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* x86: Don't enable F00F workaround on Intel Quark processorsDave Jones2014-10-291-2/+3
| | | | | | | | | | | | | The Intel Quark processor is a part of family 5, but does not have the F00F bug present in Pentiums of the same family. Pentiums were models 0 through 8, Quark is model 9. Signed-off-by: Dave Jones <davej@redhat.com> Cc: Bryan O'Donoghue <pure.logic@nexus-software.ie> Link: http://lkml.kernel.org/r/20141028175753.GA12743@redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86: Add cpu_detect_cache_sizes to init_intel() add Quark legacy_cache()Bryan O'Donoghue2014-10-081-1/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Intel processors which don't report cache information via cpuid(2) or cpuid(4) need quirk code in the legacy_cache_size callback to report this data. For Intel that callback is is intel_size_cache(). This patch enables calling of cpu_detect_cache_sizes() inside of init_intel() and hence the calling of the legacy_cache callback in intel_size_cache(). Adding this call will ensure that PIII Tualatin currently in intel_size_cache() and Quark SoC X1000 being added to intel_size_cache() in this patch will report their respective cache sizes. This model of calling cpu_detect_cache_sizes() is consistent with AMD/Via/Cirix/Transmeta and Centaur. Also added is a string to idenitfy the Quark as Quark SoC X1000 giving better and more descriptive output via /proc/cpuinfo Adding cpu_detect_cache_sizes to init_intel() will enable calling of intel_size_cache() on Intel processors which currently no code can reach. Therefore this patch will also re-enable reporting of PIII Tualatin cache size information as well as add Quark SoC X1000 support. Comment text and cache flow logic suggested by Thomas Gleixner Signed-off-by: Bryan O'Donoghue <pure.logic@nexus-software.ie> Cc: davej@redhat.com Cc: hmh@hmh.eng.br Link: http://lkml.kernel.org/r/1412641189-12415-3-git-send-email-pure.logic@nexus-software.ie Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86/intel/quark: Switch off CR4.PGE so TLB flush uses CR3 insteadBryan O'Donoghue2014-09-241-0/+15
| | | | | | | | | | | | | | | | | | Quark x1000 advertises PGE via the standard CPUID method PGE bits exist in Quark X1000's PTEs. In order to flush an individual PTE it is necessary to reload CR3 irrespective of the PTE.PGE bit. See Quark Core_DevMan_001.pdf section 6.4.11 This bug was fixed in Galileo kernels, unfixed vanilla kernels are expected to crash and burn on this platform. Signed-off-by: Bryan O'Donoghue <pure.logic@nexus-software.ie> Cc: Borislav Petkov <bp@alien8.de> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/1411514784-14885-1-git-send-email-pure.logic@nexus-software.ie Signed-off-by: Ingo Molnar <mingo@kernel.org>
* Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds2014-08-041-26/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mm changes from Ingo Molnar: "The main change in this cycle is the rework of the TLB range flushing code, to simplify, fix and consolidate the code. By Dave Hansen" * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Set TLB flush tunable to sane value (33) x86/mm: New tunable for single vs full TLB flush x86/mm: Add tracepoints for TLB flushes x86/mm: Unify remote INVLPG code x86/mm: Fix missed global TLB flush stat x86/mm: Rip out complicated, out-of-date, buggy TLB flushing x86/mm: Clean up the TLB flushing code x86/smep: Be more informative when signalling an SMEP fault
| * x86/mm: Rip out complicated, out-of-date, buggy TLB flushingDave Hansen2014-07-311-26/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I think the flush_tlb_mm_range() code that tries to tune the flush sizes based on the CPU needs to get ripped out for several reasons: 1. It is obviously buggy. It uses mm->total_vm to judge the task's footprint in the TLB. It should certainly be using some measure of RSS, *NOT* ->total_vm since only resident memory can populate the TLB. 2. Haswell, and several other CPUs are missing from the intel_tlb_flushall_shift_set() function. Thus, it has been demonstrated to bitrot quickly in practice. 3. It is plain wrong in my vm: [ 0.037444] Last level iTLB entries: 4KB 0, 2MB 0, 4MB 0 [ 0.037444] Last level dTLB entries: 4KB 0, 2MB 0, 4MB 0 [ 0.037444] tlb_flushall_shift: 6 Which leads to it to never use invlpg. 4. The assumptions about TLB refill costs are wrong: http://lkml.kernel.org/r/1337782555-8088-3-git-send-email-alex.shi@intel.com (more on this in later patches) 5. I can not reproduce the original data: https://lkml.org/lkml/2012/5/17/59 I believe the sample times were too short. Running the benchmark in a loop yields times that vary quite a bit. Note that this leaves us with a static ceiling of 1 page. This is a conservative, dumb setting, and will be revised in a later patch. This also removes the code which attempts to predict whether we are flushing data or instructions. We expect instruction flushes to be relatively rare and not worth tuning for explicitly. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Link: http://lkml.kernel.org/r/20140731154055.ABC88E89@viggo.jf.intel.com Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Mel Gorman <mgorman@suse.de> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | Merge branch 'x86-cpufeature-for-linus' of ↵Linus Torvalds2014-08-041-2/+2
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpufeature updates from Ingo Molnar: "The main changes in this cycle were: - Continued cleanups of CPU bugs mis-marked as 'missing features', by Borislav Petkov. - Detect the xsaves/xrstors feature and releated cleanup, by Fenghua Yu" * 'x86-cpufeature-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, cpu: Kill cpu_has_mp x86, amd: Cleanup init_amd x86/cpufeature: Add bug flags to /proc/cpuinfo x86, cpufeature: Convert more "features" to bugs x86/xsaves: Detect xsaves/xrstors feature x86/cpufeature.h: Reformat x86 feature macros
| * | x86, cpufeature: Convert more "features" to bugsBorislav Petkov2014-06-181-2/+2
| |/ | | | | | | | | | | | | | | | | | | | | | | X86_FEATURE_FXSAVE_LEAK, X86_FEATURE_11AP and X86_FEATURE_CLFLUSH_MONITOR are not really features but synthetic bits we use for applying different bug workarounds. Call them what they really are, and make sure they get the proper cross-CPU behavior (OR rather than AND). Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1403042783-23278-1-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* / x86, cpu: Fix cache topology for early P4-SMTPeter Zijlstra2014-07-231-11/+11
|/ | | | | | | | | | | | | | | | | | | | | | | | | P4 systems with cpuid level < 4 can have SMT, but the cache topology description available (cpuid2) does not include SMP information. Now we know that SMT shares all cache levels, and therefore we can mark all available cache levels as shared. We do this by setting cpu_llc_id to ->phys_proc_id, since that's the same for each SMT thread. We can do this unconditional since if there's no SMT its still true, the one CPU shares cache with only itself. This fixes a problem where such CPUs report an incorrect LLC CPU mask. This in turn fixes a crash in the scheduler where the topology was build wrong, it assumes the LLC mask to include at least the SMT CPUs. Cc: Josh Boyer <jwboyer@redhat.com> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com> Tested-by: Bruno Wolff III <bruno@wolff.to> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20140722133514.GM12054@laptop.lan Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* Merge branch 'x86-nuke-platforms-for-linus' of ↵Linus Torvalds2014-04-021-4/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 old platform removal from Peter Anvin: "This patchset removes support for several completely obsolete platforms, where the maintainers either have completely vanished or acked the removal. For some of them it is questionable if there even exists functional specimens of the hardware" Geert Uytterhoeven apparently thought this was a April Fool's pull request ;) * 'x86-nuke-platforms-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, platforms: Remove NUMAQ x86, platforms: Remove SGI Visual Workstation x86, apic: Remove support for IBM Summit/EXA chipset x86, apic: Remove support for ia32-based Unisys ES7000
| * x86, platforms: Remove NUMAQH. Peter Anvin2014-02-271-4/+0
| | | | | | | | | | | | | | | | | | | | The NUMAQ support seems to be unmaintained, remove it. Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: David Rientjes <rientjes@google.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/n/530CFD6C.7040705@zytor.com
* | x86, cpu: Add forcepae parameter for booting PAE kernels on PAE-disabled ↵Chris Bainbridge2014-03-201-0/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Pentium M Many Pentium M systems disable PAE but may have a functionally usable PAE implementation. This adds the "forcepae" parameter which bypasses the boot check for PAE, and sets the CPU as being PAE capable. Using this parameter will taint the kernel with TAINT_CPU_OUT_OF_SPEC. Signed-off-by: Chris Bainbridge <chris.bainbridge@gmail.com> Link: http://lkml.kernel.org/r/20140307114040.GA4997@localhost Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* | x86, intel: Make MSR_IA32_MISC_ENABLE bit constants systematicH. Peter Anvin2014-03-131-3/+7
| | | | | | | | | | | | | | | | Replace somewhat arbitrary constants for bits in MSR_IA32_MISC_ENABLE with verbose but systematic ones. Add _BIT defines for all the rest of them, too. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | x86, Intel: Convert to the new bit access MSR accessorsBorislav Petkov2014-03-131-23/+7
|/ | | | | | | | ... and save some lines of code. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1394384725-10796-4-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* Merge branch 'linus' into x86/urgentIngo Molnar2014-01-251-2/+27
|\ | | | | | | | | | | Merge in the x86 changes to apply a fix. Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds2014-01-201-0/+26
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 TLB detection update from Ingo Molnar: "A single change that extends our TLB cache size detection+reporting code" * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, cpu: Detect more TLB configuration
| | * x86, cpu: Detect more TLB configurationKirill A. Shutemov2014-01-031-0/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Intel Software Developer’s Manual covers few more TLB configurations exposed as CPUID 2 descriptors: 61H Instruction TLB: 4 KByte pages, fully associative, 48 entries 63H Data TLB: 1 GByte pages, 4-way set associative, 4 entries 76H Instruction TLB: 2M/4M pages, fully associative, 8 entries B5H Instruction TLB: 4KByte pages, 8-way set associative, 64 entries B6H Instruction TLB: 4KByte pages, 8-way set associative, 128 entries C1H Shared 2nd-Level TLB: 4 KByte/2MByte pages, 8-way associative, 1024 entries C2H DTLB DTLB: 2 MByte/$MByte pages, 4-way associative, 16 entries Let's detect them as well. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Link: http://lkml.kernel.org/r/1387801018-14499-1-git-send-email-kirill.shutemov@linux.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| * | Merge branch 'x86-cleanups-for-linus' of ↵Linus Torvalds2014-01-201-1/+0
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups from Ingo Molnar: "Misc cleanups" * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, cpu, amd: Fix a shadowed variable situation um, x86: Fix vDSO build x86: Delete non-required instances of include <linux/init.h> x86, realmode: Pointer walk cleanups, pull out invariant use of __pa() x86/traps: Clean up error exception handler definitions
| | * | x86: Delete non-required instances of include <linux/init.h>Paul Gortmaker2014-01-061-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | None of these files are actually using any __init type directives and hence don't need to include <linux/init.h>. Most are just a left over from __devinit and __cpuinit removal, or simply due to code getting copied from one driver to the next. [ hpa: undid incorrect removal from arch/x86/kernel/head_32.S ] Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Link: http://lkml.kernel.org/r/1389054026-12947-1-git-send-email-paul.gortmaker@windriver.com Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | | sched/clock, x86: Use a static_key for sched_clock_stablePeter Zijlstra2014-01-131-1/+1
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to avoid the runtime condition and variable load turn sched_clock_stable into a static_key. Also provide a shorter implementation of local_clock() and cpu_clock(int) when sched_clock_stable==1. MAINLINE PRE POST sched_clock_stable: 1 1 1 (cold) sched_clock: 329841 221876 215295 (cold) local_clock: 301773 234692 220773 (warm) sched_clock: 38375 25602 25659 (warm) local_clock: 100371 33265 27242 (warm) rdtsc: 27340 24214 24208 sched_clock_stable: 0 0 0 (cold) sched_clock: 382634 235941 237019 (cold) local_clock: 396890 297017 294819 (warm) sched_clock: 38194 25233 25609 (warm) local_clock: 143452 71234 71232 (warm) rdtsc: 27345 24245 24243 Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/n/tip-eummbdechzz37mwmpags1gjr@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | mm, x86: Revisit tlb_flushall_shift tuning for page flushes except on IvyBridgeMel Gorman2014-01-251-7/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There was a large ebizzy performance regression that was bisected to commit 611ae8e3 (x86/tlb: enable tlb flush range support for x86). The problem was related to the tlb_flushall_shift tuning for IvyBridge which was altered. The problem is that it is not clear if the tuning values for each CPU family is correct as the methodology used to tune the values is unclear. This patch uses a conservative tlb_flushall_shift value for all CPU families except IvyBridge so the decision can be revisited if any regression is found as a result of this change. IvyBridge is an exception as testing with one methodology determined that the value of 2 is acceptable. Details are in the changelog for the patch "x86: mm: Change tlb_flushall_shift for IvyBridge". One important aspect of this to watch out for is Xen. The original commit log mentioned large performance gains on Xen. It's possible Xen is more sensitive to this value if it flushes small ranges of pages more frequently than workloads on bare metal typically do. Signed-off-by: Mel Gorman <mgorman@suse.de> Tested-by: Davidlohr Bueso <davidlohr@hp.com> Reviewed-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alex Shi <alex.shi@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-dyzMww3fqugnhbhgo6Gxmtkw@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | x86: mm: change tlb_flushall_shift for IvyBridgeMel Gorman2014-01-251-1/+1
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There was a large performance regression that was bisected to commit 611ae8e3 ("x86/tlb: enable tlb flush range support for x86"). This patch simply changes the default balance point between a local and global flush for IvyBridge. In the interest of allowing the tests to be reproduced, this patch was tested using mmtests 0.15 with the following configurations configs/config-global-dhp__tlbflush-performance configs/config-global-dhp__scheduler-performance configs/config-global-dhp__network-performance Results are from two machines Ivybridge 4 threads: Intel(R) Core(TM) i3-3240 CPU @ 3.40GHz Ivybridge 8 threads: Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz Page fault microbenchmark showed nothing interesting. Ebizzy was configured to run multiple iterations and threads. Thread counts ranged from 1 to NR_CPUS*2. For each thread count, it ran 100 iterations and each iteration lasted 10 seconds. Ivybridge 4 threads 3.13.0-rc7 3.13.0-rc7 vanilla altshift-v3 Mean 1 6395.44 ( 0.00%) 6789.09 ( 6.16%) Mean 2 7012.85 ( 0.00%) 8052.16 ( 14.82%) Mean 3 6403.04 ( 0.00%) 6973.74 ( 8.91%) Mean 4 6135.32 ( 0.00%) 6582.33 ( 7.29%) Mean 5 6095.69 ( 0.00%) 6526.68 ( 7.07%) Mean 6 6114.33 ( 0.00%) 6416.64 ( 4.94%) Mean 7 6085.10 ( 0.00%) 6448.51 ( 5.97%) Mean 8 6120.62 ( 0.00%) 6462.97 ( 5.59%) Ivybridge 8 threads 3.13.0-rc7 3.13.0-rc7 vanilla altshift-v3 Mean 1 7336.65 ( 0.00%) 7787.02 ( 6.14%) Mean 2 8218.41 ( 0.00%) 9484.13 ( 15.40%) Mean 3 7973.62 ( 0.00%) 8922.01 ( 11.89%) Mean 4 7798.33 ( 0.00%) 8567.03 ( 9.86%) Mean 5 7158.72 ( 0.00%) 8214.23 ( 14.74%) Mean 6 6852.27 ( 0.00%) 7952.45 ( 16.06%) Mean 7 6774.65 ( 0.00%) 7536.35 ( 11.24%) Mean 8 6510.50 ( 0.00%) 6894.05 ( 5.89%) Mean 12 6182.90 ( 0.00%) 6661.29 ( 7.74%) Mean 16 6100.09 ( 0.00%) 6608.69 ( 8.34%) Ebizzy hits the worst case scenario for TLB range flushing every time and it shows for these Ivybridge CPUs at least that the default choice is a poor on. The patch addresses the problem. Next was a tlbflush microbenchmark written by Alex Shi at http://marc.info/?l=linux-kernel&m=133727348217113 . It measures access costs while the TLB is being flushed. The expectation is that if there are always full TLB flushes that the benchmark would suffer and it benefits from range flushing There are 320 iterations of the test per thread count. The number of entries is randomly selected with a min of 1 and max of 512. To ensure a reasonably even spread of entries, the full range is broken up into 8 sections and a random number selected within that section. iteration 1, random number between 0-64 iteration 2, random number between 64-128 etc This is still a very weak methodology. When you do not know what are typical ranges, random is a reasonable choice but it can be easily argued that the opimisation was for smaller ranges and an even spread is not representative of any workload that matters. To improve this, we'd need to know the probability distribution of TLB flush range sizes for a set of workloads that are considered "common", build a synthetic trace and feed that into this benchmark. Even that is not perfect because it would not account for the time between flushes but there are limits of what can be reasonably done and still be doing something useful. If a representative synthetic trace is provided then this benchmark could be revisited and the shift values retuned. Ivybridge 4 threads 3.13.0-rc7 3.13.0-rc7 vanilla altshift-v3 Mean 1 10.50 ( 0.00%) 10.50 ( 0.03%) Mean 2 17.59 ( 0.00%) 17.18 ( 2.34%) Mean 3 22.98 ( 0.00%) 21.74 ( 5.41%) Mean 5 47.13 ( 0.00%) 46.23 ( 1.92%) Mean 8 43.30 ( 0.00%) 42.56 ( 1.72%) Ivybridge 8 threads 3.13.0-rc7 3.13.0-rc7 vanilla altshift-v3 Mean 1 9.45 ( 0.00%) 9.36 ( 0.93%) Mean 2 9.37 ( 0.00%) 9.70 ( -3.54%) Mean 3 9.36 ( 0.00%) 9.29 ( 0.70%) Mean 5 14.49 ( 0.00%) 15.04 ( -3.75%) Mean 8 41.08 ( 0.00%) 38.73 ( 5.71%) Mean 13 32.04 ( 0.00%) 31.24 ( 2.49%) Mean 16 40.05 ( 0.00%) 39.04 ( 2.51%) For both CPUs, average access time is reduced which is good as this is the benchmark that was used to tune the shift values in the first place albeit it is now known *how* the benchmark was used. The scheduler benchmarks were somewhat inconclusive. They showed gains and losses and makes me reconsider how stable those benchmarks really are or if something else might be interfering with the test results recently. Network benchmarks were inconclusive. Almost all results were flat except for netperf-udp tests on the 4 thread machine. These results were unstable and showed large variations between reboots. It is unknown if this is a recent problems but I've noticed before that netperf-udp results tend to vary. Based on these results, changing the default for Ivybridge seems like a logical choice. Signed-off-by: Mel Gorman <mgorman@suse.de> Tested-by: Davidlohr Bueso <davidlohr@hp.com> Reviewed-by: Alex Shi <alex.shi@linaro.org> Reviewed-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-cqnadffh1tiqrshthRj3Esge@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* / x86 idle: Repair large-server 50-watt idle-power regressionLen Brown2013-12-191-1/+2
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Linux 3.10 changed the timing of how thread_info->flags is touched: x86: Use generic idle loop (7d1a941731fabf27e5fb6edbebb79fe856edb4e5) This caused Intel NHM-EX and WSM-EX servers to experience a large number of immediate MONITOR/MWAIT break wakeups, which caused cpuidle to demote from deep C-states to shallow C-states, which caused these platforms to experience a significant increase in idle power. Note that this issue was already present before the commit above, however, it wasn't seen often enough to be noticed in power measurements. Here we extend an errata workaround from the Core2 EX "Dunnington" to extend to NHM-EX and WSM-EX, to prevent these immediate returns from MWAIT, reducing idle power on these platforms. While only acpi_idle ran on Dunnington, intel_idle may also run on these two newer systems. As of today, there are no other models that are known to need this tweak. Link: http://lkml.kernel.org/r/CAJvTdK=%2BaNN66mYpCGgbHGCHhYQAKx-vB0kJSWjVpsNb_hOAtQ@mail.gmail.com Signed-off-by: Len Brown <len.brown@intel.com> Link: http://lkml.kernel.org/r/baff264285f6e585df757d58b17788feabc68918.1387403066.git.len.brown@intel.com Cc: <stable@vger.kernel.org> # 3.12.x, 3.11.x, 3.10.x Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* x86/cpu: Track legacy CPU model data only on 32-bit kernelsJan Beulich2013-10-261-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | struct cpu_dev's c_models is only ever set inside CONFIG_X86_32 conditionals (or code that's being built for 32-bit only), so there's no use of reserving the (empty) space for the model names in a 64-bit kernel. Similarly, c_size_cache is only used in the #else of a CONFIG_X86_64 conditional, so reserving space for (and in one case even initializing) that field is pointless for 64-bit kernels too. While moving both fields to the end of the structure, I also noticed that: - the c_models array size was one too small, potentially causing table_lookup_model() to return garbage on Intel CPUs (intel.c's instance was lacking the sentinel with family being zero), so the patch bumps that by one, - c_models' vendor sub-field was unused (and anyway redundant with the base structure's c_x86_vendor field), so the patch deletes it. Also rename the legacy fields so that their legacy nature stands out and comment their declarations. Signed-off-by: Jan Beulich <jbeulich@suse.com> Link: http://lkml.kernel.org/r/5265036802000078000FC4DB@nat28.tlf.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86: delete __cpuinit usage from all x86 filesPaul Gortmaker2013-07-141-15/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. Note that some harmless section mismatch warnings may result, since notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c) are flagged as __cpuinit -- so if we remove the __cpuinit from arch specific callers, we will also get section mismatch warnings. As an intermediate step, we intend to turn the linux/init.h cpuinit content into no-ops as early as possible, since that will get rid of these warnings. In any case, they are temporary and harmless. This removes all the arch/x86 uses of the __cpuinit macros from all C files. x86 only had the one __CPUINIT used in assembly files, and it wasn't paired off with a .previous or a __FINIT, so we can delete it directly w/o any corresponding additional change there. [1] https://lkml.org/lkml/2013/5/20/589 Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* Merge branch 'x86-kaslr-for-linus' of ↵Linus Torvalds2013-04-301-17/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perparatory x86 kasrl changes from Ingo Molnar: "This contains changes from the ongoing KASLR work, by Kees Cook. The main changes are the use of a read-only IDT on x86 (which decouples the userspace visible virtual IDT address from the physical address), and a rework of ELF relocation support, in preparation of random, boot-time kernel image relocation." * 'x86-kaslr-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, relocs: Refactor the relocs tool to merge 32- and 64-bit ELF x86, relocs: Build separate 32/64-bit tools x86, relocs: Add 64-bit ELF support to relocs tool x86, relocs: Consolidate processing logic x86, relocs: Generalize ELF structure names x86: Use a read-only IDT alias on all CPUs
| * x86: Use a read-only IDT alias on all CPUsKees Cook2013-04-111-17/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make a copy of the IDT (as seen via the "sidt" instruction) read-only. This primarily removes the IDT from being a target for arbitrary memory write attacks, and has the added benefit of also not leaking the kernel base offset, if it has been relocated. We already did this on vendor == Intel and family == 5 because of the F0 0F bug -- regardless of if a particular CPU had the F0 0F bug or not. Since the workaround was so cheap, there simply was no reason to be very specific. This patch extends the readonly alias to all CPUs, but does not activate the #PF to #UD conversion code needed to deliver the proper exception in the F0 0F case except on Intel family 5 processors. Signed-off-by: Kees Cook <keescook@chromium.org> Link: http://lkml.kernel.org/r/20130410192422.GA17344@www.outflux.net Cc: Eric Northup <digitaleric@google.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds2013-04-301-2/+2
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpuid changes from Ingo Molnar: "The biggest change is x86 CPU bug handling refactoring and cleanups, by Borislav Petkov" * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, CPU, AMD: Drop useless label x86, AMD: Correct {rd,wr}msr_amd_safe warnings x86: Fold-in trivial check_config function x86, cpu: Convert AMD Erratum 400 x86, cpu: Convert AMD Erratum 383 x86, cpu: Convert Cyrix coma bug detection x86, cpu: Convert FDIV bug detection x86, cpu: Convert F00F bug detection x86, cpu: Expand cpufeature facility to include cpu bugs
| * | x86, cpu: Convert F00F bug detectionBorislav Petkov2013-04-021-2/+2
| |/ | | | | | | | | | | | | | | ... to using the new facility and drop the cpuinfo_x86 member. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1363788448-31325-3-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* / x86: Add cpu capability flag X86_FEATURE_NONSTOP_TSC_S3Feng Tang2013-03-151-0/+12
|/ | | | | | | | | | | | On some new Intel Atom processors (Penwell and Cloverview), there is a feature that the TSC won't stop in S3 state, say the TSC value won't be reset to 0 after resume. This feature makes TSC a more reliable clocksource and could benefit the timekeeping code during system suspend/resume cycle, so add a flag for it. Signed-off-by: Feng Tang <feng.tang@intel.com> [jstultz: Fix checkpatch warning] Signed-off-by: John Stultz <john.stultz@linaro.org>
* Merge remote-tracking branch 'origin/x86/mm' into x86/mm2H. Peter Anvin2013-02-011-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | Explicitly merging these two branches due to nontrivial conflicts and to allow further work. Resolved Conflicts: arch/x86/kernel/head32.c arch/x86/kernel/head64.c arch/x86/mm/init_64.c arch/x86/realmode/init.c Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| * Merge tag 'v3.8-rc5' into x86/mmH. Peter Anvin2013-01-251-4/+0
| |\ | | | | | | | | | | | | | | | | | | | | | The __pa() fixup series that follows touches KVM code that is not present in the existing branch based on v3.7-rc5, so merge in the current upstream from Linus. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| * | x86: Use __pa_symbol instead of __pa on C visible symbolsAlexander Duyck2012-11-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When I made an attempt at separating __pa_symbol and __pa I found that there were a number of cases where __pa was used on an obvious symbol. I also caught one non-obvious case as _brk_start and _brk_end are based on the address of __brk_base which is a C visible symbol. In mark_rodata_ro I was able to reduce the overhead of kernel symbol to virtual memory translation by using a combination of __va(__pa_symbol()) instead of page_address(virt_to_page()). Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Link: http://lkml.kernel.org/r/20121116215640.8521.80483.stgit@ahduyck-cp1.jf.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | | Merge remote-tracking branch 'origin/x86/boot' into x86/mm2H. Peter Anvin2013-01-291-4/+0
|\ \ \ | | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | Coming patches to x86/mm2 require the changes and advanced baseline in x86/boot. Resolved Conflicts: arch/x86/kernel/setup.c mm/nobootmem.c Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| * | x86, 386 removal: Remove CONFIG_INVLPGH. Peter Anvin2012-11-291-4/+0
| |/ | | | | | | | | | | | | | | All 486+ CPUs support INVLPG, so remove the fallback 386 support code. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1354132230-21854-6-git-send-email-hpa@linux.intel.com
* / x86, mm: kill numa_64.hYinghai Lu2012-11-171-1/+0
|/ | | | | | Signed-off-by: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/1353123563-3103-44-git-send-email-yinghai@kernel.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* x86, cpu: Push TLB detection CPUID check downBorislav Petkov2012-08-061-0/+4
| | | | | | | | | | Push the max CPUID leaf check into the ->detect_tlb function and remove general test case from the generic path. Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> Link: http://lkml.kernel.org/r/1344272439-29080-3-git-send-email-bp@amd64.org Acked-by: Alex Shi <alex.shi@intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86/tlb: add tlb_flushall_shift for specific CPUAlex Shi2012-06-271-0/+34
| | | | | | | | | | | | | | | | | | | | Testing show different CPU type(micro architectures and NUMA mode) has different balance points between the TLB flush all and multiple invlpg. And there also has cases the tlb flush change has no any help. This patch give a interface to let x86 vendor developers have a chance to set different shift for different CPU type. like some machine in my hands, balance points is 16 entries on Romely-EP; while it is at 8 entries on Bloomfield NHM-EP; and is 256 on IVB mobile CPU. but on model 15 core2 Xeon using invlpg has nothing help. For untested machine, do a conservative optimization, same as NHM CPU. Signed-off-by: Alex Shi <alex.shi@intel.com> Link: http://lkml.kernel.org/r/1340845344-27557-5-git-send-email-alex.shi@intel.com Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86/tlb_info: get last level TLB entry number of CPUAlex Shi2012-06-271-0/+142
| | | | | | | | | | | | | | | | | | | | | | | | | For 4KB pages, x86 CPU has 2 or 1 level TLB, first level is data TLB and instruction TLB, second level is shared TLB for both data and instructions. For hupe page TLB, usually there is just one level and seperated by 2MB/4MB and 1GB. Although each levels TLB size is important for performance tuning, but for genernal and rude optimizing, last level TLB entry number is suitable. And in fact, last level TLB always has the biggest entry number. This patch will get the biggest TLB entry number and use it in furture TLB optimizing. Accroding Borislav's suggestion, except tlb_ll[i/d]_* array, other function and data will be released after system boot up. For all kinds of x86 vendor friendly, vendor specific code was moved to its specific files. Signed-off-by: Alex Shi <alex.shi@intel.com> Link: http://lkml.kernel.org/r/1340845344-27557-2-git-send-email-alex.shi@intel.com Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86: Simplify code by removing a !SMP #ifdefs from 'struct cpuinfo_x86'Kevin Winchester2011-12-211-2/+0
| | | | | | | | | | | | | | | | | | | | | | | Several fields in struct cpuinfo_x86 were not defined for the !SMP case, likely to save space. However, those fields still have some meaning for UP, and keeping them allows some #ifdef removal from other files. The additional size of the UP kernel from this change is not significant enough to worry about keeping up the distinction: text data bss dec hex filename 4737168 506459 972040 6215667 5ed7f3 vmlinux.o.before 4737444 506459 972040 6215943 5ed907 vmlinux.o.after for a difference of 276 bytes for an example UP config. If someone wants those 276 bytes back badly then it should be implemented in a cleaner way. Signed-off-by: Kevin Winchester <kjwinchester@gmail.com> Cc: Steffen Persvold <sp@numascale.com> Link: http://lkml.kernel.org/r/1324428742-12498-1-git-send-email-kjwinchester@gmail.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86, intel: Use c->microcode for Atom errata checkAndi Kleen2011-10-141-11/+4
| | | | | | | | | | Now that the cpu update level is available the Atom PSE errata check can use it directly without reading the MSR again. Signed-off-by: Andi Kleen <ak@linux.intel.com> Acked-by: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/r/1318466795-7393-2-git-send-email-andi@firstfloor.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86, intel: Output microcode revision in /proc/cpuinfoAndi Kleen2011-10-141-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | I got a request to make it easier to determine the microcode update level on Intel CPUs. This patch adds a new "microcode" field to /proc/cpuinfo. The microcode level is also outputed on fatal machine checks together with the other CPUID model information. I removed the respective code from the microcode update driver, it just reads the field from cpu_data. Also when the microcode is updated it fills in the new values too. I had to add a memory barrier to native_cpuid to prevent it being optimized away when the result is not used. This turns out to clean up further code which already got this information manually. This is done in followon patches. Signed-off-by: Andi Kleen <ak@linux.intel.com> Acked-by: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/r/1318466795-7393-1-git-send-email-andi@firstfloor.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86, intel, power: Correct the MSR_IA32_ENERGY_PERF_BIAS messageLen Brown2011-07-151-5/+5
| | | | | | | | | | | | | Fix the printk_once() so that it actually prints (didn't print before due to a stray comma.) [ hpa: changed to an incremental patch and adjusted the description accordingly. ] Signed-off-by: Len Brown <len.brown@intel.com> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1107151732480.18606@x980 Cc: <table@kernel.org> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* x86, intel, power: Initialize MSR_IA32_ENERGY_PERF_BIASLen Brown2011-07-141-0/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | Since 2.6.36 (23016bf0d25), Linux prints the existence of "epb" in /proc/cpuinfo, Since 2.6.38 (d5532ee7b40), the x86_energy_perf_policy(8) utility has been available in-tree to update MSR_IA32_ENERGY_PERF_BIAS. However, the typical BIOS fails to initialize the MSR, presumably because this is handled by high-volume shrink-wrap operating systems... Linux distros, on the other hand, do not yet invoke x86_energy_perf_policy(8). As a result, WSM-EP, SNB, and later hardware from Intel will run in its default hardware power-on state (performance), which assumes that users care for performance at all costs and not for energy efficiency. While that is fine for performance benchmarks, the hardware's intended default operating point is "normal" mode... Initialize the MSR to the "normal" by default during kernel boot. x86_energy_perf_policy(8) is available to change the default after boot, should the user have a different preference. Signed-off-by: Len Brown <len.brown@intel.com> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1107140051020.18606@x980 Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: <stable@kernel.org>
* Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds2011-05-191-6/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, cpu: Fix detection of Celeron Covington stepping A1 and B0 Documentation, ABI: Update L3 cache index disable text x86, AMD, cacheinfo: Fix L3 cache index disable checks x86, AMD, cacheinfo: Fix fallout caused by max3 conversion x86, cpu: Change NOP selection for certain Intel CPUs x86, cpu: Clean up and unify the NOP selection infrastructure x86, percpu: Use ASM_NOP4 instead of hardcoding P6_NOP4 x86, cpu: Move AMD Elan Kconfig under "Processor family" Fix up trivial conflicts in alternative handling (commit dc326fca2b64 "x86, cpu: Clean up and unify the NOP selection infrastructure" removed some hacky 5-byte instruction stuff, while commit d430d3d7e646 "jump label: Introduce static_branch() interface" renamed HAVE_JUMP_LABEL to CONFIG_JUMP_LABEL in the code that went away)
| * x86, cpu: Fix detection of Celeron Covington stepping A1 and B0Ondrej Zary2011-05-161-6/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | Steppings A1 and B0 of Celeron Covington are currently misdetected as Pentium II (Dixon). Fix it by removing the stepping check. [ hpa: this fixes this specific bug... the CPUID documentation specifies that the L2 cache size can disambiguate additional CPUs; this patch does not fix that. ] Signed-off-by: Ondrej Zary <linux@rainbow-software.org> Link: http://lkml.kernel.org/r/201105162138.15416.linux@rainbow-software.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | x86, mem, intel: Initialize Enhanced REP MOVSB/STOSBFenghua Yu2011-05-171-4/+15
|/ | | | | | | | | | If kernel intends to use enhanced REP MOVSB/STOSB, it must ensure IA32_MISC_ENABLE.Fast_String_Enable (bit 0) is set and CPUID.(EAX=07H, ECX=0H): EBX[bit 9] also reports 1. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1305671358-14478-3-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* x86: Unify CPU -> NUMA node mapping between 32 and 64bitTejun Heo2011-01-281-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Unlike 64bit, 32bit has been using its own cpu_to_node_map[] for CPU -> NUMA node mapping. Replace it with early_percpu variable x86_cpu_to_node_map and share the mapping code with 64bit. * USE_PERCPU_NUMA_NODE_ID is now enabled for 32bit too. * x86_cpu_to_node_map and numa_set/clear_node() are moved from numa_64 to numa. For now, on 32bit, x86_cpu_to_node_map is initialized with 0 instead of NUMA_NO_NODE. This is to avoid introducing unexpected behavior change and will be updated once init path is unified. * srat_detect_node() is now enabled for x86_32 too. It calls numa_set_node() and initializes the mapping making explicit cpu_to_node_map[] updates from map/unmap_cpu_to_node() unnecessary. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: eric.dumazet@gmail.com Cc: yinghai@kernel.org Cc: brgerst@gmail.com Cc: gorcunov@gmail.com Cc: penberg@kernel.org Cc: shaohui.zheng@intel.com Cc: rientjes@google.com LKML-Reference: <1295789862-25482-15-git-send-email-tj@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: David Rientjes <rientjes@google.com>
* x86: Unify cpu/apicid <-> NUMA node mapping between 32 and 64bitTejun Heo2011-01-281-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The mapping between cpu/apicid and node is done via apicid_to_node[] on 64bit and apicid_2_node[] + apic->x86_32_numa_cpu_node() on 32bit. This difference makes it difficult to further unify 32 and 64bit NUMA handling. This patch unifies it by replacing both apicid_to_node[] and apicid_2_node[] with __apicid_to_node[] array, which is accessed by two accessors - set_apicid_to_node() and numa_cpu_node(). On 64bit, numa_cpu_node() always consults __apicid_to_node[] directly while 32bit goes through apic->numa_cpu_node() method to allow apic implementations to override it. srat_detect_node() for amd cpus contains workaround for broken NUMA configuration which assumes relationship between APIC ID, HT node ID and NUMA topology. Leave it to access __apicid_to_node[] directly as mapping through CPU might result in undesirable behavior change. The comment is reformatted and updated to note the ugliness. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Pekka Enberg <penberg@kernel.org> Cc: eric.dumazet@gmail.com Cc: yinghai@kernel.org Cc: brgerst@gmail.com Cc: gorcunov@gmail.com Cc: shaohui.zheng@intel.com Cc: rientjes@google.com LKML-Reference: <1295789862-25482-14-git-send-email-tj@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: David Rientjes <rientjes@google.com>
*---. Merge branches 'softirq-for-linus', 'x86-debug-for-linus', ↵Linus Torvalds2010-10-231-3/+1
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 'x86-numa-for-linus', 'x86-quirks-for-linus', 'x86-setup-for-linus', 'x86-uv-for-linus' and 'x86-vm86-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'softirq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: softirqs: Make wakeup_softirqd static * 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, asm: Restore parentheses around one pushl_cfi argument x86, asm: Fix ancient-GAS workaround x86, asm: Fix CFI macro invocations to deal with shortcomings in gas * 'x86-numa-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, numa: Assign CPUs to nodes in round-robin manner on fake NUMA * 'x86-quirks-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: HPET force enable for CX700 / VIA Epia LT * 'x86-setup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, setup: Use string copy operation to optimze copy in kernel compression * 'x86-uv-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, UV: Use allocated buffer in tlb_uv.c:tunables_read() * 'x86-vm86-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, vm86: Fix preemption bug for int1 debug and int3 breakpoint handlers.
| | * | x86, numa: Assign CPUs to nodes in round-robin manner on fake NUMANikanth Karthikesan2010-10-111-3/+1
| | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit d9c2d5ac6af87b4491bff107113aaf16f6c2b2d9 "x86, numa: Use near(er) online node instead of roundrobin for NUMA" changed NUMA initialization on Intel to choose the nearest online node or first node. Fake NUMA would be better of with round-robin initialization, instead of the all CPUS on first node. Change the choice of first node, back to round-robin. For testing NUMA kernel behaviour without cpusets and NUMA aware applications, it would be better to have cpus in different nodes, rather than all in a single node. With cpusets migration of tasks scenarios cannot not be tested. I guess having it round-robin shouldn't affect the use cases for all cpus on the first node. The code comments in arch/x86/mm/numa_64.c:759 indicate that this used to be the case, which was changed by commit d9c2d5ac6. It changed from roundrobin to nearer or first node. And I couldn't find any reason for this change in its changelog. Signed-off-by: Nikanth Karthikesan <knikanth@suse.de> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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