Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1422802AbXBALM7 (ORCPT ); Thu, 1 Feb 2007 06:12:59 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1422800AbXBALMn (ORCPT ); Thu, 1 Feb 2007 06:12:43 -0500 Received: from styx.suse.cz ([82.119.242.94]:53764 "EHLO mail.suse.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751788AbXBALMf (ORCPT ); Thu, 1 Feb 2007 06:12:35 -0500 Message-Id: <20070201103753.655278000@jet.suse.cz> References: <20070201095952.589234000@jet.suse.cz> User-Agent: quilt/0.44-16.5 Date: Thu, 01 Feb 2007 10:59:55 +0100 From: jbohac@suse.cz To: Andi Kleen Cc: linux-kernel@vger.kernel.org, Jiri Bohac , Vojtech Pavlik , ssouhlal@freebsd.org, arjan@infradead.org, tglx@linutronix.de, johnstul@us.ibm.com, zippel@linux-m68k.org, andrea@suse.de Subject: [patch 3/9] Remove the support for the VXTIME_HPET timer mode Content-Disposition: inline; filename=remove_vxtime_hpet Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6123 Lines: 184 VXTIME_HPET will be replaced by a more generic "Master Timer" Signed-off-by: Jiri Bohac Index: linux-2.6.20-rc5/arch/x86_64/kernel/time.c =================================================================== --- linux-2.6.20-rc5.orig/arch/x86_64/kernel/time.c +++ linux-2.6.20-rc5/arch/x86_64/kernel/time.c @@ -101,13 +101,6 @@ static inline unsigned int do_gettimeoff return x; } -static inline unsigned int do_gettimeoffset_hpet(void) -{ - /* cap counter read to one tick to avoid inconsistencies */ - unsigned long counter = hpet_readl(HPET_COUNTER) - vxtime.last; - return (min(counter,hpet_tick) * vxtime.quot) >> US_SCALE; -} - unsigned int (*do_gettimeoffset)(void) = do_gettimeoffset_tsc; /* @@ -278,17 +271,6 @@ unsigned long long monotonic_clock(void) u32 last_offset, this_offset, offset; unsigned long long base; - if (vxtime.mode == VXTIME_HPET) { - do { - seq = read_seqbegin(&xtime_lock); - - last_offset = vxtime.last; - base = monotonic_base; - this_offset = hpet_readl(HPET_COUNTER); - } while (read_seqretry(&xtime_lock, seq)); - offset = (this_offset - last_offset); - offset *= NSEC_PER_TICK / hpet_tick; - } else { do { seq = read_seqbegin(&xtime_lock); @@ -297,7 +279,6 @@ unsigned long long monotonic_clock(void) } while (read_seqretry(&xtime_lock, seq)); this_offset = get_cycles_sync(); offset = cycles_2_ns(this_offset - last_offset); - } return base + offset; } EXPORT_SYMBOL(monotonic_clock); @@ -316,16 +297,6 @@ static noinline void handle_lost_ticks(i KERN_WARNING "Your time source seems to be instable or " "some driver is hogging interupts\n"); print_symbol("rip %s\n", get_irq_regs()->rip); - if (vxtime.mode == VXTIME_TSC && vxtime.hpet_address) { - printk(KERN_WARNING "Falling back to HPET\n"); - if (hpet_use_timer) - vxtime.last = hpet_readl(HPET_T0_CMP) - - hpet_tick; - else - vxtime.last = hpet_readl(HPET_COUNTER); - vxtime.mode = VXTIME_HPET; - do_gettimeoffset = do_gettimeoffset_hpet; - } /* else should fall back to PIT, but code missing. */ warned = 1; } else @@ -368,16 +339,6 @@ void main_timer_handler(void) tsc = get_cycles_sync(); - if (vxtime.mode == VXTIME_HPET) { - if (offset - vxtime.last > hpet_tick) { - lost = (offset - vxtime.last) / hpet_tick - 1; - } - - monotonic_base += - (offset - vxtime.last) * NSEC_PER_TICK / hpet_tick; - - vxtime.last = offset; - } else { offset = (((tsc - vxtime.last_tsc) * vxtime.tsc_quot) >> US_SCALE) - USEC_PER_TICK; @@ -387,7 +348,6 @@ void main_timer_handler(void) if (offset > USEC_PER_TICK) { lost = offset / USEC_PER_TICK; offset %= USEC_PER_TICK; - } monotonic_base += cycles_2_ns(tsc - vxtime.last_tsc); @@ -465,20 +425,6 @@ unsigned long long sched_clock(void) { unsigned long a = 0; -#if 0 - /* Don't do a HPET read here. Using TSC always is much faster - and HPET may not be mapped yet when the scheduler first runs. - Disadvantage is a small drift between CPUs in some configurations, - but that should be tolerable. */ - if (__vxtime.mode == VXTIME_HPET) - return (hpet_readl(HPET_COUNTER) * vxtime.quot) >> US_SCALE; -#endif - - /* Could do CPU core sync here. Opteron can execute rdtsc speculatively, - which means it is not completely exact and may not be monotonous between - CPUs. But the errors should be too small to matter for scheduling - purposes. */ - rdtscll(a); return cycles_2_ns(a); } @@ -961,18 +907,8 @@ void time_init_gtod(void) else vgetcpu_mode = VGETCPU_LSL; - if (vxtime.hpet_address && notsc) { - timetype = hpet_use_timer ? "HPET" : "PIT/HPET"; - if (hpet_use_timer) - vxtime.last = hpet_readl(HPET_T0_CMP) - hpet_tick; - else - vxtime.last = hpet_readl(HPET_COUNTER); - vxtime.mode = VXTIME_HPET; - do_gettimeoffset = do_gettimeoffset_hpet; - } else { timetype = hpet_use_timer ? "HPET/TSC" : "PIT/TSC"; vxtime.mode = VXTIME_TSC; - } printk(KERN_INFO "time.c: Using %ld.%06ld MHz WALL %s GTOD %s timer.\n", vxtime_hz / 1000000, vxtime_hz % 1000000, timename, timetype); @@ -1031,12 +967,6 @@ static int timer_resume(struct sys_devic write_seqlock_irqsave(&xtime_lock,flags); xtime.tv_sec = sec; xtime.tv_nsec = 0; - if (vxtime.mode == VXTIME_HPET) { - if (hpet_use_timer) - vxtime.last = hpet_readl(HPET_T0_CMP) - hpet_tick; - else - vxtime.last = hpet_readl(HPET_COUNTER); - } else vxtime.last_tsc = get_cycles_sync(); write_sequnlock_irqrestore(&xtime_lock,flags); jiffies += sleep_length; Index: linux-2.6.20-rc5/arch/x86_64/kernel/vsyscall.c =================================================================== --- linux-2.6.20-rc5.orig/arch/x86_64/kernel/vsyscall.c +++ linux-2.6.20-rc5/arch/x86_64/kernel/vsyscall.c @@ -72,18 +72,9 @@ static __always_inline void do_vgettimeo sec = __xtime.tv_sec; usec = __xtime.tv_nsec / 1000; - if (__vxtime.mode != VXTIME_HPET) { - t = get_cycles_sync(); - if (t < __vxtime.last_tsc) - t = __vxtime.last_tsc; - usec += ((t - __vxtime.last_tsc) * - __vxtime.tsc_quot) >> 32; - /* See comment in x86_64 do_gettimeofday. */ - } else { usec += ((readl((void __iomem *) fix_to_virt(VSYSCALL_HPET) + 0xf0) - __vxtime.last) * __vxtime.quot) >> 32; - } } while (read_seqretry(&__xtime_lock, sequence)); tv->tv_sec = sec + usec / 1000000; Index: linux-2.6.20-rc5/include/asm-x86_64/vsyscall.h =================================================================== --- linux-2.6.20-rc5.orig/include/asm-x86_64/vsyscall.h +++ linux-2.6.20-rc5/include/asm-x86_64/vsyscall.h @@ -25,7 +25,6 @@ enum vsyscall_num { #define __section_xtime_lock __attribute__ ((unused, __section__ (".xtime_lock"), aligned(16))) #define VXTIME_TSC 1 -#define VXTIME_HPET 2 #define VGETCPU_RDTSCP 1 #define VGETCPU_LSL 2 -- - 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/