From: "Emilio G. Cota" <cota@braap.org>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: qemu-devel@nongnu.org, serge.fdrv@gmail.com,
alex.bennee@linaro.org, sergey.fedorov@linaro.org
Subject: Re: [Qemu-devel] [PATCH v7 00/16] cpu-exec: Safe work in quiescent state
Date: Wed, 21 Sep 2016 13:29:54 -0400 [thread overview]
Message-ID: <20160921172954.GG13385@flamenco> (raw)
In-Reply-To: <1474289459-15242-1-git-send-email-pbonzini@redhat.com>
On Mon, Sep 19, 2016 at 14:50:43 +0200, Paolo Bonzini wrote:
> In addition to fixing some of the issues found by Alex, safe work items
> need not run anymore with a mutex taken. Of course, cpu_exec_start/end
> and start_exclusive/end_exclusive are essentially the read and write
> side of a specialized rwlock, so there is still a lock in disguise looming
> to cause deadlocks; however, it does removes worries about recursive
> locking from CPU list manipulations.
>
> The new patches are 8, 12 and 13. Patch 12 of v6 has been split
> across patch 10 and patch 16.
I really like this patchset! Didn't have time to look at previous
iterations, but the use of the cpu_list_mutex to serialize safe
work is a great win--it simplifies things significantly.
BTW should we take this chance to RCU'ify the CPU list? This series
+ safe cpu_list traversals + cmpxchg changes = MTTCG user-mode would
be in very good shape. (full-system mode still needs work on the TLB
side, me thinks)
Thanks,
E.
next prev parent reply other threads:[~2016-09-21 17:30 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-19 12:50 [Qemu-devel] [PATCH v7 00/16] cpu-exec: Safe work in quiescent state Paolo Bonzini
2016-09-19 12:50 ` [Qemu-devel] [PATCH 01/16] cpus: pass CPUState to run_on_cpu helpers Paolo Bonzini
2016-09-19 12:50 ` [Qemu-devel] [PATCH 02/16] cpus: Move common code out of {async_, }run_on_cpu() Paolo Bonzini
2016-09-19 12:50 ` [Qemu-devel] [PATCH 03/16] cpus: Rename flush_queued_work() Paolo Bonzini
2016-09-19 12:50 ` [Qemu-devel] [PATCH 04/16] linux-user: Use QemuMutex and QemuCond Paolo Bonzini
2016-09-21 16:26 ` Emilio G. Cota
2016-09-21 16:32 ` Paolo Bonzini
2016-09-19 12:50 ` [Qemu-devel] [PATCH 05/16] linux-user: Add qemu_cpu_is_self() and qemu_cpu_kick() Paolo Bonzini
2016-09-19 12:50 ` [Qemu-devel] [PATCH 06/16] cpus-common: move CPU list management to common code Paolo Bonzini
2016-09-19 12:50 ` [Qemu-devel] [PATCH 07/16] cpus-common: move CPU work item " Paolo Bonzini
2016-09-21 17:03 ` Emilio G. Cota
2016-09-21 17:15 ` Paolo Bonzini
2016-09-19 12:50 ` [Qemu-devel] [PATCH 08/16] cpus-common: fix uninitialized variable use in run_on_cpu Paolo Bonzini
2016-09-19 12:50 ` [Qemu-devel] [PATCH 09/16] cpus-common: move exclusive work infrastructure from linux-user Paolo Bonzini
2016-09-19 12:50 ` [Qemu-devel] [PATCH 10/16] docs: include formal model for TCG exclusive sections Paolo Bonzini
2016-09-19 12:50 ` [Qemu-devel] [PATCH 11/16] cpus-common: always defer async_run_on_cpu work items Paolo Bonzini
2016-09-19 12:50 ` [Qemu-devel] [PATCH 12/16] cpus-common: remove redundant call to exclusive_idle() Paolo Bonzini
2016-09-19 12:50 ` [Qemu-devel] [PATCH 13/16] cpus-common: simplify locking for start_exclusive/end_exclusive Paolo Bonzini
2016-09-21 16:15 ` Emilio G. Cota
2016-09-21 16:20 ` Paolo Bonzini
2016-09-19 12:50 ` [Qemu-devel] [PATCH 14/16] cpus-common: Introduce async_safe_run_on_cpu() Paolo Bonzini
2016-09-21 16:08 ` Emilio G. Cota
2016-09-21 16:20 ` Paolo Bonzini
2016-09-19 12:50 ` [Qemu-devel] [PATCH 15/16] tcg: Make tb_flush() thread safe Paolo Bonzini
2016-09-21 16:05 ` Emilio G. Cota
2016-09-21 16:19 ` Paolo Bonzini
2016-09-21 17:37 ` Emilio G. Cota
2016-09-21 18:22 ` Paolo Bonzini
2016-09-19 12:50 ` [Qemu-devel] [PATCH 16/16] cpus-common: lock-free fast path for cpu_exec_start/end Paolo Bonzini
2016-09-21 17:24 ` Emilio G. Cota
2016-09-21 18:19 ` Paolo Bonzini
2016-09-21 22:14 ` Emilio G. Cota
2016-09-21 22:27 ` Emilio G. Cota
2016-09-22 8:46 ` Paolo Bonzini
2016-09-19 13:24 ` [Qemu-devel] [PATCH v7 00/16] cpu-exec: Safe work in quiescent state no-reply
2016-09-19 16:04 ` no-reply
2016-09-21 17:29 ` Emilio G. Cota [this message]
2016-09-21 18:20 ` Paolo Bonzini
-- strict thread matches above, loose matches on Subject: below --
2016-09-12 11:12 Paolo Bonzini
2016-09-14 17:16 ` Richard Henderson
2016-09-14 18:40 ` Paolo Bonzini
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