- 13 12月, 2008 1 次提交
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由 Rusty Russell 提交于
Impact: change calling convention of existing clock_event APIs struct clock_event_timer's cpumask field gets changed to take pointer, as does the ->broadcast function. Another single-patch change. For safety, we BUG_ON() in clockevents_register_device() if it's not set. Signed-off-by: NRusty Russell <rusty@rustcorp.com.au> Cc: Ingo Molnar <mingo@elte.hu>
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- 14 7月, 2008 1 次提交
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由 Kumar Gala 提交于
For some reason long ago I decided that we should zero out the time base when we calibrate the decrementer. The problem is that this can be harmful in SMP systems where the firmware has already synchronized the time bases on the various cores. Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
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- 26 6月, 2008 1 次提交
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由 Jens Axboe 提交于
It's not even passed on to smp_call_function() anymore, since that was removed. So kill it. Acked-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Reviewed-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: NJens Axboe <jens.axboe@oracle.com>
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- 14 5月, 2008 1 次提交
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由 Michael Ellerman 提交于
Make a few things static in lparcfg.c Make init and exit routines static in rtas_flash.c Make things static in rtas_pci.c Make some functions static in rtas.c Make fops static in rtas-proc.c Remove unneeded extern for do_gtod in smp.c Make clocksource_init() static in time.c Make last_tick_len and ticklen_to_xs static in time.c Move the declaration of the pvr per-cpu into smp.h Make kexec_smp_down() and kexec_stack static in machine_kexec_64.c Don't return void in arch_teardown_msi_irqs() in msi.c Move declaration of GregorianDay()into asm/time.h Signed-off-by: NMichael Ellerman <michael@ellerman.id.au> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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- 01 5月, 2008 2 次提交
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由 Roman Zippel 提交于
As TICK_LENGTH_SHIFT is used for more than just the tick length, the name isn't quite approriate anymore, so this renames it to NTP_SCALE_SHIFT. Signed-off-by: NRoman Zippel <zippel@linux-m68k.org> Cc: john stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Roman Zippel 提交于
This changes time_freq to a 64bit value and makes it static (the only outside user had no real need to modify it). Intermediate values were already 64bit, so the change isn't that big, but it saves a little in shifts by replacing SHIFT_NSEC with TICK_LENGTH_SHIFT. PPM_SCALE is then used to convert between user space and kernel space representation. Signed-off-by: NRoman Zippel <zippel@linux-m68k.org> Cc: john stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 07 2月, 2008 1 次提交
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由 Michael Neuling 提交于
This moves the ability to scale cputime into generic code. This allows us to fix the issue in kernel/timer.c (noticed by Balbir) where we could only add an unscaled value to the scaled utime/stime. This adds a cputime_to_scaled function. As before, the POWERPC version does the scaling based on the last SPURR/PURR ratio calculated. The generic and s390 (only other arch to implement asm/cputime.h) versions are both NOPs. Also moves the SPURR and PURR snapshots closer. Signed-off-by: NMichael Neuling <mikey@neuling.org> Cc: Jay Lan <jlan@engr.sgi.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 21 12月, 2007 1 次提交
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由 Scott Wood 提交于
These hooks ensure that a decrementer interrupt is not pending when suspending; otherwise, problems may occur on 6xx/7xx/7xxx-based systems (except for powermacs, which use a separate suspend path). For example, with deep sleep on the 831x, a pending decrementer will cause a system freeze because the SoC thinks the decrementer interrupt would have woken the system, but the core must have interrupts disabled due to the setup required for deep sleep. Changed via-pmu.c to use the new ppc_md hooks, and made the arch_* functions call the generic_* functions unconditionally. -- paulus Signed-off-by: NScott Wood <scottwood@freescale.com> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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- 20 12月, 2007 5 次提交
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由 Milton Miller 提交于
We have multiple calls to has_feature being inlined, but gcc can't be sure that the store via get_paca() doesn't alias the path to cur_cpu_spec->feature. Reorder to put the calls to read_purr and read_spurr adjacent to each other. To add a sense of consistency, reorder the remaining lines to perform parallel steps on purr and scaled purr of each line instead of calculating and then using one value before going on to the next. In addition, we can tell gcc that no SPURR means no PURR. The test is completely hidden in the PURR case, and in the !PURR case the second test is eliminated resulting in the simple register copy in the out-of-line branch. Further, gcc sees get_paca()->system_time referenced several times and allocates a register to address it (shadowing r13) instead of caching its value. Reading into a local varable saves the shadow of r13 and removes a potentially duplicate load (between the nested if and its parent). Signed-off-by: NMilton Miller <miltonm@bga.com> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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由 Milton Miller 提交于
If CPU_FTR_PURR is not set, we will never set cpu_purr_data->initialized. Checking via __get_cpu_var on 64 bit avoids one dependent load compared to cpu_has_feature in the not-present case, and is always required when it is present. The code is under CONFIG_VIRT_CPU_ACCOUNTING so 32 bit will not be affected. Signed-off-by: NMilton Miller <miltonm@bga.com> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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由 Milton Miller 提交于
timer_interrupt() was calculating per_cpu_offset several times, having to start from the toc because of potential aliasing issues. Placing both decrementer per_cpu varables in a struct and calculating the address once with __get_cpu_var results in better code on both 32 and 64 bit. Signed-off-by: NMilton Miller <miltonm@bga.com> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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由 Milton Miller 提交于
Use __get_cpu_var(x) instead of per_cpu(x, smp_processor_id()), as it is optimized on ppc64 to access the current cpu's per-cpu offset directly; it's local_paca.offset instead of TOC->paca[local_paca->processor_id].offset. This is the trivial portion, two functions with one use each. Signed-off-by: NMilton Miller <miltonm@bga.com> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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由 Milton Miller 提交于
as its only called from time_init, which is __init. Also remove unneeded forward declaration. Signed-off-by: NMilton Miller <miltonm@bga.com> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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- 20 11月, 2007 1 次提交
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由 Michael Neuling 提交于
If we get no user time and no system time allocated since the last account_system_vtime, the system to user time ratio estimate can end up dividing by zero. This was causing a problem noticed by Balbir Singh. Signed-off-by: NMichael Neuling <mikey@neuling.org> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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- 13 11月, 2007 1 次提交
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由 Tony Breeds 提交于
These don't need to be seen by everyone on every boot. Signed-off-by: NTony Breeds <tony@bakeyournoodle.com> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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- 10 11月, 2007 1 次提交
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由 Paul Mackerras 提交于
Since powerpc started using CONFIG_GENERIC_CLOCKEVENTS, the deterministic CPU accounting (CONFIG_VIRT_CPU_ACCOUNTING) has been broken on powerpc, because we end up counting user time twice: once in timer_interrupt() and once in update_process_times(). This fixes the problem by pulling the code in update_process_times that updates utime and stime into a separate function called account_process_tick. If CONFIG_VIRT_CPU_ACCOUNTING is not defined, there is a version of account_process_tick in kernel/timer.c that simply accounts a whole tick to either utime or stime as before. If CONFIG_VIRT_CPU_ACCOUNTING is defined, then arch code gets to implement account_process_tick. This also lets us simplify the s390 code a bit; it means that the s390 timer interrupt can now call update_process_times even when CONFIG_VIRT_CPU_ACCOUNTING is turned on, and can just implement a suitable account_process_tick(). account_process_tick() now takes the task_struct * as an argument. Tested both with and without CONFIG_VIRT_CPU_ACCOUNTING. Signed-off-by: NPaul Mackerras <paulus@samba.org> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 08 11月, 2007 1 次提交
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由 Paul Mackerras 提交于
The decrementer in Book E and 4xx processors interrupts on the transition from 1 to 0, rather than on the 0 to -1 transition as on 64-bit server and 32-bit "classic" (6xx/7xx/7xxx) processors. At the moment we subtract 1 from the count of how many decrementer ticks are required before the next interrupt before putting it into the decrementer, which is correct for server/classic processors, but could possibly cause the interrupt to happen too early on Book E and 4xx if the timebase/decrementer frequency is low. This fixes the problem by making set_dec subtract 1 from the count for server and classic processors, instead of having the callers subtract 1. Since set_dec already had a bunch of ifdefs to handle different processor types, there is no net increase in ugliness. :) Note that calling set_dec(0) may not generate an interrupt on some processors. To make sure that decrementer_set_next_event always calls set_dec with an interval of at least 1 tick, we set min_delta_ns of the decrementer_clockevent to correspond to 2 ticks (2 rather than 1 to compensate for truncations in the conversions between ticks and ns). This also removes a redundant call to set the decrementer to 0x7fffffff - it was already set to that earlier in timer_interrupt. Signed-off-by: NPaul Mackerras <paulus@samba.org>
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- 19 10月, 2007 1 次提交
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由 Michael Neuling 提交于
This adds POWERPC specific hooks for scaled time accounting. POWER6 includes a SPURR register. The SPURR is based off the PURR register but is scaled based on CPU frequency and issue rates. This gives a more accurate account of the instructions used per task. The PURR and timebase will be constant relative to the wall clock, irrespective of the CPU frequency. This implementation reads the SPURR register in account_system_vtime which is only call called on context witch and hard and soft irq entry and exit. The percentage of user and system time is then estimated using the ratio of these accounted by the PURR. If the SPURR is not present, the PURR read. An earlier implementation of this patch read the SPURR whenever the PURR was read, which included the system call entry and exit path. Unfortunately this showed a performance regression on lmbench runs, so was re-implemented. I've included the lmbench results here when run bare metal on POWER6. 1st column is the unpatch results. 2nd column is the results using the below patch and the 3rd is the % diff of these results from the base. 4th and 5th columns are the results and % differnce from the base using the older patch (SPURR read in syscall entry/exit path). Base Scaled-Acct SPURR-in-syscall Result Result % diff Result % diff Simple syscall: 0.3086 0.3086 0.0000 0.3452 11.8600 Simple read: 0.4591 0.4671 1.7425 0.5044 9.86713 Simple write: 0.4364 0.4366 0.0458 0.4731 8.40971 Simple stat: 2.0055 2.0295 1.1967 2.0669 3.06158 Simple fstat: 0.5962 0.5876 -1.442 0.6368 6.80979 Simple open/close: 3.1283 3.1009 -0.875 3.2088 2.57328 Select on 10 fd's: 0.8554 0.8457 -1.133 0.8667 1.32101 Select on 100 fd's: 3.5292 3.6329 2.9383 3.6664 3.88756 Select on 250 fd's: 7.9097 8.1881 3.5197 8.2242 3.97613 Select on 500 fd's: 15.2659 15.836 3.7357 15.873 3.97814 Select on 10 tcp fd's: 0.9576 0.9416 -1.670 0.9752 1.83792 Select on 100 tcp fd's: 7.248 7.2254 -0.311 7.2685 0.28283 Select on 250 tcp fd's: 17.7742 17.707 -0.375 17.749 -0.1406 Select on 500 tcp fd's: 35.4258 35.25 -0.496 35.286 -0.3929 Signal handler installation: 0.6131 0.6075 -0.913 0.647 5.52927 Signal handler overhead: 2.0919 2.1078 0.7600 2.1831 4.35967 Protection fault: 0.7345 0.7478 1.8107 0.8031 9.33968 Pipe latency: 33.006 16.398 -50.31 33.475 1.42368 AF_UNIX sock stream latency: 14.5093 30.910 113.03 30.715 111.692 Process fork+exit: 219.8 222.8 1.3648 229.37 4.35623 Process fork+execve: 876.14 873.28 -0.32 868.66 -0.8533 Process fork+/bin/sh -c: 2830 2876.5 1.6431 2958 4.52296 File /var/tmp/XXX write bw: 1193497 1195536 0.1708 118657 -0.5799 Pagefaults on /var/tmp/XXX: 3.1272 3.2117 2.7020 3.2521 3.99398 Also, kernel compile times show no difference with this patch applied. [pbadari@us.ibm.com: Avoid unnecessary PURR reading] Signed-off-by: NMichael Neuling <mikey@neuling.org> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Jay Lan <jlan@engr.sgi.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: NBadari Pulavarty <pbadari@us.ibm.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 17 10月, 2007 1 次提交
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由 Anton Blanchard 提交于
The clockevent bootup message only needs to be KERN_INFO. Signed-off-by: NAnton Blanchard <anton@samba.org> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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- 11 10月, 2007 2 次提交
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由 Paul Mackerras 提交于
In testing the new clocksource and clockevent code on a PPC601 processor, I discovered that the clockevent multiplier value for the decrementer clockevent was overflowing. Because the RTCL register in the 601 effectively counts at 1GHz (it doesn't actually, but it increases by 128 every 128ns), and the shift value was 32, that meant the multiplier value had to be 2^32, which won't fit in an unsigned long on 32-bit. The same problem would arise on any platform where the timebase frequency was 1GHz or more (not that we actually have any such machines today). This fixes it by reducing the shift value to 16. Doing the calculations with a resolution of 2^-16 nanoseconds (15 femtoseconds) should be quite adequate. :) Signed-off-by: NPaul Mackerras <paulus@samba.org>
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由 Paul Mackerras 提交于
On old powermacs, we sometimes set the decrementer to 1 in order to trigger a decrementer interrupt, which we use to handle an interrupt that was pending at the time when it was re-enabled. This was causing the decrementer clock event device to call the event function for the next event early, which was causing problems when high-res timers were not enabled. This fixes the problem by recording the timebase value at which the next event should occur, and checking the current timebase against the recorded value in timer_interrupt. If it isn't time for the next event, it just reprograms the decrementer and returns. This also subtracts 1 from the value stored into the decrementer, which is appropriate because the decrementer interrupts on the transition from 0 to -1, not when the decrementer reaches 0. Signed-off-by: NPaul Mackerras <paulus@samba.org>
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- 03 10月, 2007 3 次提交
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由 Tony Breeds 提交于
This registers a clock event structure for the decrementer and turns on CONFIG_GENERIC_CLOCKEVENTS, which means that we now don't need most of timer_interrupt(), since the work is done in generic code. For secondary CPUs, their decrementer clockevent is registered when the CPU comes up (the generic code automatically removes the clockevent when the CPU goes down). Signed-off-by: NTony Breeds <tony@bakeyournoodle.com> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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由 Tony Breeds 提交于
Signed-off-by: NTony Breeds <tony@bakeyournoodle.com> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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由 Tony Breeds 提交于
With these functions implemented we cooperate better with the generic timekeeping code. This obsoletes the need for the timer sysdev as a bonus. Signed-off-by: NTony Breeds <tony@bakeyournoodle.com> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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- 19 9月, 2007 1 次提交
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由 Benjamin Herrenschmidt 提交于
Recent changes to the timekeeping code broke support for the PowerPC 601 processor which doesn't have the usual timebase facility but a slightly different thing called (yuck) the RTC. This fixes it, boot tested on an old 601 based PowerMac 7200. Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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- 20 8月, 2007 1 次提交
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由 Josh Boyer 提交于
Allow generic_calibrate_decr to work for 40x platforms. Given that the hardware behavior is identical, this also changes the set_dec function to reload the PIT on 40x to match the behavior 44x currently has. Signed-off-by: NJosh Boyer <jwboyer@linux.vnet.ibm.com>
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- 17 8月, 2007 1 次提交
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由 Jesper Juhl 提交于
This removes several duplicate includes from arch/powerpc/. Signed-off-by: NJesper Juhl <jesper.juhl@gmail.com> Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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- 21 7月, 2007 1 次提交
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由 Bob Nelson 提交于
From: Maynard Johnson <mpjohn@us.ibm.com> This patch updates the existing arch/powerpc/oprofile/op_model_cell.c to add in the SPU profiling capabilities. In addition, a 'cell' subdirectory was added to arch/powerpc/oprofile to hold Cell-specific SPU profiling code. Exports spu_set_profile_private_kref and spu_get_profile_private_kref which are used by OProfile to store private profile information in spufs data structures. Also incorporated several fixes from other patches (rrn). Check pointer returned from kzalloc. Eliminated unnecessary cast. Better error handling and cleanup in the related area. 64-bit unsigned long parameter was being demoted to 32-bit unsigned int and eventually promoted back to unsigned long. Signed-off-by: NCarl Love <carll@us.ibm.com> Signed-off-by: NMaynard Johnson <mpjohn@us.ibm.com> Signed-off-by: NBob Nelson <rrnelson@us.ibm.com> Signed-off-by: NArnd Bergmann <arnd.bergmann@de.ibm.com> Acked-by: NPaul Mackerras <paulus@samba.org>
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- 10 7月, 2007 1 次提交
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由 Tony Breeds 提交于
When booting a current kernel with CONFIG_PRINTK_TIME enabled you'll see messages like: [ 0.000000] time_init: decrementer frequency = 188.044000 MHz [ 0.000000] time_init: processor frequency = 1504.352000 MHz [3712914.436297] Console: colour dummy device 80x25 This cause by the initialisation of tb_to_ns_scale in time_init(), suddenly the multiplication in sched_clock() now does something :). This patch modifies sched_clock() to report the offset since the machine booted so the same printk's now look like: [ 0.000000] time_init: decrementer frequency = 188.044000 MHz [ 0.000000] time_init: processor frequency = 1504.352000 MHz [ 0.000135] Console: colour dummy device 80x25 Effectivly including the uptime in printk()s. This patch makes tb_to_ns_scale and tb_to_ns_shift static and read_mostly for good measure. Signed-off-by: NTony Breeds <tony@bakeyournoodle.com> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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- 28 6月, 2007 1 次提交
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由 Tony Breeds 提交于
Currently iSeries will recalibrate the cputime_factors in the first settimeofday() call. It seems the reason for doing this is to ensure a resaonable time delta after time_init(). On current kernels (with udev), this call is made 40-60 seconds into the boot process, by moving it to a late initcall it is called approximately 5 seconds after time_init() is called. This is sufficient to recalibrate the timebase. Signed-off-by: NTony Breeds <tony@bakeyournoodle.com> CC: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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- 25 6月, 2007 2 次提交
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由 Michael Neuling 提交于
For POWERPC, stolen time accounts for cycles lost to the hypervisor or PURR cycles attributed to the other SMT thread. Hence, when a PURR is available, we should still calculate stolen time, irrespective of being virtualised. Signed-off-by: NMichael Neuling <mikey@neuling.org> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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由 Nathan Lynch 提交于
cpu_purr_data is a per-cpu array used to account for stolen time on partitioned systems. It used to be the case that cpus accessed each others' cpu_purr_data, so each entry was protected by a spinlock. However, the code was reworked ("Simplify stolen time calculation") with the result that each cpu accesses its own cpu_purr_data and not those of other cpus. This means we can get rid of the spinlock as long as we're careful to disable interrupts when accessing cpu_purr_data in process context. Signed-off-by: NNathan Lynch <ntl@pobox.com> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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- 12 5月, 2007 1 次提交
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由 will schmidt 提交于
Greatly simplify the function smp_space_timers. The stolen time calculation (per comment within the code) doesn't need the half-jiffy stagger any more. There isn't an issue with bouncing off global locks, so we really shouldn't need any sort of staggering at all. However, the last_jiffy value still needs to be set. This removes the extra stagger logic, and just sets the values. This change should benefit applications that rely on barrier synchronization, and will help cut down OS jitter. Boot tested across the board (G5,power3,power4,power5,970mp blade). Signed-off-by: NWill Schmidt <will_schmidt@vnet.ibm.com> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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- 13 4月, 2007 1 次提交
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由 Stephen Rothwell 提交于
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au> Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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- 04 12月, 2006 1 次提交
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由 Stephen Rothwell 提交于
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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- 22 11月, 2006 1 次提交
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由 Kim Phillips 提交于
This reverts commit 7a69af63. As advised by David Brownell: http://marc.theaimsgroup.com/?l=linux-kernel&m=116387226902131&w=2Signed-off-by: NKim Phillips <kim.phillips@freescale.com> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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- 23 10月, 2006 1 次提交
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由 Stephen Rothwell 提交于
In calculating stolen time, we were trying to actually account for time spent in the hypervisor. We don't really have enough information to do that accurately, so don't try. Instead, we now calculate stolen time as time that the current cpu thread is not actually dispatching instructions. On chips without a PURR, we cannot do this, so stolen time will always be zero. On chips with a PURR, this is merely the difference between the elapsed PURR values and the elapsed TB values. This gives us much more sane vaules from tools such as mpstat, even if they are still a bit strange e.g. 2 busy threads on one cpu will both appear to have 50% user time and 50% stolen time while 1 busy thread on a cpu will look like 100% user on one of them and 100% idle on the other. Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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- 07 10月, 2006 1 次提交
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由 Olaf Hering 提交于
Remove struct pt_regs * from all handlers. Also remove the regs argument from get_irq() functions. Compile tested with arch/powerpc/config/* and arch/ppc/configs/prep_defconfig Signed-off-by: NOlaf Hering <olaf@aepfle.de> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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- 05 10月, 2006 1 次提交
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由 David Howells 提交于
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: NDavid Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
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- 02 10月, 2006 1 次提交
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由 Kim Phillips 提交于
Add powerpc get/set_rtc_time interface to new generic rtc class. This abstracts rtc chip specific code from the platform code for rtc-over-i2c platforms. Specific RTC chip support is now configured under Device Drivers -> Real Time Clock. Setting time of day from the RTC on startup is also configurable. this time without the potentially platform breaking initcall. Signed-off-by: NKim Phillips <kim.phillips@freescale.com> Signed-off-by: NPaul Mackerras <paulus@samba.org>
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