qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: "Alex Bennée" <alex.bennee@linaro.org>
To: "Philippe Mathieu-Daudé" <f4bug@amsat.org>
Cc: Richard Henderson <richard.henderson@linaro.org>,
	qemu-devel@nongnu.org, robhenry@microsoft.com,
	mahmoudabdalghany@outlook.com, aaron@os.amperecomputing.com,
	cota@braap.org, kuhn.chenqun@huawei.com,
	Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH v2 16/21] accel/tcg: actually cache our partial icount TB
Date: Fri, 12 Feb 2021 17:06:24 +0000	[thread overview]
Message-ID: <87v9axxlbi.fsf@linaro.org> (raw)
In-Reply-To: <b80367a8-9596-8e83-d013-8f4eea66e9a4@amsat.org>


Philippe Mathieu-Daudé <f4bug@amsat.org> writes:

> On 2/11/21 7:48 PM, Richard Henderson wrote:
>> On 2/11/21 2:21 AM, Philippe Mathieu-Daudé wrote:
>>>> -    insns_left = MIN(0xffff, cpu->icount_budget);
>>>> +    insns_left = MIN(CF_COUNT_MASK, cpu->icount_budget);
>>>
>>> Can you describe this change a bit please?
>> 
>> Replacing a magic number with its proper symbol.
>
> I am confuse because I see:
>
> #define CF_COUNT_MASK  0x00007fff

This is the largest partial count you can store in the CF flags (0x8000
is used for LAST_IO). The decrement field can handle the full u16
although in practice I would never expect a final block to be more than
a few instructions. We could probably shorten the mask without any
deleterious effect if we needed to scrape together any more CFLAGS.

-- 
Alex Bennée


  reply	other threads:[~2021-02-12 17:12 UTC|newest]

Thread overview: 53+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-02-10 22:10 [PATCH v2 00/21] plugins/next pre-PR (hwprofile, regression fixes, icount count fix) Alex Bennée
2021-02-10 22:10 ` [PATCH v2 01/21] hw/virtio/pci: include vdev name in registered PCI sections Alex Bennée
2021-02-10 22:10 ` [PATCH v2 02/21] plugins: add API to return a name for a IO device Alex Bennée
2021-02-10 22:10 ` [PATCH v2 03/21] plugins: new hwprofile plugin Alex Bennée
2021-02-10 22:10 ` [PATCH v2 04/21] contrib: Don't use '#' flag of printf format Alex Bennée
2021-02-10 22:10 ` [PATCH v2 05/21] contrib: Fix some code style problems, ERROR: "foo * bar" should be "foo *bar" Alex Bennée
2021-02-10 22:10 ` [PATCH v2 06/21] contrib: Add spaces around operator Alex Bennée
2021-02-10 22:10 ` [PATCH v2 07/21] contrib: space required after that ',' Alex Bennée
2021-02-10 22:10 ` [PATCH v2 08/21] contrib: Open brace '{' following struct go on the same line Alex Bennée
2021-02-10 22:10 ` [PATCH v2 09/21] accel/tcg/plugin-gen: fix the call signature for inline callbacks Alex Bennée
2021-02-10 22:10 ` [PATCH v2 10/21] exec: Move TranslationBlock typedef to qemu/typedefs.h Alex Bennée
2021-02-11 10:14   ` Philippe Mathieu-Daudé
2021-02-11 10:24     ` Alex Bennée
2021-02-10 22:10 ` [PATCH v2 11/21] accel/tcg: Create io_recompile_replay_branch hook Alex Bennée
2021-02-11 10:12   ` Philippe Mathieu-Daudé
2021-02-10 22:10 ` [PATCH v2 12/21] target/mips: Create mips_io_recompile_replay_branch Alex Bennée
2021-02-11 10:10   ` Philippe Mathieu-Daudé
2021-02-10 22:10 ` [PATCH v2 13/21] target/sh4: Create superh_io_recompile_replay_branch Alex Bennée
2021-02-11 10:13   ` Philippe Mathieu-Daudé
2021-02-10 22:10 ` [PATCH v2 14/21] tests/plugin: expand insn test to detect duplicate instructions Alex Bennée
2021-02-10 22:10 ` [PATCH v2 15/21] tests/acceptance: add a new set of tests to exercise plugins Alex Bennée
2021-02-11 10:31   ` Philippe Mathieu-Daudé
2021-02-11 18:59     ` Wainer dos Santos Moschetta
2021-02-11 19:51   ` Wainer dos Santos Moschetta
2021-02-10 22:10 ` [PATCH v2 16/21] accel/tcg: actually cache our partial icount TB Alex Bennée
2021-02-11 10:21   ` Philippe Mathieu-Daudé
2021-02-11 18:48     ` Richard Henderson
2021-02-12 15:40       ` Philippe Mathieu-Daudé
2021-02-12 17:06         ` Alex Bennée [this message]
2021-02-11 18:48   ` Richard Henderson
2021-02-10 22:10 ` [PATCH v2 17/21] accel/tcg: cache single instruction TB on pending replay exception Alex Bennée
2021-02-11 19:12   ` Richard Henderson
2021-02-11 20:00     ` Alex Bennée
2021-02-10 22:10 ` [PATCH v2 18/21] accel/tcg: re-factor non-RAM execution code Alex Bennée
2021-02-11 19:19   ` Richard Henderson
2021-02-10 22:10 ` [PATCH v2 19/21] accel/tcg: remove CF_NOCACHE and special cases Alex Bennée
2021-02-10 22:10 ` [PATCH v2 20/21] accel/tcg: allow plugin instrumentation to be disable via cflags Alex Bennée
2021-02-12  0:53   ` Aaron Lindsay via
2021-02-12 11:22     ` Alex Bennée
2021-02-12 14:31       ` Aaron Lindsay via
2021-02-12 14:59         ` Alex Bennée
2021-02-12 14:43     ` Alex Bennée
2021-02-12 15:41       ` Aaron Lindsay via
2021-02-12 16:04         ` Alex Bennée
2021-02-12 16:50           ` Aaron Lindsay via
2021-02-12 17:19             ` Alex Bennée
2021-02-16 10:34             ` Alex Bennée
2021-02-17 16:32               ` Aaron Lindsay via
2021-02-12 16:00       ` Alex Bennée
2021-02-12 17:04         ` Aaron Lindsay via
2021-02-10 22:10 ` [PATCH v2 21/21] tests/acceptance: add a new tests to detect counting errors Alex Bennée
2021-02-11 10:24   ` Philippe Mathieu-Daudé
2021-02-11 19:56   ` Wainer dos Santos Moschetta

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=87v9axxlbi.fsf@linaro.org \
    --to=alex.bennee@linaro.org \
    --cc=aaron@os.amperecomputing.com \
    --cc=cota@braap.org \
    --cc=f4bug@amsat.org \
    --cc=kuhn.chenqun@huawei.com \
    --cc=mahmoudabdalghany@outlook.com \
    --cc=pbonzini@redhat.com \
    --cc=qemu-devel@nongnu.org \
    --cc=richard.henderson@linaro.org \
    --cc=robhenry@microsoft.com \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).