- 23 6月, 2014 1 次提交
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由 Thomas Gleixner 提交于
Except for Kconfig.HZ. That needs a separate treatment. Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 19 6月, 2013 1 次提交
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由 Viresh Kumar 提交于
Most of the stuff from kernel/sched.c was moved to kernel/sched/core.c long time back and the comments/Documentation never got updated. I figured it out when I was going through sched-domains.txt and so thought of fixing it globally. I haven't crossed check if the stuff that is referenced in sched/core.c by all these files is still present and hasn't changed as that wasn't the motive behind this patch. Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org> Signed-off-by: NPeter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/cdff76a265326ab8d71922a1db5be599f20aad45.1370329560.git.viresh.kumar@linaro.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>
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- 16 3月, 2013 2 次提交
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由 John Stultz 提交于
When warping the clock (from a local time RTC), use timekeeping_inject_offset() to atomically add the offset. This avoids any minor time error caused by the delay between reading the time, and then setting the adjusted time. Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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由 Dong Zhu 提交于
If the Hardware Clock kept in local time,kernel will adjust the time to be UTC time.But if Hardware Clock kept in UTC time,system will make a dummy settimeofday call first (sys_tz.tz_minuteswest = 0) to make sure the time is not shifted,so at this point I think maybe it is not necessary to set the kernel time once the sys_tz.tz_minuteswest is zero. Signed-off-by: NDong Zhu <bluezhudong@gmail.com> [jstultz: Updated to merge with conflicting changes ] Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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- 22 2月, 2013 1 次提交
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由 Greg Kroah-Hartman 提交于
How is the compiler even handling exported functions that are marked inline? Anyway, these shouldn't be inline because of that, so remove that marking. Based on a larger patch by Mark Charlebois to get LLVM to build the kernel. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Mark Charlebois <mcharleb@qualcomm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: hank <pyu@redhat.com> Cc: John Stultz <john.stultz@linaro.org> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 09 2月, 2013 1 次提交
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由 Prarit Bhargava 提交于
At init time, if the system time is "warped" forward in warp_clock() it will differ from the hardware clock by sys_tz.tz_minuteswest. This time difference is not taken into account when ntp updates the hardware clock, and this causes the system time to jump forward by this offset every reboot. The kernel must take this offset into account when writing the system time to the hardware clock in the ntp code. This patch adds persistent_clock_is_local which indicates that an offset has been applied in warp_clock() and accounts for the "warp" before writing the hardware clock. x86 does not have this problem as rtc writes are software limited to a +/-15 minute window relative to the current rtc time. Other arches, such as powerpc, however do a full synchronization of the system time to the rtc and will see this problem. [v2]: generated against tip/timers/core Signed-off-by: NPrarit Bhargava <prarit@redhat.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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- 25 9月, 2012 1 次提交
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由 John Stultz 提交于
Since users will need to include timekeeper_internal.h, move update_vsyscall definitions to timekeeper_internal.h. Cc: Tony Luck <tony.luck@intel.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Turner <pjt@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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- 16 3月, 2012 1 次提交
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由 Thomas Gleixner 提交于
There is no global irq lock which makes a syscall magically SMP safe. Remove the outdated comment concerning do_settimeofday() as well. Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
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- 31 10月, 2011 1 次提交
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由 Paul Gortmaker 提交于
The changed files were only including linux/module.h for the EXPORT_SYMBOL infrastructure, and nothing else. Revector them onto the isolated export header for faster compile times. Nothing to see here but a whole lot of instances of: -#include <linux/module.h> +#include <linux/export.h> This commit is only changing the kernel dir; next targets will probably be mm, fs, the arch dirs, etc. Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
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- 21 9月, 2011 1 次提交
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由 hank 提交于
The parameter's origin type is long. On an i386 architecture, it can easily be larger than 0x80000000, causing this function to convert it to a sign-extended u64 type. Change the type to unsigned long so we get the correct result. Signed-off-by: Nhank <pyu@redhat.com> Cc: John Stultz <john.stultz@linaro.org> Cc: <stable@kernel.org> [ build fix ] Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 02 2月, 2011 1 次提交
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由 Richard Cochran 提交于
Both settimeofday() and clock_settime() promise with a 'const' attribute not to alter the arguments passed in. This patch adds the missing 'const' attribute into the various kernel functions implementing these calls. Signed-off-by: NRichard Cochran <richard.cochran@omicron.at> Acked-by: NJohn Stultz <johnstul@us.ibm.com> LKML-Reference: <20110201134417.545698637@linutronix.de> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 31 1月, 2011 1 次提交
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由 Torben Hohn 提交于
Move the jiffies access functions to the jiffies clocksource code. [ tglx: Add missing include ] Signed-off-by: NTorben Hohn <torbenh@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: johnstul@us.ibm.com Cc: yong.zhang0@gmail.com Cc: hch@infradead.org LKML-Reference: <20110127145900.23248.73352.stgit@localhost> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 26 1月, 2011 1 次提交
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由 Venkatesh Pallipadi 提交于
Add nsecs_to_cputime64 interface. This is used in following patches that updates cpu irq stat based on ns granularity info in IRQ_TIME_ACCOUNTING. Tested-by: NShaun Ruffell <sruffell@digium.com> Signed-off-by: NVenkatesh Pallipadi <venki@google.com> Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1292980144-28796-3-git-send-email-venki@google.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 29 11月, 2010 1 次提交
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由 Jesper Juhl 提交于
These warnings are spewed during a build of a 'allnoconfig' kernel (especially the ones from u64_stats_sync.h show up a lot) when building with -Wextra (which I often do).. They are a) annoying b) easy to get rid of. This patch kills them off. include/linux/u64_stats_sync.h:70:1: warning: ‘inline’ is not at beginning of declaration include/linux/u64_stats_sync.h:77:1: warning: ‘inline’ is not at beginning of declaration include/linux/u64_stats_sync.h:84:1: warning: ‘inline’ is not at beginning of declaration include/linux/u64_stats_sync.h:96:1: warning: ‘inline’ is not at beginning of declaration include/linux/u64_stats_sync.h:115:1: warning: ‘inline’ is not at beginning of declaration include/linux/u64_stats_sync.h:127:1: warning: ‘inline’ is not at beginning of declaration kernel/time.c:241:1: warning: ‘inline’ is not at beginning of declaration kernel/time.c:257:1: warning: ‘inline’ is not at beginning of declaration kernel/perf_event.c:4513:1: warning: ‘inline’ is not at beginning of declaration mm/page_alloc.c:4012:1: warning: ‘inline’ is not at beginning of declaration Signed-off-by: NJesper Juhl <jj@chaosbits.net> Signed-off-by: NJiri Kosina <jkosina@suse.cz>
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- 27 7月, 2010 1 次提交
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由 John Stultz 提交于
Now that all arches have been converted over to use generic time via clocksources or arch_gettimeoffset(), we can remove the GENERIC_TIME config option and simplify the generic code. Signed-off-by: NJohn Stultz <johnstul@us.ibm.com> LKML-Reference: <1279068988-21864-4-git-send-email-johnstul@us.ibm.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 24 5月, 2010 1 次提交
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由 Thomas Gleixner 提交于
commit 64ce4c2f (time: Clean up warp_clock()) breaks the timezone update in a very subtle way. To avoid the direct access to timekeeping internals it adds the timezone delta to the current time with timespec_add_safe(). This works nicely when the timezone delta is > 0. If timezone delta is < 0 then the wrap check in timespec_add_safe() triggers and timespec_add_safe() returns TIME_MAX and screws up timekeeping completely. The comment above timespec_add_safe() says: It's assumed that both values are valid (>= 0) Add the timezone seconds adjustment directly. Reported-by: NRafael J. Wysocki <rjw@sisk.pl> Tested-by: NRafael J. Wysocki <rjw@sisk.pl> Acked-by: NJohn Stultz <johnstul@us.ibm.com> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 30 3月, 2010 1 次提交
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由 Tejun Heo 提交于
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: NTejun Heo <tj@kernel.org> Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
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- 13 3月, 2010 1 次提交
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由 John Stultz 提交于
warp_clock() currently accesses timekeeping internal state directly, which is unnecessary. Convert it to use the proper timekeeping interfaces. Signed-off-by: NJohn Stultz <johnstul@us.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 23 12月, 2009 1 次提交
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由 Linus Torvalds 提交于
This reverts commit 7bc7d637, as requested by John Stultz. Quoting John: "Petr Titěra reported an issue where he saw odd atime regressions with 2.6.33 where there were a full second worth of nanoseconds in the nanoseconds field. He also reviewed the time code and narrowed down the problem: unhandled overflow of the nanosecond field caused by rounding up the sub-nanosecond accumulated time. Details: * At the end of update_wall_time(), we currently round up the sub-nanosecond portion of accumulated time when storing it into xtime. This was added to avoid time inconsistencies caused when the sub-nanosecond portion was truncated when storing into xtime. Unfortunately we don't handle the possible second overflow caused by that rounding. * Previously the xtime_cache code hid this overflow by normalizing the xtime value when storing into the xtime_cache. * We could try to handle the second overflow after the rounding up, but since this affects the timekeeping's internal state, this would further complicate the next accumulation cycle, causing small errors in ntp steering. As much as I'd like to get rid of it, the xtime_cache code is known to work. * The correct fix is really to include the sub-nanosecond portion in the timekeeping accessor function, so we don't need to round up at during accumulation. This would greatly simplify the accumulation code. Unfortunately, we can't do this safely until the last three non-GENERIC_TIME arches (sparc32, arm, cris) are converted (those patches are in -mm) and we kill off the spots where arches set xtime directly. This is all 2.6.34 material, so I think reverting the xtime_cache change is the best approach for now. Many thanks to Petr for both reporting and finding the issue!" Reported-by: NPetr Titěra <P.Titera@century.cz> Requested-by: Njohn stultz <johnstul@us.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 26 11月, 2009 1 次提交
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由 Hidetoshi Seto 提交于
Use of msecs_to_jiffies() for nsecs_to_cputime() have some problems: - The type of msecs_to_jiffies()'s argument is unsigned int, so it cannot convert msecs greater than UINT_MAX = about 49.7 days. - msecs_to_jiffies() returns MAX_JIFFY_OFFSET if MSB of argument is set, assuming that input was negative value. So it cannot convert msecs greater than INT_MAX = about 24.8 days too. This patch defines a new function nsecs_to_jiffies() that can deal greater values, and that can deal all incoming values as unsigned. Signed-off-by: NHidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Acked-by: NPeter Zijlstra <peterz@infradead.org> Cc: Stanislaw Gruszka <sgruszka@redhat.com> Cc: Spencer Candland <spencer@bluehost.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Amrico Wang <xiyou.wangcong@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <johnstul@linux.vnet.ibm.com> LKML-Reference: <4B0E16E7.5070307@jp.fujitsu.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 05 10月, 2009 1 次提交
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由 john stultz 提交于
With the prior logarithmic time accumulation patch, xtime will now always be within one "tick" of the current time, instead of possibly half a second off. This removes the need for the xtime_cache value, which always stored the time at the last interrupt, so this patch cleans that up removing the xtime_cache related code. This is a bit simpler, but still could use some wider testing. Signed-off-by: NJohn Stultz <johnstul@us.ibm.com> Acked-by: NThomas Gleixner <tglx@linutronix.de> Reviewed-by: NJohn Kacur <jkacur@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> LKML-Reference: <1254525855.7741.95.camel@localhost.localdomain> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 15 9月, 2009 1 次提交
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由 Thomas Gleixner 提交于
set_normalized_timespec() nsec argument is of type long. The recent timekeeping changes of ktime_get_ts() feed ts->tv_nsec + tomono.tv_nsec + nsecs to set_normalized_timespec(). On 32 bit machines that sum can be larger than (1 << 31) and therefor result in a negative value which screws up the result completely. Make the nsec argument of set_normalized_timespec() s64 to fix the problem at hand. This also prevents similar problems for future users of set_normalized_timespec(). Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Tested-by: NCarsten Emde <carsten.emde@osadl.org> LKML-Reference: <new-submission> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: John Stultz <johnstul@us.ibm.com>
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- 14 1月, 2009 1 次提交
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由 Heiko Carstens 提交于
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
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- 07 1月, 2009 1 次提交
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由 Paul Mackerras 提交于
At the moment, the times() system call will appear to fail for a period shortly after boot, while the value it want to return is between -4095 and -1. The same thing will also happen for the time() system call on 32-bit platforms some time in 2106 or so. On some platforms, such as x86, this is unavoidable because of the system call ABI, but other platforms such as powerpc have a separate error indication from the return value, so system calls can in fact return small negative values without indicating an error. On those platforms, force_successful_syscall_return() provides a way to indicate that the system call return value should not be treated as an error even if it is in the range which would normally be taken as a negative error number. This adds a force_successful_syscall_return() call to the time() and times() system calls plus their 32-bit compat versions, so that they don't erroneously indicate an error on those platforms whose system call ABI has a separate error indication. This will not affect anything on other platforms. Joakim Tjernlund added the fix for time() and the compat versions of time() and times(), after I did the fix for times(). Signed-off-by: NJoakim Tjernlund <Joakim.Tjernlund@transmode.se> Signed-off-by: NPaul Mackerras <paulus@samba.org> Acked-by: NDavid S. Miller <davem@davemloft.net> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 06 9月, 2008 1 次提交
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由 Thomas Gleixner 提交于
For the select() rework, it's important to be able to add timespec structures in an overflow-safe manner. This patch adds a timespec_add_safe() function for this which is similar in operation to ktime_add_safe(), but works on a struct timespec. Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
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- 03 5月, 2008 1 次提交
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由 H. Peter Anvin 提交于
Force constants in kernel/timeconst.h (except shift counts) to be 64 bits, using U64_C() constructor macros, and eliminate constants that cannot be represented at all in 64 bits. This avoids warnings with some gcc versions. Drop generating 64-bit constants, since we have no real hope of getting a full set (operation on 64-bit values requires a 128-bit intermediate result, which gcc only supports on 64-bit platforms, and only with libgcc support on some.) Note that the use of these constants does not depend on if we are on a 32- or 64-bit architecture. This resolves Bugzilla 10153. Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
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- 01 5月, 2008 2 次提交
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由 Roman Zippel 提交于
x86 is the only arch right now, which provides an optimized for div_long_long_rem and it has the downside that one has to be very careful that the divide doesn't overflow. The API is a little akward, as the arguments for the unsigned divide are signed. The signed version also doesn't handle a negative divisor and produces worse code on 64bit archs. There is little incentive to keep this API alive, so this converts the few users to the new API. Signed-off-by: NRoman Zippel <zippel@linux-m68k.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Christoph Lameter <clameter@sgi.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Roman Zippel 提交于
This converts a few users of do_div to div_[su]64 and this demonstrates nicely how it can reduce some expressions to one-liners. Signed-off-by: NRoman Zippel <zippel@linux-m68k.org> Cc: john stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 29 4月, 2008 1 次提交
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由 Robert P. J. Day 提交于
Following an experimental deletion of the unnecessary directive #include <linux/slab.h> from the header file <linux/percpu.h>, these files under kernel/ were exposed as needing to include one of <linux/slab.h> or <linux/gfp.h>, so explicit includes were added where necessary. Signed-off-by: NRobert P. J. Day <rpjday@crashcourse.ca> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 22 4月, 2008 1 次提交
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由 YOSHIFUJI Hideaki 提交于
Sorry I have just realized set_normalized_timespec() (used in timespec_sub()) is not exported, and link will fail because of it... Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 09 2月, 2008 2 次提交
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由 H. Peter Anvin 提交于
When the conversion factor between jiffies and milli- or microseconds is not a single multiply or divide, as for the case of HZ == 300, we currently do a multiply followed by a divide. The intervening result, however, is subject to overflows, especially since the fraction is not simplified (for HZ == 300, we multiply by 300 and divide by 1000). This is exposed to the user when passing a large timeout to poll(), for example. This patch replaces the multiply-divide with a reciprocal multiplication on 32-bit platforms. When the input is an unsigned long, there is no portable way to do this on 64-bit platforms there is no portable way to do this since it requires a 128-bit intermediate result (which gcc does support on 64-bit platforms but may generate libgcc calls, e.g. on 64-bit s390), but since the output is a 32-bit integer in the cases affected, just simplify the multiply-divide (*3/10 instead of *300/1000). The reciprocal multiply used can have off-by-one errors in the upper half of the valid output range. This could be avoided at the expense of having to deal with a potential 65-bit intermediate result. Since the intent is to avoid overflow problems and most of the other time conversions are only semiexact, the off-by-one errors were considered an acceptable tradeoff. At Ralf Baechle's suggestion, this version uses a Perl script to compute the necessary constants. We already have dependencies on Perl for kernel compiles. This does, however, require the Perl module Math::BigInt, which is included in the standard Perl distribution starting with version 5.8.0. In order to support older versions of Perl, include a table of canned constants in the script itself, and structure the script so that Math::BigInt isn't required if pulling values from said table. Running the script requires that the HZ value is available from the Makefile. Thus, this patch also adds the Kconfig variable CONFIG_HZ to the architectures which didn't already have it (alpha, cris, frv, h8300, m32r, m68k, m68knommu, sparc, v850, and xtensa.) It does *not* touch the sh or sh64 architectures, since Paul Mundt has dealt with those separately in the sh tree. Signed-off-by: NH. Peter Anvin <hpa@zytor.com> Cc: Ralf Baechle <ralf@linux-mips.org>, Cc: Sam Ravnborg <sam@ravnborg.org>, Cc: Paul Mundt <lethal@linux-sh.org>, Cc: Richard Henderson <rth@twiddle.net>, Cc: Michael Starvik <starvik@axis.com>, Cc: David Howells <dhowells@redhat.com>, Cc: Yoshinori Sato <ysato@users.sourceforge.jp>, Cc: Hirokazu Takata <takata@linux-m32r.org>, Cc: Geert Uytterhoeven <geert@linux-m68k.org>, Cc: Roman Zippel <zippel@linux-m68k.org>, Cc: William L. Irwin <sparclinux@vger.kernel.org>, Cc: Chris Zankel <chris@zankel.net>, Cc: H. Peter Anvin <hpa@zytor.com>, Cc: Jan Engelhardt <jengelh@computergmbh.de> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Li Zefan 提交于
Fix typo in comments. BTW: I have to fix coding style in arch/ia64/kernel/time.c also, otherwise checkpatch.pl will be complaining. Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: john stultz <johnstul@us.ibm.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 07 2月, 2008 2 次提交
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由 Andrew Morton 提交于
Avoid calling do_div(x, 1) in this case. Cc: David Fries <david@fries.net> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 David Fries 提交于
The kernel has a divide by zero crash when trying to run the system timer less than 100Hz. The problem is x/(HZ/USER_HZ) and related. Now x*(USER_HZ/HZ) will be used if HZ<USER_HZ. I'm running the Linux kernel under qemu and went to run a slower system timer to take less CPU (and battery) on the host. I found that the kernel paniced under emulation because of a divide by zero in three places. Here is the patch. The base git was updated today 01-05-2008. I went for a 20Hz system time by adding config HZ_20 etc to kernel/Kconfig.hz. With this patch I verified the system timer by looking at /proc/interrupts. [akpm@linux-foundation.org: partially clean up the macro maze] Signed-off-by: NDavid Fries <david@fries.net> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 02 2月, 2008 1 次提交
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由 Thomas Gleixner 提交于
xtime_cache needs to be updated whenever xtime and or wall_to_monotic are changed. Otherwise users of xtime_cache might see a stale (and in the case of timezone changes utterly wrong) value until the next update happens. Fixup the obvious places, which miss this update. Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Acked-by: NJohn Stultz <johnstul@us.ibm.com> Tested-by: NDhaval Giani <dhaval@linux.vnet.ibm.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 19 10月, 2007 2 次提交
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由 Daniel Walker 提交于
Signed-off-by: NDaniel Walker <dwalker@mvista.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Tony Breeds 提交于
On platforms that copy sys_tz into the vdso (currently only x86_64, soon to include powerpc), it is possible for the vdso to get out of sync if a user calls (admittedly unusual) settimeofday(NULL, ptr). This patch adds a hook for architectures that set CONFIG_GENERIC_TIME_VSYSCALL to ensure when sys_tz is updated they can also updatee their copy in the vdso. Signed-off-by: NTony Breeds <tony@bakeyournoodle.com> Cc: Andi Kleen <ak@suse.de> Cc: Tony Luck <tony.luck@intel.com> Acked-by: NJohn Stultz <johnstul@us.ibm.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 17 10月, 2007 2 次提交
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由 Jesper Juhl 提交于
This patch cleans up duplicate includes in kernel/ Signed-off-by: NJesper Juhl <jesper.juhl@gmail.com> Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: NSatyam Sharma <ssatyam@cse.iitk.ac.in> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Ingo Molnar 提交于
improve performance of sys_time(). sys_time() returns time in seconds, but it does so by calling do_gettimeofday() and then returning the tv_sec portion of the GTOD time. But the data structure "xtime", which is updated by every timer/scheduler tick, already offers HZ granularity time. the patch improves the sysbench oltp macrobenchmark by 4-5% on an AMD dual-core system: v2.6.23: #threads 1: transactions: 4073 (407.23 per sec.) 2: transactions: 8530 (852.81 per sec.) 3: transactions: 8321 (831.88 per sec.) 4: transactions: 8407 (840.58 per sec.) 5: transactions: 8070 (806.74 per sec.) v2.6.23 + sys_time-speedup.patch: 1: transactions: 4281 (428.09 per sec.) 2: transactions: 8910 (890.85 per sec.) 3: transactions: 8659 (865.79 per sec.) 4: transactions: 8676 (867.34 per sec.) 5: transactions: 8532 (852.91 per sec.) and by 4-5% on an Intel dual-core system too: 2.6.23: 1: transactions: 4560 (455.94 per sec.) 2: transactions: 10094 (1009.30 per sec.) 3: transactions: 9755 (975.36 per sec.) 4: transactions: 9859 (985.78 per sec.) 5: transactions: 9701 (969.72 per sec.) 2.6.23 + sys_time-speedup.patch: 1: transactions: 4779 (477.84 per sec.) 2: transactions: 10103 (1010.14 per sec.) 3: transactions: 10141 (1013.93 per sec.) 4: transactions: 10371 (1036.89 per sec.) 5: transactions: 10178 (1017.50 per sec.) (the more CPUs the system has, the more speedup this patch gives for this particular workload.) Signed-off-by: NIngo Molnar <mingo@elte.hu> Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 26 7月, 2007 1 次提交
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由 john stultz 提交于
This avoids use of the kernel-internal "xtime" variable directly outside of the actual time-related functions. Instead, use the helper functions that we already have available to us. This doesn't actually change any behaviour, but this will allow us to fix the fact that "xtime" isn't updated very often with CONFIG_NO_HZ (because much of the realtime information is maintained as separate offsets to 'xtime'), which has caused interfaces that use xtime directly to get a time that is out of sync with the real-time clock by up to a third of a second or so. Signed-off-by: NJohn Stultz <johnstul@us.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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