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2020-08-26s390: convert to GENERIC_VDSOSven Schnelle1-56/+10
Convert s390 to generic vDSO. There are a few special things on s390: - vDSO can be called without a stack frame - glibc did this in the past. So we need to allocate a stackframe on our own. - The former assembly code used stcke to get the TOD clock and applied time steering to it. We need to do the same in the new code. This is done in the architecture specific __arch_get_hw_counter function. The steering information is stored in an architecure specific area in the vDSO data. - CPUCLOCK_VIRT is now handled with a syscall fallback, which might be slower/less accurate than the old implementation. The getcpu() function stays as an assembly function because there is no generic implementation and the code is just a few lines. Performance number from my system do 100 mio gettimeofday() calls: Plain syscall: 8.6s Generic VDSO: 1.3s old ASM VDSO: 1s So it's a bit slower but still much faster than syscalls. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-07-22s390/time: improve comparison for tod steeringHeiko Carstens1-1/+1
It doesn't make sense to add zero shifted by 15. It's still zero. Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-07-22s390/time: use CLOCKSOURCE_MASKHeiko Carstens1-1/+1
Make use of CLOCKSOURCE_MASK instead of open-coding it. Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-07-01s390/stp: allow group and users to read stp sysfs filesSven Schnelle1-27/+22
There are no secrets in these files, so allow all users to read it. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2020-06-29s390: convert to msecs_to_jiffies()Sven Schnelle1-1/+1
Instead of using the old 'jiffies + HZ {/,*} something' calculation use msecs_to_jiffies() as that makes the code more readable. Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2020-06-16s390/vdso: fix vDSO clock_getres()Vincenzo Frascino1-0/+1
clock_getres in the vDSO library has to preserve the same behaviour of posix_get_hrtimer_res(). In particular, posix_get_hrtimer_res() does: sec = 0; ns = hrtimer_resolution; and hrtimer_resolution depends on the enablement of the high resolution timers that can happen either at compile or at run time. Fix the s390 vdso implementation of clock_getres keeping a copy of hrtimer_resolution in vdso data and using that directly. Link: https://lkml.kernel.org/r/20200324121027.21665-1-vincenzo.frascino@arm.com Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> [heiko.carstens@de.ibm.com: use llgf for proper zero extension] Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-10-31s390/time: remove monotonic_clock()Heiko Carstens1-9/+0
Remove unused monotonic_clock() function. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2018-07-20s390/time: Remove read_boot_clock64()Pavel Tatashin1-13/+0
read_boot_clock64() was replaced by read_persistent_wall_and_boot_offset() so remove it. Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: steven.sistare@oracle.com Cc: daniel.m.jordan@oracle.com Cc: linux@armlinux.org.uk Cc: schwidefsky@de.ibm.com Cc: heiko.carstens@de.ibm.com Cc: john.stultz@linaro.org Cc: sboyd@codeaurora.org Cc: hpa@zytor.com Cc: douly.fnst@cn.fujitsu.com Cc: peterz@infradead.org Cc: prarit@redhat.com Cc: feng.tang@intel.com Cc: pmladek@suse.com Cc: gnomes@lxorguk.ukuu.org.uk Cc: linux-s390@vger.kernel.org Cc: boris.ostrovsky@oracle.com Cc: jgross@suse.com Cc: pbonzini@redhat.com Link: https://lkml.kernel.org/r/20180719205545.16512-18-pasha.tatashin@oracle.com
2018-07-20s390/time: Add read_persistent_wall_and_boot_offset()Pavel Tatashin1-0/+18
read_persistent_wall_and_boot_offset() will replace read_boot_clock64() because on some architectures it is more convenient to read both sources as one may depend on the other. For s390, implementation is the same as read_boot_clock64() but also calling and returning value of read_persistent_clock64() Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: steven.sistare@oracle.com Cc: daniel.m.jordan@oracle.com Cc: linux@armlinux.org.uk Cc: heiko.carstens@de.ibm.com Cc: john.stultz@linaro.org Cc: sboyd@codeaurora.org Cc: hpa@zytor.com Cc: douly.fnst@cn.fujitsu.com Cc: peterz@infradead.org Cc: prarit@redhat.com Cc: feng.tang@intel.com Cc: pmladek@suse.com Cc: gnomes@lxorguk.ukuu.org.uk Cc: linux-s390@vger.kernel.org Cc: boris.ostrovsky@oracle.com Cc: jgross@suse.com Cc: pbonzini@redhat.com Link: https://lkml.kernel.org/r/20180719205545.16512-15-pasha.tatashin@oracle.com
2017-11-30Merge branch 'for-linus' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 fixes from Martin Schwidefsky: - SPDX identifiers are added to more of the s390 specific files. - The ELF_ET_DYN_BASE base patch from Kees is reverted, with the change some old 31-bit programs crash. - Bug fixes and cleanups. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (29 commits) s390/gs: add compat regset for the guarded storage broadcast control block s390: revert ELF_ET_DYN_BASE base changes s390: Remove redundant license text s390: crypto: Remove redundant license text s390: include: Remove redundant license text s390: kernel: Remove redundant license text s390: add SPDX identifiers to the remaining files s390: appldata: add SPDX identifiers to the remaining files s390: pci: add SPDX identifiers to the remaining files s390: mm: add SPDX identifiers to the remaining files s390: crypto: add SPDX identifiers to the remaining files s390: kernel: add SPDX identifiers to the remaining files s390: sthyi: add SPDX identifiers to the remaining files s390: drivers: Remove redundant license text s390: crypto: Remove redundant license text s390: virtio: add SPDX identifiers to the remaining files s390: scsi: zfcp_aux: add SPDX identifier s390: net: add SPDX identifiers to the remaining files s390: char: add SPDX identifiers to the remaining files s390: cio: add SPDX identifiers to the remaining files ...
2017-11-24s390: kernel: add SPDX identifiers to the remaining filesGreg Kroah-Hartman1-0/+1
It's good to have SPDX identifiers in all files to make it easier to audit the kernel tree for correct licenses. Update the arch/s390/kernel/ 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 Thomas Gleixner, Philippe Ombredanne, and Kate Stewart. Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-11-21treewide: setup_timer() -> timer_setup()Kees Cook1-2/+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>
2017-08-23s390/dasd: Change unsigned long long to unsigned longJan Höppner1-1/+1
Unsigned long long and unsigned long were different in size for 31-bit. For 64-bit the size for both datatypes is 8 Bytes and since the support for 31-bit is long gone we can clean up a little and change everything to unsigned long. Change get_phys_clock() along the way to accept unsigned long as well so that the DASD code can be consistent. Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Jan Höppner <hoeppner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-07-26s390/time: add support for the TOD clock epoch extensionMartin Schwidefsky1-20/+45
The TOD epoch extension adds 8 epoch bits to the TOD clock to provide a continuous clock after 2042/09/17. The store-clock-extended (STCKE) instruction will store the epoch index in the first byte of the 16 bytes stored by the instruction. The read_boot_clock64 and the read_presistent_clock64 functions need to take the additional bits into account to give the correct result after 2042/09/17. The clock-comparator register will stay 64 bit wide. The comparison of the clock-comparator with the TOD clock is limited to bytes 1 to 8 of the extended TOD format. To deal with the overflow problem due to an epoch change the clock-comparator sign control in CR0 can be used to switch the comparison of the 64-bit TOD clock with the clock-comparator to a signed comparison. The decision between the signed vs. unsigned clock-comparator comparisons is done at boot time. Only if the TOD clock is in the second half of a 142 year epoch the signed comparison is used. This solves the epoch overflow issue as long as the machine is booted at least once in an epoch. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-05-26s390/kernel: Use stop_machine_cpuslocked()Sebastian Andrzej Siewior1-3/+3
stp_work_fn() holds get_online_cpus() while invoking stop_machine(). stop_machine() invokes get_online_cpus() as well. This is correct, but prevents the conversion of the hotplug locking to a percpu rwsem. Use stop_machine_cpuslocked() to avoid the nested call. Convert *_online_cpus() to the new interfaces while at it. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: linux-s390@vger.kernel.org Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: David Hildenbrand <dahi@linux.vnet.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Link: http://lkml.kernel.org/r/20170524081548.250203087@linutronix.de
2017-04-14s390/time: Set ->min_delta_ticks and ->max_delta_ticksNicolai Stange1-0/+2
In preparation for making the clockevents core NTP correction aware, all clockevent device drivers must set ->min_delta_ticks and ->max_delta_ticks rather than ->min_delta_ns and ->max_delta_ns: a clockevent device's rate is going to change dynamically and thus, the ratio of ns to ticks ceases to stay invariant. Currently, the s390's CPU timer clockevent device is initialized as follows: cd->min_delta_ns = 1; cd->max_delta_ns = LONG_MAX; Note that the device's time to cycle conversion factor, i.e. cd->mult / (2^cd->shift), is approx. equal to 4. Hence, this would translate to cd->min_delta_ticks = 4; cd->max_delta_ticks = 4 * LONG_MAX; However, a minimum value of 1ns is in the range of noise anyway and the clockevent core will take care of this by increasing it to 1us or so. Furthermore, 4*LONG_MAX would overflow the unsigned long argument the clockevent devices gets programmed with. Thus, initialize ->min_delta_ticks with 1 and ->max_delta_ticks with ULONG_MAX. This patch alone doesn't introduce any change in functionality as the clockevents core still looks exclusively at the (untouched) ->min_delta_ns and ->max_delta_ns. As soon as this has changed, a followup patch will purge the initialization of ->min_delta_ns and ->max_delta_ns from this driver. Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: David Hildenbrand <dahi@linux.vnet.ibm.com> Cc: linux-s390@vger.kernel.org Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar1-0/+1
<linux/sched/clock.h> We are going to split <linux/sched/clock.h> out of <linux/sched.h>, which will have to be picked up from other headers and .c files. Create a trivial placeholder <linux/sched/clock.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: 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>
2017-02-17s390: kernel: Audit and remove any unnecessary uses of module.hPaul Gortmaker1-1/+1
Historically a lot of these existed because we did not have a distinction between what was modular code and what was providing support to modules via EXPORT_SYMBOL and friends. That changed when we forked out support for the latter into the export.h file. This means we should be able to reduce the usage of module.h in code that is obj-y Makefile or bool Kconfig. The advantage in doing so is that module.h itself sources about 15 other headers; adding significantly to what we feed cpp, and it can obscure what headers we are effectively using. Since module.h was the source for init.h (for __init) and for export.h (for EXPORT_SYMBOL) we consider each change instance for the presence of either and replace as needed. Build testing revealed some implicit header usage that was fixed up accordingly. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-02-07s390/debug: make debug event time stamps relative to the boot TOD clockMartin Schwidefsky1-2/+1
The debug features currently uses absolute TOD time stamps for the debug events. Given that the TOD clock can jump forward and backward due to STP sync checks the order of debug events can get obfuscated. Replace the absolute TOD time stamps with a delta to the IPL time stamp. On a STP sync check the TOD clock correction is added to the IPL time stamp as well to make the deltas unaffected by STP sync check. The readout of the debug feature entries will convert the deltas back to absolute time stamps based on the Unix epoch. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-01-16s390: use false/true when using boolHeiko Carstens1-1/+1
Yet another trivial patch to reduce the noise that coccinelle generates. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-12-25clocksource: Use a plain u64 instead of cycle_tThomas Gleixner1-1/+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>
2016-12-24Replace <asm/uaccess.h> with <linux/uaccess.h> globallyLinus Torvalds1-1/+1
This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-17s390/time: fix clocksource steering for negative clock offsetsMartin Schwidefsky1-4/+3
The TOD clock offset injected by an STP sync check can be negative. If the resulting total tod_steering_delta gets negative the kernel will panic. Change the type of tod_steering_delta to a signed type. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Fixes: 75c7b6f3f6ba ("s390/time: steer clocksource on STP sync events") Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-10-28s390/time: steer clocksource on STP sync eventsMartin Schwidefsky1-1/+40
On STP sync events the TOD clock will jump in time, either forward or backward. The TOD clocksource claims to be continuous but in case of an STP sync with a negative offset it is not. Subtract the offset injected by the STP sync check from the result of the TOD clocksource to make it continuous again. Add code to drift the offset towards zero with a fixed rate, steering 1 second in ~9 hours. Suggested-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-10-28s390/time: adjust last_update_clock at clock synchronizationMartin Schwidefsky1-0/+2
The last_update_clock time stamp in the lowcore should be adjusted by the TOD clock delta that is created by the clock synchronization. Otherwise the calculation of the steal time will be incorrect. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-10-28s390/time: refactor clock syncMartin Schwidefsky1-80/+69
Merge clock_sync_cpu into stp_sync_clock and split out the update of the global and per-CPU clock fields into clock_sync_global and clock_sync_local. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-08-29s390/time: avoid races when updating tb_update_countDavid Hildenbrand1-5/+0
The increment might not be atomic and we're not holding the timekeeper_lock. Therefore we might lose an update to count, resulting in VDSO being trapped in a loop. As other archs also simply update the values and count doesn't seem to have an impact on reloading of these values in VDSO code, let's just remove the update of tb_update_count. Suggested-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-08-29s390/time: fixup the clock comparator on all cpusDavid Hildenbrand1-0/+1
By leaving fixup_cc unset, only the clock comparator of the cpu actually doing the sync is fixed up until now. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-08-29s390/time: cleanup etr leftoversDavid Hildenbrand1-21/+9
There are still some etr leftovers and wrong comments, let's clean that up. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-08-29s390/time: simplify stp time syncsDavid Hildenbrand1-46/+4
The way we call do_adjtimex() today is broken. It has 0 effect, as ADJ_OFFSET_SINGLESHOT (0x0001) in the kernel maps to !ADJ_ADJTIME (in contrast to user space where it maps to ADJ_OFFSET_SINGLESHOT | ADJ_ADJTIME - 0x8001). !ADJ_ADJTIME will silently ignore all adjustments without STA_PLL being active. We could switch to ADJ_ADJTIME or turn STA_PLL on, but still we would run into some problems: - Even when switching to nanoseconds, we lose accuracy. - Successive calls to do_adjtimex() will simply overwrite any leftovers from the previous call (if not fully handled) - Anything that NTP does using the sysctl heavily interferes with our use. - !ADJ_ADJTIME will silently round stuff > or < than 0.5 seconds Reusing do_adjtimex() here just feels wrong. The whole STP synchronization works right now *somehow* only, as do_adjtimex() does nothing and our TOD clock jumps in time, although it shouldn't. This is especially bad as the clock could jump backwards in time. We will have to find another way to fix this up. As leap seconds are also not properly handled yet, let's just get rid of all this complex logic altogether and use the correct clock_delta for fixing up the clock comparator and keeping the sched_clock monotonic. This change should have 0 effect on the current STP mechanism. Once we know how to best handle sync events and leap second updates, we'll start with a fresh implementation. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-13s390/time: remove ETR supportMartin Schwidefsky1-988/+1
The External-Time-Reference (ETR) clock synchronization interface has been superseded by Server-Time-Protocol (STP). Remove the outdated ETR interface. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-13s390/time: add leap seconds to initial system timeMartin Schwidefsky1-2/+15
The PTFF instruction can be used to retrieve information about UTC including the current number of leap seconds. Use this value to convert the coordinated server time value of the TOD clock to a proper UTC timestamp to initialize the system time. Without this correction the system time will be off by the number of leap seonds until it has been corrected via NTP. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-13s390/time: LPAR offset handlingMartin Schwidefsky1-8/+38
It is possible to specify a user offset for the TOD clock, e.g. +2 hours. The TOD clock will carry this offset even if the clock is synchronized with STP. This makes the time stamps acquired with get_sync_clock() useless as another LPAR migth use a different TOD offset. Use the PTFF instrution to get the TOD epoch difference and subtract it from the TOD clock value to get a physical timestamp. As the epoch difference contains the sync check delta as well the LPAR offset value to the physical clock needs to be refreshed after each clock synchronization. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-13s390/time: STP sync clock correctionMartin Schwidefsky1-6/+5
The sync clock operation of the channel subsystem call for STP delivers the TOD clock difference as a result. Use this TOD clock difference instead of the difference between the TOD timestamps before and after the sync clock operation. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-17param: convert some "on"/"off" users to strtoboolKees Cook1-6/+2
This changes several users of manual "on"/"off" parsing to use strtobool. Some side-effects: - these uses will now parse y/n/1/0 meaningfully too - the early_param uses will now bubble up parse errors Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Cc: Amitkumar Karwar <akarwar@marvell.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Joe Perches <joe@perches.com> Cc: Kalle Valo <kvalo@codeaurora.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Nishant Sarmukadam <nishants@marvell.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Steve French <sfrench@samba.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-07s390: Use pr_warn instead of pr_warningJoe Perches1-4/+2
Convert the uses of pr_warning to pr_warn so there are fewer uses of the old pr_warning. Miscellanea: o Align arguments o Coalesce formats Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14s390/etr,stp: fix possible deadlock on machine checkHeiko Carstens1-10/+21
The first level machine check handler for etr and stp machine checks may call queue_work() while in nmi context. This may deadlock e.g. if the machine check happened when the interrupted context did hold a lock, that also will be acquired by queue_work(). Therefore split etr and stp machine check handling into first and second level handling. The second level handling will then issue the queue_work() call in process context which avoids the potential deadlock. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-09-03Merge branch 'locking-core-for-linus' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking and atomic updates from Ingo Molnar: "Main changes in this cycle are: - Extend atomic primitives with coherent logic op primitives (atomic_{or,and,xor}()) and deprecate the old partial APIs (atomic_{set,clear}_mask()) The old ops were incoherent with incompatible signatures across architectures and with incomplete support. Now every architecture supports the primitives consistently (by Peter Zijlstra) - Generic support for 'relaxed atomics': - _acquire/release/relaxed() flavours of xchg(), cmpxchg() and {add,sub}_return() - atomic_read_acquire() - atomic_set_release() This came out of porting qwrlock code to arm64 (by Will Deacon) - Clean up the fragile static_key APIs that were causing repeat bugs, by introducing a new one: DEFINE_STATIC_KEY_TRUE(name); DEFINE_STATIC_KEY_FALSE(name); which define a key of different types with an initial true/false value. Then allow: static_branch_likely() static_branch_unlikely() to take a key of either type and emit the right instruction for the case. To be able to know the 'type' of the static key we encode it in the jump entry (by Peter Zijlstra) - Static key self-tests (by Jason Baron) - qrwlock optimizations (by Waiman Long) - small futex enhancements (by Davidlohr Bueso) - ... and misc other changes" * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (63 commits) jump_label/x86: Work around asm build bug on older/backported GCCs locking, ARM, atomics: Define our SMP atomics in terms of _relaxed() operations locking, include/llist: Use linux/atomic.h instead of asm/cmpxchg.h locking/qrwlock: Make use of _{acquire|release|relaxed}() atomics locking/qrwlock: Implement queue_write_unlock() using smp_store_release() locking/lockref: Remove homebrew cmpxchg64_relaxed() macro definition locking, asm-generic: Add _{relaxed|acquire|release}() variants for 'atomic_long_t' locking, asm-generic: Rework atomic-long.h to avoid bulk code duplication locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations locking, compiler.h: Cast away attributes in the WRITE_ONCE() magic locking/static_keys: Make verify_keys() static jump label, locking/static_keys: Update docs locking/static_keys: Provide a selftest jump_label: Provide a self-test s390/uaccess, locking/static_keys: employ static_branch_likely() x86, tsc, locking/static_keys: Employ static_branch_likely() locking/static_keys: Add selftest locking/static_keys: Add a new static_key interface locking/static_keys: Rework update logic locking/static_keys: Add static_key_{en,dis}able() helpers ...
2015-09-01Merge branch 'timers-core-for-linus' of ↵Linus Torvalds1-6/+0
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer updates from Thomas Gleixner: "Rather large, but nothing exiting: - new range check for settimeofday() to prevent that boot time becomes negative. - fix for file time rounding - a few simplifications of the hrtimer code - fix for the proc/timerlist code so the output of clock realtime timers is accurate - more y2038 work - tree wide conversion of clockevent drivers to the new callbacks" * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (88 commits) hrtimer: Handle failure of tick_init_highres() gracefully hrtimer: Unconfuse switch_hrtimer_base() a bit hrtimer: Simplify get_target_base() by returning current base hrtimer: Drop return code of hrtimer_switch_to_hres() time: Introduce timespec64_to_jiffies()/jiffies_to_timespec64() time: Introduce current_kernel_time64() time: Introduce struct itimerspec64 time: Add the common weak version of update_persistent_clock() time: Always make sure wall_to_monotonic isn't positive time: Fix nanosecond file time rounding in timespec_trunc() timer_list: Add the base offset so remaining nsecs are accurate for non monotonic timers cris/time: Migrate to new 'set-state' interface kernel: broadcast-hrtimer: Migrate to new 'set-state' interface xtensa/time: Migrate to new 'set-state' interface unicore/time: Migrate to new 'set-state' interface um/time: Migrate to new 'set-state' interface sparc/time: Migrate to new 'set-state' interface sh/localtimer: Migrate to new 'set-state' interface score/time: Migrate to new 'set-state' interface s390/time: Migrate to new 'set-state' interface ...
2015-08-10s390/time: Migrate to new 'set-state' interfaceViresh Kumar1-6/+0
Migrate s390 driver to the new 'set-state' interface provided by clockevents core, the earlier 'set-mode' interface is marked obsolete now. This also enables us to implement callbacks for new states of clockevent devices, for example: ONESHOT_STOPPED. We weren't doing anything in the ->set_mode() callback. So, this patch doesn't provide any set-state callbacks. Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Cc: linux-s390@vger.kernel.org Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-08-04KVM: s390: host STP toleration for VMsFan Zhang1-3/+13
If the host has STP enabled, the TOD of the host will be changed during synchronization phases. These are performed during a stop_machine() call. As the guest TOD is based on the host TOD, we have to make sure that: - no VCPU is in the SIE (implicitly guaranteed via stop_machine()) - manual guest TOD calculations are not affected "Epoch" is the guest TOD clock delta to the host TOD clock. We have to adjust that value during the STP synchronization and make sure that code that accesses the epoch won't get interrupted in between (via disabling preemption). Signed-off-by: Fan Zhang <zhangfan@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-07-27atomic: Replace atomic_{set,clear}_mask() usagePeter Zijlstra1-2/+2
Replace the deprecated atomic_{set,clear}_mask() usage with the now ubiquous atomic_{or,andnot}() functions. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-05-22s390: time: Provide read_boot_clock64() and read_persistent_clock64()Xunlei Pang1-3/+3
As part of addressing the "y2038 problem" for in-kernel uses, this patch converts read_boot_clock() to read_boot_clock64() and read_persistent_clock() to read_persistent_clock64() using timespec64. Rename some instances of 'timespec' to 'timespec64' in time.c and related references Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org> [jstultz: Fixed minor style and grammer tweaks pointed out by Ingo] Signed-off-by: John Stultz <john.stultz@linaro.org>
2015-03-27time: Rename timekeeper::tkr to timekeeper::tkr_monoPeter Zijlstra1-9/+9
In preparation of adding another tkr field, rename this one to tkr_mono. Also rename tk_read_base::base_mono to tk_read_base::base, since the structure is not specific to CLOCK_MONOTONIC and the mono name got added to the tk_read_base instance. Lots of trivial churn. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: John Stultz <john.stultz@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20150319093400.344679419@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-13clocksource: Mostly kill clocksource_register()John Stultz1-1/+1
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>
2014-10-27s390/kprobes: make use of NOKPROBE_SYMBOL()Heiko Carstens1-1/+2
Use NOKPROBE_SYMBOL() instead of __kprobes annotation. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-10-15Merge branch 'for-3.18-consistent-ops' of ↵Linus Torvalds1-3/+3
git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu Pull percpu consistent-ops changes from Tejun Heo: "Way back, before the current percpu allocator was implemented, static and dynamic percpu memory areas were allocated and handled separately and had their own accessors. The distinction has been gone for many years now; however, the now duplicate two sets of accessors remained with the pointer based ones - this_cpu_*() - evolving various other operations over time. During the process, we also accumulated other inconsistent operations. This pull request contains Christoph's patches to clean up the duplicate accessor situation. __get_cpu_var() uses are replaced with with this_cpu_ptr() and __this_cpu_ptr() with raw_cpu_ptr(). Unfortunately, the former sometimes is tricky thanks to C being a bit messy with the distinction between lvalues and pointers, which led to a rather ugly solution for cpumask_var_t involving the introduction of this_cpu_cpumask_var_ptr(). This converts most of the uses but not all. Christoph will follow up with the remaining conversions in this merge window and hopefully remove the obsolete accessors" * 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (38 commits) irqchip: Properly fetch the per cpu offset percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t -fix ia64: sn_nodepda cannot be assigned to after this_cpu conversion. Use __this_cpu_write. percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t Revert "powerpc: Replace __get_cpu_var uses" percpu: Remove __this_cpu_ptr clocksource: Replace __this_cpu_ptr with raw_cpu_ptr sparc: Replace __get_cpu_var uses avr32: Replace __get_cpu_var with __this_cpu_write blackfin: Replace __get_cpu_var uses tile: Use this_cpu_ptr() for hardware counters tile: Replace __get_cpu_var uses powerpc: Replace __get_cpu_var uses alpha: Replace __get_cpu_var ia64: Replace __get_cpu_var uses s390: cio driver &__get_cpu_var replacements s390: Replace __get_cpu_var uses mips: Replace __get_cpu_var uses MIPS: Replace __get_cpu_var uses in FPU emulator. arm: Replace __this_cpu_ptr with raw_cpu_ptr ...
2014-09-09s390/vdso: add vdso support for coarse clocksMartin Schwidefsky1-0/+13
Add CLOCK_REALTIME_COARSE and CLOCK_MONOTONIC_COARSE optimization to the 64-bit and 31-bit vdso. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-08-26s390: Replace __get_cpu_var usesChristoph Lameter1-3/+3
__get_cpu_var() is used for multiple purposes in the kernel source. One of them is address calculation via the form &__get_cpu_var(x). This calculates the address for the instance of the percpu variable of the current processor based on an offset. Other use cases are for storing and retrieving data from the current processors percpu area. __get_cpu_var() can be used as an lvalue when writing data or on the right side of an assignment. __get_cpu_var() is defined as : #define __get_cpu_var(var) (*this_cpu_ptr(&(var))) __get_cpu_var() always only does an address determination. However, store and retrieve operations could use a segment prefix (or global register on other platforms) to avoid the address calculation. this_cpu_write() and this_cpu_read() can directly take an offset into a percpu area and use optimized assembly code to read and write per cpu variables. This patch converts __get_cpu_var into either an explicit address calculation using this_cpu_ptr() or into a use of this_cpu operations that use the offset. Thereby address calculations are avoided and less registers are used when code is generated. At the end of the patch set all uses of __get_cpu_var have been removed so the macro is removed too. The patch set includes passes over all arches as well. Once these operations are used throughout then specialized macros can be defined in non -x86 arches as well in order to optimize per cpu access by f.e. using a global register that may be set to the per cpu base. Transformations done to __get_cpu_var() 1. Determine the address of the percpu instance of the current processor. DEFINE_PER_CPU(int, y); int *x = &__get_cpu_var(y); Converts to int *x = this_cpu_ptr(&y); 2. Same as #1 but this time an array structure is involved. DEFINE_PER_CPU(int, y[20]); int *x = __get_cpu_var(y); Converts to int *x = this_cpu_ptr(y); 3. Retrieve the content of the current processors instance of a per cpu variable. DEFINE_PER_CPU(int, y); int x = __get_cpu_var(y) Converts to int x = __this_cpu_read(y); 4. Retrieve the content of a percpu struct DEFINE_PER_CPU(struct mystruct, y); struct mystruct x = __get_cpu_var(y); Converts to memcpy(&x, this_cpu_ptr(&y), sizeof(x)); 5. Assignment to a per cpu variable DEFINE_PER_CPU(int, y) __get_cpu_var(y) = x; Converts to this_cpu_write(y, x); 6. Increment/Decrement etc of a per cpu variable DEFINE_PER_CPU(int, y); __get_cpu_var(y)++ Converts to this_cpu_inc(y) Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> CC: linux390@de.ibm.com Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2014-07-23timekeeping: Create struct tk_read_base and use it in struct timekeeperThomas Gleixner1-8/+8
The members of the new struct are the required ones for the new NMI safe accessor to clcok monotonic. In order to reuse the existing timekeeping code and to make the update of the fast NMI safe timekeepers a simple memcpy use the struct for the timekeeper as well and convert all users. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
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