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* x86_64: prepare shared lib/delay.cThomas Gleixner2007-10-111-57/+0
| | | | | Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* [PATCH] x86-64: Make x86_64 udelay() round up instead of down.Paolo 'Blaisorblade' Giarrusso2006-12-071-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | Port two patches from i386 to x86_64 delay.c to make sure all rounding is done upward instead of downward. There is no sign in commit messages that the mismatch was done on purpose, and "delay() guarantees sleeping at least for the specified time" is still a valid rule IMHO. The original x86 patches are both from pre-GIT era, i.e.: "[PATCH] round up in __udelay()" in commit 54c7e1f5cc6771ff644d7bc21a2b829308bd126f "[PATCH] add 1 in __const_udelay()" in commit 42c77a9801b8877d8b90f65f75db758822a0bccc (both commits are from converted BK repository to x86_64). AK: fixed gcc warning linux/arch/x86_64/lib/delay.c:43: warning: suggest parentheses around + or - inside shift (did this actually work?) Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andi Kleen <ak@suse.de>
* Remove all inclusions of <linux/config.h>Dave Jones2006-10-041-1/+0
| | | | | | kbuild explicitly includes this at build time. Signed-off-by: Dave Jones <davej@redhat.com>
* [PATCH] x86_64: Move export symbols to their C functionsAndi Kleen2006-06-261-0/+5
| | | | | | | | Only exports for assembler files are left in x8664_ksyms.c Originally inspired by a patch from Al Viro Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] x86_64: Make udelay more accurateRoss Biro2006-01-111-1/+1
| | | | | | | | | | | | | | | The attempt to avoid overflow in __delay caused varying precision on different CPUs depending on differences in the CPU speed. We should be able to do this multiplication with out overflowing provided the cpu is running at less than about 128 GHz. xloops < 20000 * 0x10c6. loops_per_jiffy * HZ <= cpu_clock_speed. So if the cpu clock speed < 2^64/(20000 * 0x10c6) = 2^64/ 51E6CC0 < 2^64/2^27 = 2^37 = 128G we will not overflow the calculation. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] x86_64: Remove unused variable in delay.cAndi Kleen2005-07-281-2/+0
| | | | | | Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Platform SMIs and their interferance with tsc based delay calibrationVenkatesh Pallipadi2005-06-231-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Issue: Current tsc based delay_calibration can result in significant errors in loops_per_jiffy count when the platform events like SMIs (System Management Interrupts that are non-maskable) are present. This could lead to potential kernel panic(). This issue is becoming more visible with 2.6 kernel (as default HZ is 1000) and on platforms with higher SMI handling latencies. During the boot time, SMIs are mostly used by BIOS (for things like legacy keyboard emulation). Description: The psuedocode for current delay calibration with tsc based delay looks like (0) Estimate a value for loops_per_jiffy (1) While (loops_per_jiffy estimate is accurate enough) (2) wait for jiffy transition (jiffy1) (3) Note down current tsc (tsc1) (4) loop until tsc becomes tsc1 + loops_per_jiffy (5) check whether jiffy changed since jiffy1 or not and refine loops_per_jiffy estimate Consider the following cases Case 1: If SMIs happen between (2) and (3) above, we can end up with a loops_per_jiffy value that is too low. This results in shorted delays and kernel can panic () during boot (Mostly at IOAPIC timer initialization timer_irq_works() as we don't have enough timer interrupts in a specified interval). Case 2: If SMIs happen between (3) and (4) above, then we can end up with a loops_per_jiffy value that is too high. And with current i386 code, too high lpj value (greater than 17M) can result in a overflow in delay.c:__const_udelay() again resulting in shorter delay and panic(). Solution: The patch below makes the calibration routine aware of asynchronous events like SMIs. We increase the delay calibration time and also identify any significant errors (greater than 12.5%) in the calibration and notify it to user. Patch below changes both i386 and x86-64 architectures to use this new and improved calibrate_delay_direct() routine. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] smp_processor_id() cleanupIngo Molnar2005-06-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch implements a number of smp_processor_id() cleanup ideas that Arjan van de Ven and I came up with. The previous __smp_processor_id/_smp_processor_id/smp_processor_id API spaghetti was hard to follow both on the implementational and on the usage side. Some of the complexity arose from picking wrong names, some of the complexity comes from the fact that not all architectures defined __smp_processor_id. In the new code, there are two externally visible symbols: - smp_processor_id(): debug variant. - raw_smp_processor_id(): nondebug variant. Replaces all existing uses of _smp_processor_id() and __smp_processor_id(). Defined by every SMP architecture in include/asm-*/smp.h. There is one new internal symbol, dependent on DEBUG_PREEMPT: - debug_smp_processor_id(): internal debug variant, mapped to smp_processor_id(). Also, i moved debug_smp_processor_id() from lib/kernel_lock.c into a new lib/smp_processor_id.c file. All related comments got updated and/or clarified. I have build/boot tested the following 8 .config combinations on x86: {SMP,UP} x {PREEMPT,!PREEMPT} x {DEBUG_PREEMPT,!DEBUG_PREEMPT} I have also build/boot tested x64 on UP/PREEMPT/DEBUG_PREEMPT. (Other architectures are untested, but should work just fine.) Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-161-0/+48
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!