From: Palmer Dabbelt <palmer@rivosinc.com>
To: Arnd Bergmann <arnd@arndb.de>,
heiko@sntech.de, guoren@kernel.org, shorne@gmail.com
Cc: peterz@infradead.org, mingo@redhat.com,
Will Deacon <will@kernel.org>,
longman@redhat.com, boqun.feng@gmail.com, jonas@southpole.se,
stefan.kristiansson@saunalahti.fi,
Paul Walmsley <paul.walmsley@sifive.com>,
Palmer Dabbelt <palmer@dabbelt.com>,
aou@eecs.berkeley.edu, Arnd Bergmann <arnd@arndb.de>,
macro@orcam.me.uk, Greg KH <gregkh@linuxfoundation.org>,
sudipm.mukherjee@gmail.com, wangkefeng.wang@huawei.com,
jszhang@kernel.org, linux-csky@vger.kernel.org,
linux-kernel@vger.kernel.org, openrisc@lists.librecores.org,
linux-riscv@lists.infradead.org, linux-arch@vger.kernel.org,
Palmer Dabbelt <palmer@rivosinc.com>
Subject: [PATCH v3 3/7] asm-generic: qrwlock: Document the spinlock fairness requirements
Date: Thu, 14 Apr 2022 15:02:10 -0700 [thread overview]
Message-ID: <20220414220214.24556-4-palmer@rivosinc.com> (raw)
In-Reply-To: <20220414220214.24556-1-palmer@rivosinc.com>
From: Palmer Dabbelt <palmer@rivosinc.com>
I could only find the fairness requirements documented as the C code,
this calls them out in a comment just to be a bit more explicit.
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
include/asm-generic/qrwlock.h | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/include/asm-generic/qrwlock.h b/include/asm-generic/qrwlock.h
index 7ae0ece07b4e..24ae09c1db9f 100644
--- a/include/asm-generic/qrwlock.h
+++ b/include/asm-generic/qrwlock.h
@@ -2,6 +2,10 @@
/*
* Queue read/write lock
*
+ * These use generic atomic and locking routines, but depend on a fair spinlock
+ * implementation in order to be fair themselves. The implementation in
+ * asm-generic/spinlock.h meets these requirements.
+ *
* (C) Copyright 2013-2014 Hewlett-Packard Development Company, L.P.
*
* Authors: Waiman Long <waiman.long@hp.com>
--
2.34.1
next prev parent reply other threads:[~2022-04-14 22:05 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-04-14 22:02 [PATCH v3 0/7] Generic Ticket Spinlocks Palmer Dabbelt
2022-04-14 22:02 ` [PATCH v3 1/7] asm-generic: ticket-lock: New generic ticket-based spinlock Palmer Dabbelt
2022-04-15 1:09 ` Boqun Feng
2022-04-15 5:20 ` Palmer Dabbelt
2022-04-17 2:44 ` Boqun Feng
2022-04-15 1:27 ` Waiman Long
2022-04-15 16:46 ` Palmer Dabbelt
2022-04-15 17:02 ` Waiman Long
2022-04-14 22:02 ` [PATCH v3 2/7] asm-generic: qspinlock: Indicate the use of mixed-size atomics Palmer Dabbelt
2022-04-14 22:02 ` Palmer Dabbelt [this message]
2022-04-14 22:02 ` [PATCH v3 4/7] openrisc: Move to ticket-spinlock Palmer Dabbelt
2022-04-30 7:52 ` Stafford Horne
2022-04-14 22:02 ` [PATCH v3 5/7] RISC-V: Move to generic spinlocks Palmer Dabbelt
2022-04-14 22:02 ` [PATCH v3 6/7] RISC-V: Move to queued RW locks Palmer Dabbelt
2022-04-14 22:02 ` [PATCH v3 7/7] csky: Move to generic ticket-spinlock Palmer Dabbelt
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=20220414220214.24556-4-palmer@rivosinc.com \
--to=palmer@rivosinc.com \
--cc=aou@eecs.berkeley.edu \
--cc=arnd@arndb.de \
--cc=boqun.feng@gmail.com \
--cc=gregkh@linuxfoundation.org \
--cc=guoren@kernel.org \
--cc=heiko@sntech.de \
--cc=jonas@southpole.se \
--cc=jszhang@kernel.org \
--cc=linux-arch@vger.kernel.org \
--cc=linux-csky@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-riscv@lists.infradead.org \
--cc=longman@redhat.com \
--cc=macro@orcam.me.uk \
--cc=mingo@redhat.com \
--cc=openrisc@lists.librecores.org \
--cc=palmer@dabbelt.com \
--cc=paul.walmsley@sifive.com \
--cc=peterz@infradead.org \
--cc=shorne@gmail.com \
--cc=stefan.kristiansson@saunalahti.fi \
--cc=sudipm.mukherjee@gmail.com \
--cc=wangkefeng.wang@huawei.com \
--cc=will@kernel.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®