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* [Qemu-devel] [PATCH 00/13] target/ppc improve atomic operations
@ 2018-06-26 16:19 Richard Henderson
  2018-06-26 16:19 ` [Qemu-devel] [PATCH 01/13] target/ppc: Add do_unaligned_access hook Richard Henderson
                   ` (13 more replies)
  0 siblings, 14 replies; 23+ messages in thread
From: Richard Henderson @ 2018-06-26 16:19 UTC (permalink / raw)
  To: qemu-devel; +Cc: qemu-ppc, david

In another patch set this week, I had noticed the old linux-user
do_store_exclusive code was still present.  I had thought that was
dead code that simply hadn't been removed, but it turned out that
we had not completed the transition to tcg atomics for linux-user.

In the process, I discovered that we weren't using atomic operations
for the 128-bit lq, lqarx, and stqcx insns.  These would have simply
produced incorrect results for -smp in system mode.

I tidy the code a bit by making use of MO_ALIGN, which means that
we don't need a separate explicit alignment check.

I use the new min/max atomic operations I added recently for
ARMv8.2-Atomics and RISC-V.

Finally, Power9 has some *really* odd atomic operations in its
l[wd]at and st[wd]at instructions.  We were generating illegal
instruction for these.  I implement them for serial context and
force parallel context to grab the exclusive lock and try again.

Except for the trivial linux-user ll/sc case, I do not have any
code that exercises these instructions.  Perhaps the IBM folk
have something that can test the others?


r~


Richard Henderson (13):
  target/ppc: Add do_unaligned_access hook
  target/ppc: Use atomic load for LQ and LQARX
  target/ppc: Use atomic store for STQ
  target/ppc: Use atomic cmpxchg for STQCX
  target/ppc: Remove POWERPC_EXCP_STCX
  target/ppc: Tidy gen_conditional_store
  target/ppc: Split out gen_load_locked
  target/ppc: Split out gen_ld_atomic
  target/ppc: Split out gen_st_atomic
  target/ppc: Use MO_ALIGN for EXIWX and ECOWX
  target/ppc: Use atomic min/max helpers
  target/ppc: Implement the rest of gen_ld_atomic
  target/ppc: Implement the rest of gen_st_atomic

 target/ppc/cpu.h                |   8 +-
 target/ppc/helper.h             |  11 +
 target/ppc/internal.h           |   5 +
 linux-user/ppc/cpu_loop.c       | 123 ++----
 target/ppc/excp_helper.c        |  18 +-
 target/ppc/mem_helper.c         |  72 +++-
 target/ppc/translate.c          | 648 ++++++++++++++++++++------------
 target/ppc/translate_init.inc.c |   1 +
 8 files changed, 539 insertions(+), 347 deletions(-)

-- 
2.17.1

^ permalink raw reply	[flat|nested] 23+ messages in thread

end of thread, other threads:[~2018-06-29  4:15 UTC | newest]

Thread overview: 23+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2018-06-26 16:19 [Qemu-devel] [PATCH 00/13] target/ppc improve atomic operations Richard Henderson
2018-06-26 16:19 ` [Qemu-devel] [PATCH 01/13] target/ppc: Add do_unaligned_access hook Richard Henderson
2018-06-27  9:09   ` David Gibson
2018-06-27 13:52     ` Richard Henderson
2018-06-28  3:46       ` David Gibson
2018-06-26 16:19 ` [Qemu-devel] [PATCH 02/13] target/ppc: Use atomic load for LQ and LQARX Richard Henderson
2018-06-28  3:49   ` David Gibson
2018-06-28 15:22     ` Richard Henderson
2018-06-29  3:33       ` David Gibson
2018-06-26 16:19 ` [Qemu-devel] [PATCH 03/13] target/ppc: Use atomic store for STQ Richard Henderson
2018-06-28  3:51   ` David Gibson
2018-06-29  3:33   ` David Gibson
2018-06-26 16:19 ` [Qemu-devel] [PATCH 04/13] target/ppc: Use atomic cmpxchg for STQCX Richard Henderson
2018-06-26 16:19 ` [Qemu-devel] [PATCH 05/13] target/ppc: Remove POWERPC_EXCP_STCX Richard Henderson
2018-06-26 16:19 ` [Qemu-devel] [PATCH 06/13] target/ppc: Tidy gen_conditional_store Richard Henderson
2018-06-26 16:19 ` [Qemu-devel] [PATCH 07/13] target/ppc: Split out gen_load_locked Richard Henderson
2018-06-26 16:19 ` [Qemu-devel] [PATCH 08/13] target/ppc: Split out gen_ld_atomic Richard Henderson
2018-06-26 16:19 ` [Qemu-devel] [PATCH 09/13] target/ppc: Split out gen_st_atomic Richard Henderson
2018-06-26 16:19 ` [Qemu-devel] [PATCH 10/13] target/ppc: Use MO_ALIGN for EXIWX and ECOWX Richard Henderson
2018-06-26 16:19 ` [Qemu-devel] [PATCH 11/13] target/ppc: Use atomic min/max helpers Richard Henderson
2018-06-26 16:19 ` [Qemu-devel] [PATCH 12/13] target/ppc: Implement the rest of gen_ld_atomic Richard Henderson
2018-06-26 16:19 ` [Qemu-devel] [PATCH 13/13] target/ppc: Implement the rest of gen_st_atomic Richard Henderson
2018-06-29  4:15 ` [Qemu-devel] [PATCH 00/13] target/ppc improve atomic operations David Gibson

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