All of lore.kernel.org
 help / color / mirror / Atom feed
From: Jan Kiszka <jan.kiszka@siemens.com>
To: Avi Kivity <avi@redhat.com>
Cc: kvm-devel <kvm@vger.kernel.org>
Subject: [PATCH] qemu-kvm: Drop polling property from qemu_cond_wait
Date: Tue, 28 Jul 2009 11:32:21 +0200	[thread overview]
Message-ID: <4A6EC5A5.8070009@siemens.com> (raw)
In-Reply-To: <4A6EC26A.4070306@redhat.com>

Avi Kivity wrote:
> On 07/28/2009 10:16 AM, Jan Kiszka wrote:
>> Hi,
>>
>> why do we wait on condition variables with silly timeouts (both in
>> upstream as in qemu-kvm)? There used to be some qemu_aio_poll in
>> qemu-kvm, but it's no longer there, and upstream never had (unless I
>> missed something). Is this polling legacy now? Remove it?
>>
>>    
> 
> Given that all uses are inside while loops, the timeouts are ignored. 
> It's completely pointless now.
> 

Then let's start with removing it from qemu-kvm:

------------>

No caller of qemu_cond_wait makes use of this polling anymore. Remove
it.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---

 qemu-kvm.c |    6 +-----
 1 files changed, 1 insertions(+), 5 deletions(-)

diff --git a/qemu-kvm.c b/qemu-kvm.c
index 32dce4a..0615d06 100644
--- a/qemu-kvm.c
+++ b/qemu-kvm.c
@@ -1557,12 +1557,8 @@ static inline unsigned long kvm_get_thread_id(void)
 static void qemu_cond_wait(pthread_cond_t *cond)
 {
     CPUState *env = cpu_single_env;
-    static const struct timespec ts = {
-        .tv_sec = 0,
-        .tv_nsec = 100000,
-    };
 
-    pthread_cond_timedwait(cond, &qemu_mutex, &ts);
+    pthread_cond_wait(cond, &qemu_mutex);
     cpu_single_env = env;
 }
 


  reply	other threads:[~2009-07-28  9:32 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-07-28  7:16 qemu_cond_wait polling Jan Kiszka
2009-07-28  7:16 ` [Qemu-devel] " Jan Kiszka
2009-07-28  9:18 ` Avi Kivity
2009-07-28  9:18   ` [Qemu-devel] " Avi Kivity
2009-07-28  9:32   ` Jan Kiszka [this message]
2009-08-03 11:59     ` [PATCH] qemu-kvm: Drop polling property from qemu_cond_wait Avi Kivity

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=4A6EC5A5.8070009@siemens.com \
    --to=jan.kiszka@siemens.com \
    --cc=avi@redhat.com \
    --cc=kvm@vger.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.