From: Lukasz Majewski <lukma@denx.de>
To: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Cc: libc-alpha@sourceware.org, Carlos O'Donell <carlos@redhat.com>
Subject: Re: [PATCH 04/18] linux: Only use 64-bit syscall if required for ppoll
Date: Mon, 21 Jun 2021 09:42:48 +0200 [thread overview]
Message-ID: <20210621094248.67e894cd@ktm> (raw)
In-Reply-To: <20210617115104.1359598-5-adhemerval.zanella@linaro.org>
[-- Attachment #1: Type: text/plain, Size: 5105 bytes --]
On Thu, 17 Jun 2021 08:50:50 -0300
Adhemerval Zanella <adhemerval.zanella@linaro.org> wrote:
> For !__ASSUME_TIME64_SYSCALLS there is no need to issue a 64-bit
> syscall if the provided timeout fits in a 32-bit one. The 64-bit
> usage should be rare since the timeout is a relative one. This also
> avoids the need to use supports_time64() (which breaks the usage case
> of live migration like CRIU or similar).
>
> Checked on i686-linux-gnu on a 4.15 kernel and on a 5.11 kernel
> (with and without --enable-kernel=5.1) and on x86_64-linux-gnu.
> ---
> sysdeps/unix/sysv/linux/Makefile | 9 +++++++
> sysdeps/unix/sysv/linux/ppoll.c | 41
> +++++++++++------------------ sysdeps/unix/sysv/linux/tst-ppoll.c |
> 15 +++++++++++ 3 files changed, 40 insertions(+), 25 deletions(-)
>
> diff --git a/sysdeps/unix/sysv/linux/Makefile
> b/sysdeps/unix/sysv/linux/Makefile index 294c366e3b..c36ea0e494 100644
> --- a/sysdeps/unix/sysv/linux/Makefile
> +++ b/sysdeps/unix/sysv/linux/Makefile
> @@ -137,6 +137,15 @@ tests-time64 += \
>
> CFLAGS-tst-sigcontext-get_pc.c = -fasynchronous-unwind-tables
>
> +ifeq (yes,$(build-shared))
> +librt = $(common-objpfx)rt/librt.so
> +else
> +librt = $(common-objpfx)rt/librt.a
> +endif
> +
> +$(objpfx)tst-ppoll: $(librt)
> +$(objpfx)tst-ppoll-time64: $(librt)
> +
> # Generate the list of SYS_* macros for the system calls (__NR_*
> # macros). The file syscall-names.list contains all possible system
> # call names, and the generated header file produces SYS_* macros for
> diff --git a/sysdeps/unix/sysv/linux/ppoll.c
> b/sysdeps/unix/sysv/linux/ppoll.c index 624f14f517..e1ad316e2e 100644
> --- a/sysdeps/unix/sysv/linux/ppoll.c
> +++ b/sysdeps/unix/sysv/linux/ppoll.c
> @@ -21,9 +21,6 @@
> #include <time.h>
> #include <sys/poll.h>
> #include <sysdep-cancel.h>
> -#include <kernel-features.h>
> -#include <time64-support.h>
> -
>
> int
> __ppoll64 (struct pollfd *fds, nfds_t nfds, const struct
> __timespec64 *timeout, @@ -38,40 +35,34 @@ __ppoll64 (struct pollfd
> *fds, nfds_t nfds, const struct __timespec64 *timeout, timeout =
> &tval; }
>
> - int ret;
> -
> - if (supports_time64 ())
> - {
> #ifndef __NR_ppoll_time64
> # define __NR_ppoll_time64 __NR_ppoll
> #endif
> +
> +#ifdef __ASSUME_TIME64_SYSCALLS
> + return SYSCALL_CANCEL (ppoll_time64, fds, nfds, timeout, sigmask,
> + __NSIG_BYTES);
> +#else
> + bool is32bit = timeout != NULL
> + ? in_time_t_range (timeout->tv_sec) : true;
> + int ret;
> + if (!is32bit)
> + {
> ret = SYSCALL_CANCEL (ppoll_time64, fds, nfds, timeout,
> sigmask, __NSIG_BYTES);
> -
> if (ret == 0 || errno != ENOSYS)
> return ret;
> -
> - mark_time64_unsupported ();
> + __set_errno (EOVERFLOW);
> + return -1;
> }
>
> -#ifndef __ASSUME_TIME64_SYSCALLS
> struct timespec ts32;
> - if (timeout)
> - {
> - if (! in_time_t_range (timeout->tv_sec))
> - {
> - __set_errno (EOVERFLOW);
> - return -1;
> - }
> -
> - ts32 = valid_timespec64_to_timespec (*timeout);
> - }
> + if (timeout != NULL)
> + ts32 = valid_timespec64_to_timespec (*timeout);
>
> - ret = SYSCALL_CANCEL (ppoll, fds, nfds, timeout ? &ts32 : NULL,
> sigmask,
> - __NSIG_BYTES);
> + return SYSCALL_CANCEL (ppoll, fds, nfds, timeout ? &ts32 : NULL,
> sigmask,
> + __NSIG_BYTES);
> #endif
> -
> - return ret;
> }
>
> #if __TIMESIZE != 64
> diff --git a/sysdeps/unix/sysv/linux/tst-ppoll.c
> b/sysdeps/unix/sysv/linux/tst-ppoll.c index 9fe6ad07ce..e21e2fcc72
> 100644 --- a/sysdeps/unix/sysv/linux/tst-ppoll.c
> +++ b/sysdeps/unix/sysv/linux/tst-ppoll.c
> @@ -19,9 +19,11 @@
> #include <time.h>
> #include <poll.h>
> #include <errno.h>
> +#include <intprops.h>
> #include <support/check.h>
> #include <support/xtime.h>
> #include <support/timespec.h>
> +#include <support/support.h>
> #include <stdbool.h>
>
> static int test_ppoll_timeout (bool zero_tmo)
> @@ -41,6 +43,16 @@ static int test_ppoll_timeout (bool zero_tmo)
> return 0;
> }
>
> +static void
> +test_ppoll_large_timeout (void)
> +{
> + support_create_timer (0, 100000000, false, NULL);
> + struct timespec ts = { TYPE_MAXIMUM (time_t), 0 };
> + struct pollfd fds = { -1, 0, 0 };
> + TEST_COMPARE (ppoll (&fds, 1, &ts, 0), -1);
> + TEST_VERIFY (errno == EINTR || errno == EOVERFLOW);
> +}
> +
> static int
> do_test (void)
> {
> @@ -50,6 +62,9 @@ do_test (void)
> /* Check if ppoll exits after specified timeout. */
> test_ppoll_timeout (false);
>
> + /* Check if ppoll with large timeout. */
> + test_ppoll_large_timeout ();
> +
> return 0;
> }
>
Reviewed-by: Lukasz Majewski <lukma@denx.de>
Best regards,
Lukasz Majewski
--
DENX Software Engineering GmbH, Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-59 Fax: (+49)-8142-66989-80 Email: lukma@denx.de
[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 488 bytes --]
next prev parent reply other threads:[~2021-06-21 7:42 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-17 11:50 [PATCH 00/18] More y2038 fixes Adhemerval Zanella
2021-06-17 11:50 ` [PATCH 01/18] Use 64 bit time_t stat internally Adhemerval Zanella
2021-06-21 7:42 ` Lukasz Majewski
2021-06-22 19:37 ` Florian Weimer
2021-06-22 19:51 ` Adhemerval Zanella
2021-06-17 11:50 ` [PATCH 02/18] Use LFS and 64 bit time for installed programs Adhemerval Zanella
2021-06-17 12:19 ` Andreas Schwab
2021-06-18 18:50 ` Adhemerval Zanella
2021-06-17 20:49 ` Joseph Myers
2021-06-18 18:14 ` Adhemerval Zanella
2021-06-17 11:50 ` [PATCH 03/18] support: Add support_create_timer Adhemerval Zanella
2021-06-21 7:42 ` Lukasz Majewski
2021-06-17 11:50 ` [PATCH 04/18] linux: Only use 64-bit syscall if required for ppoll Adhemerval Zanella
2021-06-21 7:42 ` Lukasz Majewski [this message]
2021-06-17 11:50 ` [PATCH 05/18] linux: Only use 64-bit syscall if required for pselect Adhemerval Zanella
2021-06-21 7:42 ` Lukasz Majewski
2021-06-17 11:50 ` [PATCH 06/18] linux: Only use 64-bit syscall if required for select Adhemerval Zanella
2021-06-21 7:43 ` Lukasz Majewski
2021-06-17 11:50 ` [PATCH 07/18] linux: Remove supports_time64 () from clock_getres Adhemerval Zanella
2021-06-21 7:43 ` Lukasz Majewski
2021-06-17 11:50 ` [PATCH 08/18] linux: Remove supports_time64 () from clock_gettime Adhemerval Zanella
2021-06-21 7:43 ` Lukasz Majewski
2021-06-17 11:50 ` [PATCH 09/18] linux: Remove time64-support Adhemerval Zanella
2021-06-21 7:43 ` Lukasz Majewski
2021-06-17 11:50 ` [PATCH 10/18] linux: timerfd_gettime minor cleanup Adhemerval Zanella
2021-06-21 7:43 ` Lukasz Majewski
2021-06-17 11:50 ` [PATCH 11/18] linux: Only use 64-bit syscall if required for semtimedop Adhemerval Zanella
2021-06-21 7:43 ` Lukasz Majewski
2021-06-17 11:50 ` [PATCH 12/18] linux: Only use 64-bit syscall if required for timerfd_settime Adhemerval Zanella
2021-06-21 7:44 ` Lukasz Majewski
2021-06-17 11:50 ` [PATCH 13/18] linux: Only use 64-bit syscall if required for mq_timedreceive Adhemerval Zanella
2021-06-21 7:44 ` Lukasz Majewski
2021-06-17 11:51 ` [PATCH 14/18] linux: Only use 64-bit syscall if required for mq_timedsend Adhemerval Zanella
2021-06-21 7:44 ` Lukasz Majewski
2021-06-17 11:51 ` [PATCH 15/18] linux: Only use 64-bit syscall if required for sigtimedwait Adhemerval Zanella
2021-06-17 12:25 ` Andreas Schwab
2021-06-22 14:58 ` Adhemerval Zanella
2021-06-17 11:51 ` [PATCH 16/18] linux: Only use 64-bit syscall if required for utimensat family Adhemerval Zanella
2021-06-21 7:45 ` Lukasz Majewski
2021-06-17 11:51 ` [PATCH 17/18] linux: Only use 64-bit syscall if required for internal futex Adhemerval Zanella
2021-06-21 7:45 ` Lukasz Majewski
2021-06-17 11:51 ` [PATCH 18/18] linux: Only use 64-bit syscall if required for clock_nanosleep Adhemerval Zanella
2021-06-17 15:11 ` Lukasz Majewski
2021-06-17 17:45 ` Adhemerval Zanella
2021-06-21 7:46 ` Lukasz Majewski
2021-06-17 14:20 ` [PATCH 00/18] More y2038 fixes Lukasz Majewski
2021-06-17 17:41 ` Adhemerval Zanella
2021-06-17 20:58 ` Joseph Myers
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=20210621094248.67e894cd@ktm \
--to=lukma@denx.de \
--cc=adhemerval.zanella@linaro.org \
--cc=carlos@redhat.com \
--cc=libc-alpha@sourceware.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 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 read-only IMAP folder(s) and NNTP newsgroup(s).