From: Peter Zijlstra <[email protected]>
To: Jens Axboe <[email protected]>
Cc: [email protected], [email protected],
[email protected], [email protected]
Subject: Re: [PATCH 1/7] futex: abstract out futex_op_to_flags() helper
Date: Wed, 12 Jul 2023 10:16:17 +0200 [thread overview]
Message-ID: <[email protected]> (raw)
In-Reply-To: <[email protected]>
On Tue, Jul 11, 2023 at 06:46:59PM -0600, Jens Axboe wrote:
> Rather than needing to duplicate this for the io_uring hook of futexes,
> abstract out a helper.
>
> No functional changes intended in this patch.
>
> Signed-off-by: Jens Axboe <[email protected]>
> ---
> kernel/futex/futex.h | 15 +++++++++++++++
> kernel/futex/syscalls.c | 11 ++---------
> 2 files changed, 17 insertions(+), 9 deletions(-)
>
> diff --git a/kernel/futex/futex.h b/kernel/futex/futex.h
> index b5379c0e6d6d..d2949fca37d1 100644
> --- a/kernel/futex/futex.h
> +++ b/kernel/futex/futex.h
> @@ -291,4 +291,19 @@ extern int futex_unlock_pi(u32 __user *uaddr, unsigned int flags);
>
> extern int futex_lock_pi(u32 __user *uaddr, unsigned int flags, ktime_t *time, int trylock);
>
> +static inline bool futex_op_to_flags(int op, int cmd, unsigned int *flags)
> +{
*flags = 0;
> + if (!(op & FUTEX_PRIVATE_FLAG))
> + *flags |= FLAGS_SHARED;
> +
> + if (op & FUTEX_CLOCK_REALTIME) {
> + *flags |= FLAGS_CLOCKRT;
> + if (cmd != FUTEX_WAIT_BITSET && cmd != FUTEX_WAIT_REQUEUE_PI &&
> + cmd != FUTEX_LOCK_PI2)
> + return false;
> + }
> +
> + return true;
> +}
> diff --git a/kernel/futex/syscalls.c b/kernel/futex/syscalls.c
> index a8074079b09e..75ca8c41cc94 100644
> --- a/kernel/futex/syscalls.c
> +++ b/kernel/futex/syscalls.c
> @@ -88,15 +88,8 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout,
> int cmd = op & FUTEX_CMD_MASK;
> unsigned int flags = 0;
and skip the initializer here.
>
> - if (!(op & FUTEX_PRIVATE_FLAG))
> - flags |= FLAGS_SHARED;
> -
> - if (op & FUTEX_CLOCK_REALTIME) {
> - flags |= FLAGS_CLOCKRT;
> - if (cmd != FUTEX_WAIT_BITSET && cmd != FUTEX_WAIT_REQUEUE_PI &&
> - cmd != FUTEX_LOCK_PI2)
> - return -ENOSYS;
> - }
> + if (!futex_op_to_flags(op, cmd, &flags))
> + return -ENOSYS;
>
then the helper is more self sufficient and doesn't rely on the caller
to initialize the flags word.
next prev parent reply other threads:[~2023-07-12 8:19 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-07-12 0:46 [PATCHSET 0/7] Add io_uring futex/futexv support Jens Axboe
2023-07-12 0:46 ` [PATCH 1/7] futex: abstract out futex_op_to_flags() helper Jens Axboe
2023-07-12 8:16 ` Peter Zijlstra [this message]
2023-07-12 14:59 ` Jens Axboe
2023-07-12 0:47 ` [PATCH 2/7] futex: factor out the futex wake handling Jens Axboe
2023-07-12 8:58 ` Peter Zijlstra
2023-07-12 15:02 ` Jens Axboe
2023-07-12 0:47 ` [PATCH 3/7] io_uring: add support for futex wake and wait Jens Axboe
2023-07-12 8:51 ` Peter Zijlstra
2023-07-12 15:05 ` Jens Axboe
2023-07-12 0:47 ` [PATCH 4/7] futex: add wake_data to struct futex_q Jens Axboe
2023-07-12 0:47 ` [PATCH 5/7] futex: make futex_parse_waitv() available as a helper Jens Axboe
2023-07-12 9:25 ` Peter Zijlstra
2023-07-12 15:06 ` Jens Axboe
2023-07-12 0:47 ` [PATCH 6/7] futex: make the vectored futex operations available Jens Axboe
2023-07-12 0:47 ` [PATCH 7/7] io_uring: add futex waitv Jens Axboe
2023-07-12 9:31 ` Peter Zijlstra
2023-07-12 15:10 ` Jens Axboe
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=20230712081617.GB3100107@hirez.programming.kicks-ass.net \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
/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