From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934268AbaJ3NYs (ORCPT ); Thu, 30 Oct 2014 09:24:48 -0400 Received: from www.linutronix.de ([62.245.132.108]:35115 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933727AbaJ3NYr (ORCPT ); Thu, 30 Oct 2014 09:24:47 -0400 Date: Thu, 30 Oct 2014 14:24:41 +0100 (CET) From: Thomas Gleixner To: "pang.xunlei" cc: linux-kernel@vger.kernel.org, rtc-linux@googlegroups.com, xen-devel@lists.xenproject.org, John Stultz , Alessandro Zummo , Stefano Stabellini Subject: Re: [RFC PATCH v2 01/11] time: Add do_settimeofday64() safe version(using timespec64) In-Reply-To: <1414667745-7703-2-git-send-email-pang.xunlei@linaro.org> Message-ID: References: <1414667745-7703-1-git-send-email-pang.xunlei@linaro.org> <1414667745-7703-2-git-send-email-pang.xunlei@linaro.org> User-Agent: Alpine 2.11 (DEB 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 30 Oct 2014, pang.xunlei wrote: Your subject line > time: Add do_settimeofday64() safe version(using timespec64) is confusing at best. time: Provide y2038 safe do_settimeofday() replacement That explains what the patch is doing in a very precice way. > /** > - * do_settimeofday - Sets the time of day > - * @tv: pointer to the timespec variable containing the new time > + * do_settimeofday64 - Sets the time of day > + * @ts: pointer to the timespec64 variable containing the new time > * > * Sets the time of day to the new time and update NTP and notify hrtimers > + * Safe version for 2038 safety. I rather put this into the function description above: + * do_settimeofday64 - Sets the time of day. 2038 safe. Way simpler to grep for. > */ > -int do_settimeofday(const struct timespec *tv) > +int do_settimeofday64(const struct timespec64 *ts) > { > struct timekeeper *tk = &tk_core.timekeeper; > - struct timespec64 ts_delta, xt, tmp; > + struct timespec64 ts_delta, xt; > unsigned long flags; > > - if (!timespec_valid_strict(tv)) > + if (!timespec64_valid_strict(ts)) > return -EINVAL; > > raw_spin_lock_irqsave(&timekeeper_lock, flags); > @@ -723,13 +724,12 @@ int do_settimeofday(const struct timespec *tv) > timekeeping_forward_now(tk); > > xt = tk_xtime(tk); > - ts_delta.tv_sec = tv->tv_sec - xt.tv_sec; > - ts_delta.tv_nsec = tv->tv_nsec - xt.tv_nsec; > + ts_delta.tv_sec = ts->tv_sec - xt.tv_sec; > + ts_delta.tv_nsec = ts->tv_nsec - xt.tv_nsec; > > tk_set_wall_to_mono(tk, timespec64_sub(tk->wall_to_monotonic, ts_delta)); > > - tmp = timespec_to_timespec64(*tv); > - tk_set_xtime(tk, &tmp); > + tk_set_xtime(tk, ts); > > timekeeping_update(tk, TK_CLEAR_NTP | TK_MIRROR | TK_CLOCK_WAS_SET); > > @@ -741,6 +741,22 @@ int do_settimeofday(const struct timespec *tv) > > return 0; > } > +EXPORT_SYMBOL(do_settimeofday64); EXPORT_SYMBOL_GPL please. > + > +/** > + * do_settimeofday - Sets the time of day > + * @tv: pointer to the timespec variable containing the new time > + * > + * Sets the time of day to the new time and update NTP and notify hrtimers > + * TODO: [2038 safety] should be replaced by do_settimeofday64(). The TODO is not to replace do_settimeofday() by do_settimeofday64(). The TODO is to fix the call sites. So instead of adding this you can simply say: + * do_settimeofday - Sets the time of day. Deprecated. Use do_settimeofday64() We want things like this easy to find and not be burried in some cryptic comment. Thanks, tglx