From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qk1-x741.google.com (mail-qk1-x741.google.com [IPv6:2607:f8b0:4864:20::741]) by sourceware.org (Postfix) with ESMTPS id C7C903857C5C for ; Fri, 16 Oct 2020 14:46:12 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org C7C903857C5C Received: by mail-qk1-x741.google.com with SMTP id a23so2074185qkg.13 for ; Fri, 16 Oct 2020 07:46:12 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:to:cc:references:from:autocrypt:subject :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=/ewNIF+ZPYVtkhUZ0m9U3P9V8haoAIR3e7u/UKGWyWE=; b=LCQPJ4TCLRJUWS2ohP5R5g2FZLyXDcmSlcyWHaLdsRxKpevoUI6VhgzHAcbuLtxcCO pBorjZt8k7M9XsRVsxc7DlieRdmgaaioiwfRBMVk7tJKR8mtS7FoXbyMm0snIpj+JVhQ +o1y2qfyOOoEbONku6eHJBbpkFAF60GkXzARFJhh1SvyHwPzXu6d1nDkfZAix//duHNg WAejhslCWx9zmVZpa2xfWNclqR5g+ZDPZO1OvW+GRcPk9PY12ubJ5CWeWA4PukMz6Av1 fxkjdGh8YtJOuOnaoXM3j1dNkcczpvYdfSrloYnNDfaxQu/+AyQZKnGYYDmsM05MTB6I IyEQ== X-Gm-Message-State: AOAM532sXOgG9E+WGkkuAqGkz4rwgM22z5qBKLT/Sas2pSLoy0BSyNzg VVQbOdTJnDJvLaJVzCkNmZF5gQ== X-Google-Smtp-Source: ABdhPJxkRDuSasnGfuXN3Q3ILQ2Svkw09qm+uagbBxb0/103tYL9H56AlTzsUd+MGuws2fVkDSpgbg== X-Received: by 2002:a05:620a:22d4:: with SMTP id o20mr4091278qki.151.1602859545052; Fri, 16 Oct 2020 07:45:45 -0700 (PDT) Received: from [192.168.1.4] ([177.194.48.209]) by smtp.googlemail.com with ESMTPSA id z37sm1081458qtz.67.2020.10.16.07.45.41 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 16 Oct 2020 07:45:44 -0700 (PDT) To: Lukasz Majewski , Joseph Myers , Paul Eggert Cc: Alistair Francis , Arnd Bergmann , Alistair Francis , GNU C Library , Florian Weimer , Carlos O'Donell , Stepan Golosunov , Andreas Schwab , Zack Weinberg References: <20201016133218.20864-1-lukma@denx.de> From: Adhemerval Zanella Autocrypt: addr=adhemerval.zanella@linaro.org; prefer-encrypt=mutual; keydata= mQINBFcVGkoBEADiQU2x/cBBmAVf5C2d1xgz6zCnlCefbqaflUBw4hB/bEME40QsrVzWZ5Nq 8kxkEczZzAOKkkvv4pRVLlLn/zDtFXhlcvQRJ3yFMGqzBjofucOrmdYkOGo0uCaoJKPT186L NWp53SACXguFJpnw4ODI64ziInzXQs/rUJqrFoVIlrPDmNv/LUv1OVPKz20ETjgfpg8MNwG6 iMizMefCl+RbtXbIEZ3TE/IaDT/jcOirjv96lBKrc/pAL0h/O71Kwbbp43fimW80GhjiaN2y WGByepnkAVP7FyNarhdDpJhoDmUk9yfwNuIuESaCQtfd3vgKKuo6grcKZ8bHy7IXX1XJj2X/ BgRVhVgMHAnDPFIkXtP+SiarkUaLjGzCz7XkUn4XAGDskBNfbizFqYUQCaL2FdbW3DeZqNIa nSzKAZK7Dm9+0VVSRZXP89w71Y7JUV56xL/PlOE+YKKFdEw+gQjQi0e+DZILAtFjJLoCrkEX w4LluMhYX/X8XP6/C3xW0yOZhvHYyn72sV4yJ1uyc/qz3OY32CRy+bwPzAMAkhdwcORA3JPb kPTlimhQqVgvca8m+MQ/JFZ6D+K7QPyvEv7bQ7M+IzFmTkOCwCJ3xqOD6GjX3aphk8Sr0dq3 4Awlf5xFDAG8dn8Uuutb7naGBd/fEv6t8dfkNyzj6yvc4jpVxwARAQABtElBZGhlbWVydmFs IFphbmVsbGEgTmV0dG8gKExpbmFybyBWUE4gS2V5KSA8YWRoZW1lcnZhbC56YW5lbGxhQGxp bmFyby5vcmc+iQI3BBMBCAAhBQJXFRpKAhsDBQsJCAcDBRUKCQgLBRYCAwEAAh4BAheAAAoJ EKqx7BSnlIjv0e8P/1YOYoNkvJ+AJcNUaM5a2SA9oAKjSJ/M/EN4Id5Ow41ZJS4lUA0apSXW NjQg3VeVc2RiHab2LIB4MxdJhaWTuzfLkYnBeoy4u6njYcaoSwf3g9dSsvsl3mhtuzm6aXFH /Qsauav77enJh99tI4T+58rp0EuLhDsQbnBic/ukYNv7sQV8dy9KxA54yLnYUFqH6pfH8Lly sTVAMyi5Fg5O5/hVV+Z0Kpr+ZocC1YFJkTsNLAW5EIYSP9ftniqaVsim7MNmodv/zqK0IyDB GLLH1kjhvb5+6ySGlWbMTomt/or/uvMgulz0bRS+LUyOmlfXDdT+t38VPKBBVwFMarNuREU2 69M3a3jdTfScboDd2ck1u7l+QbaGoHZQ8ZNUrzgObltjohiIsazqkgYDQzXIMrD9H19E+8fw kCNUlXxjEgH/Kg8DlpoYJXSJCX0fjMWfXywL6ZXc2xyG/hbl5hvsLNmqDpLpc1CfKcA0BkK+ k8R57fr91mTCppSwwKJYO9T+8J+o4ho/CJnK/jBy1pWKMYJPvvrpdBCWq3MfzVpXYdahRKHI ypk8m4QlRlbOXWJ3TDd/SKNfSSrWgwRSg7XCjSlR7PNzNFXTULLB34sZhjrN6Q8NQZsZnMNs TX8nlGOVrKolnQPjKCLwCyu8PhllU8OwbSMKskcD1PSkG6h3r0AquQINBFcVGkoBEACgAdbR Ck+fsfOVwT8zowMiL3l9a2DP3Eeak23ifdZG+8Avb/SImpv0UMSbRfnw/N81IWwlbjkjbGTu oT37iZHLRwYUFmA8fZX0wNDNKQUUTjN6XalJmvhdz9l71H3WnE0wneEM5ahu5V1L1utUWTyh VUwzX1lwJeV3vyrNgI1kYOaeuNVvq7npNR6t6XxEpqPsNc6O77I12XELic2+36YibyqlTJIQ V1SZEbIy26AbC2zH9WqaKyGyQnr/IPbTJ2Lv0dM3RaXoVf+CeK7gB2B+w1hZummD21c1Laua +VIMPCUQ+EM8W9EtX+0iJXxI+wsztLT6vltQcm+5Q7tY+HFUucizJkAOAz98YFucwKefbkTp eKvCfCwiM1bGatZEFFKIlvJ2QNMQNiUrqJBlW9nZp/k7pbG3oStOjvawD9ZbP9e0fnlWJIsj 6c7pX354Yi7kxIk/6gREidHLLqEb/otuwt1aoMPg97iUgDV5mlNef77lWE8vxmlY0FBWIXuZ yv0XYxf1WF6dRizwFFbxvUZzIJp3spAao7jLsQj1DbD2s5+S1BW09A0mI/1DjB6EhNN+4bDB SJCOv/ReK3tFJXuj/HbyDrOdoMt8aIFbe7YFLEExHpSk+HgN05Lg5TyTro8oW7TSMTk+8a5M kzaH4UGXTTBDP/g5cfL3RFPl79ubXwARAQABiQIfBBgBCAAJBQJXFRpKAhsMAAoJEKqx7BSn lIjvI/8P/jg0jl4Tbvg3B5kT6PxJOXHYu9OoyaHLcay6Cd+ZrOd1VQQCbOcgLFbf4Yr+rE9l mYsY67AUgq2QKmVVbn9pjvGsEaz8UmfDnz5epUhDxC6yRRvY4hreMXZhPZ1pbMa6A0a/WOSt AgFj5V6Z4dXGTM/lNManr0HjXxbUYv2WfbNt3/07Db9T+GZkpUotC6iknsTA4rJi6u2ls0W9 1UIvW4o01vb4nZRCj4rni0g6eWoQCGoVDk/xFfy7ZliR5B+3Z3EWRJcQskip/QAHjbLa3pml xAZ484fVxgeESOoaeC9TiBIp0NfH8akWOI0HpBCiBD5xaCTvR7ujUWMvhsX2n881r/hNlR9g fcE6q00qHSPAEgGr1bnFv74/1vbKtjeXLCcRKk3Ulw0bY1OoDxWQr86T2fZGJ/HIZuVVBf3+ gaYJF92GXFynHnea14nFFuFgOni0Mi1zDxYH/8yGGBXvo14KWd8JOW0NJPaCDFJkdS5hu0VY 7vJwKcyHJGxsCLU+Et0mryX8qZwqibJIzu7kUJQdQDljbRPDFd/xmGUFCQiQAncSilYOcxNU EMVCXPAQTteqkvA+gNqSaK1NM9tY0eQ4iJpo+aoX8HAcn4sZzt2pfUB9vQMTBJ2d4+m/qO6+ cFTAceXmIoFsN8+gFN3i8Is3u12u8xGudcBPvpoy4OoG Subject: Re: [PATCH v2] y2038: linux: Provide __time64 implementation Message-ID: <80d019c2-0ad1-c042-2a46-78377ebf34ff@linaro.org> Date: Fri, 16 Oct 2020 11:45:40 -0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20201016133218.20864-1-lukma@denx.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-14.4 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, KAM_SHORT, NICE_REPLY_A, RCVD_IN_DNSWL_NONE, 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: Fri, 16 Oct 2020 14:46:14 -0000 On 16/10/2020 10:32, Lukasz Majewski wrote: > In the glibc the time function can use vDSO (on power and x86 the > USE_IFUNC_TIME is defined), time syscall or 'default' time() from > ./time/time.c (as a fallback). > > In this patch the last function (time) has been refactored and moved > to ./sysdeps/unix/sysv/linux/time.c to be Linux specific. > > The new __time64 explicit 64 bit function for providing 64 bit value of > seconds after epoch (by internally calling __clock_gettime64) has been > introduced. > > Moreover, a 32 bit version - __time has been refactored to internally > use __time64. > > The __time is now supposed to be used on systems still supporting 32 bit > time (__TIMESIZE != 64) - hence the necessary check for time_t potential > overflow. > > The iFUNC vDSO direct call optimization has been removed from both i686 and > powerpc32 (USE_IFUNC_TIME is not defined for those architectures > anymore). The Linux kernel does not provide a y2038 safe implementation of > time neither it plans to provide it in the future, __clock_gettime64 > should be used instead. Keeping support for this optimization would require > to handle another build permutation (!__ASSUME_TIME64_SYSCALLS && > USE_IFUNC_TIME which adds more complexity and has limited use (since the > idea is to eventually have a y2038 safe glibc build). > > Build tests: > ./src/scripts/build-many-glibcs.py glibcs > > Run-time tests: > - Run specific tests on ARM/x86 32bit systems (qemu): > https://github.com/lmajewski/meta-y2038 and run tests: > https://github.com/lmajewski/y2038-tests/commits/master > > Above tests were performed with Y2038 redirection applied as well as > without to test proper usage of both __time64 and __time. LGTM, thanks. Reviewed-by: Adhemerval Zanella > > --- > Changes for v2: > - Add guards #ifdef __x86_64__ and #ifdef __powerpc64__ to avoid using time > vDSO on 32 bit powerpc and x86 > - Remove comment about time syscall conversion to 64 bit > - Avoid implicit checks on timer (shall be timer != NULL) > - Add comment about disabling vDSO optimization on powerpc32 and x86 > --- > include/time.h | 7 +++++ > sysdeps/unix/sysv/linux/powerpc/time.c | 4 ++- > sysdeps/unix/sysv/linux/time.c | 37 +++++++++++++++++++++++++- > sysdeps/unix/sysv/linux/x86/time.c | 4 ++- > 4 files changed, 49 insertions(+), 3 deletions(-) > > diff --git a/include/time.h b/include/time.h > index edf6cdf829..caf2af5e74 100644 > --- a/include/time.h > +++ b/include/time.h > @@ -317,6 +317,13 @@ extern int __timespec_get64 (struct __timespec64 *ts, int base); > libc_hidden_proto (__timespec_get64) > #endif > > +#if __TIMESIZE == 64 > +# define __time64 __time > +#else > +extern __time64_t __time64 (__time64_t *timer); > +libc_hidden_proto (__time64) > +#endif > + > /* Use in the clock_* functions. Size of the field representing the > actual clock ID. */ > #define CLOCK_IDFIELD_SIZE 3 Ok. > diff --git a/sysdeps/unix/sysv/linux/powerpc/time.c b/sysdeps/unix/sysv/linux/powerpc/time.c > index d10f449c5c..4fd5e138a3 100644 > --- a/sysdeps/unix/sysv/linux/powerpc/time.c > +++ b/sysdeps/unix/sysv/linux/powerpc/time.c > @@ -16,5 +16,7 @@ > License along with the GNU C Library; if not, see > . */ > > -#define USE_IFUNC_TIME > +#ifdef __powerpc64__ > +# define USE_IFUNC_TIME > +#endif > #include Ok. > diff --git a/sysdeps/unix/sysv/linux/time.c b/sysdeps/unix/sysv/linux/time.c > index 9d8e573c0a..80641d9ca4 100644 > --- a/sysdeps/unix/sysv/linux/time.c > +++ b/sysdeps/unix/sysv/linux/time.c > @@ -47,5 +47,40 @@ time (time_t *t) > } > # endif /* !SHARED */ > #else /* USE_IFUNC_TIME */ > -# include