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* clocksource: Move inline keyword to the beginning of function declarationsMathieu Malaterre2019-06-141-2/+2
| | | | | | | | | | | | | | | | | The inline keyword was not at the beginning of the function declarations. Fix the following warnings triggered when using W=1: kernel/time/clocksource.c:108:1: warning: 'inline' is not at beginning of declaration [-Wold-style-declaration] kernel/time/clocksource.c:113:1: warning: 'inline' is not at beginning of declaration [-Wold-style-declaration] Signed-off-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: trivial@kernel.org Cc: kernel-janitors@vger.kernel.org Cc: John Stultz <john.stultz@linaro.org> Cc: Stephen Boyd <sboyd@kernel.org> Link: https://lkml.kernel.org/r/20190524103339.28787-1-malat@debian.org
* time: Remove license boilerplateThomas Gleixner2018-11-231-14/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | | The SPDX identifier defines the license of the files already. No need for the boilerplates. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: John Stultz <john.stultz@linaro.org> Acked-by: Corey Minyard <cminyard@mvista.com> Acked-by: Paul E. McKenney <paulmck@linux.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Russell King <rmk+kernel@armlinux.org.uk> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Nicolas Pitre <nicolas.pitre@linaro.org> Cc: David Riley <davidriley@chromium.org> Cc: Colin Cross <ccross@android.com> Cc: Mark Brown <broonie@kernel.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Link: https://lkml.kernel.org/r/20181031182253.132458951@linutronix.de
* time: Add SPDX license identifiersThomas Gleixner2018-11-231-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Update the time(r) core files files with the correct SPDX license identifier based on the license text in the file itself. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This work is based on a script and data from Philippe Ombredanne, Kate Stewart and myself. The data has been created with two independent license scanners and manual inspection. The following files do not contain any direct license information and have been omitted from the big initial SPDX changes: timeconst.bc: The .bc files were not touched time.c, timer.c, timekeeping.c: Licence was deduced from EXPORT_SYMBOL_GPL As those files do not contain direct license references they fall under the project license, i.e. GPL V2 only. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: John Stultz <john.stultz@linaro.org> Acked-by: Corey Minyard <cminyard@mvista.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Russell King <rmk+kernel@armlinux.org.uk> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Nicolas Pitre <nicolas.pitre@linaro.org> Cc: David Riley <davidriley@chromium.org> Cc: Colin Cross <ccross@android.com> Cc: Mark Brown <broonie@kernel.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Link: https://lkml.kernel.org/r/20181031182252.879109557@linutronix.de
* time: Remove useless filenames in top level commentsThomas Gleixner2018-11-231-5/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | | Remove the pointless filenames in the top level comments. They have no value at all and just occupy space. While at it tidy up some of the comments and remove a stale one. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: John Stultz <john.stultz@linaro.org> Acked-by: Corey Minyard <cminyard@mvista.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Russell King <rmk+kernel@armlinux.org.uk> Cc: Richard Cochran <richardcochran@gmail.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: David Riley <davidriley@chromium.org> Cc: Colin Cross <ccross@android.com> Cc: Mark Brown <broonie@kernel.org> Link: https://lkml.kernel.org/r/20181031182252.794898238@linutronix.de
* clocksource: Provide clocksource_arch_init()Thomas Gleixner2018-10-041-0/+2
| | | | | | | | | | | | | | | | | | | | | | | Architectures have extra archdata in the clocksource, e.g. for VDSO support. There are no sanity checks or general initializations for this available. Add support for that. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andy Lutomirski <luto@kernel.org> Acked-by: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Matt Rickard <matt@softrans.com.au> Cc: Stephen Boyd <sboyd@kernel.org> Cc: Florian Weimer <fweimer@redhat.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: devel@linuxdriverproject.org Cc: virtualization@lists.linux-foundation.org Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Juergen Gross <jgross@suse.com> Link: https://lkml.kernel.org/r/20180917130706.973042587@linutronix.de
* clocksource: Revert "Remove kthread"Peter Zijlstra2018-09-061-10/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | I turns out that the silly spawn kthread from worker was actually needed. clocksource_watchdog_kthread() cannot be called directly from clocksource_watchdog_work(), because clocksource_select() calls timekeeping_notify() which uses stop_machine(). One cannot use stop_machine() from a workqueue() due lock inversions wrt CPU hotplug. Revert the patch but add a comment that explain why we jump through such apparently silly hoops. Fixes: 7197e77abcb6 ("clocksource: Remove kthread") Reported-by: Siegfried Metz <frame@mailbox.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Niklas Cassel <niklas.cassel@linaro.org> Tested-by: Kevin Shanahan <kevin@shanahan.id.au> Tested-by: viktor_jaegerskuepper@freenet.de Tested-by: Siegfried Metz <frame@mailbox.org> Cc: rafael.j.wysocki@intel.com Cc: len.brown@intel.com Cc: diego.viola@gmail.com Cc: rui.zhang@intel.com Cc: bjorn.andersson@linaro.org Link: https://lkml.kernel.org/r/20180905084158.GR24124@hirez.programming.kicks-ass.net
* time: Introduce one suspend clocksource to compensate the suspend timeBaolin Wang2018-07-201-0/+149
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On some hardware with multiple clocksources, we have coarse grained clocksources that support the CLOCK_SOURCE_SUSPEND_NONSTOP flag, but which are less than ideal for timekeeping whereas other clocksources can be better candidates but halt on suspend. Currently, the timekeeping core only supports timing suspend using CLOCK_SOURCE_SUSPEND_NONSTOP clocksources if that clocksource is the current clocksource for timekeeping. As a result, some architectures try to implement read_persistent_clock64() using those non-stop clocksources, but isn't really ideal, which will introduce more duplicate code. To fix this, provide logic to allow a registered SUSPEND_NONSTOP clocksource, which isn't the current clocksource, to be used to calculate the suspend time. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Miroslav Lichvar <mlichvar@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Stephen Boyd <sboyd@kernel.org> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org> Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Baolin Wang <baolin.wang@linaro.org> [jstultz: minor tweaks to merge with previous resume changes] Signed-off-by: John Stultz <john.stultz@linaro.org>
* clocksource: Move inline keyword to the beginning of function declarationsMathieu Malaterre2018-05-161-2/+2
| | | | | | | | | | | | | | | The inline keyword was not at the beginning of the function declarations. Fix the following warnings triggered when using W=1: kernel/time/clocksource.c:456:1: warning: ‘inline’ is not at beginning of declaration [-Wold-style-declaration] kernel/time/clocksource.c:457:1: warning: ‘inline’ is not at beginning of declaration [-Wold-style-declaration] Signed-off-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Stephen Boyd <sboyd@kernel.org> Cc: John Stultz <john.stultz@linaro.org> Link: https://lkml.kernel.org/r/20180516195943.31924-1-malat@debian.org
* clocksource: Remove kthreadPeter Zijlstra2018-05-021-21/+10Star
| | | | | | | | | | | | | | | | The clocksource watchdog uses a work to spawn a kthread to run the watchdog. That is about as silly as it sounds, run the watchdog directly from the work. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: len.brown@intel.com Cc: rjw@rjwysocki.net Cc: diego.viola@gmail.com Cc: rui.zhang@intel.com Link: https://lkml.kernel.org/r/20180430100344.713862818@infradead.org
* clocksource: Rework stale commentPeter Zijlstra2018-05-021-4/+2Star
| | | | | | | | | | | | | | AFAICS the hotplug code no longer uses this function. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: len.brown@intel.com Cc: rjw@rjwysocki.net Cc: diego.viola@gmail.com Cc: rui.zhang@intel.com Link: https://lkml.kernel.org/r/20180430100344.656525644@infradead.org
* clocksource: Consistent de-rate when marking unstablePeter Zijlstra2018-05-021-1/+8
| | | | | | | | | | | | | | | | | When a registered clocksource gets marked unstable the watchdog_kthread will de-rate and re-select the clocksource. Ensure it also de-rates when getting called on an unregistered clocksource. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: len.brown@intel.com Cc: rjw@rjwysocki.net Cc: diego.viola@gmail.com Cc: rui.zhang@intel.com Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180430100344.594904898@infradead.org
* clocksource: Initialize cs->wd_listPeter Zijlstra2018-05-021-0/+2
| | | | | | | | | | | | | | | | | | A number of places relies on list_empty(&cs->wd_list), however the list_head does not get initialized. Do so upon registration, such that thereafter it is possible to rely on list_empty() correctly reflecting the list membership status. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Diego Viola <diego.viola@gmail.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: stable@vger.kernel.org Cc: len.brown@intel.com Cc: rjw@rjwysocki.net Cc: rui.zhang@intel.com Link: https://lkml.kernel.org/r/20180430100344.472662715@infradead.org
* clocksource: Allow clocksource_mark_unstable() on unregistered clocksourcesPeter Zijlstra2018-05-021-16/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Because of how the code flips between tsc-early and tsc clocksources it might need to mark one or both unstable. The current code in mark_tsc_unstable() only worked because previously it registered the tsc clocksource once and then never touched it. Since it now unregisters the tsc-early clocksource, it needs to know if a clocksource got unregistered and the current cs->mult test doesn't work for that. Instead use list_empty(&cs->list) to test for registration. Furthermore, since clocksource_mark_unstable() needs to place the cs on the wd_list, it links the cs->list and cs->wd_list serialization. It must not see a clocsource registered (!empty cs->list) but already past dequeue_watchdog(). So place {en,de}queue{,_watchdog}() under the same lock. Provided cs->list is initialized to empty, this then allows us to unconditionally use clocksource_mark_unstable(), regardless of the registration state. Fixes: aa83c45762a2 ("x86/tsc: Introduce early tsc clocksource") Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Diego Viola <diego.viola@gmail.com> Cc: len.brown@intel.com Cc: rjw@rjwysocki.net Cc: diego.viola@gmail.com Cc: rui.zhang@intel.com Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180502135312.GS12217@hirez.programming.kicks-ass.net
* clocksource: Use ATTRIBUTE_GROUPSBaolin Wang2018-02-281-11/+10Star
| | | | | | | | | | | | | Use ATTRIBUTE_GROUPS instead of manually creating the individual device files. Signed-off-by: Baolin Wang <baolin.wang@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: arnd@arndb.de Cc: sboyd@codeaurora.org Cc: broonie@kernel.org Cc: john.stultz@linaro.org Link: https://lkml.kernel.org/r/d80dccb981dc2461781ebb8d71a32ccdc1b0e6f9.1516167691.git.baolin.wang@linaro.org
* clocksource: Use DEVICE_ATTR_RW/RO/WO to define device attributesBaolin Wang2018-02-281-26/+17Star
| | | | | | | | | | | | | | Convert DEVICE_ATTR to DEVICE_ATTR_RW/RO/WO which is the preferred and simpler way of implementation. Signed-off-by: Baolin Wang <baolin.wang@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: arnd@arndb.de Cc: sboyd@codeaurora.org Cc: broonie@kernel.org Cc: john.stultz@linaro.org Link: https://lkml.kernel.org/r/8f35c77e753e957b61187e8e7b2e4a3d61e4a72b.1516167691.git.baolin.wang@linaro.org
* clocksource: Don't walk the clocksource list for empty overrideBaolin Wang2018-02-281-0/+4
| | | | | | | | | | | | | | If the override clocksource name is empty there is no point in walking the clocksource list for a match. Signed-off-by: Baolin Wang <baolin.wang@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: arnd@arndb.de Cc: sboyd@codeaurora.org Cc: broonie@kernel.org Cc: john.stultz@linaro.org Link: https://lkml.kernel.org/r/069ce2a605546bcad6552968cff755f0a03f9f10.1516167691.git.baolin.wang@linaro.org
* treewide: setup_timer() -> timer_setup()Kees Cook2017-11-221-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This converts all remaining cases of the old setup_timer() API into using timer_setup(), where the callback argument is the structure already holding the struct timer_list. These should have no behavioral changes, since they just change which pointer is passed into the callback with the same available pointers after conversion. It handles the following examples, in addition to some other variations. Casting from unsigned long: void my_callback(unsigned long data) { struct something *ptr = (struct something *)data; ... } ... setup_timer(&ptr->my_timer, my_callback, ptr); and forced object casts: void my_callback(struct something *ptr) { ... } ... setup_timer(&ptr->my_timer, my_callback, (unsigned long)ptr); become: void my_callback(struct timer_list *t) { struct something *ptr = from_timer(ptr, t, my_timer); ... } ... timer_setup(&ptr->my_timer, my_callback, 0); Direct function assignments: void my_callback(unsigned long data) { struct something *ptr = (struct something *)data; ... } ... ptr->my_timer.function = my_callback; have a temporary cast added, along with converting the args: void my_callback(struct timer_list *t) { struct something *ptr = from_timer(ptr, t, my_timer); ... } ... ptr->my_timer.function = (TIMER_FUNC_TYPE)my_callback; And finally, callbacks without a data assignment: void my_callback(unsigned long data) { ... } ... setup_timer(&ptr->my_timer, my_callback, 0); have their argument renamed to verify they're unused during conversion: void my_callback(struct timer_list *unused) { ... } ... timer_setup(&ptr->my_timer, my_callback, 0); The conversion is done with the following Coccinelle script: spatch --very-quiet --all-includes --include-headers \ -I ./arch/x86/include -I ./arch/x86/include/generated \ -I ./include -I ./arch/x86/include/uapi \ -I ./arch/x86/include/generated/uapi -I ./include/uapi \ -I ./include/generated/uapi --include ./include/linux/kconfig.h \ --dir . \ --cocci-file ~/src/data/timer_setup.cocci @fix_address_of@ expression e; @@ setup_timer( -&(e) +&e , ...) // Update any raw setup_timer() usages that have a NULL callback, but // would otherwise match change_timer_function_usage, since the latter // will update all function assignments done in the face of a NULL // function initialization in setup_timer(). @change_timer_function_usage_NULL@ expression _E; identifier _timer; type _cast_data; @@ ( -setup_timer(&_E->_timer, NULL, _E); +timer_setup(&_E->_timer, NULL, 0); | -setup_timer(&_E->_timer, NULL, (_cast_data)_E); +timer_setup(&_E->_timer, NULL, 0); | -setup_timer(&_E._timer, NULL, &_E); +timer_setup(&_E._timer, NULL, 0); | -setup_timer(&_E._timer, NULL, (_cast_data)&_E); +timer_setup(&_E._timer, NULL, 0); ) @change_timer_function_usage@ expression _E; identifier _timer; struct timer_list _stl; identifier _callback; type _cast_func, _cast_data; @@ ( -setup_timer(&_E->_timer, _callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, &_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, &_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)&_callback, _E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, (_cast_func)&_callback, (_cast_data)_E); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E._timer, _callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, &_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, &_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)_E); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, (_cast_func)&_callback, (_cast_data)&_E); +timer_setup(&_E._timer, _callback, 0); | _E->_timer@_stl.function = _callback; | _E->_timer@_stl.function = &_callback; | _E->_timer@_stl.function = (_cast_func)_callback; | _E->_timer@_stl.function = (_cast_func)&_callback; | _E._timer@_stl.function = _callback; | _E._timer@_stl.function = &_callback; | _E._timer@_stl.function = (_cast_func)_callback; | _E._timer@_stl.function = (_cast_func)&_callback; ) // callback(unsigned long arg) @change_callback_handle_cast depends on change_timer_function_usage@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _origtype; identifier _origarg; type _handletype; identifier _handle; @@ void _callback( -_origtype _origarg +struct timer_list *t ) { ( ... when != _origarg _handletype *_handle = -(_handletype *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle = -(void *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle; ... when != _handle _handle = -(_handletype *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg | ... when != _origarg _handletype *_handle; ... when != _handle _handle = -(void *)_origarg; +from_timer(_handle, t, _timer); ... when != _origarg ) } // callback(unsigned long arg) without existing variable @change_callback_handle_cast_no_arg depends on change_timer_function_usage && !change_callback_handle_cast@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _origtype; identifier _origarg; type _handletype; @@ void _callback( -_origtype _origarg +struct timer_list *t ) { + _handletype *_origarg = from_timer(_origarg, t, _timer); + ... when != _origarg - (_handletype *)_origarg + _origarg ... when != _origarg } // Avoid already converted callbacks. @match_callback_converted depends on change_timer_function_usage && !change_callback_handle_cast && !change_callback_handle_cast_no_arg@ identifier change_timer_function_usage._callback; identifier t; @@ void _callback(struct timer_list *t) { ... } // callback(struct something *handle) @change_callback_handle_arg depends on change_timer_function_usage && !match_callback_converted && !change_callback_handle_cast && !change_callback_handle_cast_no_arg@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _handletype; identifier _handle; @@ void _callback( -_handletype *_handle +struct timer_list *t ) { + _handletype *_handle = from_timer(_handle, t, _timer); ... } // If change_callback_handle_arg ran on an empty function, remove // the added handler. @unchange_callback_handle_arg depends on change_timer_function_usage && change_callback_handle_arg@ identifier change_timer_function_usage._callback; identifier change_timer_function_usage._timer; type _handletype; identifier _handle; identifier t; @@ void _callback(struct timer_list *t) { - _handletype *_handle = from_timer(_handle, t, _timer); } // We only want to refactor the setup_timer() data argument if we've found // the matching callback. This undoes changes in change_timer_function_usage. @unchange_timer_function_usage depends on change_timer_function_usage && !change_callback_handle_cast && !change_callback_handle_cast_no_arg && !change_callback_handle_arg@ expression change_timer_function_usage._E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type change_timer_function_usage._cast_data; @@ ( -timer_setup(&_E->_timer, _callback, 0); +setup_timer(&_E->_timer, _callback, (_cast_data)_E); | -timer_setup(&_E._timer, _callback, 0); +setup_timer(&_E._timer, _callback, (_cast_data)&_E); ) // If we fixed a callback from a .function assignment, fix the // assignment cast now. @change_timer_function_assignment depends on change_timer_function_usage && (change_callback_handle_cast || change_callback_handle_cast_no_arg || change_callback_handle_arg)@ expression change_timer_function_usage._E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type _cast_func; typedef TIMER_FUNC_TYPE; @@ ( _E->_timer.function = -_callback +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -&_callback +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -(_cast_func)_callback; +(TIMER_FUNC_TYPE)_callback ; | _E->_timer.function = -(_cast_func)&_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -&_callback; +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -(_cast_func)_callback +(TIMER_FUNC_TYPE)_callback ; | _E._timer.function = -(_cast_func)&_callback +(TIMER_FUNC_TYPE)_callback ; ) // Sometimes timer functions are called directly. Replace matched args. @change_timer_function_calls depends on change_timer_function_usage && (change_callback_handle_cast || change_callback_handle_cast_no_arg || change_callback_handle_arg)@ expression _E; identifier change_timer_function_usage._timer; identifier change_timer_function_usage._callback; type _cast_data; @@ _callback( ( -(_cast_data)_E +&_E->_timer | -(_cast_data)&_E +&_E._timer | -_E +&_E->_timer ) ) // If a timer has been configured without a data argument, it can be // converted without regard to the callback argument, since it is unused. @match_timer_function_unused_data@ expression _E; identifier _timer; identifier _callback; @@ ( -setup_timer(&_E->_timer, _callback, 0); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, 0L); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E->_timer, _callback, 0UL); +timer_setup(&_E->_timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0L); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_E._timer, _callback, 0UL); +timer_setup(&_E._timer, _callback, 0); | -setup_timer(&_timer, _callback, 0); +timer_setup(&_timer, _callback, 0); | -setup_timer(&_timer, _callback, 0L); +timer_setup(&_timer, _callback, 0); | -setup_timer(&_timer, _callback, 0UL); +timer_setup(&_timer, _callback, 0); | -setup_timer(_timer, _callback, 0); +timer_setup(_timer, _callback, 0); | -setup_timer(_timer, _callback, 0L); +timer_setup(_timer, _callback, 0); | -setup_timer(_timer, _callback, 0UL); +timer_setup(_timer, _callback, 0); ) @change_callback_unused_data depends on match_timer_function_unused_data@ identifier match_timer_function_unused_data._callback; type _origtype; identifier _origarg; @@ void _callback( -_origtype _origarg +struct timer_list *unused ) { ... when != _origarg } Signed-off-by: Kees Cook <keescook@chromium.org>
* treewide: init_timer() -> setup_timer()Kees Cook2017-11-221-2/+1Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This mechanically converts all remaining cases of ancient open-coded timer setup with the old setup_timer() API, which is the first step in timer conversions. This has no behavioral changes, since it ultimately just changes the order of assignment to fields of struct timer_list when finding variations of: init_timer(&t); f.function = timer_callback; t.data = timer_callback_arg; to be converted into: setup_timer(&t, timer_callback, timer_callback_arg); The conversion is done with the following Coccinelle script, which is an improved version of scripts/cocci/api/setup_timer.cocci, in the following ways: - assignments-before-init_timer() cases - limit the .data case removal to the specific struct timer_list instance - handling calls by dereference (timer->field vs timer.field) spatch --very-quiet --all-includes --include-headers \ -I ./arch/x86/include -I ./arch/x86/include/generated \ -I ./include -I ./arch/x86/include/uapi \ -I ./arch/x86/include/generated/uapi -I ./include/uapi \ -I ./include/generated/uapi --include ./include/linux/kconfig.h \ --dir . \ --cocci-file ~/src/data/setup_timer.cocci @fix_address_of@ expression e; @@ init_timer( -&(e) +&e , ...) // Match the common cases first to avoid Coccinelle parsing loops with // "... when" clauses. @match_immediate_function_data_after_init_timer@ expression e, func, da; @@ -init_timer +setup_timer ( \(&e\|e\) +, func, da ); ( -\(e.function\|e->function\) = func; -\(e.data\|e->data\) = da; | -\(e.data\|e->data\) = da; -\(e.function\|e->function\) = func; ) @match_immediate_function_data_before_init_timer@ expression e, func, da; @@ ( -\(e.function\|e->function\) = func; -\(e.data\|e->data\) = da; | -\(e.data\|e->data\) = da; -\(e.function\|e->function\) = func; ) -init_timer +setup_timer ( \(&e\|e\) +, func, da ); @match_function_and_data_after_init_timer@ expression e, e2, e3, e4, e5, func, da; @@ -init_timer +setup_timer ( \(&e\|e\) +, func, da ); ... when != func = e2 when != da = e3 ( -e.function = func; ... when != da = e4 -e.data = da; | -e->function = func; ... when != da = e4 -e->data = da; | -e.data = da; ... when != func = e5 -e.function = func; | -e->data = da; ... when != func = e5 -e->function = func; ) @match_function_and_data_before_init_timer@ expression e, e2, e3, e4, e5, func, da; @@ ( -e.function = func; ... when != da = e4 -e.data = da; | -e->function = func; ... when != da = e4 -e->data = da; | -e.data = da; ... when != func = e5 -e.function = func; | -e->data = da; ... when != func = e5 -e->function = func; ) ... when != func = e2 when != da = e3 -init_timer +setup_timer ( \(&e\|e\) +, func, da ); @r1 exists@ expression t; identifier f; position p; @@ f(...) { ... when any init_timer@p(\(&t\|t\)) ... when any } @r2 exists@ expression r1.t; identifier g != r1.f; expression e8; @@ g(...) { ... when any \(t.data\|t->data\) = e8 ... when any } // It is dangerous to use setup_timer if data field is initialized // in another function. @script:python depends on r2@ p << r1.p; @@ cocci.include_match(False) @r3@ expression r1.t, func, e7; position r1.p; @@ ( -init_timer@p(&t); +setup_timer(&t, func, 0UL); ... when != func = e7 -t.function = func; | -t.function = func; ... when != func = e7 -init_timer@p(&t); +setup_timer(&t, func, 0UL); | -init_timer@p(t); +setup_timer(t, func, 0UL); ... when != func = e7 -t->function = func; | -t->function = func; ... when != func = e7 -init_timer@p(t); +setup_timer(t, func, 0UL); ) Signed-off-by: Kees Cook <keescook@chromium.org>
* x86/tsc, sched/clock, clocksource: Use clocksource watchdog to provide ↵Peter Zijlstra2017-05-151-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | stable sync points Currently we keep sched_clock_tick() active for stable TSC in order to keep the per-CPU state semi up-to-date. The (obvious) problem is that by the time we detect TSC is borked, our per-CPU state is also borked. So hook into the clocksource watchdog and call a method after we've found it to still be stable. There's the obvious race where the TSC goes wonky between finding it stable and us running the callback, but closing that is too much work and not really worth it, since we're already detecting TSC wobbles after the fact, so we cannot, per definition, fully avoid funny clock values. And since the watchdog runs less often than the tick, this is also an optimization. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* sched/clock, clocksource: Add optional cs::mark_unstable() methodThomas Gleixner2017-01-141-0/+4
| | | | | | | | | | | | | | | | | PeterZ reported that we'd fail to mark the TSC unstable when the clocksource watchdog finds it unsuitable. Allow a clocksource to run a custom action when its being marked unstable and hook up the TSC unstable code. Reported-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* clocksource: Use a plain u64 instead of cycle_tThomas Gleixner2016-12-251-1/+1
| | | | | | | | | | | | | | | | | | | | | There is no point in having an extra type for extra confusion. u64 is unambiguous. Conversion was done with the following coccinelle script: @rem@ @@ -typedef u64 cycle_t; @fix@ typedef cycle_t; @@ -cycle_t +u64 Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org>
* clocksource: export the clocks_calc_mult_shift to use by timestamp codeMurali Karicheri2016-12-071-0/+1
| | | | | | | | | | | | | | | | | | The CPSW CPTS driver is capable of doing timestamping on tx/rx packets and requires to know mult and shift factors for timestamp conversion from raw value to nanoseconds (ptp clock). Now these mult and shift factors are calculated manually and provided through DT, which makes very hard to support of a lot number of platforms, especially if CPTS refclk is not the same for some kind of boards and depends on efuse settings (Keystone 2 platforms). Hence, export clocks_calc_mult_shift() to allow drivers like CPSW CPTS (and other ptp drivesr) to benefit from automaitc calculation of mult and shift factors. Cc: John Stultz <john.stultz@linaro.org> Signed-off-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* clocksource: Defer override invalidation unless clock is unstableKyle Walker2016-08-311-3/+12
| | | | | | | | | | | | | | | | | | | | | | Clocksources don't get the VALID_FOR_HRES flag until they have been checked by a watchdog. However, when using an override, the clocksource_select logic will clear the override value if the clocksource is not marked VALID_FOR_HRES during that inititial check. When using the boot arguments clocksource=<foo>, this selection can run before the watchdog, and can cause the override to be incorrectly cleared. To address this condition, the override_name is only invalidated for unstable clocksources. Otherwise, the override is left intact until after the watchdog has validated the clocksource as stable/unstable. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Kyle Walker <kwalker@redhat.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
* clocksource: Make clocksource insert entry more efficientMinfei Huang2016-06-201-3/+5
| | | | | | | | | | | | | | In clocksource_enqueue(), it is unnecessary to continue looping the list, if we find there is an entry that the value of rating is smaller than the new one. It is safe to be out the loop, because all of entry are inserted in descending order. Cc: Prarit Bhargava <prarit@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Minfei Huang <mnghuan@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
* clocksource: Allow unregistering the watchdogVitaly Kuznetsov2016-01-271-10/+42
| | | | | | | | | | | | | | | | | Hyper-V vmbus module registers TSC page clocksource when loaded. This is the clocksource with the highest rating and thus it becomes the watchdog making unloading of the vmbus module impossible. Separate clocksource_select_watchdog() from clocksource_enqueue_watchdog() and use it on clocksource register/rating change/unregister. After all, lobotomized monkeys may need some love too. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Dexuan Cui <decui@microsoft.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Link: http://lkml.kernel.org/r/1453483913-25672-1-git-send-email-vkuznets@redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* clocksource: Add CPU info to clocksource watchdog reportingSeiichi Ikarashi2015-12-071-2/+2
| | | | | | | | | | | The clocksource watchdog reporting was improved by 0b046b217ad4c6. I want to add the info of CPU where the watchdog detects a deviation because it is necessary to identify the trouble spot if the clocksource is TSC. Signed-off-by: Seiichi Ikarashi <s.ikarashi@jp.fujitsu.com> [jstultz: Tweaked commit message] Signed-off-by: John Stultz <john.stultz@linaro.org>
* remove abs64()Andrew Morton2015-11-101-1/+1
| | | | | | | | | | | | | | | Switch everything to the new and more capable implementation of abs(). Mainly to give the new abs() a bit of a workout. Cc: Michal Nazarewicz <mina86@mina86.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'v4.3-rc5' into timers/core, to pick up fixes before applying new ↵Ingo Molnar2015-10-121-1/+1
|\ | | | | | | | | | | changes Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * clocksource: Fix abs() usage w/ 64bit valuesJohn Stultz2015-10-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes one cases where abs() was being used with 64-bit nanosecond values, where the result may be capped at 32-bits. This potentially could cause watchdog false negatives on 32-bit systems, so this patch addresses the issue by using abs64(). Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1442279124-7309-2-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | clocksource: Remove return statement from void functionsGuillaume Gomez2015-10-111-3/+2Star
| | | | | | | | | | | | | | Signed-off-by: Guillaume Gomez <guillaume1.gomez@gmail.com> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/CAAOQCfSDgmqSWDBsetau%2ByF8x0%2BDagCF_pfFw0p5xH_BKkKEog@mail.gmail.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | time: Fix spelling in commentsZhen Lei2015-09-221-1/+1
|/ | | | | | | | | | | | | | | | | | Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> Cc: Hanjun Guo <guohanjun@huawei.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tianhong Ding <dingtianhong@huawei.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Xinwei Hu <huxinwei@huawei.com> Cc: Xunlei Pang <pang.xunlei@linaro.org> Cc: Zefan Li <lizefan@huawei.com> Link: http://lkml.kernel.org/r/1440484973-13892-1-git-send-email-thunder.leizhen@huawei.com [ Fixed yet another typo in one of the sentences fixed. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
* clocksource: Use current logging styleJoe Perches2015-06-101-12/+12
| | | | | | | | | | | | | | | | | | | clocksource messages aren't prefixed in dmesg so it's a bit unclear what subsystem emits the messages. Use pr_fmt and pr_<level> to auto-prefix the messages appropriately. Miscellanea: o Remove "Warning" from KERN_WARNING level messages o Align "timekeeping watchdog: " messages o Coalesce formats o Align multiline arguments Signed-off-by: Joe Perches <joe@perches.com> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/1432579795.2846.75.camel@perches.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* clocksource: Improve comment explaining clocks_calc_max_nsecs()'s 50% safety ↵John Stultz2015-04-031-2/+5
| | | | | | | | | | | | | | | | | margin Ingo noted that the description of clocks_calc_max_nsecs()'s 50% safety margin was somewhat circular. So this patch tries to improve the comment to better explain what we mean by the 50% safety margin and why we need it. Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1427945681-29972-20-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* tick: Move core only declarations and functions to coreThomas Gleixner2015-04-011-1/+1
| | | | | | | | | | | | | | No point to expose everything to the world. People just believe such functions can be abused for whatever purposes. Sigh. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> [ Rebased on top of 4.0-rc5 ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Nicolas Pitre <nico@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/28017337.VbCUc39Gme@vostro.rjw.lan [ Merged to latest timers/core ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
* tick: Move clocksource related stuff to timekeeping.hThomas Gleixner2015-04-011-1/+1
| | | | | | | | | | | | Move clocksource related stuff to timekeeping.h and remove the pointless include from ntp.c Signed-off-by: Thomas Gleixner <tglx@linutronix.de> [ rjw: Subject ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/2714218.nM5AEfAHj0@vostro.rjw.lan Signed-off-by: Ingo Molnar <mingo@kernel.org>
* clocksource: Rename __clocksource_updatefreq_*() to ↵John Stultz2015-03-131-5/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | __clocksource_update_freq_*() Ingo requested this function be renamed to improve readability, so I've renamed __clocksource_updatefreq_scale() as well as the __clocksource_updatefreq_hz/khz() functions to avoid squishedtogethernames. This touches some of the sh clocksources, which I've not tested. The arch/arm/plat-omap change is just a comment change for consistency. Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1426133800-29329-13-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* clocksource: Add some debug info about clocksources being registeredJohn Stultz2015-03-131-0/+3
| | | | | | | | | | | | | | | | Print the mask, max_cycles, and max_idle_ns values for clocksources being registered. Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1426133800-29329-12-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* clocksource: Mostly kill clocksource_register()John Stultz2015-03-131-47/+34Star
| | | | | | | | | | | | | | | | | | | | | | | | | | A long running project has been to clean up remaining uses of clocksource_register(), replacing it with the simpler clocksource_register_khz/hz() functions. However, there are a few cases where we need to self-define our mult/shift values, so switch the function to a more obviously internal __clocksource_register() name, and consolidate much of the internal logic so we don't have duplication. Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: David S. Miller <davem@davemloft.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1426133800-29329-10-git-send-email-john.stultz@linaro.org [ Minor cleanups. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
* clocksource: Improve clocksource watchdog reportingJohn Stultz2015-03-131-9/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | The clocksource watchdog reporting has been less helpful then desired, as it just printed the delta between the two clocksources. This prevents any useful analysis of why the skew occurred. Thus this patch tries to improve the output when we mark a clocksource as unstable, printing out the cycle last and now values for both the current clocksource and the watchdog clocksource. This will allow us to see if the result was due to a false positive caused by a problematic watchdog. Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1426133800-29329-9-git-send-email-john.stultz@linaro.org [ Minor cleanups of kernel messages. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
* clocksource: Add 'max_cycles' to 'struct clocksource'John Stultz2015-03-121-12/+16
| | | | | | | | | | | | | | | | | | In order to facilitate clocksource validation, add a 'max_cycles' field to the clocksource structure which will hold the maximum cycle value that can safely be multiplied without potentially causing an overflow. Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1426133800-29329-4-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* clocksource: Simplify the logic around clocksource wrapping safety marginsJohn Stultz2015-03-121-14/+12Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The clocksource logic has a number of places where we try to include a safety margin. Most of these are 12% safety margins, but they are inconsistently applied and sometimes are applied on top of each other. Additionally, in the previous patch, we corrected an issue where we unintentionally in effect created a 50% safety margin, which these 12.5% margins where then added to. So to simplify the logic here, this patch removes the various 12.5% margins, and consolidates adding the margin in one place: clocks_calc_max_nsecs(). Additionally, Linus prefers a 50% safety margin, as it allows bad clock values to be more easily caught. This should really have no net effect, due to the corrected issue earlier which caused greater then 50% margins to be used w/o issue. Signed-off-by: John Stultz <john.stultz@linaro.org> Acked-by: Stephen Boyd <sboyd@codeaurora.org> (for the sched_clock.c bit) Cc: Dave Jones <davej@codemonkey.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1426133800-29329-3-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* clocksource: Simplify the clocks_calc_max_nsecs() logicJohn Stultz2015-03-121-12/+3Star
| | | | | | | | | | | | | | | | | | | | | | | | The previous clocks_calc_max_nsecs() code had some unecessarily complex bit logic to find the max interval that could cause multiplication overflows. Since this is not in the hot path, just do the divide to make it easier to read. The previous implementation also had a subtle issue that it avoided overflows with signed 64-bit values, where as the intervals are always unsigned. This resulted in overly conservative intervals, which other safety margins were then added to, reducing the intended interval length. Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1426133800-29329-2-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* time: move the timecounter/cyclecounter code into its own file.Richard Cochran2014-12-311-76/+0Star
| | | | | | | | | | The timecounter code has almost nothing to do with the clocksource code. Let it live in its own file. This will help isolate the timecounter users from the clocksource users in the source tree. Signed-off-by: Richard Cochran <richardcochran@gmail.com> Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* clocksource: Fix 'clcoksource' typo in commentJames Hartley2014-10-291-1/+1
| | | | | | | Simple typo in a comment, so fix it. Signed-off-by: James Hartley <james.hartley@imgtec.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* clocksource: Make delta calculation a functionThomas Gleixner2014-07-241-5/+7
| | | | | | | | | | | | We want to move the TSC sanity check into core code to make NMI safe accessors to clock monotonic[_raw] possible. For this we need to sanity check the delta calculation. Create a helper function and convert all sites to use it. [ Build fix from jstultz ] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
* time: Fix signedness bug in sysfs_get_uname() and its callersPatrick Palka2013-10-191-1/+1
| | | | | | | | | | | | | | | sysfs_get_uname() is erroneously declared as returning size_t even though it may return a negative value, specifically -EINVAL. Its callers then check whether its return value is less than zero and indeed that is never the case for size_t. This patch changes sysfs_get_uname() to return ssize_t and makes sure its callers use ssize_t accordingly. Signed-off-by: Patrick Palka <patrick@parcs.ath.cx> [jstultz: Didn't apply cleanly, as a similar partial fix was also applied so had to resolve the collisions] Signed-off-by: John Stultz <john.stultz@linaro.org>
* clocksource: Fix 'ret' data type of sysfs_override_clocksource() and ↵Elad Wexler2013-09-171-2/+2
| | | | | | | | | | | | | | | sysfs_unbind_clocksource() sysfs_override_clocksource(): The expression 'if (ret >= 0)' is always true. This will cause clocksource_select() to always run. Thus modified ret to be of type ssize_t. sysfs_unbind_clocksource(): The expression 'if (ret < 0)' is always false. So in case sysfs_get_uname() failed, the expression won't take an effect. Thus modified ret to be of type ssize_t. Signed-off-by: Elad Wexler <elad.wexler@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
* Merge branch 'fortglx/3.12/time' into fortglx/3.13/timeJohn Stultz2013-09-171-0/+1
|\ | | | | | | | | | | Merge in the timekeeping changes that missed 3.12 Signed-off-by: John Stultz <john.stultz@linaro.org>
| * clocksource: Fix !CONFIG_CLOCKSOURCE_WATCHDOG compilePrarit Bhargava2013-07-231-0/+1
| | | | | | | | | | | | | | | | | | | | | | If I explicitly disable the clocksource watchdog in the x86 Kconfig, the x86 kernel will not compile unless this is properly defined. Cc: John Stultz <john.stultz@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86@kernel.org Signed-off-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
* | clocksource: Extract max nsec calculation into separate functionStephen Boyd2013-07-301-15/+30
|/ | | | | | | | | | We need to calculate the same number in the clocksource code and the sched_clock code, so extract this code into its own function. We also drop the min_t and just use min() because the two types are the same. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: John Stultz <john.stultz@linaro.org>