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2010-02-28Merge branch 'master' of /home/davem/src/GIT/linux-2.6/David S. Miller
Conflicts: drivers/firmware/iscsi_ibft.c
2010-02-28Merge branch 'x86-uv-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-uv-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, uv: Remove recursion in uv_heartbeat_enable() x86, uv: uv_global_gru_mmr_address() macro fix x86, uv: Add serial number parameter to uv_bios_get_sn_info()
2010-02-28Merge branch 'x86-ptrace-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-ptrace-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, ptrace: Remove set_stopped_child_used_math() in [x]fpregs_set x86, ptrace: Simplify xstateregs_get() ptrace: Fix ptrace_regset() comments and diagnose errors specifically parisc: Disable CONFIG_HAVE_ARCH_TRACEHOOK ptrace: Add support for generic PTRACE_GETREGSET/PTRACE_SETREGSET x86, ptrace: regset extensions to support xstate
2010-02-28Merge branch 'x86-pci-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-pci-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Enable NMI on all cpus on UV vgaarb: Add user selectability of the number of GPUS in a system vgaarb: Fix VGA arbiter to accept PCI domains other than 0 x86, uv: Update UV arch to target Legacy VGA I/O correctly. pci: Update pci_set_vga_state() to call arch functions
2010-02-28Merge branch 'x86-setup-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-setup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, setup: Don't skip mode setting for the standard VGA modes x86-64, setup: Inhibit decompressor output if video info is invalid x86, setup: When restoring the screen, update boot_params.screen_info
2010-02-28Merge branch 'x86-rwsem-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-rwsem-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86-64, rwsem: Avoid store forwarding hazard in __downgrade_write x86-64, rwsem: 64-bit xadd rwsem implementation x86: Fix breakage of UML from the changes in the rwsem system x86-64: support native xadd rwsem implementation x86: clean up rwsem type system
2010-02-28Merge branch 'x86-numa-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-numa-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, numa: Remove configurable node size support for numa emulation x86, numa: Add fixed node size option for numa emulation x86, numa: Fix numa emulation calculation of big nodes x86, acpi: Map hotadded cpu to correct node.
2010-02-28Merge branch 'x86-mtrr-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-mtrr-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Convert set_atomicity_lock to raw_spinlock x86, mtrr: Kill over the top warn x86, mtrr: Constify struct mtrr_ops
2010-02-28Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, mm: Unify kernel_physical_mapping_init() API x86, mm: Allow highmem user page tables to be disabled at boot time x86: Do not reserve brk for DMI if it's not going to be used x86: Convert tlbstate_lock to raw_spinlock x86: Use the generic page_is_ram() x86: Remove BIOS data range from e820 Move page_is_ram() declaration to mm.h Generic page_is_ram: use __weak resources: introduce generic page_is_ram()
2010-02-28Merge branch 'x86-io-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-io-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Merge io.h x86: Simplify flush_write_buffers() x86: Clean up mem*io functions. x86-64: Use BUILDIO in io_64.h x86-64: Reorganize io_64.h x86-32: Remove _local variants of in/out from io_32.h x86-32: Move XQUAD definitions to numaq.h
2010-02-28Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds
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, cacheinfo: Enable L3 CID only on AMD x86, cacheinfo: Remove NUMA dependency, fix for AMD Fam10h rev D1 x86, cpu: Print AMD virtualization features in /proc/cpuinfo x86, cacheinfo: Calculate L3 indices x86, cacheinfo: Add cache index disable sysfs attrs only to L3 caches x86, cacheinfo: Fix disabling of L3 cache indices intel-agp: Switch to wbinvd_on_all_cpus x86, lib: Add wbinvd smp helpers
2010-02-28Merge branch 'x86-cleanups-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Remove trailing spaces in messages x86, mtrr: Remove unused mtrr/state.c x86, trivial: Fix grammo in tsc comment about Geode TSC reliability
2010-02-28Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Mark atomic irq ops raw for 32bit legacy x86: Merge show_regs() x86: Macroise x86 cache descriptors x86-32: clean up rwsem inline asm statements x86: Merge asm/atomic_{32,64}.h x86: Sync asm/atomic_32.h and asm/atomic_64.h x86: Split atomic64_t functions into seperate headers x86-64: Modify memcpy()/memset() alternatives mechanism x86-64: Modify copy_user_generic() alternatives mechanism x86: Lift restriction on the location of FIX_BTMAP_* x86, core: Optimize hweight32()
2010-02-28Merge branch 'perf-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (172 commits) perf_event, amd: Fix spinlock initialization perf_event: Fix preempt warning in perf_clock() perf tools: Flush maps on COMM events perf_events, x86: Split PMU definitions into separate files perf annotate: Handle samples not at objdump output addr boundaries perf_events, x86: Remove superflous MSR writes perf_events: Simplify code by removing cpu argument to hw_perf_group_sched_in() perf_events, x86: AMD event scheduling perf_events: Add new start/stop PMU callbacks perf_events: Report the MMAP pgoff value in bytes perf annotate: Defer allocating sym_priv->hist array perf symbols: Improve debugging information about symtab origins perf top: Use a macro instead of a constant variable perf symbols: Check the right return variable perf/scripts: Tag syscall_name helper as not yet available perf/scripts: Add perf-trace-python Documentation perf/scripts: Remove unnecessary PyTuple resizes perf/scripts: Add syscall tracing scripts perf/scripts: Add Python scripting engine perf/scripts: Remove check-perf-trace from listed scripts ... Fix trivial conflict in tools/perf/util/probe-event.c
2010-02-28Merge branch 'tracing-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (28 commits) ftrace: Add function names to dangling } in function graph tracer tracing: Simplify memory recycle of trace_define_field tracing: Remove unnecessary variable in print_graph_return tracing: Fix typo of info text in trace_kprobe.c tracing: Fix typo in prof_sysexit_enable() tracing: Remove CONFIG_TRACE_POWER from kernel config tracing: Fix ftrace_event_call alignment for use with gcc 4.5 ftrace: Remove memory barriers from NMI code when not needed tracing/kprobes: Add short documentation for HAVE_REGS_AND_STACK_ACCESS_API s390: Add pt_regs register and stack access API tracing/kprobes: Make Kconfig dependencies generic tracing: Unify arch_syscall_addr() implementations tracing: Add notrace to TRACE_EVENT implementation functions ftrace: Allow to remove a single function from function graph filter tracing: Add correct/incorrect to sort keys for branch annotation output tracing: Simplify test for function_graph tracing start point tracing: Drop the tr check from the graph tracing path tracing: Add stack dump to trace_printk if stacktrace option is set tracing: Use appropriate perl constructs in recordmcount.pl tracing: optimize recordmcount.pl for offsets-handling ...
2010-02-28Merge branch 'oprofile-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'oprofile-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: oprofile/x86: fix msr access to reserved counters oprofile/x86: use kzalloc() instead of kmalloc() oprofile/x86: fix perfctr nmi reservation for mulitplexing oprofile/x86: add comment to counter-in-use warning oprofile/x86: warn user if a counter is already active oprofile/x86: implement randomization for IBS periodic op counter oprofile/x86: implement lsfr pseudo-random number generator for IBS oprofile/x86: implement IBS cpuid feature detection oprofile/x86: remove node check in AMD IBS initialization oprofile/x86: remove OPROFILE_IBS config option oprofile: remove EXPERIMENTAL from the config option description oprofile: remove tracing build dependency
2010-02-28Merge branches 'core-ipi-for-linus', 'core-locking-for-linus', ↵Linus Torvalds
'tracing-fixes-for-linus', 'x86-debug-for-linus', 'x86-doc-for-linus', 'x86-gpu-for-linus' and 'x86-rlimit-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-ipi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: generic-ipi: Optimize accesses by using DEFINE_PER_CPU_SHARED_ALIGNED for IPI data * 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: plist: Fix grammar mistake, and c-style mistake * 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: kprobes: Add mcount to the kprobes blacklist * 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86_64: Print modules like i386 does * 'x86-doc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Put 'nopat' in kernel-parameters * 'x86-gpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86-64: Allow fbdev primary video code * 'x86-rlimit-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Use helpers for rlimits
2010-02-27x86: Enable NMI on all cpus on UVRuss Anderson
Enable NMI on all cpus in UV system and add an NMI handler to dump_stack on each cpu. By default on x86 all the cpus except the boot cpu have NMI masked off. This patch enables NMI on all cpus in UV system and adds an NMI handler to dump_stack on each cpu. This way if a system hangs we can NMI the machine and get a backtrace from all the cpus. Version 2: Use x86_platform driver mechanism for nmi init, per Ingo's suggestion. Version 3: Clean up Ingo's nits. Signed-off-by: Russ Anderson <rja@sgi.com> LKML-Reference: <20100226164912.GA24439@sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-27Merge branch 'tracing/core' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into tracing/core
2010-02-26Merge branch 'kmemcheck-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6 * 'kmemcheck-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6: kmemcheck: Test the full object in kmemcheck_is_obj_initialized()
2010-02-26Merge branch 'kmemcheck/fixes' into kmemcheck-for-linusPekka Enberg
2010-02-26perf_event, amd: Fix spinlock initializationPeter Zijlstra
Avoid kernels from exploding on AMD machines when they have any lock debugging bits enabled. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-26perf_events, x86: Split PMU definitions into separate filesPeter Zijlstra
Split amd,p6,intel into separate files so that we can easily deal with CONFIG_CPU_SUP_* things, needed to make things build now that perf_event.c relies on symbols from amd.c Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-26oprofile/x86: fix msr access to reserved countersRobert Richter
During switching virtual counters there is access to perfctr msrs. If the counter is not available this fails due to an invalid address. This patch fixes this. Cc: stable@kernel.org Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-02-26oprofile/x86: use kzalloc() instead of kmalloc()Robert Richter
Cc: stable@kernel.org Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-02-26oprofile/x86: fix perfctr nmi reservation for mulitplexingRobert Richter
Multiple virtual counters share one physical counter. The reservation of virtual counters fails due to duplicate allocation of the same counter. The counters are already reserved. Thus, virtual counter reservation may removed at all. This also makes the code easier. Cc: stable@kernel.org Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-02-26oprofile/x86: add comment to counter-in-use warningNaga Chumbalkar
Currently, oprofile fails silently on platforms where a non-OS entity such as the system firmware "enables" and uses a performance counter. There is a warning in the code for this case. The warning indicates an already running counter. If oprofile doesn't collect data, then try using a different performance counter on your platform to monitor the desired event. Delete the counter from the desired event by editing the /usr/share/oprofile/<cpu_type>/<cpu>/events file. If the event cannot be monitored by any other counter, contact your hardware or BIOS vendor. Cc: Shashi Belur <shashi-kiran.belur@hp.com> Cc: Tony Jones <tonyj@suse.de> Signed-off-by: Naga Chumbalkar <nagananda.chumbalkar@hp.com> Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-02-26oprofile/x86: warn user if a counter is already activeRobert Richter
This patch generates a warning if a counter is already active. Implemented for AMD and P6 models. P4 is not supported. Cc: Naga Chumbalkar <nagananda.chumbalkar@hp.com> Cc: Shashi Belur <shashi-kiran.belur@hp.com> Cc: Tony Jones <tonyj@suse.de> Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-02-26oprofile/x86: implement randomization for IBS periodic op counterRobert Richter
IBS selects an op (execution operation) for sampling by counting either cycles or dispatched ops. Better statistical samples can be produced by adding a software generated random offset to the periodic op counter value with each sample. This patch adds software randomization to the IBS periodic op counter. The lower 12 bits of the 20 bit counter are randomized. IbsOpCurCnt is initialized with a 12 bit random value. There is a work around if the hw can not write to IbsOpCurCnt. Then the lower 8 bits of the 16 bit IbsOpMaxCnt [15:0] value are randomized in the range of -128 to +127 by adding/subtracting an offset to the maximum count (IbsOpMaxCnt). The linear feedback shift register (LFSR) algorithm is used for pseudo-random number generation to have low impact to the memory system. Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-02-26oprofile/x86: implement lsfr pseudo-random number generator for IBSSuravee Suthikulpanit
This patch implements a linear feedback shift register (LFSR) for pseudo-random number generation for IBS. For IBS measurements it would be good to minimize memory traffic in the interrupt handler since every access pollutes the data caches. Computing a maximal period LFSR just needs shifts and ORs. The LFSR method is good enough to randomize the ops at low overhead. 16 pseudo-random bits are enough for the implementation and it doesn't matter that the pattern repeats with a fairly short cycle. It only needs to break up (hard) periodic sampling behavior. The logic was designed by Paul Drongowski. Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-02-26oprofile/x86: implement IBS cpuid feature detectionRobert Richter
This patch adds IBS feature detection using cpuid flags. An IBS capability mask is introduced to test for certain IBS features. The bit mask is the same as for IBS cpuid feature flags (Fn8000_001B_EAX), but bit 0 is used to indicate the existence of IBS. The patch also changes the handling of the IbsOpCntCtl bit (periodic op counter count control). The oprofilefs file for this feature (ibs_op/dispatched_ops) will be only exposed if the feature is available, also the default for the bit is set to count clock cycles. In general, the userland can detect the availability of a feature by checking for the corresponding file in oprofilefs. If it exists, the feature also exists. This may lead to a dynamic file layout depending on the cpu type with that the userland has to deal with. Current opcontrol is compatible. Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-02-26oprofile/x86: remove node check in AMD IBS initializationRobert Richter
Standard AMD systems have the same number of nodes as there are northbridge devices. However, there may kernel configurations (especially for 32 bit) or system setups exist, where the node number is different or it can not be detected properly. Thus the check is not reliable and may fail though IBS setup was fine. For this reason it is better to remove the check. Cc: stable <stable@kernel.org> Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-02-26oprofile/x86: remove OPROFILE_IBS config optionRobert Richter
OProfile support for IBS is now for several versions in the kernel. The feature is stable now and the code can be activated permanently. As a side effect IBS now works also on nosmp configs. Signed-off-by: Robert Richter <robert.richter@amd.com>
2010-02-26perf_events, x86: Remove superflous MSR writesPeter Zijlstra
We re-program the event control register every time we reset the count, this appears to be superflous, hence remove it. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arjan van de Ven <arjan@linux.intel.com> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-26perf_events: Simplify code by removing cpu argument to hw_perf_group_sched_in()Peter Zijlstra
Since the cpu argument to hw_perf_group_sched_in() is always smp_processor_id(), simplify the code a little by removing this argument and using the current cpu where needed. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: David Miller <davem@davemloft.net> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1265890918.5396.3.camel@laptop> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-26perf_events, x86: AMD event schedulingStephane Eranian
This patch adds correct AMD NorthBridge event scheduling. NB events are events measuring L3 cache, Hypertransport traffic. They are identified by an event code >= 0xe0. They measure events on the Northbride which is shared by all cores on a package. NB events are counted on a shared set of counters. When a NB event is programmed in a counter, the data actually comes from a shared counter. Thus, access to those counters needs to be synchronized. We implement the synchronization such that no two cores can be measuring NB events using the same counters. Thus, we maintain a per-NB allocation table. The available slot is propagated using the event_constraint structure. Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <4b703957.0702d00a.6bf2.7b7d@mx.google.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-26perf_events: Add new start/stop PMU callbacksStephane Eranian
In certain situations, the kernel may need to stop and start the same event rapidly. The current PMU callbacks do not distinguish between stop and release (i.e., stop + free the resource). Thus, a counter may be released, then it will be immediately re-acquired. Event scheduling will again take place with no guarantee to assign the same counter. On some processors, this may event yield to failure to assign the event back due to competion between cores. This patch is adding a new pair of callback to stop and restart a counter without actually release the underlying counter resource. On stop, the counter is stopped, its values saved and that's it. On start, the value is reloaded and counter is restarted (on x86, actual restart is delayed until perf_enable()). Signed-off-by: Stephane Eranian <eranian@google.com> [ added fallback to ->enable/->disable for all other PMUs fixed x86_pmu_start() to call x86_pmu.enable() merged __x86_pmu_disable into x86_pmu_stop() ] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <4b703875.0a04d00a.7896.ffffb824@mx.google.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-26Merge branch 'tip/tracing/core' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into tracing/core
2010-02-25x86, mm: Unify kernel_physical_mapping_init() APIPekka Enberg
This patch changes the 32-bit version of kernel_physical_mapping_init() to return the last mapped address like the 64-bit one so that we can unify the call-site in init_memory_mapping(). Cc: Yinghai Lu <yinghai@kernel.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> LKML-Reference: <alpine.DEB.2.00.1002241703570.1180@melkki.cs.helsinki.fi> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-25x86/PCI: Prevent mmconfig memory corruptionThomas Gleixner
commit ff097ddd4 (x86/PCI: MMCONFIG: manage pci_mmcfg_region as a list, not a table) introduced a nasty memory corruption when pci_mmcfg_list is empty. pci_mmcfg_check_end_bus_number() dereferences pci_mmcfg_list.prev even when the list is empty. The following write hits some variable near to pci_mmcfg_list. Further down a similar problem exists, where cfg->list.next is dereferenced unconditionally and a comparison with some variable near to pci_mmcfg_list happens. Add a check for the last element into the for_each_entry() loop and remove all the other crappy logic which is just a leftover of the old array based code which was replaced by the list conversion. Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: stable@kernel.org Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-02-25ftrace: Remove memory barriers from NMI code when not neededSteven Rostedt
The code in stop_machine that modifies the kernel text has a bit of logic to handle the case of NMIs. stop_machine does not prevent NMIs from executing, and if an NMI were to trigger on another CPU as the modifying CPU is changing the NMI text, a GPF could result. To prevent the GPF, the NMI calls ftrace_nmi_enter() which may modify the code first, then any other NMIs will just change the text to the same content which will do no harm. The code that stop_machine called must wait for NMIs to finish while it changes each location in the kernel. That code may also change the text to what the NMI changed it to. The key is that the text will never change content while another CPU is executing it. To make the above work, the call to ftrace_nmi_enter() must also do a smp_mb() as well as atomic_inc(). But for applications like perf that require a high number of NMIs for profiling, this can have a dramatic effect on the system. Not only is it doing a full memory barrier on both nmi_enter() as well as nmi_exit() it is also modifying a global variable with an atomic operation. This kills performance on large SMP machines. Since the memory barriers are only needed when ftrace is in the process of modifying the text (which is seldom), this patch adds a "modifying_code" variable that gets set before stop machine is executed and cleared afterwards. The NMIs will check this variable and store it in a per CPU "save_modifying_code" variable that it will use to check if it needs to do the memory barriers and atomic dec on NMI exit. Acked-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-02-25x86, mm: Allow highmem user page tables to be disabled at boot timeIan Campbell
Distros generally (I looked at Debian, RHEL5 and SLES11) seem to enable CONFIG_HIGHPTE for any x86 configuration which has highmem enabled. This means that the overhead applies even to machines which have a fairly modest amount of high memory and which therefore do not really benefit from allocating PTEs in high memory but still pay the price of the additional mapping operations. Running kernbench on a 4G box I found that with CONFIG_HIGHPTE=y but no actual highptes being allocated there was a reduction in system time used from 59.737s to 55.9s. With CONFIG_HIGHPTE=y and highmem PTEs being allocated: Average Optimal load -j 4 Run (std deviation): Elapsed Time 175.396 (0.238914) User Time 515.983 (5.85019) System Time 59.737 (1.26727) Percent CPU 263.8 (71.6796) Context Switches 39989.7 (4672.64) Sleeps 42617.7 (246.307) With CONFIG_HIGHPTE=y but with no highmem PTEs being allocated: Average Optimal load -j 4 Run (std deviation): Elapsed Time 174.278 (0.831968) User Time 515.659 (6.07012) System Time 55.9 (1.07799) Percent CPU 263.8 (71.266) Context Switches 39929.6 (4485.13) Sleeps 42583.7 (373.039) This patch allows the user to control the allocation of PTEs in highmem from the command line ("userpte=nohigh") but retains the status-quo as the default. It is possible that some simple heuristic could be developed which allows auto-tuning of this option however I don't have a sufficiently large machine available to me to perform any particularly meaningful experiments. We could probably handwave up an argument for a threshold at 16G of total RAM. Assuming 768M of lowmem we have 196608 potential lowmem PTE pages. Each page can map 2M of RAM in a PAE-enabled configuration, meaning a maximum of 384G of RAM could potentially be mapped using lowmem PTEs. Even allowing generous factor of 10 to account for other required lowmem allocations, generous slop to account for page sharing (which reduces the total amount of RAM mappable by a given number of PT pages) and other innacuracies in the estimations it would seem that even a 32G machine would not have a particularly pressing need for highmem PTEs. I think 32G could be considered to be at the upper bound of what might be sensible on a 32 bit machine (although I think in practice 64G is still supported). It's seems questionable if HIGHPTE is even a win for any amount of RAM you would sensibly run a 32 bit kernel on rather than going 64 bit. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> LKML-Reference: <1266403090-20162-1-git-send-email-ian.campbell@citrix.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-25x86: Do not reserve brk for DMI if it's not going to be usedThadeu Lima de Souza Cascardo
This will save 64K bytes from memory when loading linux if DMI is disabled, which is good for embedded systems. Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com> LKML-Reference: <1265758732-19320-1-git-send-email-cascardo@holoscopio.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-23x86, ptrace: Remove set_stopped_child_used_math() in [x]fpregs_setSuresh Siddha
init_fpu() already ensures that the used_math() is set for the stopped child. Remove the redundant set_stopped_child_used_math() in [x]fpregs_set() Reported-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> LKML-Reference: <20100222225240.642169080@sbs-t61.sc.intel.com> Acked-by: Rolan McGrath <roland@redhat.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-23x86, ptrace: Simplify xstateregs_get()Suresh Siddha
48 bytes (bytes 464..511) of the xstateregs payload come from the kernel defined structure (xstate_fx_sw_bytes). Rest comes from the xstate regs structure in the thread struct. Instead of having multiple user_regset_copyout()'s, simplify the xstateregs_get() by first copying the SW bytes into the xstate regs structure in the thread structure and then using one user_regset_copyout() to copyout the xstateregs. Requested-by: Roland McGrath <roland@redhat.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> LKML-Reference: <20100222225240.494688491@sbs-t61.sc.intel.com> Acked-by: Roland McGrath <roland@redhat.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: Oleg Nesterov <oleg@redhat.com>
2010-02-23x86/PCI: use host bridge _CRS info by default on 2008 and newer machinesBjorn Helgaas
The main benefit of using ACPI host bridge window information is that we can do better resource allocation in systems with multiple host bridges, e.g., http://bugzilla.kernel.org/show_bug.cgi?id=14183 Sometimes we need _CRS information even if we only have one host bridge, e.g., https://bugs.launchpad.net/ubuntu/+source/linux/+bug/341681 Most of these systems are relatively new, so this patch turns on "pci=use_crs" only on machines with a BIOS date of 2008 or newer. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-02-23PCI: augment bus resource table with a listBjorn Helgaas
Previously we used a table of size PCI_BUS_NUM_RESOURCES (16) for resources forwarded to a bus by its upstream bridge. We've increased this size several times when the table overflowed. But there's no good limit on the number of resources because host bridges and subtractive decode bridges can forward any number of ranges to their secondary buses. This patch reduces the table to only PCI_BRIDGE_RESOURCE_NUM (4) entries, which corresponds to the number of windows a PCI-to-PCI (3) or CardBus (4) bridge can positively decode. Any additional resources, e.g., PCI host bridge windows or subtractively-decoded regions, are kept in a list. I'd prefer a single list rather than this split table/list approach, but that requires simultaneous changes to every architecture. This approach only requires immediate changes where we set up (a) host bridges with more than four windows and (b) subtractive-decode P2P bridges, and we can incrementally change other architectures to use the list. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-02-22resource/PCI: mark struct resource as constDominik Brodowski
Now that we return the new resource start position, there is no need to update "struct resource" inside the align function. Therefore, mark the struct resource as const. Cc: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-02-22resource/PCI: align functions now return start of resourceDominik Brodowski
As suggested by Linus, align functions should return the start of a resource, not void. An update of "res->start" is no longer necessary. Cc: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-02-22x86/PCI: irq and pci_ids patch for Intel Cougar Point DeviceIDsSeth Heasley
This patch adds the Intel Cougar Point (PCH) LPC and SMBus Controller DeviceIDs. Signed-off-by: Seth Heasley <seth.heasley@intel.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>