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2008-02-08clocksource: remove redundant codeLi Zefan
Flag CLOCK_SOURCE_WATCHDOG is cleared twice. Note clocksource_change_rating() won't do anyting with the cs flag. 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>
2008-02-06time: fix sysfs_show_{available,current}_clocksources() buffer overflow problemMiao Xie
I found that there is a buffer overflow problem in the following code. Version: 2.6.24-rc2, File: kernel/time/clocksource.c:417-432 -------------------------------------------------------------------- static ssize_t sysfs_show_available_clocksources(struct sys_device *dev, char *buf) { struct clocksource *src; char *curr = buf; spin_lock_irq(&clocksource_lock); list_for_each_entry(src, &clocksource_list, list) { curr += sprintf(curr, "%s ", src->name); } spin_unlock_irq(&clocksource_lock); curr += sprintf(curr, "\n"); return curr - buf; } ----------------------------------------------------------------------- sysfs_show_current_clocksources() also has the same problem though in practice the size of current clocksource's name won't exceed PAGE_SIZE. I fix the bug by using snprintf according to the specification of the kernel (Version:2.6.24-rc2,File:Documentation/filesystems/sysfs.txt) Fix sysfs_show_available_clocksources() and sysfs_show_current_clocksources() buffer overflow problem with snprintf(). Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Cc: WANG Cong <xiyou.wangcong@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> 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>
2008-01-30clocksource: add unregister function to disable unusable clocksourcesThomas Gleixner
On x86 the PIT might become an unusable clocksource. Add an unregister function to provide a possibilty to remove the PIT from the list of available clock sources. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-01-30clocksource: make clocksource watchdog cycle through online CPUsAndi Kleen
This way it checks if the clocks are synchronized between CPUs too. This might be able to detect slowly drifting TSCs which only go wrong over longer time. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30clocksource.c: use init_timer_deferrable for clocksource_watchdogParag Warudkar
clocksource_watchdog can use a deferrable timer - reduces wakeups from idle per second. Signed-off-by: Parag Warudkar <parag.warudkar@gmail.com> Cc: john stultz <johnstul@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-24Driver core: change sysdev classes to use dynamic kobject namesKay Sievers
All kobjects require a dynamically allocated name now. We no longer need to keep track if the name is statically assigned, we can just unconditionally free() all kobject names on cleanup. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-19kernel/time/clocksource.c: Use list_for_each_entry instead of list_for_eachMatthias Kaehlcke
kernel/time/clocksource.c: Convert list_for_each to list_for_each_entry in clocksource_resume(), sysfs_override_clocksource() and show_available_clocksources() Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> 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>
2007-05-15clocksource: fix lock order in the resume pathThomas Gleixner
lockdep complains about the lock nesting of clocksource and watchdog lock in the resume path. Change the resume marker to a bit operation and remove the lock from this path. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> 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>
2007-05-09clocksource: fix resume logicThomas Gleixner
We need to make sure that the clocksources are resumed, when timekeeping is resumed. The current resume logic does not guarantee this. Add a resume function pointer to the clocksource struct, so clocksource drivers which need to reinitialize the clocksource can provide a resume function. Add a resume function, which calls the maybe available clocksource resume functions and resets the watchdog function, so a stable TSC can be used accross suspend/resume. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Andi Kleen <ak@suse.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-09clocksource: spelling error in watchdog codeDaniel Walker
There's more that need fixing, and fix my own subject spelling error too. Signed-off-by: Daniel Walker <dwalker@mvista.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-25[PATCH] clocksource: Fix thinko in watchdog selectionThomas Gleixner
The watchdog implementation excludes low res / non continuous clocksources from being selected as a watchdog reference unintentionally. Allow using jiffies/PIT as a watchdog reference as long as no better clocksource is available. This is necessary to detect TSC breakage on systems, which have no pmtimer/hpet. The main goal of the initial patch (preventing to switch to highres/nohz when no reliable fallback clocksource is available) is still guaranteed by the checks in clocksource_watchdog(). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-05[PATCH] clocksource init adjustments (fix bug #7426)john stultz
This patch resolves the issue found here: http://bugme.osdl.org/show_bug.cgi?id=7426 The basic summary is: Currently we register most of i386/x86_64 clocksources at module_init time. Then we enable clocksource selection at late_initcall time. This causes some problems for drivers that use gettimeofday for init calibration routines (specifically the es1968 driver in this case), where durring module_init, the only clocksource available is the low-res jiffies clocksource. This may cause slight calibration errors, due to the small sampling time used. It should be noted that drivers that require fine grained time may not function on architectures that do not have better then jiffies resolution timekeeping (there are a few). However, this does not discount the reasonable need for such fine-grained timekeeping at init time. Thus the solution here is to register clocksources earlier (ideally when the hardware is being initialized), and then we enable clocksource selection at fs_initcall (before device_initcall). This patch should probably get some testing time in -mm, since clocksource selection is one of the most important issues for correct timekeeping, and I've only been able to test this on a few of my own boxes. Signed-off-by: John Stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16[PATCH] tick-management: dyntick / highres functionalityThomas Gleixner
With Ingo Molnar <mingo@elte.hu> Add functions to provide dynamic ticks and high resolution timers. The code which keeps track of jiffies and handles the long idle periods is shared between tick based and high resolution timer based dynticks. The dyntick functionality can be disabled on the kernel commandline. Provide also the infrastructure to support high resolution timers. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16[PATCH] clocksource: Add verification (watchdog) helperThomas Gleixner
The TSC needs to be verified against another clocksource. Instead of using hardwired assumptions of available hardware, provide a generic verification mechanism. The verification uses the best available clocksource and handles the usability for high resolution timers / dynticks of the clocksource which needs to be verified. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16[PATCH] Simplify the registration of clocksourcesThomas Gleixner
Enqueue clocksources in rating order to make selection of the clocksource easier. Also check the match with an user override at enqueue time. Preparatory patch for the generic clocksource verification. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] kernel/time/clocksource.c needs struct task_struct on m68kMathieu Desnoyers
kernel/time/clocksource.c needs struct task_struct on m68k. Because it uses spin_unlock_irq(), which, on m68k, uses hardirq_count(), which uses preempt_count(), which needs to dereference struct task_struct, we have to include sched.h. Because it would cause a loop inclusion, we cannot include sched.h in any other of asm-m68k/system.h, linux/thread_info.h, linux/hardirq.h, which leaves this ugly include in a C file as the only simple solution. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: Ingo Molnar <mingo@elte.hu> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-12-10[PATCH] clocksource: small cleanupDaniel Walker
Mostly changing alignment. Just some general cleanup. [akpm@osdl.org: build fix] Signed-off-by: Daniel Walker <dwalker@mvista.com> Acked-by: John Stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-10[PATCH] clocksource: add usage of CONFIG_SYSFSDaniel Walker
Simply adds some ifdefs to remove clocksoure sysfs code when CONFIG_SYSFS isn't turn on. Signed-off-by: Daniel Walker <dwalker@mvista.com> Acked-by: John Stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] time: rename clocksource functionsjohn stultz
As suggested by Roman Zippel, change clocksource functions to use clocksource_xyz rather then xyz_clocksource to avoid polluting the namespace. Signed-off-by: John Stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] Time: i386 Clocksource Driversjohn stultz
Implement the time sources for i386 (acpi_pm, cyclone, hpet, pit, and tsc). With this patch, the conversion of the i386 arch to the generic timekeeping code should be complete. The patch should be fairly straight forward, only adding the new clocksources. [hirofumi@mail.parknet.co.jp: acpi_pm cleanup] Signed-off-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Paul Mundt <lethal@linux-sh.org> Signed-off-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] Time: Use clocksource infrastructure for update_wall_timejohn stultz
Modify the update_wall_time function so it increments time using the clocksource abstraction instead of jiffies. Since the only clocksource driver currently provided is the jiffies clocksource, this should result in no functional change. Additionally, a timekeeping_init and timekeeping_resume function has been added to initialize and maintain some of the new timekeping state. [hirofumi@mail.parknet.co.jp: fixlet] Signed-off-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] Time: Clocksource Infrastructurejohn stultz
This introduces the clocksource management infrastructure. A clocksource is a driver-like architecture generic abstraction of a free-running counter. This code defines the clocksource structure, and provides management code for registering, selecting, accessing and scaling clocksources. Additionally, this includes the trivial jiffies clocksource, a lowest common denominator clocksource, provided mainly for use as an example. [hirofumi@mail.parknet.co.jp: Don't enable IRQ too early] Signed-off-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Paul Mundt <lethal@linux-sh.org> Signed-off-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>