From: Paolo Bonzini <pbonzini@redhat.com>
To: Jamie Lokier <jamie@shareable.org>
Cc: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] [PATCH 11/19] use a bottom half to run timers
Date: Tue, 05 Jan 2010 09:38:58 +0100 [thread overview]
Message-ID: <4B42FAA2.3030403@redhat.com> (raw)
In-Reply-To: <20100104193819.GC13537@shareable.org>
On 01/04/2010 08:38 PM, Jamie Lokier wrote:
> In principle, if it does affect something, it seems likely there is
> already a buggy race condition. After all, if the timer and bottom
> half could trigger at the same time, which is the condition where the
> order is significant, then in principle the timer could have triggered
> slightly later because it depends on the host alarm behaviour.
No, the problem is when the timer function is _itself_ scheduling a
bottom half. Before my patch there was a guarantee that the bh would
run before TCG, now there is not. It can be fixed easily though.
Paolo
next prev parent reply other threads:[~2010-01-05 19:34 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-12-21 8:09 [Qemu-devel] [PATCH 00/19][RFC] Cleanups + split timer handling out of vl.o Paolo Bonzini
2009-12-21 8:09 ` [Qemu-devel] [PATCH 01/19] centralize handling of -icount Paolo Bonzini
2009-12-21 8:09 ` [Qemu-devel] [PATCH 02/19] add qemu_icount_round Paolo Bonzini
2009-12-21 8:09 ` [Qemu-devel] [PATCH 03/19] avoid dubiously clever code in win32_start_timer Paolo Bonzini
2010-01-04 19:34 ` Anthony Liguori
2010-01-04 18:39 ` Paolo Bonzini
2009-12-21 8:09 ` [Qemu-devel] [PATCH 04/19] fix error in win32_rearm_timer Paolo Bonzini
2009-12-21 8:09 ` [Qemu-devel] [PATCH 05/19] only one flag is needed for alarm_timer Paolo Bonzini
2009-12-21 8:09 ` [Qemu-devel] [PATCH 06/19] more alarm timer cleanup Paolo Bonzini
2009-12-21 8:09 ` [Qemu-devel] [PATCH 07/19] add qemu_get_clock_ns Paolo Bonzini
2009-12-21 8:09 ` [Qemu-devel] [PATCH 08/19] move kbd/mouse events to event.c Paolo Bonzini
2010-01-04 20:19 ` Anthony Liguori
2009-12-21 8:09 ` [Qemu-devel] [PATCH 09/19] remove qemu_rearm_alarm_timer from main loop Paolo Bonzini
2009-12-21 8:09 ` [Qemu-devel] [PATCH 10/19] add qemu_bh_scheduled Paolo Bonzini
2009-12-21 8:09 ` [Qemu-devel] [PATCH 11/19] use a bottom half to run timers Paolo Bonzini
2010-01-04 20:24 ` Anthony Liguori
2010-01-04 19:38 ` Jamie Lokier
2010-01-05 8:38 ` Paolo Bonzini [this message]
2010-01-04 20:01 ` [Qemu-devel] " Michael S. Tsirkin
2010-01-04 23:54 ` Anthony Liguori
2010-01-05 12:07 ` Michael S. Tsirkin
2010-01-05 15:23 ` malc
2010-01-05 15:23 ` Michael S. Tsirkin
2010-01-05 15:32 ` malc
2010-01-05 15:33 ` Michael S. Tsirkin
2010-01-05 15:39 ` malc
2010-01-04 20:01 ` Paolo Bonzini
2010-01-04 23:59 ` Anthony Liguori
2010-01-05 12:48 ` Paolo Bonzini
2010-01-05 13:06 ` Anthony Liguori
2010-01-06 1:20 ` Jamie Lokier
2009-12-21 8:09 ` [Qemu-devel] [PATCH 12/19] new function qemu_icount_delta Paolo Bonzini
2009-12-21 8:09 ` [Qemu-devel] [PATCH 13/19] move tcg_has_work to cpu-exec.c and rename it Paolo Bonzini
2009-12-21 8:09 ` [Qemu-devel] [PATCH 14/19] disentangle tcg and deadline calculation Paolo Bonzini
2009-12-21 8:09 ` [Qemu-devel] [PATCH 15/19] do not provide qemu_event_increment if iothread not used Paolo Bonzini
2009-12-21 8:09 ` [Qemu-devel] [PATCH 16/19] tweak qemu_notify_event Paolo Bonzini
2009-12-21 8:09 ` [Qemu-devel] [PATCH 17/19] move vmstate registration of vmstate_timers earlier Paolo Bonzini
2009-12-21 8:09 ` [Qemu-devel] [PATCH 18/19] introduce qemu_clock_enable Paolo Bonzini
2009-12-21 8:09 ` [Qemu-devel] [PATCH 19/19] split out qemu-timer.c Paolo Bonzini
2010-01-04 20:26 ` Anthony Liguori
2010-01-04 19:26 ` [Qemu-devel] [PATCH 00/19][RFC] Cleanups + split timer handling out of vl.o Anthony Liguori
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