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* x86: scale cyc_2_nsec according to CPU frequencyGuillaume Chazarain2008-01-301-6/+37
| | | | | | | | | | scale the sched_clock() cyc_2_nsec scaling factor according to CPU frequency changes. [ mingo@elte.hu: simplified it and fixed it for SMP. ] Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: fix more TSC clock source calibration errorsDave Johnson2007-10-231-14/+20
| | | | | | | | | | | | | | | | | The previous patch wasn't correctly handling the 'count' variable. If a CPU gave bad results on the 1st or 2nd run but good results on the 3rd, it wouldn't do the correct thing. No idea if any such CPU exists, but the patch below handles that case by discarding the bad runs. If a bad result (too quick, or too slow) occurs on any of the 3 runs it will be discarded. Also updated some comments to explain what's going on. Signed-off-by: Dave Johnson <djohnson@sw.starentnetworks.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: fix TSC clock source calibration errorDave Johnson2007-10-231-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I ran into this problem on a system that was unable to obtain NTP sync because the clock was running very slow (over 10000ppm slow). ntpd had declared all of its peers 'reject' with 'peer_dist' reason. On investigation, the tsc_khz variable was significantly incorrect causing xtime to run slow. After a reboot tsc_khz was correct so I did a reboot test to see how often the problem occurred: Test was done on a 2000 Mhz Xeon system. Of 689 reboots, 8 of them had unacceptable tsc_khz values (>500ppm): range of tsc_khz # of boots % of boots ---------------- ---------- ---------- < 1999750 0 0.000% 1999750 - 1999800 21 3.048% 1999800 - 1999850 166 24.128% 1999850 - 1999900 241 35.029% 1999900 - 1999950 211 30.669% 1999950 - 2000000 42 6.105% 2000000 - 2000000 0 0.000% 2000050 - 2000100 0 0.000% [...] 2000100 - 2015000 1 0.145% << BAD 2015000 - 2030000 6 0.872% << BAD 2030000 - 2045000 1 0.145% << BAD 2045000 < 0 0.000% The worst boot was 2032.577 Mhz, over 1.5% off! It appears that on rare occasions, mach_countup() is taking longer to complete than necessary. I suspect that this is caused by the CPU taking a periodic SMI interrupt right at the end of the 30ms calibration loop. This would cause the loop to delay while the SMI BIOS hander runs. The resulting TSC value is beyond what it actually should be resulting in a higher tsc_khz. The below patch makes native_calculate_cpu_khz() take the best (shortest duration, lowest khz) run of it's 3 calibration loops. If a SMI goes off causing a bad result (long duration, higher khz) it will be discarded. With the patch applied, 300 boots of the same system produce good results: range of tsc_khz # of boots % of boots ---------------- ---------- ---------- < 1999750 0 0.000% 1999750 - 1999800 30 10.000% 1999800 - 1999850 166 55.333% 1999850 - 1999900 89 29.667% 1999900 - 1999950 15 5.000% 1999950 < 0 0.000% Problem was found and tested against 2.6.18. Patch is against 2.6.22. Signed-off-by: Dave Johnson <djohnson@sw.starentnetworks.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivialLinus Torvalds2007-10-191-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial: (74 commits) fix do_sys_open() prototype sysfs: trivial: fix sysfs_create_file kerneldoc spelling mistake Documentation: Fix typo in SubmitChecklist. Typo: depricated -> deprecated Add missing profile=kvm option to Documentation/kernel-parameters.txt fix typo about TBI in e1000 comment proc.txt: Add /proc/stat field small documentation fixes Fix compiler warning in smount example program from sharedsubtree.txt docs/sysfs: add missing word to sysfs attribute explanation documentation/ext3: grammar fixes Documentation/java.txt: typo and grammar fixes Documentation/filesystems/vfs.txt: typo fix include/asm-*/system.h: remove unused set_rmb(), set_wmb() macros trivial copy_data_pages() tidy up Fix typo in arch/x86/kernel/tsc_32.c file link fix for Pegasus USB net driver help remove unused return within void return function Typo fixes retrun -> return x86 hpet.h: remove broken links ...
| * Fix typo in arch/x86/kernel/tsc_32.cJosh Triplett2007-10-201-1/+1
| | | | | | | | | | Signed-off-by: Josh Triplett <josh@kernel.org> Signed-off-by: Adrian Bunk <bunk@kernel.org>
| * spelling fixes: arch/i386/Simon Arlott2007-10-201-1/+1
| | | | | | | | | | | | | | Spelling fixes in arch/i386/. Signed-off-by: Simon Arlott <simon@fire.lp0.eu> Signed-off-by: Adrian Bunk <bunk@kernel.org>
* | x86: convert cpuinfo_x86 array to a per_cpu arrayMike Travis2007-10-191-4/+4
|/ | | | | | | | | | | | | | | | | | | | | | | | | | cpu_data is currently an array defined using NR_CPUS. This means that we overallocate since we will rarely really use maximum configured cpus. When NR_CPU count is raised to 4096 the size of cpu_data becomes 3,145,728 bytes. These changes were adopted from the sparc64 (and ia64) code. An additional field was added to cpuinfo_x86 to be a non-ambiguous cpu index. This corresponds to the index into a cpumask_t as well as the per_cpu index. It's used in various places like show_cpuinfo(). cpu_data is defined to be the boot_cpu_data structure for the NON-SMP case. Signed-off-by: Mike Travis <travis@sgi.com> Acked-by: Christoph Lameter <clameter@sgi.com> Cc: Andi Kleen <ak@suse.de> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: Dmitry Torokhov <dtor@mail.ru> Cc: "Antonino A. Daplas" <adaplas@pol.net> Cc: Mark M. Hoffman <mhoffman@lightlink.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86: do not crash on non-Geode PCs in TSC probeIngo Molnar2007-10-171-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | with this fix Geode kernels can be booted (and QA-ed) on generic PCs. otherwise it crashes and burns during early bootup: Detected 2160.212 MHz processor. general protection fault: 0000 [#1] PREEMPT SMP Modules linked in: CPU: 0 EIP: 0060:[<c09071f6>] Not tainted VLI EFLAGS: 00010002 (2.6.23-rc9 #90) EIP is at tsc_init+0xa6/0x150 eax: 00000001 ebx: c1dce000 ecx: 00001900 edx: 00000001 esi: 00051000 edi: 00051000 ebp: c08fdfc4 esp: c08fdfa4 ds: 007b es: 007b fs: 00d8 gs: 0000 ss: 0068 Process swapper (pid: 0, ti=c08fc000 task=c082a180 task.ti=c08fc000) Stack: c076b870 00000870 000000d4 0000001d c0831e80 c1dce000 00051000 00051000 c08fdfcc c09053f8 c08fdff8 c09045ff 000001e2 c09040a0 00051000 00000020 0004e500 c0932140 00020800 00099800 c08ed000 01409007 00000000 Call Trace: [<c010517a>] show_trace_log_lvl+0x1a/0x30 [<c0105246>] show_stack_log_lvl+0xb6/0x100 [<c0105732>] show_registers+0x212/0x3a0 [<c0105aa4>] die+0x104/0x220 [<c0105f5f>] do_general_protection+0x1ef/0x2b0 [<c06699f2>] error_code+0x72/0x78 [<c09053f8>] time_init+0x8/0x20 [<c09045ff>] start_kernel+0x1af/0x320 [<00000000>] 0x0 ======================= Code: 31 d2 b8 00 00 09 3d f7 35 2c 70 9b c0 a3 04 95 8f c0 e8 ce 4e 99 ff b8 e0 45 93 c0 e8 94 b1 c5 ff e8 7f 3d 80 ff b9 00 19 00 00 <0f> 32 f6 c4 01 74 07 83 25 24 ce 82 c0 fd 8b 0d 20 ce 82 c0 b8 EIP: [<c09071f6>] tsc_init+0xa6/0x150 SS:ESP 0068:c08fdfa4 Kernel panic - not syncing: Attempted to kill the idle task! Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* Delete filenames in comments.Dave Jones2007-10-131-6/+0
| | | | | | | | | | | | | | | Since the x86 merge, lots of files that referenced their own filenames are no longer correct. Rather than keep them up to date, just delete them, as they add no real value. Additionally: - fix up comment formatting in scx200_32.c - Remove a credit from myself in setup_64.c from a time when we had no SCM - remove longwinded history from tsc_32.c which can be figured out from git. Signed-off-by: Dave Jones <davej@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'dmi-const' of ↵Linus Torvalds2007-10-111-1/+1
| | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/misc-2.6 * 'dmi-const' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/misc-2.6: drivers/firmware: const-ify DMI API and internals
* i386: move kernelThomas Gleixner2007-10-111-0/+413
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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