Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752822AbZLRAiN (ORCPT ); Thu, 17 Dec 2009 19:38:13 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751880AbZLRAiN (ORCPT ); Thu, 17 Dec 2009 19:38:13 -0500 Received: from e6.ny.us.ibm.com ([32.97.182.146]:34829 "EHLO e6.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751676AbZLRAiM (ORCPT ); Thu, 17 Dec 2009 19:38:12 -0500 Subject: [PATCH 1/3] Convert cris to arch_gettimeoffset() From: john stultz To: starvik@axis.com, jesper.nilsson@axis.com Cc: lkml , Andrew Morton , linux-cris-kernel@axis.com Content-Type: text/plain; charset="UTF-8" Date: Thu, 17 Dec 2009 16:38:06 -0800 Message-ID: <1261096687.3466.12.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.28.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3743 Lines: 129 This patch converts cris to use GENERIC_TIME via the arch_getoffset() infrastructure, reducing the amount of arch specific code we need to maintain. The cris architecture is one of the last 3 arches that need to be converted. This patch applies on top of Linus' current -git tree I've taken my best swing at converting this, but I'm not 100% confident I got it right. My cross-compiler is now out of date (gcc4.2) so I wasn't able to check if it compiled. Any assistance from arch maintainers or testers to get this merged would be great. thanks -john Signed-off-by: John Stultz --- Kconfig | 6 +++++ kernel/time.c | 68 +--------------------------------------------------------- 2 files changed, 8 insertions(+), 66 deletions(-) diff --git a/arch/cris/Kconfig b/arch/cris/Kconfig index 7adac38..059eac6 100644 --- a/arch/cris/Kconfig +++ b/arch/cris/Kconfig @@ -20,6 +20,12 @@ config RWSEM_GENERIC_SPINLOCK config RWSEM_XCHGADD_ALGORITHM bool +config GENERIC_TIME + def_bool y + +config ARCH_USES_GETTIMEOFFSET + def_bool y + config GENERIC_IOMAP bool default y diff --git a/arch/cris/kernel/time.c b/arch/cris/kernel/time.c index 074fe7d..a05dd31 100644 --- a/arch/cris/kernel/time.c +++ b/arch/cris/kernel/time.c @@ -42,75 +42,11 @@ unsigned long loops_per_usec; extern unsigned long do_slow_gettimeoffset(void); static unsigned long (*do_gettimeoffset)(void) = do_slow_gettimeoffset; -/* - * This version of gettimeofday has near microsecond resolution. - * - * Note: Division is quite slow on CRIS and do_gettimeofday is called - * rather often. Maybe we should do some kind of approximation here - * (a naive approximation would be to divide by 1024). - */ -void do_gettimeofday(struct timeval *tv) -{ - unsigned long flags; - signed long usec, sec; - local_irq_save(flags); - usec = do_gettimeoffset(); - - /* - * If time_adjust is negative then NTP is slowing the clock - * so make sure not to go into next possible interval. - * Better to lose some accuracy than have time go backwards.. - */ - if (unlikely(time_adjust < 0) && usec > tickadj) - usec = tickadj; - - sec = xtime.tv_sec; - usec += xtime.tv_nsec / 1000; - local_irq_restore(flags); - - while (usec >= 1000000) { - usec -= 1000000; - sec++; - } - - tv->tv_sec = sec; - tv->tv_usec = usec; -} - -EXPORT_SYMBOL(do_gettimeofday); - -int do_settimeofday(struct timespec *tv) +u32 arch_gettimeoffset(void) { - time_t wtm_sec, sec = tv->tv_sec; - long wtm_nsec, nsec = tv->tv_nsec; - - if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC) - return -EINVAL; - - write_seqlock_irq(&xtime_lock); - /* - * This is revolting. We need to set "xtime" correctly. However, the - * value in this location is the value at the most recent update of - * wall time. Discover what correction gettimeofday() would have - * made, and then undo it! - */ - nsec -= do_gettimeoffset() * NSEC_PER_USEC; - - wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec); - wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec); - - set_normalized_timespec(&xtime, sec, nsec); - set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec); - - ntp_clear(); - write_sequnlock_irq(&xtime_lock); - clock_was_set(); - return 0; + return do_gettimeoffset() * 1000; } -EXPORT_SYMBOL(do_settimeofday); - - /* * BUG: This routine does not handle hour overflow properly; it just * sets the minutes. Usually you'll only notice that after reboot! -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/