types are not versioned yet), I picked the value that
is used on x86, CPU_INTERRUPT_TGT_INT_1.  Consequently, TGT_INT_2
and TGT_INT_3 are shifted down by one while keeping their value.

Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-05-13 13:21:51 +02:00
Peter Maydell bae2c27090 cpu-exec: Unlock tb_lock if we longjmp out of code generation
If the guest attempts to execute from unreadable memory, this will
cause us to longjmp back to the main loop from inside the
target frontend decoder. For linux-user mode, this means we will
still hold the tb_ctx.tb_lock, and will deadlock when we try to
start executing code again. Unlock the lock in the return-from-longjmp
code path to avoid this.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Andrei Warkentin <andrey.warkentin@gmail.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2014-04-04 18:29:25 +01:00
Andreas Färber 0ea8cb8895 cpu-exec: Change cpu_resume_from_signal() argument to CPUState
Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-03-13 19:20:48 +01:00
Andreas Färber 648f034c6c translate-all: Change tb_gen_code() argument to CPUState
Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-03-13 19:20:48 +01:00
Andreas Färber 5638d180d6 cpu-exec: Change cpu_loop_exit() argument to CPUState
Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-03-13 19:20:47 +01:00
Andreas Färber ff4700b05c cpu: Move watchpoint fields from CPU_COMMON to CPUState
Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-03-13 19:20:47 +01:00
Andreas Färber 27103424c4 cpu: Move exception_index field from CPU_COMMON to CPUState
Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-03-13 19:20:46 +01:00