From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from phobos.denx.de (phobos.denx.de [IPv6:2a01:238:438b:c500:173d:9f52:ddab:ee01]) by sourceware.org (Postfix) with ESMTPS id 68535388881B for ; Mon, 21 Jun 2021 07:43:45 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 68535388881B Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=denx.de Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=denx.de Received: from ktm (85-222-111-42.dynamic.chello.pl [85.222.111.42]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: lukma@denx.de) by phobos.denx.de (Postfix) with ESMTPSA id 2E521829B9; Mon, 21 Jun 2021 09:43:44 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=denx.de; s=phobos-20191101; t=1624261424; bh=B8OZs+0SwXv0tcwnzelR9Qopu891IC0ygtBA7mKd6ic=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=FYFXsmXcWxOH+ycjTgEfN724lSDuoFEo8Snlx0pDEqLRCb/ZKLkmkuZ6QP7ELH4BX 2s9a5J1QGExSyGrSSLz2XNU5zeqfhiXasuIC1ZIfR8JQd0L/H5Qz5b3DyOCoIszPMq uM0zNhs2u09EMYVYXeSLd1AIQi9UZwf+Bz0IRgn6x5i6lv5u9D+SZ/hVI4sQepe4ao OH2/DA3bUpq3ph8YxczAOYP1md1T+iZiUtRiDM1BFMtJFUz2I7qG4LiBX7n3uswFVl 6j6m6omfUBJYXRMjy/fyAHs18fmoa7/6085zIPb5nsGnXsG4c2VLrZFJRVlpB0DDEF x9c29gh4sHTWA== Date: Mon, 21 Jun 2021 09:43:43 +0200 From: Lukasz Majewski To: Adhemerval Zanella Cc: libc-alpha@sourceware.org, Carlos O'Donell Subject: Re: [PATCH 09/18] linux: Remove time64-support Message-ID: <20210621094343.780e2373@ktm> In-Reply-To: <20210617115104.1359598-10-adhemerval.zanella@linaro.org> References: <20210617115104.1359598-1-adhemerval.zanella@linaro.org> <20210617115104.1359598-10-adhemerval.zanella@linaro.org> Organization: denx.de X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; boundary="Sig_/GV8orGszpHc9uee_k83r2kQ"; protocol="application/pgp-signature" X-Virus-Scanned: clamav-milter 0.103.2 at phobos.denx.de X-Virus-Status: Clean X-Spam-Status: No, score=-11.7 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, KAM_SHORT, RCVD_IN_BARRACUDACENTRAL, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 21 Jun 2021 07:43:47 -0000 --Sig_/GV8orGszpHc9uee_k83r2kQ Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Thu, 17 Jun 2021 08:50:55 -0300 Adhemerval Zanella wrote: > It breaks the usage case of live migration like CRIU or similar > and most usages can be optimized away by either building glibc with > a minimum 5.1 kernel or by using the 32-bit syscall for the common > case. >=20 > Checked on i686-linux-gnu on a 4.15 kernel and on a 5.11 kernel > (with and without --enable-kernel=3D5.1) and on x86_64-linux-gnu. > --- > sysdeps/unix/sysv/linux/Makefile | 2 +- > sysdeps/unix/sysv/linux/time64-support.c | 23 -------- > sysdeps/unix/sysv/linux/time64-support.h | 70 > ------------------------ 3 files changed, 1 insertion(+), 94 > deletions(-) delete mode 100644 > sysdeps/unix/sysv/linux/time64-support.c delete mode 100644 > sysdeps/unix/sysv/linux/time64-support.h >=20 > diff --git a/sysdeps/unix/sysv/linux/Makefile > b/sysdeps/unix/sysv/linux/Makefile index 710169a454..982755f980 100644 > --- a/sysdeps/unix/sysv/linux/Makefile > +++ b/sysdeps/unix/sysv/linux/Makefile > @@ -61,7 +61,7 @@ sysdep_routines +=3D adjtimex clone umount umount2 > readahead sysctl \ open_by_handle_at mlock2 pkey_mprotect pkey_set > pkey_get \ timerfd_gettime timerfd_settime prctl \ > process_vm_readv process_vm_writev clock_adjtime \ > - time64-support pselect32 select32 \ > + pselect32 select32 \ > xstat fxstat lxstat xstat64 fxstat64 lxstat64 \ > fxstatat fxstatat64 \ > xmknod xmknodat convert_scm_timestamps > diff --git a/sysdeps/unix/sysv/linux/time64-support.c > b/sysdeps/unix/sysv/linux/time64-support.c deleted file mode 100644 > index 0718e7421b..0000000000 > --- a/sysdeps/unix/sysv/linux/time64-support.c > +++ /dev/null > @@ -1,23 +0,0 @@ > -/* Auxiliary definitions for 64-bit time_t support. > - Copyright (C) 2020-2021 Free Software Foundation, Inc. > - This file is part of the GNU C Library. > - > - The GNU C Library is free software; you can redistribute it and/or > - modify it under the terms of the GNU Lesser General Public > - License as published by the Free Software Foundation; either > - version 2.1 of the License, or (at your option) any later version. > - > - The GNU C Library is distributed in the hope that it will be > useful, > - but WITHOUT ANY WARRANTY; without even the implied warranty of > - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > - Lesser General Public License for more details. > - > - You should have received a copy of the GNU Lesser General Public > - License along with the GNU C Library; if not, see > - . */ > - > -#include > - > -#ifndef __ASSUME_TIME64_SYSCALLS > -int __time64_support =3D 1; > -#endif > diff --git a/sysdeps/unix/sysv/linux/time64-support.h > b/sysdeps/unix/sysv/linux/time64-support.h deleted file mode 100644 > index 8466d37f8f..0000000000 > --- a/sysdeps/unix/sysv/linux/time64-support.h > +++ /dev/null > @@ -1,70 +0,0 @@ > -/* Auxiliary definitions for 64-bit time_t support. > - Copyright (C) 2020-2021 Free Software Foundation, Inc. > - This file is part of the GNU C Library. > - > - The GNU C Library is free software; you can redistribute it and/or > - modify it under the terms of the GNU Lesser General Public > - License as published by the Free Software Foundation; either > - version 2.1 of the License, or (at your option) any later version. > - > - The GNU C Library is distributed in the hope that it will be > useful, > - but WITHOUT ANY WARRANTY; without even the implied warranty of > - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > - Lesser General Public License for more details. > - > - You should have received a copy of the GNU Lesser General Public > - License along with the GNU C Library; if not, see > - . */ > - > -#include > -#include > - > -/* These helper functions are used to optimize the 64-bit time_t > support on > - configurations that requires support for 32-bit time_t fallback > - (!__ASSUME_TIME64_SYSCALLS). The idea is once the kernel > advertises that > - it does not have 64-bit time_t support, glibc will stop to try > issue the > - 64-bit time_t syscall altogether. > - > - For instance: > - > - #ifndef __NR_symbol_time64 > - # define __NR_symbol_time64 __NR_symbol > - #endif > - int r; > - if (supports_time64 ()) > - { > - r =3D INLINE_SYSCALL_CALL (symbol, ...); > - if (r =3D=3D 0 || errno !=3D ENOSYS) > - return r; > - > - mark_time64_unsupported (); > - } > - #ifndef __ASSUME_TIME64_SYSCALLS > - <32-bit fallback syscall> > - #endif > - return r; > - > - On configuration with default 64-bit time_t this optimization > should be > - optimized away by the compiler resulting in no overhead. */ > - > -#ifndef __ASSUME_TIME64_SYSCALLS > -extern int __time64_support attribute_hidden; > -#endif > - > -static inline bool > -supports_time64 (void) > -{ > -#ifdef __ASSUME_TIME64_SYSCALLS > - return true; > -#else > - return atomic_load_relaxed (&__time64_support) !=3D 0; > -#endif > -} > - > -static inline void > -mark_time64_unsupported (void) > -{ > -#ifndef __ASSUME_TIME64_SYSCALLS > - atomic_store_relaxed (&__time64_support, 0); > -#endif > -} Reviewed-by: Lukasz Majewski 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 --Sig_/GV8orGszpHc9uee_k83r2kQ Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- iQEzBAEBCgAdFiEEgAyFJ+N6uu6+XupJAR8vZIA0zr0FAmDQQy8ACgkQAR8vZIA0 zr3fhQf6AoxYry2ubheq3kbijtxOOkHCyOE+h4hSvRvMT+CbWO26VS3bgxjAPNKm 6KLDqL9UseL1zjAYE8QC9owLXHY3EzAkCJp9RfweuMWgwFeQcJaF28F6DfRzdZ6B ZLFgbcnEIyq5HMXbDGBIITf0SuFnC8CEt7SpRDSTSLj6O4FgrJ+6+ep6OrPhRHJR xXe0KQJAy4bcQ3swwwYLRUnKX5GESaN32B3MGJxuNd9O/bALxBtJDELQ3NI5M7uZ 5web173T0Aa+xcpSwdENC80v4+Ty2/k7mrJmy8QgTuz0BWnmKRJ6TYzTO0tNtvUQ zBYuAlBm5vEbLWjnVaPMGjJ5Rs8a8Q== =LmgI -----END PGP SIGNATURE----- --Sig_/GV8orGszpHc9uee_k83r2kQ--