From: Stefan Hajnoczi <stefanha@gmail.com>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: qemu-devel@nongnu.org, qemu-block@nongnu.org
Subject: Re: [Qemu-devel] [PATCH 02/10] qemu-thread: introduce QemuLockCnt
Date: Wed, 30 Nov 2016 13:05:08 +0000 [thread overview]
Message-ID: <20161130130508.GE2497@stefanha-x1.localdomain> (raw)
In-Reply-To: <20161129114707.2975-3-pbonzini@redhat.com>
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On Tue, Nov 29, 2016 at 12:46:59PM +0100, Paolo Bonzini wrote:
> A QemuLockCnt comprises a counter and a mutex, with primitives
> to increment and decrement the counter, and to take and release the
> mutex. It can be used to do lock-free visits to a data structure
> whenever mutexes would be too heavy-weight and the critical section
> is too long for RCU.
>
> This could be implemented simply by protecting the counter with the
> mutex, but QemuLockCnt is harder to misuse and more efficient.
>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
> docs/lockcnt.txt | 343 ++++++++++++++++++++++++++++++++++++++++++++++++++
> include/qemu/thread.h | 17 +++
> util/Makefile.objs | 1 +
> util/lockcnt.c | 113 +++++++++++++++++
> 4 files changed, 474 insertions(+)
> create mode 100644 docs/lockcnt.txt
> create mode 100644 util/lockcnt.c
>
> diff --git a/docs/lockcnt.txt b/docs/lockcnt.txt
> new file mode 100644
> index 0000000..fc5d240
> --- /dev/null
> +++ b/docs/lockcnt.txt
> @@ -0,0 +1,343 @@
> +DOCUMENTATION FOR LOCKED COUNTERS (aka QemuLockCnt)
> +===================================================
This file contains all the documentation but the header file has no doc
comments. Could you move everything into the header file (like
include/qom/object.h)?
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next prev parent reply other threads:[~2016-11-30 13:07 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-11-29 11:46 [Qemu-devel] [PATCH for-2.9 00/10] aio_context_acquire/release pushdown, part 1 Paolo Bonzini
2016-11-29 11:46 ` [Qemu-devel] [PATCH 01/10] aio: rename bh_lock to list_lock Paolo Bonzini
2016-11-30 12:53 ` Stefan Hajnoczi
2016-11-29 11:46 ` [Qemu-devel] [PATCH 02/10] qemu-thread: introduce QemuLockCnt Paolo Bonzini
2016-11-29 19:34 ` Eric Blake
2016-11-30 13:05 ` Stefan Hajnoczi [this message]
2017-02-02 19:06 ` Emilio G. Cota
2017-02-02 19:20 ` Emilio G. Cota
2016-11-29 11:47 ` [Qemu-devel] [PATCH 03/10] aio: make ctx->list_lock a QemuLockCnt, subsuming ctx->walking_bh Paolo Bonzini
2016-11-30 13:06 ` Stefan Hajnoczi
2016-11-29 11:47 ` [Qemu-devel] [PATCH 04/10] qemu-thread: optimize QemuLockCnt with futexes on Linux Paolo Bonzini
2016-11-30 13:19 ` Stefan Hajnoczi
2016-11-29 11:47 ` [Qemu-devel] [PATCH 05/10] aio: tweak walking in dispatch phase Paolo Bonzini
2016-11-30 13:38 ` Stefan Hajnoczi
2016-11-29 11:47 ` [Qemu-devel] [PATCH 06/10] aio-posix: remove walking_handlers, protecting AioHandler list with list_lock Paolo Bonzini
2016-11-30 13:31 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
2016-11-30 13:36 ` Paolo Bonzini
2016-12-01 15:32 ` [Qemu-devel] " Paolo Bonzini
2016-11-29 11:47 ` [Qemu-devel] [PATCH 07/10] aio-win32: " Paolo Bonzini
2016-11-30 13:34 ` Stefan Hajnoczi
2016-11-29 11:47 ` [Qemu-devel] [PATCH 08/10] aio: document locking Paolo Bonzini
2016-11-30 13:35 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
2016-11-29 11:47 ` [Qemu-devel] [PATCH 09/10] aio: push aio_context_acquire/release down to dispatching Paolo Bonzini
2016-11-30 13:37 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
2016-11-29 11:47 ` [Qemu-devel] [PATCH 10/10] async: optimize aio_bh_poll Paolo Bonzini
2016-11-30 13:38 ` [Qemu-devel] [Qemu-block] " Stefan Hajnoczi
-- strict thread matches above, loose matches on Subject: below --
2016-12-21 14:03 [Qemu-devel] [PATCH v2 00/10] aio_context_acquire/release pushdown, part 1 Paolo Bonzini
2016-12-21 14:03 ` [Qemu-devel] [PATCH 02/10] qemu-thread: introduce QemuLockCnt Paolo Bonzini
2017-01-04 13:26 [Qemu-devel] [PATCH v3 00/10] aio_context_acquire/release pushdown, part 1 Paolo Bonzini
2017-01-04 13:26 ` [Qemu-devel] [PATCH 02/10] qemu-thread: introduce QemuLockCnt Paolo Bonzini
2017-01-11 15:48 ` Fam Zheng
2017-01-11 16:09 ` Paolo Bonzini
2017-01-11 16:35 ` Stefan Hajnoczi
2017-01-11 16:51 ` Paolo Bonzini
2017-01-11 16:56 ` Stefan Hajnoczi
2017-01-12 16:55 [Qemu-devel] [PATCH v4 00/10] aio_context_acquire/release pushdown, part 1 Paolo Bonzini
2017-01-12 16:55 ` [Qemu-devel] [PATCH 02/10] qemu-thread: introduce QemuLockCnt Paolo Bonzini
2017-01-12 18:07 [Qemu-devel] [PATCH v5 00/10] aio_context_acquire/release pushdown, part 1 Paolo Bonzini
2017-01-12 18:07 ` [Qemu-devel] [PATCH 02/10] qemu-thread: introduce QemuLockCnt Paolo Bonzini
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