qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Kevin Wolf <kwolf@redhat.com>
To: Manos Pitsidianakis <el13635@mail.ntua.gr>,
	qemu-devel <qemu-devel@nongnu.org>,
	Stefan Hajnoczi <stefanha@redhat.com>,
	Alberto Garcia <berto@igalia.com>,
	qemu-block <qemu-block@nongnu.org>
Subject: Re: [Qemu-devel] [PATCH v3 5/7] block: add throttle block filter driver
Date: Thu, 3 Aug 2017 14:05:49 +0200	[thread overview]
Message-ID: <20170803120549.GH4456@dhcp-200-186.str.redhat.com> (raw)
In-Reply-To: <20170803114856.ardy4zn24yanjhlj@postretch>

[-- Attachment #1: Type: text/plain, Size: 9989 bytes --]

Am 03.08.2017 um 13:48 hat Manos Pitsidianakis geschrieben:
> On Thu, Aug 03, 2017 at 10:07:41AM +0200, Kevin Wolf wrote:
> > Am 31.07.2017 um 11:54 hat Manos Pitsidianakis geschrieben:
> > > +/* Extract ThrottleConfig options. Assumes cfg is initialized and will be
> > > + * checked for validity.
> > > + */
> > > +static int throttle_extract_options(QemuOpts *opts, ThrottleConfig *cfg,
> > > +                                     Error **errp)
> > > +{
> > > +    if (qemu_opt_get(opts, THROTTLE_OPT_PREFIX QEMU_OPT_BPS_TOTAL)) {
> > > +        cfg->buckets[THROTTLE_BPS_TOTAL].avg =
> > > +            qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX QEMU_OPT_BPS_TOTAL,
> > > +                                0);
> > > +    }
> > > +    if (qemu_opt_get(opts, THROTTLE_OPT_PREFIX QEMU_OPT_BPS_READ)) {
> > > +        cfg->buckets[THROTTLE_BPS_READ].avg  =
> > > +            qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX QEMU_OPT_BPS_READ,
> > > +                                0);
> > > +    }
> > > +    if (qemu_opt_get(opts, THROTTLE_OPT_PREFIX QEMU_OPT_BPS_WRITE)) {
> > > +        cfg->buckets[THROTTLE_BPS_WRITE].avg =
> > > +            qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX QEMU_OPT_BPS_WRITE,
> > > +                                0);
> > > +    }
> > > +    if (qemu_opt_get(opts, THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_TOTAL)) {
> > > +        cfg->buckets[THROTTLE_OPS_TOTAL].avg =
> > > +            qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_TOTAL,
> > > +                                0);
> > > +    }
> > > +    if (qemu_opt_get(opts, THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_READ)) {
> > > +        cfg->buckets[THROTTLE_OPS_READ].avg =
> > > +            qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_READ,
> > > +                                0);
> > > +    }
> > > +    if (qemu_opt_get(opts, THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_WRITE)) {
> > > +        cfg->buckets[THROTTLE_OPS_WRITE].avg =
> > > +            qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_WRITE,
> > > +                                0);
> > > +    }
> > > +    if (qemu_opt_get(opts, THROTTLE_OPT_PREFIX QEMU_OPT_BPS_TOTAL_MAX)) {
> > > +        cfg->buckets[THROTTLE_BPS_TOTAL].max =
> > > +            qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX
> > > +                                QEMU_OPT_BPS_TOTAL_MAX, 0);
> > > +    }
> > > +    if (qemu_opt_get(opts, THROTTLE_OPT_PREFIX QEMU_OPT_BPS_READ_MAX)) {
> > > +        cfg->buckets[THROTTLE_BPS_READ].max  =
> > > +            qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX
> > > +                                QEMU_OPT_BPS_READ_MAX, 0);
> > > +    }
> > > +    if (qemu_opt_get(opts, THROTTLE_OPT_PREFIX QEMU_OPT_BPS_WRITE_MAX)) {
> > > +        cfg->buckets[THROTTLE_BPS_WRITE].max =
> > > +            qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX
> > > +                                QEMU_OPT_BPS_WRITE_MAX, 0);
> > > +    }
> > > +    if (qemu_opt_get(opts, THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_TOTAL_MAX)) {
> > > +        cfg->buckets[THROTTLE_OPS_TOTAL].max =
> > > +            qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX
> > > +                                QEMU_OPT_IOPS_TOTAL_MAX, 0);
> > > +    }
> > > +    if (qemu_opt_get(opts, THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_READ_MAX)) {
> > > +        cfg->buckets[THROTTLE_OPS_READ].max =
> > > +            qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX
> > > +                                QEMU_OPT_IOPS_READ_MAX, 0);
> > > +    }
> > > +    if (qemu_opt_get(opts, THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_WRITE_MAX)) {
> > > +        cfg->buckets[THROTTLE_OPS_WRITE].max =
> > > +            qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX
> > > +                                QEMU_OPT_IOPS_WRITE_MAX, 0);
> > > +    }
> > > +    if (qemu_opt_get(opts, THROTTLE_OPT_PREFIX QEMU_OPT_BPS_TOTAL_MAX_LENGTH)) {
> > > +        if (qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX
> > > +                                QEMU_OPT_BPS_TOTAL_MAX_LENGTH, 1) > UINT_MAX) {
> > > +            error_setg(errp, "%s value must be in the range [0, %u]",
> > > +                       THROTTLE_OPT_PREFIX QEMU_OPT_BPS_TOTAL_MAX_LENGTH,
> > > +                       UINT_MAX);
> > > +            return -1;
> > > +        }
> > > +        cfg->buckets[THROTTLE_BPS_TOTAL].burst_length =
> > > +            qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX
> > > +                                QEMU_OPT_BPS_TOTAL_MAX_LENGTH, 1);
> > > +    }
> > > +    if (qemu_opt_get(opts, THROTTLE_OPT_PREFIX QEMU_OPT_BPS_READ_MAX_LENGTH)) {
> > > +        if (qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX
> > > +                                QEMU_OPT_BPS_READ_MAX_LENGTH, 1) > UINT_MAX) {
> > > +            error_setg(errp, "%s must be in the range [0, %u]",
> > > +                       THROTTLE_OPT_PREFIX QEMU_OPT_BPS_READ_MAX_LENGTH,
> > > +                       UINT_MAX);
> > > +            return -1;
> > > +        }
> > > +        cfg->buckets[THROTTLE_BPS_READ].burst_length  =
> > > +            qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX
> > > +                                QEMU_OPT_BPS_READ_MAX_LENGTH, 1);
> > > +    }
> > > +    if (qemu_opt_get(opts, THROTTLE_OPT_PREFIX QEMU_OPT_BPS_WRITE_MAX_LENGTH)) {
> > > +        if (qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX
> > > +                                QEMU_OPT_BPS_WRITE_MAX_LENGTH, 1) > UINT_MAX) {
> > > +            error_setg(errp, "%s must be in the range [0, %u]",
> > > +                       THROTTLE_OPT_PREFIX QEMU_OPT_BPS_WRITE_MAX_LENGTH,
> > > +                       UINT_MAX);
> > > +            return -1;
> > > +        }
> > > +        cfg->buckets[THROTTLE_BPS_WRITE].burst_length =
> > > +            qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX
> > > +                                QEMU_OPT_BPS_WRITE_MAX_LENGTH, 1);
> > > +    }
> > > +    if (qemu_opt_get(opts, THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_TOTAL_MAX_LENGTH)) {
> > > +        if (qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX
> > > +                                QEMU_OPT_IOPS_TOTAL_MAX_LENGTH, 1) > UINT_MAX) {
> > > +            error_setg(errp, "%s must be in the range [0, %u]",
> > > +                       THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_TOTAL_MAX_LENGTH,
> > > +                       UINT_MAX);
> > > +            return -1;
> > > +        }
> > > +        cfg->buckets[THROTTLE_OPS_TOTAL].burst_length =
> > > +            qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX
> > > +                                QEMU_OPT_IOPS_TOTAL_MAX_LENGTH, 1);
> > > +    }
> > > +    if (qemu_opt_get(opts, THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_READ_MAX_LENGTH)) {
> > > +        if (qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX
> > > +                                QEMU_OPT_IOPS_READ_MAX_LENGTH, 1) > UINT_MAX) {
> > > +            error_setg(errp, "%s must be in the range [0, %u]",
> > > +                       THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_READ_MAX_LENGTH,
> > > +                       UINT_MAX);
> > > +            return -1;
> > > +        }
> > > +        cfg->buckets[THROTTLE_OPS_READ].burst_length =
> > > +            qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX
> > > +                                QEMU_OPT_IOPS_READ_MAX_LENGTH, 1);
> > > +    }
> > > +    if (qemu_opt_get(opts, THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_WRITE_MAX_LENGTH)) {
> > > +        if (qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX
> > > +                                QEMU_OPT_IOPS_WRITE_MAX_LENGTH, 1) > UINT_MAX) {
> > > +            error_setg(errp, "%s must be in the range [0, %u]",
> > > +                       THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_WRITE_MAX_LENGTH,
> > > +                       UINT_MAX);
> > > +            return -1;
> > > +        }
> > > +        cfg->buckets[THROTTLE_OPS_WRITE].burst_length =
> > > +            qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX
> > > +                                QEMU_OPT_IOPS_WRITE_MAX_LENGTH, 1);
> > > +    }
> > > +    if (qemu_opt_get(opts, THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_SIZE)) {
> > > +        cfg->op_size =
> > > +            qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX QEMU_OPT_IOPS_SIZE,
> > > +                                0);
> > > +    }
> > > +    return 0;
> > > +}
> > 
> > This function is very repetitive, but each block is long enough that
> > you have to look closely to review whether the right constants are used
> > everywhere.
> > 
> > Maybe this could become a bit more readable with a macro or two?
> 
> How about this?
> 
> 
> #   #define IF_OPT_SET(rvalue,opt_name) \
> #       if (qemu_opt_get(opts, THROTTLE_OPT_PREFIX opt_name)) { \
> #           rvalue = qemu_opt_get_number(opts, THROTTLE_OPT_PREFIX opt_name,
> 0); }
> 
> #       IF_OPT_SET(cfg->buckets[THROTTLE_BPS_TOTAL].avg, QEMU_OPT_BPS_TOTAL);
> #       IF_OPT_SET(cfg->buckets[THROTTLE_BPS_READ].avg, QEMU_OPT_BPS_READ);
> [...]

Looks a lot more readable to me. :-)

If nobody objects, I'd suggest to go this way.

> > > +static int coroutine_fn throttle_co_pwritev(BlockDriverState *bs,
> > > +                                            uint64_t offset, uint64_t bytes,
> > > +                                            QEMUIOVector *qiov, int flags)
> > > +{
> > > +    ThrottleGroupMember *tgm = bs->opaque;
> > > +    throttle_group_co_io_limits_intercept(tgm, bytes, true);
> > > +
> > > +    return bdrv_co_preadv(bs->file, offset, bytes, qiov, flags);
> > > +}
> > 
> > I think we want to set BlockDriver.supported_write_flags so that passing
> > down flags is actually of any use.
> 
> Can you explain what you mean? Do you mean doing this in throttle_open():
> 
>    bs->supported_write_flags = bs->file->bs->supported_write_flags;
>    bs->supported_zero_flags = bs->file->bs->supported_zero_flags;

Yes, I think that should do the trick.

Kevin

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 801 bytes --]

  reply	other threads:[~2017-08-03 12:06 UTC|newest]

Thread overview: 43+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-07-31  9:54 [Qemu-devel] [PATCH v3 0/7] add throttle block driver filter Manos Pitsidianakis
2017-07-31  9:54 ` [Qemu-devel] [PATCH v3 1/7] block: move ThrottleGroup membership to ThrottleGroupMember Manos Pitsidianakis
2017-08-04 11:59   ` Alberto Garcia
2017-07-31  9:54 ` [Qemu-devel] [PATCH v3 2/7] block: add aio_context field in ThrottleGroupMember Manos Pitsidianakis
2017-08-04 12:14   ` Alberto Garcia
2017-07-31  9:54 ` [Qemu-devel] [PATCH v3 3/7] block: tidy ThrottleGroupMember initializations Manos Pitsidianakis
2017-08-04 12:35   ` Alberto Garcia
2017-07-31  9:54 ` [Qemu-devel] [PATCH v3 4/7] block: convert ThrottleGroup to object with QOM Manos Pitsidianakis
2017-08-01 15:47   ` Stefan Hajnoczi
2017-08-01 16:49     ` Manos Pitsidianakis
2017-08-02 10:39       ` Stefan Hajnoczi
2017-08-02 10:57         ` Manos Pitsidianakis
2017-08-02 14:43           ` Stefan Hajnoczi
2017-08-03  8:08           ` Kevin Wolf
2017-08-03 10:53             ` Stefan Hajnoczi
2017-08-03 11:17               ` Kevin Wolf
2017-08-03 12:29                 ` Manos Pitsidianakis
2017-08-08 13:01           ` Alberto Garcia
2017-07-31  9:54 ` [Qemu-devel] [PATCH v3 5/7] block: add throttle block filter driver Manos Pitsidianakis
2017-08-01 16:14   ` Stefan Hajnoczi
2017-08-03  8:07   ` Kevin Wolf
2017-08-03 11:48     ` Manos Pitsidianakis
2017-08-03 12:05       ` Kevin Wolf [this message]
2017-08-03 11:58     ` Eric Blake
2017-08-03 13:56       ` Manos Pitsidianakis
2017-08-08 13:13   ` Alberto Garcia
2017-08-08 13:45     ` Manos Pitsidianakis
2017-08-08 14:53       ` Alberto Garcia
2017-08-08 14:56         ` Manos Pitsidianakis
2017-08-08 15:04           ` Alberto Garcia
2017-08-09  9:36             ` Manos Pitsidianakis
2017-08-09 12:36               ` Alberto Garcia
2017-08-09 13:42                 ` Manos Pitsidianakis
2017-08-09 14:45                   ` Alberto Garcia
2017-08-09 15:39                     ` Kevin Wolf
2017-08-14 12:15                       ` Manos Pitsidianakis
2017-07-31  9:54 ` [Qemu-devel] [PATCH v3 6/7] block: add BlockDevOptionsThrottle to QAPI Manos Pitsidianakis
2017-08-01 16:16   ` Stefan Hajnoczi
2017-07-31  9:54 ` [Qemu-devel] [PATCH v3 7/7] block: add throttle block filter driver interface tests Manos Pitsidianakis
2017-08-03  8:07   ` Kevin Wolf
2017-08-03 13:24     ` Manos Pitsidianakis
2017-08-03 13:32       ` Kevin Wolf
2017-08-03 13:52         ` Manos Pitsidianakis

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=20170803120549.GH4456@dhcp-200-186.str.redhat.com \
    --to=kwolf@redhat.com \
    --cc=berto@igalia.com \
    --cc=el13635@mail.ntua.gr \
    --cc=qemu-block@nongnu.org \
    --cc=qemu-devel@nongnu.org \
    --cc=stefanha@redhat.com \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).