Commit Graph

49261 Commits

Author SHA1 Message Date
Kevin Wolf
61b2450414 block: Remove bdrv_ioctl()
It is unused now.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-10-27 19:05:23 +02:00
Kevin Wolf
0d4377b3ea raw-posix: Don't use bdrv_ioctl()
Instead of letting raw-posix use the bdrv_ioctl() abstraction to issue
an ioctl to itself, just call ioctl() directly.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-10-27 19:05:23 +02:00
Kevin Wolf
48af776a5b block: Use blk_co_ioctl() for all BB level ioctls
All read/write functions already have a single coroutine-based function
on the BlockBackend level through which all requests go (no matter what
API style the external caller used) and which passes the requests down
to the block node level.

This patch exports a bdrv_co_ioctl() function and uses it to extend this
mode of operation to ioctls.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-10-27 19:05:22 +02:00
Kevin Wolf
7381e95cc2 block: Remove bdrv_aio_pdiscard()
It is unused now.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-10-27 19:05:22 +02:00
Kevin Wolf
8c2e3dd55f block: Use blk_co_pdiscard() for all BB level discard
All read/write functions already have a single coroutine-based function
on the BlockBackend level through which all requests go (no matter what
API style the external caller used) and which passes the requests down
to the block node level.

This patch extends this mode of operation to discards.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-10-27 19:05:22 +02:00
Kevin Wolf
be07a88981 block: Use blk_co_flush() for all BB level flushes
All read/write functions already have a single coroutine-based function
on the BlockBackend level through which all requests go (no matter what
API style the external caller used) and which passes the requests down
to the block node level.

This patch extends this mode of operation to flushes.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-10-27 19:05:22 +02:00
Peter Maydell
5929d7e8a0 cmpxchg emulation of atomics, v8
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Merge remote-tracking branch 'remotes/rth/tags/pull-atomic-20161026' into staging

cmpxchg emulation of atomics, v8

# gpg: Signature made Wed 26 Oct 2016 16:30:03 BST
# gpg:                using RSA key 0xAD1270CC4DD0279B
# gpg: Good signature from "Richard Henderson <rth7680@gmail.com>"
# gpg:                 aka "Richard Henderson <rth@redhat.com>"
# gpg:                 aka "Richard Henderson <rth@twiddle.net>"
# Primary key fingerprint: 9CB1 8DDA F8E8 49AD 2AFC  16A4 AD12 70CC 4DD0 279B

* remotes/rth/tags/pull-atomic-20161026: (37 commits)
  target-alpha: Emulate LL/SC using cmpxchg helpers
  target-alpha: Introduce MMU_PHYS_IDX
  target-arm: remove EXCP_STREX + cpu_exclusive_{test, info}
  linux-user: remove handling of aarch64's EXCP_STREX
  linux-user: remove handling of ARM's EXCP_STREX
  target-arm: emulate aarch64's LL/SC using cmpxchg helpers
  target-arm: emulate SWP with atomic_xchg helper
  target-arm: emulate LL/SC using cmpxchg helpers
  target-arm: Rearrange aa32 load and store functions
  tests: add atomic_add-bench
  target-i386: remove helper_lock()
  target-i386: emulate XCHG using atomic helper
  target-i386: emulate LOCK'ed BTX ops using atomic helpers
  target-i386: emulate LOCK'ed XADD using atomic helper
  target-i386: emulate LOCK'ed NEG using cmpxchg helper
  target-i386: emulate LOCK'ed NOT using atomic helper
  target-i386: emulate LOCK'ed INC using atomic helper
  target-i386: emulate LOCK'ed OP instructions using atomic helpers
  target-i386: emulate LOCK'ed cmpxchg using cmpxchg helpers
  tcg: Emit barriers with parallel_cpus
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-10-27 14:06:34 +01:00
Peter Maydell
8f9d84df97 -----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
 
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Merge remote-tracking branch 'remotes/jasowang/tags/net-pull-request' into staging

# gpg: Signature made Wed 26 Oct 2016 03:19:06 BST
# gpg:                using RSA key 0xEF04965B398D6211
# gpg: Good signature from "Jason Wang (Jason Wang on RedHat) <jasowang@redhat.com>"
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 215D 46F4 8246 689E C77F  3562 EF04 965B 398D 6211

* remotes/jasowang/tags/net-pull-request:
  colo-proxy: fix memory leak
  net: rtl8139: limit processing of ring descriptors
  net: vmxnet: initialise local tx descriptor
  e1000e: Don't zero out buffer address in rx descriptor
  net: rocker: set limit to DMA buffer size
  net: eepro100: fix memory leak in device uninit
  tap-bsd: OpenBSD uses tap(4) now
  net: pcnet: fix source formatting and indentation
  net: pcnet: check rx/tx descriptor ring length

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-10-27 12:45:45 +01:00
Peter Maydell
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Merge remote-tracking branch 'remotes/vivier/tags/m68k-part1-pull-request' into staging

# gpg: Signature made Tue 25 Oct 2016 19:58:46 BST
# gpg:                using RSA key 0xF30C38BD3F2FBE3C
# gpg: Good signature from "Laurent Vivier <lvivier@redhat.com>"
# gpg:                 aka "Laurent Vivier <laurent@vivier.eu>"
# gpg:                 aka "Laurent Vivier (Red Hat) <lvivier@redhat.com>"
# Primary key fingerprint: CD2F 75DD C8E3 A4DC 2E4F  5173 F30C 38BD 3F2F BE3C

* remotes/vivier/tags/m68k-part1-pull-request: (23 commits)
  target-m68k: Optimize gen_flush_flags
  target-m68k: Optimize some comparisons
  target-m68k: Use setcond for scc
  target-m68k: Introduce DisasCompare
  target-m68k: Reorg flags handling
  target-m68k: Remove incorrect clearing of cc_x
  target-m68k: Some fixes to SR and flags management
  target-m68k: Print flags properly
  target-m68k: update CPU flags management
  target-m68k: don't update cc_dest in helpers
  target-m68k: update move to/from ccr/sr
  target-m68k: remove m68k_cpu_exec_enter() and m68k_cpu_exec_exit()
  target-m68k: Replace helper_xflag_lt with setcond
  target-m68k: allow to update flags with operation on words and bytes
  target-m68k: REG() macro cleanup
  target-m68k: set PAGE_BITS to 12 for m68k
  target-m68k: define operand sizes
  target-m68k: set disassembler mode to 680x0 or coldfire
  target-m68k: introduce read_imXX() functions
  target-m68k: manage scaled index
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-10-27 11:58:43 +01:00
Richard Henderson
ed2839166c target-alpha: Emulate LL/SC using cmpxchg helpers
Emulating LL/SC with cmpxchg is not correct, since it can
suffer from the ABA problem.  However, portable parallel
code is written assuming only cmpxchg which means that in
practice this is a viable alternative.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:02 -07:00
Richard Henderson
6a73ecf5cf target-alpha: Introduce MMU_PHYS_IDX
Rather than using helpers for physical accesses, use a mmu index.
The primary cleanup is with store-conditional on physical addresses.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:02 -07:00
Emilio G. Cota
05188cc72f target-arm: remove EXCP_STREX + cpu_exclusive_{test, info}
The exception is not emitted anymore; remove it and the associated
TCG variables.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <1467054136-10430-31-git-send-email-cota@braap.org>
2016-10-26 08:29:02 -07:00
Emilio G. Cota
f4e6eb7ffe linux-user: remove handling of aarch64's EXCP_STREX
The exception is not emitted anymore.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <1467054136-10430-30-git-send-email-cota@braap.org>
2016-10-26 08:29:02 -07:00
Emilio G. Cota
b50b82fc48 linux-user: remove handling of ARM's EXCP_STREX
The exception is not emitted anymore.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twidle.net>
Message-Id: <1467054136-10430-29-git-send-email-cota@braap.org>
2016-10-26 08:29:02 -07:00
Emilio G. Cota
1dd089d0ee target-arm: emulate aarch64's LL/SC using cmpxchg helpers
Emulating LL/SC with cmpxchg is not correct, since it can
suffer from the ABA problem. Portable parallel code, however,
is written assuming only cmpxchg--and not LL/SC--is available.
This means that in practice emulating LL/SC with cmpxchg is
a viable alternative.

The appended emulates LL/SC pairs in aarch64 with cmpxchg helpers.
This works in both user and system mode. In usermode, it avoids
pausing all other CPUs to perform the LL/SC pair. The subsequent
performance and scalability improvement is significant, as the
plots below show. They plot the throughput of atomic_add-bench
compiled for ARM and executed on a 64-core x86 machine.

Hi-res plots: http://imgur.com/a/JVc8Y

                atomic_add-bench: 1000000 ops/thread, [0,1] range

  18 ++---------+----------+---------+----------+----------+----------+---++
     +cmpxchg +-E--+       +         +          +          +          +    |
  16 ++master +-H--+                                                      ++
     ||                                                                    |
  14 ++                                                                   ++
     | |                                                                   |
  12 ++|                                                                  ++
     | |                                                                   |
  10 ++++                                                                 ++
   8 ++E                                                                  ++
     |+++                                                                  |
   6 ++ |                                                                 ++
     |  |                                                                  |
   4 ++ |                                                                 ++
     |   |                                                                 |
   2 +H++E+---                                                            ++
     + |     +E++----+E+---+--+E+----++E+------+E+------+E++----+E+---+--+E|
   0 ++H-H----H-+-----H----+---------+----------+----------+----------+---++
     0          10         20        30         40         50         60
                                Number of threads

                atomic_add-bench: 1000000 ops/thread, [0,2] range

  18 ++---------+----------+---------+----------+----------+----------+---++
     +cmpxchg +-E--+       +         +          +          +          +    |
  16 ++master +-H--+                                                      ++
     | |                                                                   |
  14 ++E                                                                  ++
     | |                                                                   |
  12 ++|                                                                  ++
     |+++                                                                  |
  10 ++ |                                                                 ++
   8 ++ |                                                                 ++
     |  |                                                                  |
   6 ++ |                                                                 ++
     |   |                                                                 |
   4 ++  |                                                                ++
     |  +E+---                                                             |
   2 +H+     +E+-----+++              +++      +++   ---+E+-----+E+------+++
     +++        +    +E+---+--+E+----++E+------+E+---   ++++    +++   +  +E|
   0 ++H-H----H-+-----H----+---------+----------+----------+----------+---++
     0          10         20        30         40         50         60
                                Number of threads

               atomic_add-bench: 1000000 ops/thread, [0,128] range

  70 ++---------+----------+---------+----------+----------+----------+---++
     +cmpxchg +-E--+       +         +          +          +          +    |
  60 ++master +-H--+                  +++            ---+E+-----+E+------+E+
     |                        +E+------E-------+E+---                      |
     |                     ---        +++                                  |
  50 ++              +++---                                               ++
     |              -+E+                                                   |
  40 ++      +++----                                                      ++
     |        E-                                                           |
     |      --|                                                            |
  30 ++   -- +++                                                          ++
     |  +E+                                                                |
  20 ++E+                                                                 ++
     |E+                                                                   |
     |                                                                     |
  10 ++                                                                   ++
     +          +          +         +          +          +          +    |
   0 +HH-H----H-+-----H----+---------+----------+----------+----------+---++
     0          10         20        30         40         50         60
                                Number of threads

              atomic_add-bench: 1000000 ops/thread, [0,1024] range

  160 ++---------+---------+----------+---------+----------+----------+---++
      +cmpxchg +-E--+      +          +         +          +          +    |
  140 ++master +-H--+                                           +++      +++
      |                                                -+E+-----+E+-------E|
  120 ++                                       +++ ----                  +++
      |                                +++  ----E--                        |
  100 ++                              --E---   +++                        ++
      |                       +++ ---- +++                                 |
   80 ++                     --E--                                        ++
      |                  ---- +++                                          |
      |              -+E+                                                  |
   60 ++         ---- +++                                                 ++
      |      +E+-                                                          |
   40 ++   --                                                             ++
      |  +E+                                                               |
   20 +EE+                                                                ++
      +++        +         +          +         +          +          +    |
    0 +HH-H---H--+-----H---+----------+---------+----------+----------+---++
      0          10        20         30        40         50         60
                                Number of threads

[rth: Rearrange 128-bit cmpxchg helper.  Enforce alignment on LL.]

Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1467054136-10430-28-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:02 -07:00
Emilio G. Cota
cf12bce088 target-arm: emulate SWP with atomic_xchg helper
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1467054136-10430-25-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:02 -07:00
Emilio G. Cota
354161b37c target-arm: emulate LL/SC using cmpxchg helpers
Emulating LL/SC with cmpxchg is not correct, since it can
suffer from the ABA problem. Portable parallel code, however,
is written assuming only cmpxchg--and not LL/SC--is available.
This means that in practice emulating LL/SC with cmpxchg is
a viable alternative.

The appended emulates LL/SC pairs in ARM with cmpxchg helpers.
This works in both user and system mode. In usermode, it avoids
pausing all other CPUs to perform the LL/SC pair. The subsequent
performance and scalability improvement is significant, as the
plots below show. They plot the throughput of atomic_add-bench
compiled for ARM and executed on a 64-core x86 machine.

Hi-res plots: http://imgur.com/a/aNQpB

               atomic_add-bench: 1000000 ops/thread, [0,1] range

  9 ++---------+----------+----------+----------+----------+----------+---++
    +cmpxchg +-E--+       +          +          +          +          +    |
  8 +Emaster +-H--+                                                       ++
    | |                                                                    |
  7 ++E                                                                   ++
    | |                                                                    |
  6 ++++                                                                  ++
    |  |                                                                   |
  5 ++ |                                                                  ++
  4 ++ |                                                                  ++
    |  |                                                                   |
  3 ++ |                                                                  ++
    |   |                                                                  |
  2 ++  |                                                                 ++
    |H++E+---                                  +++  ---+E+------+E+------+E|
  1 +++     +E+-----+E+------+E+------+E+------+E+--   +++      +++       ++
    ++H+       +    +++   +  +++     ++++       +          +          +    |
  0 ++--H----H-+-----H----+----------+----------+----------+----------+---++
    0          10         20         30         40         50         60
                               Number of threads

                atomic_add-bench: 1000000 ops/thread, [0,2] range

  16 ++---------+----------+---------+----------+----------+----------+---++
     +cmpxchg +-E--+       +         +          +          +          +    |
  14 ++master +-H--+                                                      ++
     | |                                                                   |
  12 ++|                                                                  ++
     | E                                                                   |
  10 ++|                                                                  ++
     | |                                                                   |
   8 ++++                                                                 ++
     |E+|                                                                  |
     |  |                                                                  |
   6 ++ |                                                                 ++
     |   |                                                                 |
   4 ++  |                                                                ++
     |  +E+---       +++      +++              +++           ---+E+------+E|
   2 +H+     +E+------E-------+E+-----+E+------+E+------+E+--            +++
     + |        +    +++   +         ++++       +          +          +    |
   0 ++H-H----H-+-----H----+---------+----------+----------+----------+---++
     0          10         20        30         40         50         60
                                Number of threads

               atomic_add-bench: 1000000 ops/thread, [0,128] range

  70 ++---------+----------+---------+----------+----------+----------+---++
     +cmpxchg +-E--+       +         +          +       ++++          +    |
  60 ++master +-H--+                                 ----E------+E+-------++
     |                                        -+E+---   +++     +++      +E|
     |                                +++ ---- +++                       ++|
  50 ++                       +++  ---+E+-                                ++
     |                        -E---                                        |
  40 ++                    ---+++                                         ++
     |               +++---                                                |
     |              -+E+                                                   |
  30 ++      +++----                                                      ++
     |       +E+                                                           |
  20 ++ +++--                                                             ++
     |  +E+                                                                |
     |+E+                                                                  |
  10 +E+                                                                  ++
     +          +          +         +          +          +          +    |
   0 +HH-H----H-+-----H----+---------+----------+----------+----------+---++
     0          10         20        30         40         50         60
                                Number of threads

              atomic_add-bench: 1000000 ops/thread, [0,1024] range

  120 ++---------+---------+----------+---------+----------+----------+---++
      +cmpxchg +-E--+      +          +         +          +          +    |
      | master +-H--+                                                    ++|
  100 ++                                                              ----E+
      |                                                 +++  ---+E+---   ++|
      |                                                --E---   +++        |
   80 ++                                           ---- +++               ++
      |                                     ---+E+-                        |
   60 ++                              -+E+--                              ++
      |                       +++ ---- +++                                 |
      |                      -+E+-                                         |
   40 ++              +++----                                             ++
      |      +++   ---+E+                                                  |
      |     -+E+---                                                        |
   20 ++ +E+                                                              ++
      |+E+++                                                               |
      +E+        +         +          +         +          +          +    |
    0 +HH-H---H--+-----H---+----------+---------+----------+----------+---++
      0          10        20         30        40         50         60
                                Number of threads

[rth: Enforce alignment for ldrexd.]

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1467054136-10430-23-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:02 -07:00
Richard Henderson
7f5616f538 target-arm: Rearrange aa32 load and store functions
Stop specializing on TARGET_LONG_BITS == 32; unconditionally allocate
a temp and expand with tcg_gen_extu_i32_tl.  Split out gen_aa32_addr,
gen_aa32_frob64, gen_aa32_ld_i32 and gen_aa32_st_i32 as separate interfaces.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:02 -07:00
Emilio G. Cota
070e3edcea tests: add atomic_add-bench
With this microbenchmark we can measure the overhead of emulating atomic
instructions with a configurable degree of contention.

The benchmark spawns $n threads, each performing $o atomic ops (additions)
in a loop. Each atomic operation is performed on a different cache line
(assuming lines are 64b long) that is randomly selected from a range [0, $r).

[ Note: each $foo corresponds to a -foo flag ]

Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <1467054136-10430-20-git-send-email-cota@braap.org>
2016-10-26 08:29:01 -07:00
Emilio G. Cota
37b995f6e7 target-i386: remove helper_lock()
It's been superseded by the atomic helpers.

The use of the atomic helpers provides a significant performance and scalability
improvement. Below is the result of running the atomic_add-test microbenchmark with:
 $ x86_64-linux-user/qemu-x86_64 tests/atomic_add-bench -o 5000000 -r $r -n $n
, where $n is the number of threads and $r is the allowed range for the additions.

The scenarios measured are:
- atomic: implements x86' ADDL with the atomic_add helper (i.e. this patchset)
- cmpxchg: implement x86' ADDL with a TCG loop using the cmpxchg helper
- master: before this patchset

Results sorted in ascending range, i.e. descending degree of contention.
Y axis is Throughput in Mops/s. Tests are run on an AMD machine with 64
Opteron 6376 cores.

                atomic_add-bench: 5000000 ops/thread, [0,1] range

  25 ++---------+----------+---------+----------+----------+----------+---++
     + atomic +-E--+       +         +          +          +          +    |
     |cmpxchg +-H--+                                                       |
  20 +Emaster +-N--+                                                      ++
     ||                                                                    |
     |++                                                                   |
     ||                                                                    |
  15 +++                                                                  ++
     |N|                                                                   |
     |+|                                                                   |
  10 ++|                                                                  ++
     |+|+                                                                  |
     | |    -+E+------        +++  ---+E+------+E+------+E+-----+E+------+E|
     |+E+E+- +++     +E+------+E+--                                        |
   5 ++|+                                                                 ++
     |+N+H+---                                 +++                         |
     ++++N+--+H++----+++   +  +++  --++H+------+H+------+H++----+H+---+--- |
   0 ++---------+-----H----+---H-----+----------+----------+----------+---H+
     0          10         20        30         40         50         60
                                Number of threads

                atomic_add-bench: 5000000 ops/thread, [0,2] range

  25 ++---------+----------+---------+----------+----------+----------+---++
     ++atomic +-E--+       +         +          +          +          +    |
     |cmpxchg +-H--+                                                       |
  20 ++master +-N--+                                                      ++
     |E|                                                                   |
     |++                                                                   |
     ||E                                                                   |
  15 ++|                                                                  ++
     |N||                                                                  |
     |+||                                   ---+E+------+E+-----+E+------+E|
  10 ++| |        ---+E+------+E+-----+E+---                    +++      +++
     ||H+E+--+E+--                                                         |
     |+++++                                                                |
     | ||                                                                  |
   5 ++|+H+--                                  +++                        ++
     |+N+    -                              ---+H+------+H+------          |
     +  +N+--+H++----+H+---+--+H+----++H+---    +          +    +H+---+--+H|
   0 ++---------+----------+---------+----------+----------+----------+---++
     0          10         20        30         40         50         60
                                Number of threads

                atomic_add-bench: 5000000 ops/thread, [0,8] range

  40 ++---------+----------+---------+----------+----------+----------+---++
     ++atomic +-E--+       +         +          +          +          +    |
  35 +cmpxchg +-H--+                                                      ++
     | master +-N--+               ---+E+------+E+------+E+-----+E+------+E|
  30 ++|                   ---+E+--   +++                                 ++
     | |            -+E+---                                                |
  25 ++E        ---- +++                                                  ++
     |+++++ -+E+                                                           |
  20 +E+ E-- +++                                                          ++
     |H|+++                                                                |
     |+|                                       +H+-------                  |
  15 ++H+                                   ---+++      +H+------         ++
     |N++H+--                         +++---                    +H+------++|
  10 ++ +++  -       +++           ---+H+                       +++      +H+
     | |     +H+-----+H+------+H+--                                        |
   5 ++|                      +++                                         ++
     ++N+N+--+N++          +         +          +          +          +    |
   0 ++---------+----------+---------+----------+----------+----------+---++
     0          10         20        30         40         50         60
                                Number of threads

               atomic_add-bench: 5000000 ops/thread, [0,128] range

  160 ++---------+---------+----------+---------+----------+----------+---++
      + atomic +-E--+      +          +         +          +          +    |
  140 +cmpxchg +-H--+                          +++      +++               ++
      | master +-N--+                           E--------E------+E+------++|
  120 ++                                      --|        |      +++       E+
      |                                     -- +++      +++              ++|
  100 ++                                   -                              ++
      |                                +++-                     +++      ++|
   80 ++                              -+E+    -+H+------+H+------H--------++
      |                           ----    ----                  +++       H|
      |            ---+E+-----+E+-  ---+H+                               ++|
   60 ++     +E+---   +++  ---+H+---                                      ++
      |    --+++   ---+H+--                                                |
   40 ++ +E+-+H+---                                                       ++
      |  +H+                                                               |
   20 +EE+                                                                ++
      +N+        +         +          +         +          +          +    |
    0 ++N-N---N--+---------+----------+---------+----------+----------+---++
      0          10        20         30        40         50         60
                                Number of threads

              atomic_add-bench: 5000000 ops/thread, [0,1024] range

  350 ++---------+---------+----------+---------+----------+----------+---++
      + atomic +-E--+      +          +         +          +          +    |
  300 +cmpxchg +-H--+                                                    +++
      | master +-N--+                                           +++       ||
      |                                                 +++      |    ----E|
  250 ++                                                 |   ----E----    ++
      |                                              ----E---    |    ---+H|
  200 ++                                      -+E+---   +++  ---+H+---    ++
      |                                   ----         -+H+--              |
      |                                +E+     +++ ---- +++                |
  150 ++                            ---+++  ---+H+-                       ++
      |                          ---  -+H+--                               |
  100 ++                   ---+E+ ---- +++                                ++
      |      +++   ---+E+-----+H+-                                         |
      |     -+E+------+H+--                                                |
   50 ++ +E+                                                              ++
      +EE+       +         +          +         +          +          +    |
    0 ++N-N---N--+---------+----------+---------+----------+----------+---++
      0          10        20         30        40         50         60
                                Number of threads

  hi-res: http://imgur.com/a/fMRmq

For master I stopped measuring master after 8 threads, because there is little
point in measuring the well-known performance collapse of a contended lock.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1467054136-10430-21-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:01 -07:00
Emilio G. Cota
ea97ebe89f target-i386: emulate XCHG using atomic helper
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1467054136-10430-19-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:01 -07:00
Emilio G. Cota
cfe819d309 target-i386: emulate LOCK'ed BTX ops using atomic helpers
[rth: Avoid redundant qemu_ld in locked case.  Fix previously unnoticed
incorrect zero-extension of address in register-offset case.]

Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1467054136-10430-18-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:01 -07:00
Emilio G. Cota
f53b01817f target-i386: emulate LOCK'ed XADD using atomic helper
[rth: Move load of reg value to common location.]

Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1467054136-10430-17-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:01 -07:00
Emilio G. Cota
8eb8c73856 target-i386: emulate LOCK'ed NEG using cmpxchg helper
[rth: Move redundant qemu_load out of cmpxchg loop.]

Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1467054136-10430-16-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:01 -07:00
Emilio G. Cota
2a5fe8ae14 target-i386: emulate LOCK'ed NOT using atomic helper
[rth: Avoid qemu_load that's redundant with the atomic op.]

Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1467054136-10430-15-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:01 -07:00
Emilio G. Cota
60e573462f target-i386: emulate LOCK'ed INC using atomic helper
[rth: Merge gen_inc_locked back into gen_inc to share cc update.]

Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1467054136-10430-14-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:01 -07:00
Emilio G. Cota
a7cee522f3 target-i386: emulate LOCK'ed OP instructions using atomic helpers
[rth: Eliminate some unnecessary temporaries.]

Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1467054136-10430-13-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:01 -07:00
Emilio G. Cota
ae03f8de45 target-i386: emulate LOCK'ed cmpxchg using cmpxchg helpers
The diff here is uglier than necessary. All this does is to turn

FOO

into:

if (s->prefix & PREFIX_LOCK) {
  BAR
} else {
  FOO
}

where FOO is the original implementation of an unlocked cmpxchg.

[rth: Adjust unlocked cmpxchg to use movcond instead of branches.
Adjust helpers to use atomic helpers.]

Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1467054136-10430-6-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:01 -07:00
Richard Henderson
91682118aa tcg: Emit barriers with parallel_cpus
Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:01 -07:00
Richard Henderson
df79b996a7 tcg: Add CONFIG_ATOMIC64
Allow qemu to build on 32-bit hosts without 64-bit atomic ops.

Even if we only allow 32-bit hosts to multi-thread emulate 32-bit
guests, we still need some way to handle the 32-bit guest using a
64-bit atomic operation.  Do so by dropping back to single-step.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:01 -07:00
Richard Henderson
7ebee43ee3 tcg: Add atomic128 helpers
Force the use of cmpxchg16b on x86_64.

Wikipedia suggests that only very old AMD64 (circa 2004) did not have
this instruction.  Further, it's required by Windows 8 so no new cpus
will ever omit it.

If we truely care about these, then we could check this at startup time
and then avoid executing paths that use it.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:01 -07:00
Richard Henderson
c482cb117c tcg: Add atomic helpers
Add all of cmpxchg, op_fetch, fetch_op, and xchg.
Handle both endian-ness, and sizes up to 8.
Handle expanding non-atomically, when emulating in serial.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:01 -07:00
Richard Henderson
c86c6e4c80 cputlb: Tidy some macros
TGT_LE and TGT_BE are not size dependent and do not need to be
redefined.  The others are no longer used at all.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:00 -07:00
Richard Henderson
82a45b96a2 cputlb: Move most of iotlb code out of line
Saves 2k code size off of a cold path.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:00 -07:00
Richard Henderson
4097842885 cputlb: Remove includes from softmmu_template.h
We already include exec/address-spaces.h and exec/memory.h in
cputlb.c; the include of qemu/timer.h appears to be a fossil.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:00 -07:00
Richard Henderson
3b08f0a925 cputlb: Move probe_write out of softmmu_template.h
Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:00 -07:00
Richard Henderson
dea2198201 cputlb: Replace SHIFT with DATA_SIZE
Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:00 -07:00
Alex Bennée
b67cb68ba5 linux-user: enable parallel code generation on clone
The variable parallel_cpus controls the generation of thread aware
atomic code.  We only need to set it once we clone our first thread.
At this point any existing translations need to be thrown away.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:00 -07:00
Richard Henderson
fdbc2b5722 tcg: Add EXCP_ATOMIC
When we cannot emulate an atomic operation within a parallel
context, this exception allows us to stop the world and try
again in a serial context.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:00 -07:00
Richard Henderson
1edaeee095 int128: Add int128_make128
Allows Int128 to be used more generally, rather than having to
begin with 64-bit inputs and accumulate.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:00 -07:00
Richard Henderson
0846beb366 int128: Use __int128 if available
Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:00 -07:00
Richard Henderson
258dfaaad0 exec: Avoid direct references to Int128 parts
Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:29:00 -07:00
Richard Henderson
84bca3927b atomics: Add __nocheck atomic operations
While the check against sizeof(void *) is appropriate for
normal usage within qemu, there are places in which we want
wider operaions and have checked for their existance.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:28:57 -07:00
Emilio G. Cota
83d0c719f8 atomics: add atomic_op_fetch variants
This paves the way for upcoming work.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <1467054136-10430-9-git-send-email-cota@braap.org>
2016-10-26 08:28:57 -07:00
Emilio G. Cota
61696ddbdc atomics: add atomic_xor
This paves the way for upcoming work.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <1467054136-10430-8-git-send-email-cota@braap.org>
2016-10-26 08:28:56 -07:00
Richard Henderson
d1a9f2d12f atomics: Add parameters to macros
Making these functional rather than object macros will
prevent later problems with complex macro expansion.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-10-26 08:28:46 -07:00
Zhang Chen
2061c14c9b colo-proxy: fix memory leak
Fix memory leak in colo-compare.c and filter-rewriter.c
Report by Coverity and add some comments.

Signed-off-by: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
Reviewed-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2016-10-26 09:58:02 +08:00
Prasad J Pandit
c7c3591669 net: rtl8139: limit processing of ring descriptors
RTL8139 ethernet controller in C+ mode supports multiple
descriptor rings, each with maximum of 64 descriptors. While
processing transmit descriptor ring in 'rtl8139_cplus_transmit',
it does not limit the descriptor count and runs forever. Add
check to avoid it.

Reported-by: Andrew Henderson <hendersa@icculus.org>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2016-10-26 09:57:59 +08:00
Li Qiang
fdda170e50 net: vmxnet: initialise local tx descriptor
In Vmxnet3 device emulator while processing transmit(tx) queue,
when it reaches end of packet, it calls vmxnet3_complete_packet.
In that local 'txcq_descr' object is not initialised, which could
leak host memory bytes a guest.

Reported-by: Li Qiang <liqiang6-s@360.cn>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Reviewed-by: Dmitry Fleytman <dmitry@daynix.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2016-10-26 09:57:59 +08:00
Kevin Wolf
c89d416a2b e1000e: Don't zero out buffer address in rx descriptor
The e1000e emulation zeroes out any used rx descriptor and then writes a
completely newly constructed value there. By doing this, it doesn't only
update the write-back area of the descriptors (as it's supposed to do),
but it also clears the buffer address, which real hardware doesn't do.

The spec explicitly mentions in chapter 7.1.8 that it is valid for a
driver to reuse a descriptor and only update the status field while
doing so, i.e. reusing the old buffer address:

    If software statically allocates buffers, and uses memory read to
    check for completed descriptors, it simply has to zero the status
    byte in the descriptor to make it ready for reuse by hardware.

This patch fixes the behaviour to leave the buffer address in
descriptors unchanged even after the descriptor has been used.

Signed-off-by: Kevin Wolf <mail@kevin-wolf.de>
Reviewed-by: Dmitry Fleytman <dmitry@daynix.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2016-10-26 09:57:59 +08:00