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2009-04-21clocksource: pass clocksource to read() callbackMagnus Damm
Pass clocksource pointer to the read() callback for clocksources. This allows us to share the callback between multiple instances. [hugh@veritas.com: fix powerpc build of clocksource pass clocksource mods] [akpm@linux-foundation.org: cleanup] Signed-off-by: Magnus Damm <damm@igel.co.jp> Acked-by: John Stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01Merge branch 'release' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6 * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6: (29 commits) [IA64] BUG to BUG_ON changes [IA64] Fix typo/thinko in arch/ia64/sn/kernel/sn2/sn2_smp.c ia64: remove some warnings. ia64/xen: fix the link error. ia64/pv_ops/bp/xen: implemented binary patchable pv_cpu_ops. ia64/pv_ops/binary patch: define paravirt_dv_serialize_data() and suppress false positive warning. ia64/pv_ops/bp/module: support binary patching for kernel module. ia64/pv_ops: implement binary patching optimization for native. ia64/pv_op/binarypatch: add helper functions to support binary patching for paravirt_ops. ia64/pv_ops/xen/gate.S: xen gate page paravirtualization ia64/pv_ops: paravirtualize gate.S. ia64/pv_ops: move down __kernel_syscall_via_epc. ia64/pv_ops/xen: define xen specific gate page. ia64/pv_ops: gate page paravirtualization. ia64/pv_ops/xen/pv_time_ops: implement sched_clock. ia64/pv_ops/pv_time_ops: add sched_clock hook. ia64/pv_ops/xen: paravirtualize read/write ar.itc and ar.itm ia64/pv_ops: paravirtualize mov = ar.itc. ia64/pv_ops/pvchecker: support mov = ar.itc paravirtualization ia64/pv_ops: paravirtualize fsys.S. ...
2009-04-01rtc: add platform driver for EFIdann frazier
Munge Stephane Eranian's efirtc.c code into an rtc platform driver [akpm@linux-foundation.org: use is_leap_year()] Signed-off-by: dann frazier <dannf@hp.com> Cc: Alessandro Zummo <alessandro.zummo@towertech.it> Cc: stephane eranian <eranian@googlemail.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-26ia64/pv_ops/pv_time_ops: add sched_clock hook.Isaku Yamahata
add sched_clock() hook to paravirtualize sched_clock(). ia64 sched_clock() is based on ar.itc which isn't stable on virtualized environment because vcpu may move around on pcpus. So it needs paravirtualization. Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp> Signed-off-by: Tony Luck <tony.luck@intel.com>
2008-12-31[PATCH] idle cputime accountingMartin Schwidefsky
The cpu time spent by the idle process actually doing something is currently accounted as idle time. This is plain wrong, the architectures that support VIRT_CPU_ACCOUNTING=y can do better: distinguish between the time spent doing nothing and the time spent by idle doing work. The first is accounted with account_idle_time and the second with account_system_time. The architectures that use the account_xxx_time interface directly and not the account_xxx_ticks interface now need to do the check for the idle process in their arch code. In particular to improve the system vs true idle time accounting the arch code needs to measure the true idle time instead of just testing for the idle process. To improve the tick based accounting as well we would need an architecture primitive that can tell us if the pt_regs of the interrupted context points to the magic instruction that halts the cpu. In addition idle time is no more added to the stime of the idle process. This field now contains the system time of the idle process as it should be. On systems without VIRT_CPU_ACCOUNTING this will always be zero as every tick that occurs while idle is running will be accounted as idle time. This patch contains the necessary common code changes to be able to distinguish idle system time and true idle time. The architectures with support for VIRT_CPU_ACCOUNTING need some changes to exploit this. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-31[PATCH] fix scaled & unscaled cputime accountingMartin Schwidefsky
The utimescaled / stimescaled fields in the task structure and the global cpustat should be set on all architectures. On s390 the calls to account_user_time_scaled and account_system_time_scaled never have been added. In addition system time that is accounted as guest time to the user time of a process is accounted to the scaled system time instead of the scaled user time. To fix the bugs and to prevent future forgetfulness this patch merges account_system_time_scaled into account_system_time and account_user_time_scaled into account_user_time. Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Jeremy Fitzhardinge <jeremy@xensource.com> Cc: Chris Wright <chrisw@sous-sol.org> Cc: Michael Neuling <mikey@neuling.org> Acked-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-07-17Pull pvops into release branchTony Luck
2008-06-30[IA64] export account_system_vtimeDoug Chapman
The symbol account_system_vtime is used by the kvm module but not exported. This breaks building with CONFIG_VIRT_CPU_ACCOUNTING and CONFIG_KVM=m. Signed-off-by: Doug Chapman <doug.chapman@hp.com> Acked-by: Hidetosho Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2008-05-27[IA64] pvops: add to hooks, pv_time_ops, for steal time accounting.Isaku Yamahata
Introduce pv_time_ops which adds hook to steal time accounting. On virtualized environment, cpus are shared by many guests and steal time is the time which is used for other guests. On virtualized environtment, streal time should be accounted. Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp> Signed-off-by: Tony Luck <tony.luck@intel.com>
2008-04-30[IA64] fix section mismatch in arch/ia64/kernel/irq.cHidetoshi Seto
This patch shuts up the following: WARNING: vmlinux.o(.text+0x7102): Section mismatch in reference from the function fixup_irqs() to the function .devinit.text:ia64_disable_timer() Removing ia64_disable_timer() is safe because there are no functions calling it other than the fixup_irqs(), Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2008-02-20[IA64] VIRT_CPU_ACCOUNTING (accurate cpu time accounting)Hidetoshi Seto
This patch implements VIRT_CPU_ACCOUNTING for ia64, which enable us to use more accurate cpu time accounting. The VIRT_CPU_ACCOUNTING is an item of kernel config, which s390 and powerpc arch have. By turning this config on, these archs change the mechanism of cpu time accounting from tick-sampling based one to state-transition based one. The state-transition based accounting is done by checking time (cycle counter in processor) at every state-transition point, such as entrance/exit of kernel, interrupt, softirq etc. The difference between point to point is the actual time consumed during in the state. There is no doubt about that this value is more accurate than that of tick-sampling based accounting. Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2008-02-08time: fix typo in commentsLi Zefan
Fix typo in comments. BTW: I have to fix coding style in arch/ia64/kernel/time.c also, otherwise checkpatch.pl will be complaining. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: john stultz <johnstul@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-25sched: remove printk_clock()Ingo Molnar
printk_clock() is obsolete - it has been replaced with cpu_clock(). Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-18Fix discrepancy between VDSO based gettimeofday() and sys_gettimeofday().Tony Breeds
On platforms that copy sys_tz into the vdso (currently only x86_64, soon to include powerpc), it is possible for the vdso to get out of sync if a user calls (admittedly unusual) settimeofday(NULL, ptr). This patch adds a hook for architectures that set CONFIG_GENERIC_TIME_VSYSCALL to ensure when sys_tz is updated they can also updatee their copy in the vdso. Signed-off-by: Tony Breeds <tony@bakeyournoodle.com> Cc: Andi Kleen <ak@suse.de> Cc: Tony Luck <tony.luck@intel.com> Acked-by: John Stultz <johnstul@us.ibm.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-08-01[IA64] ITC: Reduce rating for ITC clock if ITCs are driftyChristoph Lameter
Make sure to reduce the rating of the ITC clock if ITCs are drifty. If they are drifting then we have not synchronized the ITC values, nor are we doing the jitter compensation (useless since drift may increase the differentials arbitrarily). Without this patch it is possible that the ITC clock becomes selected as the system clock on systems with drifty ITCs which will result in nanosleep hanging. One can still select the itc clock manually on such systems via clocksource=itc (Produces nice hangs on SGI Altix.) Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2007-07-26use CLOCKSOURCE_MASK() instead of too large constantAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-26ia64 time.c: ANSIfyAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-20[IA64] Convert to generic timekeeping/clocksourceTony Luck
This is a merge of Peter Keilty's initial patch (which was revived by Bob Picco) for this with Hidetoshi Seto's fixes and scaling improvements. Acked-by: Bob Picco <bob.picco@hp.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2007-06-26[IA64] remove duplicate header include lineMUNEDA Takahiro
Remove duplicate header include line from arch/ia64/kernel/time.c. Signed-off-by: MUNEDA Takahiro <muneda.takahiro@jp.fujitsu.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2007-05-08Add IRQF_IRQPOLL flag on IA64Bernhard Walle
Add IRQF_IRQPOLL for the timer interrupt on IA64. Signed-off-by: Bernhard Walle <bwalle@suse.de> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-10-17[IA64] - Allow IPIs in timer loopJack Steiner
Allow pending IPIs to interrupt a timer interrupt that is looping in the do_timer() "while" loop in timer_interrupt(). (Interrupts are allowed at only 1 spot in the code). Signed-off-by: Jack Steiner <steiner@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-10-05IRQ: Maintain regs pointer globally rather than passing to IRQ handlersDavid Howells
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: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-01[PATCH] kill wall_jiffiesAtsushi Nemoto
With 2.6.18-rc4-mm2, now wall_jiffies will always be the same as jiffies. So we can kill wall_jiffies completely. This is just a cleanup and logically should not change any real behavior except for one thing: RTC updating code in (old) ppc and xtensa use a condition "jiffies - wall_jiffies == 1". This condition is never met so I suppose it is just a bug. I just remove that condition only instead of kill the whole "if" block. [heiko.carstens@de.ibm.com: s390 build fix and cleanup] Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Cc: Andi Kleen <ak@muc.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ian Molton <spyro@f2s.com> Cc: Mikael Starvik <starvik@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Hirokazu Takata <takata.hirokazu@renesas.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp> Cc: Richard Curnow <rc@rc0.org.uk> Cc: William Lee Irwin III <wli@holomorphy.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp> Cc: Chris Zankel <chris@zankel.net> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29[PATCH] simplify update_times (avoid jiffies/jiffies_64 aliasing problem)Atsushi Nemoto
Pass ticks to do_timer() and update_times(), and adjust x86_64 and s390 timer interrupt handler with this change. Currently update_times() calculates ticks by "jiffies - wall_jiffies", but callers of do_timer() should know how many ticks to update. Passing ticks get rid of this redundant calculation. Also there are another redundancy pointed out by Martin Schwidefsky. This cleanup make a barrier added by 5aee405c662ca644980c184774277fc6d0769a84 needless. So this patch removes it. As a bonus, this cleanup make wall_jiffies can be removed easily, since now wall_jiffies is always synced with jiffies. (This patch does not really remove wall_jiffies. It would be another cleanup patch) Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: john stultz <johnstul@us.ibm.com> Cc: Andi Kleen <ak@muc.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Acked-by: Russell King <rmk@arm.linux.org.uk> Cc: Ian Molton <spyro@f2s.com> Cc: Mikael Starvik <starvik@axis.com> Acked-by: David Howells <dhowells@redhat.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Hirokazu Takata <takata.hirokazu@renesas.com> Acked-by: Ralf Baechle <ralf@linux-mips.org> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp> Cc: Richard Curnow <rc@rc0.org.uk> Cc: William Lee Irwin III <wli@holomorphy.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp> Cc: Chris Zankel <chris@zankel.net> Acked-by: "Luck, Tony" <tony.luck@intel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-02[PATCH] irq-flags: IA64: Use the new IRQF_ constantsThomas Gleixner
Use the new IRQF_ constants and remove the SA_INTERRUPT define Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "David S. Miller" <davem@davemloft.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30Remove obsolete #include <linux/config.h>Jörn Engel
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-03-31[IA64] Avoid "u64 foo : 32;" for gcc3 vs. gcc4 compatibilityTony Luck
gcc3 thinks that a 32-bit field of a u64 type is itself a u64, so should be printed with "%ld". gcc4 thinks it needs just "%d". Make both versions happy by avoiding this construct. Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-03-21Pull bsp-removal into release branchTony Luck
2006-02-15[IA64] ia64: simplify and fix udelay()hawkes@sgi.com
The original ia64 udelay() was simple, but flawed for platforms without synchronized ITCs: a preemption and migration to another CPU during the while-loop likely resulted in too-early termination or very, very lengthy looping. The first fix (now in 2.6.15) broke the delay loop into smaller, non-preemptible chunks, reenabling preemption between the chunks. This fix is flawed in that the total udelay is computed to be the sum of just the non-premptible while-loop pieces, i.e., not counting the time spent in the interim preemptible periods. If an interrupt or a migration occurs during one of these interim periods, then that time is invisible and only serves to lengthen the effective udelay(). This new fix backs out the current flawed fix and returns to a simple udelay(), fully preemptible and interruptible. It implements two simple alternative udelay() routines: one a default generic version that uses ia64_get_itc(), and the other an sn-specific version that uses that platform's RTC. Signed-off-by: John Hawkes <hawkes@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-02-07[IA64] Fix CONFIG_PRINTK_TIMETony Luck
There were two problems with enabling the PRINTK_TIME config option: 1) The first calls to printk() occur before per-cpu data virtual address is pinned into the TLB, so sched_clock() can fault. 2) sched_clock() is based on ar.itc, which may not be synchronized across cpus. Ken Chen started this patch, Tony Luck tinkered with it, and Jes Sorensen perfected it. Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-01-05[IA64] support for cpu0 removalAshok Raj
here is the BSP removal support for IA64. Its pretty much the same thing that was released a while back, but has your feedback incorporated. - Removed CONFIG_BSP_REMOVE_WORKAROUND and associated cmdline param - Fixed compile issue with sn2/zx1 due to a undefined fix_b0_for_bsp - some formatting nits (whitespace etc) This has been tested on tiger and long back by alex on hp systems as well. Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-12-16[IA64] disable preemption in udelay()John Hawkes
The udelay() inline for ia64 uses the ITC. If CONFIG_PREEMPT is enabled and the platform has unsynchronized ITCs and the calling task migrates to another CPU while doing the udelay loop, then the effective delay may be too short or very, very long. This patch disables preemption around 100 usec chunks of the overall desired udelay time. This minimizes preemption-holdoffs. udelay() is now too big to be inline, move it out of line and export it. Signed-off-by: John Hawkes <hawkes@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-10-30[PATCH] jiffies_64 cleanupThomas Gleixner
Define jiffies_64 in kernel/timer.c rather than having 24 duplicated defines in each architecture. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!