Skip to content

Q
qemu

openeuler / qemu

通知 10
Star 0
Fork 0
Q
qemu

体验新版 GitCode，发现更多精彩内容 >>

切换分支/标签
  1. 16 9月, 2019 5 次提交
  3. 03 9月, 2019 9 次提交
  5. 21 8月, 2019 1 次提交
  7. 20 8月, 2019 1 次提交
    • P
      memory: fix race between TCG and accesses to dirty bitmap · 9458a9a1
      由 Paolo Bonzini 提交于 
      There is a race between TCG and accesses to the dirty log:

      vCPU thread                  reader thread
      -----------------------      -----------------------
      TLB check -> slow path
        notdirty_mem_write
          write to RAM
          set dirty flag
                                   clear dirty flag
      TLB check -> fast path
                                   read memory
        write to RAM

Fortunately, in order to fix it, no change is required to the
vCPU thread.  However, the reader thread must delay the read after
the vCPU thread has finished the write.  This can be approximated
conservatively by run_on_cpu, which waits for the end of the current
translation block.

A similar technique is used by KVM, which has to do a synchronous TLB
flush after doing a test-and-clear of the dirty-page flags.
Reported-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      9458a9a1
  9. 16 8月, 2019 2 次提交
  11. 15 7月, 2019 2 次提交
    • P
      memory: Introduce memory listener hook log_clear() · 077874e0
      由 Peter Xu 提交于 
      Introduce a new memory region listener hook log_clear() to allow the
listeners to hook onto the points where the dirty bitmap is cleared by
the bitmap users.

Previously log_sync() contains two operations:

  - dirty bitmap collection, and,
  - dirty bitmap clear on remote site.

Let's take KVM as example - log_sync() for KVM will first copy the
kernel dirty bitmap to userspace, and at the same time we'll clear the
dirty bitmap there along with re-protecting all the guest pages again.

We add this new log_clear() interface only to split the old log_sync()
into two separated procedures:

  - use log_sync() to collect the collection only, and,
  - use log_clear() to clear the remote dirty bitmap.

With the new interface, the memory listener users will still be able
to decide how to implement the log synchronization procedure, e.g.,
they can still only provide log_sync() method only and put all the two
procedures within log_sync() (that's how the old KVM works before
KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 is introduced).  However with this
new interface the memory listener users will start to have a chance to
postpone the log clear operation explicitly if the module supports.
That can really benefit users like KVM at least for host kernels that
support KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2.

There are three places that can clear dirty bits in any one of the
dirty bitmap in the ram_list.dirty_memory[3] array:

        cpu_physical_memory_snapshot_and_clear_dirty
        cpu_physical_memory_test_and_clear_dirty
        cpu_physical_memory_sync_dirty_bitmap

Currently we hook directly into each of the functions to notify about
the log_clear().
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NPeter Xu <peterx@redhat.com>
Message-Id: <20190603065056.25211-7-peterx@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>
      077874e0
    • P
      memory: Pass mr into snapshot_and_clear_dirty · 5dea4079
      由 Peter Xu 提交于 
      Also we change the 2nd parameter of it to be the relative offset
within the memory region. This is to be used in follow up patches.
Signed-off-by: NPeter Xu <peterx@redhat.com>
Reviewed-by: NJuan Quintela <quintela@redhat.com>
Message-Id: <20190603065056.25211-6-peterx@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>
      5dea4079
  13. 06 7月, 2019 1 次提交
  15. 12 6月, 2019 2 次提交
    • M
      Include qemu-common.h exactly where needed · a8d25326
      由 Markus Armbruster 提交于 
      No header includes qemu-common.h after this commit, as prescribed by
qemu-common.h's file comment.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <20190523143508.25387-5-armbru@redhat.com>
[Rebased with conflicts resolved automatically, except for
include/hw/arm/xlnx-zynqmp.h hw/arm/nrf51_soc.c hw/arm/msf2-soc.c
block/qcow2-refcount.c block/qcow2-cluster.c block/qcow2-cache.c
target/arm/cpu.h target/lm32/cpu.h target/m68k/cpu.h target/mips/cpu.h
target/moxie/cpu.h target/nios2/cpu.h target/openrisc/cpu.h
target/riscv/cpu.h target/tilegx/cpu.h target/tricore/cpu.h
target/unicore32/cpu.h target/xtensa/cpu.h; bsd-user/main.c and
net/tap-bsd.c fixed up]
      a8d25326
    • M
      qemu-common: Move tcg_enabled() etc. to sysemu/tcg.h · 14a48c1d
      由 Markus Armbruster 提交于 
      Other accelerators have their own headers: sysemu/hax.h, sysemu/hvf.h,
sysemu/kvm.h, sysemu/whpx.h.  Only tcg_enabled() & friends sit in
qemu-common.h.  This necessitates inclusion of qemu-common.h into
headers, which is against the rules spelled out in qemu-common.h's
file comment.

Move tcg_enabled() & friends into their own header sysemu/tcg.h, and
adjust #include directives.

Cc: Richard Henderson <rth@twiddle.net>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <20190523143508.25387-2-armbru@redhat.com>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
[Rebased with conflicts resolved automatically, except for
accel/tcg/tcg-all.c]
      14a48c1d
  17. 26 4月, 2019 3 次提交
  19. 25 4月, 2019 1 次提交
  21. 19 4月, 2019 2 次提交
    • M
      qom/cpu: Simplify how CPUClass:cpu_dump_state() prints · 90c84c56
      由 Markus Armbruster 提交于 
      CPUClass method dump_statistics() takes an fprintf()-like callback and
a FILE * to pass to it.  Most callers pass fprintf() and stderr.
log_cpu_state() passes fprintf() and qemu_log_file.
hmp_info_registers() passes monitor_fprintf() and the current monitor
cast to FILE *.  monitor_fprintf() casts it right back, and is
otherwise identical to monitor_printf().

The callback gets passed around a lot, which is tiresome.  The
type-punning around monitor_fprintf() is ugly.

Drop the callback, and call qemu_fprintf() instead.  Also gets rid of
the type-punning, since qemu_fprintf() takes NULL instead of the
current monitor cast to FILE *.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190417191805.28198-15-armbru@redhat.com>
      90c84c56
    • M
      memory: Clean up how mtree_info() prints · b6b71cb5
      由 Markus Armbruster 提交于 
      mtree_info() takes an fprintf()-like callback and a FILE * to pass to
it, and so do its helper functions.  Passing around callback and
argument is rather tiresome.

Its only caller hmp_info_mtree() passes monitor_printf() cast to
fprintf_function and the current monitor cast to FILE *.

The type-punning is technically undefined behaviour, but works in
practice.  Clean up: drop the callback, and call qemu_printf()
instead.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190417191805.28198-9-armbru@redhat.com>
      b6b71cb5
  23. 29 3月, 2019 1 次提交
    • D
      exec: Only count mapped memory backends for qemu_getrampagesize() · 7d5489e6
      由 David Gibson 提交于 
      qemu_getrampagesize() works out the minimum host page size backing any of
guest RAM.  This is required in a few places, such as for POWER8 PAPR KVM
guests, because limitations of the hardware virtualization mean the guest
can't use pagesizes larger than the host pages backing its memory.

However, it currently checks against *every* memory backend, whether or not
it is actually mapped into guest memory at the moment.  This is incorrect.

This can cause a problem attempting to add memory to a POWER8 pseries KVM
guest which is configured to allow hugepages in the guest (e.g.
-machine cap-hpt-max-page-size=16m).  If you attempt to add non-hugepage,
you can (correctly) create a memory backend, however it (correctly) will
throw an error when you attempt to map that memory into the guest by
'device_add'ing a pc-dimm.

What's not correct is that if you then reset the guest a startup check
against qemu_getrampagesize() will cause a fatal error because of the new
memory object, even though it's not mapped into the guest.

This patch corrects the problem by adjusting find_max_supported_pagesize()
(called from qemu_getrampagesize() via object_child_foreach) to exclude
non-mapped memory backends.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NIgor Mammedov <imammedo@redhat.com>
Acked-by: NDavid Hildenbrand <david@redhat.com>
      7d5489e6
  25. 11 3月, 2019 1 次提交
    • W
      exec.c: refactor function flatview_add_to_dispatch() · 494d1997
      由 Wei Yang 提交于 
      flatview_add_to_dispatch() registers page based on the condition of
*section*, which may looks like this:

    |s|PPPPPPP|s|

where s stands for subpage and P for page.

The procedure of this function could be described as:

    - register first subpage
    - register page
    - register last subpage

This means the procedure could be simplified into these three steps
instead of a loop iteration.

This patch refactors the function into three corresponding steps and
adds some comment to clarify it.
Signed-off-by: NWei Yang <richardw.yang@linux.intel.com>
Message-Id: <20190311054252.6094-1-richardw.yang@linux.intel.com>
[Paolo: move exit before adjustment of remain.offset_within_*,
 otherwise int128_get64 fails when a region is 2^64 bytes long]
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      494d1997
  27. 06 3月, 2019 2 次提交
  29. 05 2月, 2019 2 次提交
    • M
      mmap-alloc: fix hugetlbfs misaligned length in ppc64 · 7265c2b9
      由 Murilo Opsfelder Araujo 提交于 
      The commit 7197fb40 ("util/mmap-alloc:
fix hugetlb support on ppc64") fixed Huge TLB mappings on ppc64.

However, we still need to consider the underlying huge page size
during munmap() because it requires that both address and length be a
multiple of the underlying huge page size for Huge TLB mappings.
Quote from "Huge page (Huge TLB) mappings" paragraph under NOTES
section of the munmap(2) manual:

  "For munmap(), addr and length must both be a multiple of the
  underlying huge page size."

On ppc64, the munmap() in qemu_ram_munmap() does not work for Huge TLB
mappings because the mapped segment can be aligned with the underlying
huge page size, not aligned with the native system page size, as
returned by getpagesize().

This has the side effect of not releasing huge pages back to the pool
after a hugetlbfs file-backed memory device is hot-unplugged.

This patch fixes the situation in qemu_ram_mmap() and
qemu_ram_munmap() by considering the underlying page size on ppc64.

After this patch, memory hot-unplug releases huge pages back to the
pool.

Fixes: 7197fb40Signed-off-by: NMurilo Opsfelder Araujo <muriloo@linux.ibm.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Reviewed-by: NGreg Kurz <groug@kaod.org>
      7265c2b9
    • L
      unify len and addr type for memory/address APIs · 0c249ff7
      由 Li Zhijian 提交于 
      Some address/memory APIs have different type between
'hwaddr/target_ulong addr' and 'int len'. It is very unsafe, especially
some APIs will be passed a non-int len by caller which might cause
overflow quietly.
Below is an potential overflow case:
    dma_memory_read(uint32_t len)
      -> dma_memory_rw(uint32_t len)
        -> dma_memory_rw_relaxed(uint32_t len)
          -> address_space_rw(int len) # len overflow

CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Peter Crosthwaite <crosthwaite.peter@gmail.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Peter Maydell <peter.maydell@linaro.org>
CC: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: NLi Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Reviewed-by: NStefano Garzarella <sgarzare@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      0c249ff7
  31. 04 2月, 2019 1 次提交
    • M
      mmap-alloc: fix hugetlbfs misaligned length in ppc64 · 53adb9d4
      由 Murilo Opsfelder Araujo 提交于 
      The commit 7197fb40 ("util/mmap-alloc:
fix hugetlb support on ppc64") fixed Huge TLB mappings on ppc64.

However, we still need to consider the underlying huge page size
during munmap() because it requires that both address and length be a
multiple of the underlying huge page size for Huge TLB mappings.
Quote from "Huge page (Huge TLB) mappings" paragraph under NOTES
section of the munmap(2) manual:

  "For munmap(), addr and length must both be a multiple of the
  underlying huge page size."

On ppc64, the munmap() in qemu_ram_munmap() does not work for Huge TLB
mappings because the mapped segment can be aligned with the underlying
huge page size, not aligned with the native system page size, as
returned by getpagesize().

This has the side effect of not releasing huge pages back to the pool
after a hugetlbfs file-backed memory device is hot-unplugged.

This patch fixes the situation in qemu_ram_mmap() and
qemu_ram_munmap() by considering the underlying page size on ppc64.

After this patch, memory hot-unplug releases huge pages back to the
pool.

Fixes: 7197fb40Signed-off-by: NMurilo Opsfelder Araujo <muriloo@linux.ibm.com>
Reviewed-by: NGreg Kurz <groug@kaod.org>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
      53adb9d4
  33. 01 2月, 2019 1 次提交
    • P
      exec.c: Don't reallocate IOMMUNotifiers that are in use · 5601be3b
      由 Peter Maydell 提交于 
      The tcg_register_iommu_notifier() code has a GArray of
TCGIOMMUNotifier structs which it has registered by passing
memory_region_register_iommu_notifier() a pointer to the embedded
IOMMUNotifier field. Unfortunately, if we need to enlarge the
array via g_array_set_size() this can cause a realloc(), which
invalidates the pointer that memory_region_register_iommu_notifier()
put into the MemoryRegion's iommu_notify list. This can result
in segfaults.

Switch the GArray to holding pointers to the TCGIOMMUNotifier
structs, so that we can individually allocate and free them.

Cc: qemu-stable@nongnu.org
Fixes: 1f871c5e ("exec.c: Handle IOMMUs in address_space_translate_for_iotlb()")
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20190128174241.5860-1-peter.maydell@linaro.org
      5601be3b
  35. 29 1月, 2019 2 次提交
  37. 11 1月, 2019 1 次提交