All of lore.kernel.org
 help / color / mirror / Atom feed
From: Nicholas Piggin <npiggin@gmail.com>
To: qemu-ppc@nongnu.org
Cc: Nicholas Piggin <npiggin@gmail.com>,
	qemu-devel@nongnu.org,
	Richard Henderson <richard.henderson@linaro.org>
Subject: [PATCH 2/4] tcg/ppc: ST_ST memory ordering is not provided with eieio
Date: Thu, 19 May 2022 23:59:06 +1000	[thread overview]
Message-ID: <20220519135908.21282-3-npiggin@gmail.com> (raw)
In-Reply-To: <20220519135908.21282-1-npiggin@gmail.com>

eieio does not provide ordering between stores to CI memory and stores
to cacheable memory so it can't be used as a general ST_ST barrier.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-of-by: Nicholas Piggin <npiggin@gmail.com>
---
 tcg/ppc/tcg-target.c.inc | 2 --
 1 file changed, 2 deletions(-)

diff --git a/tcg/ppc/tcg-target.c.inc b/tcg/ppc/tcg-target.c.inc
index cfcd121f9c..3ff845d063 100644
--- a/tcg/ppc/tcg-target.c.inc
+++ b/tcg/ppc/tcg-target.c.inc
@@ -1836,8 +1836,6 @@ static void tcg_out_mb(TCGContext *s, TCGArg a0)
     a0 &= TCG_MO_ALL;
     if (a0 == TCG_MO_LD_LD) {
         insn = LWSYNC;
-    } else if (a0 == TCG_MO_ST_ST) {
-        insn = EIEIO;
     }
     tcg_out32(s, insn);
 }
-- 
2.35.1



  parent reply	other threads:[~2022-05-19 14:06 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-05-19 13:59 [PATCH 0/4] ppc: improve some memory ordering issues Nicholas Piggin
2022-05-19 13:59 ` [PATCH 1/4] target/ppc: Fix eieio memory ordering semantics Nicholas Piggin
2022-05-19 15:30   ` Richard Henderson
2022-05-19 13:59 ` Nicholas Piggin [this message]
2022-05-19 13:59 ` [PATCH 3/4] tcg/ppc: Optimize memory ordering generation with lwsync Nicholas Piggin
2022-05-19 15:30   ` Richard Henderson
2022-05-19 13:59 ` [PATCH 4/4] target/ppc: Implement lwsync with weaker memory ordering Nicholas Piggin
2022-05-19 15:34   ` Richard Henderson
2022-05-23 19:24 ` [PATCH 0/4] ppc: improve some memory ordering issues Daniel Henrique Barboza

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20220519135908.21282-3-npiggin@gmail.com \
    --to=npiggin@gmail.com \
    --cc=qemu-devel@nongnu.org \
    --cc=qemu-ppc@nongnu.org \
    --cc=richard.henderson@linaro.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.