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path: root/include/linux/delay.h
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2008-06-24x86: use cpu_khz for loops_per_jiffy calculation, cleanupAlok Kataria1-1/+1
As suggested by Ingo, remove all references to tsc from init/calibrate.c TSC is x86 specific, and using tsc in variable names in a generic file should be avoided. lpj_tsc is now called lpj_fine, since it is related to fine tuning of lpj value. Also tsc_rate_* is called timer_rate_* Signed-off-by: Alok N Kataria <akataria@vmware.com> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Daniel Hecht <dhecht@vmware.com> Cc: Tim Mann <mann@vmware.com> Cc: Zach Amsden <zach@vmware.com> Cc: Sahil Rihan <srihan@vmware.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-24x86: use cpu_khz for loops_per_jiffy calculationAlok Kataria1-0/+1
On the x86 platform we can use the value of tsc_khz computed during tsc calibration to calculate the loops_per_jiffy value. Its very important to keep the error in lpj values to minimum as any error in that may result in kernel panic in check_timer. In virtualization environment, On a highly overloaded host the guest delay calibration may sometimes result in errors beyond the ~50% that timer_irq_works can handle, resulting in the guest panicking. Does some formating changes to lpj_setup code to now have a single printk to print the bogomips value. We do this only for the boot processor because the AP's can have different base frequencies or the BIOS might boot a AP at a different frequency. Signed-off-by: Alok N Kataria <akataria@vmware.com> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Daniel Hecht <dhecht@vmware.com> Cc: Tim Mann <mann@vmware.com> Cc: Zach Amsden <zach@vmware.com> Cc: Sahil Rihan <srihan@vmware.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-03-05ndelay(): switch to C function to avoid 64-bit divisionAndrew Morton1-1/+7
We should be able to do ndelay(some_u64), but that can cause a call to __divdi3() to be emitted because the ndelay() macros does a divide. Fix it by switching to static inline which will force the u64 arg to be treated as an unsigned long. udelay() takes an unsigned long arg. [bunk@kernel.org: reported m68k build breakage] Cc: Adrian Bunk <bunk@kernel.org> Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Cc: Martin Michlmayr <tbm@cyrius.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: Adrian Bunk <bunk@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-06-21[POWERPC] Fix mdelay badness on shared processor partitionsAnton Blanchard1-4/+1
On partitioned PPC64 systems where a partition is given 1/10 of a processor, we have seen mdelay() delaying for 10 times longer than it should. The reason is that the generic mdelay(n) does n delays of 1 millisecond each. However, with 1/10 of a processor, we only get a one-millisecond timeslice every 10ms. Thus each 1 millisecond delay loop ends up taking 10ms elapsed time. The solution is just to use the PPC64 udelay function, which uses the timebase to ensure that the delay is based on elapsed time rather than how much processing time the partition has been given. (Yes, the generic mdelay uses the PPC64 udelay, but the problem is that the start time gets reset every millisecond, and each time it gets reset we lose another 9ms.) Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org> Acked-by: Andrew Morton <akpm@osdl.org>
2005-04-17Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds1-0/+50
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!