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2008-06-06uml: deal with host time going backwardsJeff Dike
Protection against the host's time going backwards (eg, ntp activity on the host) by keeping track of the time at the last tick and if it's greater than the current time, keep time stopped until the host catches up. Cc: Nix <nix@esperi.org.uk> Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-13uml: track and make up lost ticksJeff Dike
Alarm delivery could be noticably late in the !CONFIG_NOHZ case because lost ticks weren't being taken into account. This is now treated more carefully, with the time between ticks being calculated and the appropriate number of ticks delivered to the timekeeping system. Cc: Nix <nix@esperi.org.uk> Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-03uml: after_sleep_interval should return somethingJeff Dike
I forgot to have an int-returning function actually return something. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-29uml: fix !NO_HZ busy-loopJeff Dike
With NO_HZ disabled, the UML idle loop effectively becomes a busy loop, as it will sleep for no time. The cause was forgetting to restart the tick after waking up from sleep. It was disabled before sleeping, and the remaining time used as the interval to sleep. So, the tick needs to be restarted when nanosleep finishes. This is done by introducing after_sleep_interval, which is empty in the NO_HZ case, but which sets the tick starting in the !NO_HZ case. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16uml: use *SEC_PER_*SEC constantsJeff Dike
There are various uses of powers of 1000, plus the odd BILLION constant in the time code. However, there are perfectly good definitions of *SEC_PER_*SEC in linux/time.h which can be used instaed. These are replaced directly in kernel code. Userspace code imports those constants as UM_*SEC_PER_*SEC and uses these. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16uml: time build fixJeff Dike
Put back an implementation of timeval_to_ns in arch/um/os-Linux/time.c. tglx pointed out in his review of tickless support that there was a perfectly good implementation of it in linux/time.h. The problem is that this is userspace code which can't pull in kernel headers and there doesn't seem to be a libc version. So, I'm copying the version from linux/time.h rather than resurrecting my version. This causes some declaration changes as it now returns a signed value rather than an unsigned value. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16uml: eliminate interrupts in the idle loopJeff Dike
Now, the idle loop now longer needs SIGALRM firing - it can just sleep for the requisite amount of time and fake a timer interrupt when it finishes. Any use of ITIMER_REAL now goes away. disable_timer only turns off ITIMER_VIRTUAL. switch_timers is no longer needed, so it, and all calls, goes away. disable_timer now returns the amount of time remaining on the timer. default_idle uses this to tell idle_sleep how long to sleep. idle_sleep will call alarm_handler if nanosleep returns 0, which is the case if it didn't return early due to an interrupt. Otherwise, it just returns. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16uml: tickless supportJeff Dike
Enable tickless support. CONFIG_TICK_ONESHOT and CONFIG_NO_HZ are enabled. itimer_clockevent gets CLOCK_EVT_FEAT_ONESHOT and an implementation of .set_next_event. CONFIG_UML_REAL_TIME_CLOCK goes away because it only makes sense when there is a clock ticking away all the time. timer_handler now just calls do_IRQ once without trying to figure out how many ticks to emulate. The idle loop now needs to turn ticking on and off. Userspace ticks keep happening as usual. However, the userspace loop keep track of when the next wakeup should happen and suppresses process ticks until that happens. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16uml: GENERIC_CLOCKEVENTS supportJeff Dike
Enable CONFIG_GENERIC_CLOCKEVENTS. timer_irq gets its name changed to timer_handler, and becomes the recipient of timer signals. The clock_event_device is set up to imitate the current ticking clock, i.e. CLOCK_EVT_FEAT_ONESHOT is not enabled yet. disable_timer now doesn't ignore SIGALRM and SIGVTALRM because that breaks delay calibration. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16uml: simplify interval settingJeff Dike
set_interval took a timer type as an argument, but it always specified a virtual timer. So, it is not needed, and it is gone, and set_interval is simplified appropriately. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16uml: fix timer switchingJeff Dike
Fix up the switching between virtual and real timers. The idle loop sleeps, so the timer at that point must be real time. At all other times, the timer must be virtual. Even when userspace is running, and the kernel is asleep, the virtual timer is correct because the process timer will be running and the process timer will be firing. The timer switch used to be in the context switch and timer handler code. This is moved to the idle loop and the signal handler, making it much more clear why it is happening. switch_timers now returns the old timer type so that it may be restored. The signal handler uses this in order to restore the previous timer type when it returns. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16uml: eliminate hz()Jeff Dike
Eliminate hz() since its only purpose was to provide a kernel-space constant to userspace code. This can be done instead by providing the constant directly through kernel_constants.h. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16uml: style fixes pass 1Jeff Dike
Formatting changes in the files which have been changed in the tt-removal patchset so far. These include: copyright updates header file trimming style fixes adding severity to printks indenting Kconfig help according to the predominant kernel style These changes should be entirely non-functional. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16uml: throw out CONFIG_MODE_TTJeff Dike
This patchset throws out tt mode, which has been non-functional for a while. This is done in phases, interspersed with code cleanups on the affected files. The removal is done as follows: remove all code, config options, and files which depend on CONFIG_MODE_TT get rid of the CHOOSE_MODE macro, which decided whether to call tt-mode or skas-mode code, and replace invocations with their skas portions replace all now-trivial procedures with their skas equivalents There are now a bunch of now-redundant pieces of data structures, including mode-specific pieces of the thread structure, pt_regs, and mm_context. These are all replaced with their skas-specific contents. As part of the ongoing style compliance project, I made a style pass over all files that were changed. There are three such patches, one for each phase, covering the files affected by that phase but no later ones. I noticed that we weren't freeing the LDT state associated with a process when it exited, so that's fixed in one of the later patches. The last patch is a tidying patch which I've had for a while, but which caused inexplicable crashes under tt mode. Since that is no longer a problem, this can now go in. This patch: Start getting rid of tt mode support. This patch throws out CONFIG_MODE_TT and all config options, code, and files which depend on it. CONFIG_MODE_SKAS is gone and everything that depends on it is included unconditionally. The few changed lines are in re-written Kconfig help, lines which needed something skas-related removed from them, and a few more which weren't strictly deletions. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-07uml: remove user_util.hJeff Dike
user_util.h isn't needed any more, so delete it and remove all includes of it. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-10-20[PATCH] uml: reenable compilation of enable_timer, disabled by mistakePaolo 'Blaisorblade' Giarrusso
CONFIG_MODE_TT does not work there, the UML_ prefixed version must be used - this causes a link-time failure when CONFIG_MODE_TT is enabled (i.e. always here, never by Jeff). Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] uml: timer cleanupsJeff Dike
set_interval returns an error instead of panicing if setitimer fails. Some of its callers now check the return. enable_timer is largely tt-mode-specific, so it is marked as such, and the only skas-mode caller is made to call set-interval instead. user_time_init was a no-value-added wrapper around set_interval, so it is gone. Since set_interval is now called from kernel code, callers no longer pass ITIMER_* to it. Instead, they pass a flag which is converted into ITIMER_REAL or ITIMER_VIRTUAL. Signed-off-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] uml: Move signal handlers to arch codeJeff Dike
Have most signals go through an arch-provided handler which recovers the sigcontext and then calls a generic handler. This replaces the ARCH_GET_SIGCONTEXT macro, which was somewhat fragile. On x86_64, recovering %rdx (which holds the sigcontext pointer) must be the first thing that happens. sig_handler duly invokes that first, but there is no guarantee that I can see that instructions won't be reordered such that %rdx is used before that. Having the arch provide the handler seems much more robust. Some signals in some parts of UML require their own handlers - these places don't call set_handler any more. They call sigaction or signal themselves. Signed-off-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10[PATCH] uml: ifdef a mode-specific functionJeff Dike
uml_idle_timer is tt-mode only, so ifdef it as such to make it easier to spot when tt mode is killed. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10[PATCH] uml: remove useless declarationJeff Dike
wall_to_monotonic isn't used in this file, so we can remove the declaration. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10[PATCH] uml: timer initialization cleanupJeff Dike
This cleans up the mess that is the timer initialization. There used to be two timer handlers - one that basically ran during delay loop calibration and one that handled the timer afterwards. There were also two sets of timer initialization code - one that starts in user code and calls into the kernel side of the house, and one that starts in kernel code and calls user code. This eliminates one timer handler and consolidates the two sets of initialization code. [akpm@osdl.org: use new INTF_ flags] Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-05[PATCH] uml: fix wall_to_monotonic initializationJeff Dike
From: Jeff Dike <jdike@addtoit.com> Initialize wall_to_monotonic correctly. This fixes a problem where sleeps lasted about one secone less than they should. This also called for a bit of code restructuring, following a patch which Blaisorblade had been keeping. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-18[PATCH] uml: move libc-dependent time codeGennady Sharapov
The serial UML OS-abstraction layer patch (um/kernel dir). This moves all systemcalls from time.c file under os-Linux dir and joins time.c and tine_kernel.c files Signed-off-by: Gennady Sharapov <Gennady.V.Sharapov@intel.com> Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> 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!