Hi Martin,
Thank you for your respond, I will modify it and resend
it later.
Regards,
Tang
发件人:
Martin Wilck
<mwilck@suse.com>
收件人:
tang.junhui@zte.com.cn,
christophe.varoqui@opensvc.com, hare@suse.de, bmarzins@redhat.com, bart.vanassche@sandisk.com,
抄送:
dm-devel@redhat.com,
zhang.kai16@zte.com.cn, tang.wenjun3@zte.com.cn
日期:
2016/12/29
04:26
主题:
Re: [PATCH 08/12]
libmultipath: wait one seconds for more uevents in uevent_listen() in uevents
burst situations
On Tue, 2016-12-27 at 16:03 +0800, tang.junhui@zte.com.cn
wrote:
> From: tang.junhui <tang.junhui@zte.com.cn>
>
> The more uevents are merged, the higher efficiency program will
> performs.
> So, do not process uevents after receiving immediately in uevents
> burst
> situations, but continue wait 1 seconds for more uevents except that
> too
> much uevents (2048) have already been received or too much time
> eclipse
> (60 seconds).
Hi Tang,
thanks for this impressive patch set. While I haven't had time to read
through the more complex parts yet, one small nitpick on this patch:
please use named constants rather than explicit numbers in the code.
Regards,
Martin
>
> Change-Id: I763d491540e8114a81d12d603281540a81502742
> Signed-off-by: tang.junhui <tang.junhui@zte.com.cn>
> ---
> libmultipath/uevent.c | 35 +++++++++++++++++++++++++++++++++--
> 1 file changed, 33 insertions(+), 2 deletions(-)
>
> diff --git a/libmultipath/uevent.c b/libmultipath/uevent.c
> index cc10d65..b0b05e9 100644
> --- a/libmultipath/uevent.c
> +++ b/libmultipath/uevent.c
> @@ -39,6 +39,7 @@
> #include <linux/netlink.h>
> #include <pthread.h>
> #include <sys/mman.h>
> +#include <sys/time.h>
> #include <libudev.h>
> #include <errno.h>
>
> @@ -490,11 +491,37 @@ struct uevent *uevent_from_udev_device(struct
> udev_device *dev)
>
return uev;
> }
>
> +bool uevent_burst(struct timeval *start_time, int events)
> +{
> +
struct timeval diff_time, end_time;
> +
unsigned long speed;
> +
unsigned long eclipse_ms;
> +
> +
gettimeofday(&end_time, NULL);
> +
timersub(&end_time, start_time, &diff_time);
> +
> +
eclipse_ms = diff_time.tv_sec * 1000 + diff_time.tv_usec /
> 1000;
> +
if (eclipse_ms == 0)
> +
return
true;
> +
/* max wait 60s */
> +
if (eclipse_ms > 60*1000) {
> +
condlog(1,
"burst continued =%lu ms, stoped",
> eclipse_ms);
> +
return
false;
> +
}
> +
> +
speed = (events * 1000) / eclipse_ms;
> +
if (speed > 10)
> +
return
true;
> +
> +
return false;
> +}
> +
> int uevent_listen(struct udev *udev)
> {
>
int err = 2;
>
struct udev_monitor *monitor = NULL;
>
int fd, socket_flags, events;
> +
struct timeval start_time;
>
int need_failback = 1;
>
int timeout = 30;
>
LIST_HEAD(uevlisten_tmp);
> @@ -548,6 +575,7 @@ int uevent_listen(struct udev *udev)
>
}
>
>
events = 0;
> +
gettimeofday(&start_time, NULL);
>
while (1) {
>
struct
uevent *uev;
>
struct
udev_device *dev;
> @@ -562,7 +590,8 @@ int uevent_listen(struct udev *udev)
>
errno
= 0;
>
fdcount
= poll(&ev_poll, 1, poll_timeout);
>
if
(fdcount && ev_poll.revents & POLLIN) {
> -
timeout = 0;
> +
timeout = uevent_burst(&start_time, events +
> 1) ? 1:0;
> +
>
dev = udev_monitor_receive_device(monitor);
>
if (!dev) {
>
condlog(0,
"failed getting udev
> device");
> @@ -578,7 +607,8 @@ int uevent_listen(struct udev *udev)
>
}
>
list_add_tail(&uev->node, &uevlisten_tmp);
>
events++;
> -
continue;
> +
if(events < 2048)
> +
continue;
>
}
>
if
(fdcount < 0) {
>
if (errno == EINTR)
> @@ -600,6 +630,7 @@ int uevent_listen(struct udev *udev)
>
pthread_mutex_unlock(uevq_lockp);
>
events = 0;
>
}
> +
gettimeofday(&start_time,
NULL);
>
timeout
= 30;
>
}
>
need_failback = 0;
--
Dr. Martin Wilck <mwilck@suse.com>, Tel. +49 (0)911 74053 2107
SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton
HRB 21284 (AG Nürnberg)