kernel.git/arch/x86/kernel/smpboot.c, branch linux-3.11.y

x86: delete __cpuinit usage from all x86 files

2013-07-14T23:36:56Z

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 Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: x86@kernel.org Acked-by: Ingo Molnar Acked-by: Thomas Gleixner Acked-by: H. Peter Anvin Signed-off-by: Paul Gortmaker

sched/x86: Construct all sibling maps if smt

2013-05-31T11:10:38Z

Commit 316ad248307fb ("sched/x86: Rewrite set_cpu_sibling_map()") broke the construction of sibling maps, which also broke the booted_cores accounting. Before the rewrite, if smt was present, then each map was updated for each smt sibling. After the rewrite only cpu_sibling_mask gets updated, as the llc and core maps depend on 'has_mc = x86_max_cores > 1' instead. This leads to problems with topologies like the following (qemu -smp sockets=2,cores=1,threads=2) processor : 0 physical id : 0 siblings : 1 <= should be 2 core id : 0 cpu cores : 1 processor : 1 physical id : 0 siblings : 1 <= should be 2 core id : 0 cpu cores : 0 <= should be 1 processor : 2 physical id : 1 siblings : 1 <= should be 2 core id : 0 cpu cores : 1 processor : 3 physical id : 1 siblings : 1 <= should be 2 core id : 0 cpu cores : 0 <= should be 1 This patch restores the former construction by defining has_mc as (has_smt || x86_max_cores > 1). This should be fine as there were no (has_smt && !has_mc) conditions in the context. Aso rename has_mc to has_mp now that it's not just for cores. Signed-off-by: Andrew Jones Acked-by: Peter Zijlstra Cc: a.p.zijlstra@chello.nl Cc: fenghua.yu@intel.com Link: http://lkml.kernel.org/r/1369831695-11970-1-git-send-email-drjones@redhat.com Signed-off-by: Ingo Molnar

x86: Use generic idle loop

2013-04-08T15:39:29Z

Signed-off-by: Thomas Gleixner Cc: Linus Torvalds Cc: Rusty Russell Cc: Paul McKenney Cc: Peter Zijlstra Reviewed-by: Srivatsa S. Bhat Cc: Magnus Damm Link: http://lkml.kernel.org/r/20130321215235.486594473@linutronix.de Signed-off-by: Thomas Gleixner Cc: x86@kernel.org

x86, smpboot: Remove unused variable

2013-03-05T23:26:45Z

The cpuinfo_x86 ptr is unused now. Drop it. Got obsolete by 69fb3676df33 ("x86 idle: remove mwait_idle() and "idle=mwait" cmdline param") removing its only user. [ hpa: fixes gcc warning ] Signed-off-by: Borislav Petkov Link: http://lkml.kernel.org/r/1362428180-8865-2-git-send-email-bp@alien8.de Cc: Len Brown Signed-off-by: H. Peter Anvin

x86 idle: remove mwait_idle() and "idle=mwait" cmdline param

2013-02-10T08:03:41Z

mwait_idle() is a C1-only idle loop intended to be more efficient than HLT, starting on Pentium-4 HT-enabled processors. But mwait_idle() has been replaced by the more general mwait_idle_with_hints(), which handles both C1 and deeper C-states. ACPI processor_idle and intel_idle use only mwait_idle_with_hints(), and no longer use mwait_idle(). Here we simplify the x86 native idle code by removing mwait_idle(), and the "idle=mwait" bootparam used to invoke it. Since Linux 3.0 there has been a boot-time warning when "idle=mwait" was invoked saying it would be removed in 2012. This removal was also noted in the (now removed:-) feature-removal-schedule.txt. After this change, kernels configured with (CONFIG_ACPI=n && CONFIG_INTEL_IDLE=n) when run on hardware that supports MWAIT will simply use HLT. If MWAIT is desired on those systems, cpuidle and the cpuidle drivers above can be enabled. Signed-off-by: Len Brown Cc: x86@kernel.org

Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2012-12-12T03:58:29Z

Pull x86 topology discovery improvements from Ingo Molnar: "These changes improve topology discovery on AMD CPUs. Right now this feeds information displayed in /sys/devices/system/cpu/cpuX/cache/indexY/* - but in the future we could use this to set up a better scheduling topology." * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, cacheinfo: Base cache sharing info on CPUID 0x8000001d on AMD x86, cacheinfo: Make use of CPUID 0x8000001d for cache information on AMD x86, cacheinfo: Determine number of cache leafs using CPUID 0x8000001d on AMD x86: Add cpu_has_topoext

Merge branch 'x86-bsp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2012-12-12T03:56:33Z

Pull x86 BSP hotplug changes from Ingo Molnar: "This tree enables CPU#0 (the boot processor) to be onlined/offlined on x86, just like any other CPU. Enabled on Intel CPUs for now. Allowing this required the identification and fixing of latent CPU#0 assumptions (such as CPU#0 initializations, etc.) in the x86 architecture code, plus the identification of barriers to BSP-offlining, such as active PIC interrupts which can only be serviced on the BSP. It's behind a default-off option, and there's a debug option that allows the automatic testing of this feature. The motivation of this feature is to allow and prepare for true CPU-hotplug hardware support: recent changes to MCE support enable us to detect a deteriorating but not yet hard-failing L1/L2 cache on a CPU that could be soft-unplugged - or a failing L3 cache on a multi-socket system. Note that true hardware hot-plug is not yet fully enabled by this, because that requires a special platform wakeup sequence to be sent to the freshly powered up CPU#0. Future patches for this are planned, once such a platform exists. Chicken and egg" * 'x86-bsp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, topology: Debug CPU0 hotplug x86/i387.c: Initialize thread xstate only on CPU0 only once x86, hotplug: Handle retrigger irq by the first available CPU x86, hotplug: The first online processor saves the MTRR state x86, hotplug: During CPU0 online, enable x2apic, set_numa_node. x86, hotplug: Wake up CPU0 via NMI instead of INIT, SIPI, SIPI x86-32, hotplug: Add start_cpu0() entry point to head_32.S x86-64, hotplug: Add start_cpu0() entry point to head_64.S kernel/cpu.c: Add comment for priority in cpu_hotplug_pm_callback x86, hotplug, suspend: Online CPU0 for suspend or hibernate x86, hotplug: Support functions for CPU0 online/offline x86, topology: Don't offline CPU0 if any PIC irq can not be migrated out of it x86, Kconfig: Add config switch for CPU0 hotplug doc: Add x86 CPU0 online/offline feature

x86, fpu: Avoid FPU lazy restore after suspend

2012-11-30T21:48:05Z

When a cpu enters S3 state, the FPU state is lost. After resuming for S3, if we try to lazy restore the FPU for a process running on the same CPU, this will result in a corrupted FPU context. Ensure that "fpu_owner_task" is properly invalided when (re-)initializing a CPU, so nobody will try to lazy restore a state which doesn't exist in the hardware. Tested with a 64-bit kernel on a 4-core Ivybridge CPU with eagerfpu=off, by doing thousands of suspend/resume cycles with 4 processes doing FPU operations running. Without the patch, a process is killed after a few hundreds cycles by a SIGFPE. Cc: Duncan Laurie Cc: Olof Johansson Cc: v3.4+ # for 3.4 need to replace this_cpu_write by percpu_write Signed-off-by: Vincent Palatin Link: http://lkml.kernel.org/r/1354306532-1014-1-git-send-email-vpalatin@chromium.org Signed-off-by: H. Peter Anvin

x86, hotplug: Wake up CPU0 via NMI instead of INIT, SIPI, SIPI

2012-11-14T23:28:03Z

Instead of waiting for STARTUP after INITs, BSP will execute the BIOS boot-strap code which is not a desired behavior for waking up BSP. To avoid the boot-strap code, wake up CPU0 by NMI instead. This works to wake up soft offlined CPU0 only. If CPU0 is hard offlined (i.e. physically hot removed and then hot added), NMI won't wake it up. We'll change this code in the future to wake up hard offlined CPU0 if real platform and request are available. AP is still waken up as before by INIT, SIPI, SIPI sequence. Signed-off-by: Fenghua Yu Link: http://lkml.kernel.org/r/1352896613-25957-1-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin

x86, hotplug: Support functions for CPU0 online/offline

2012-11-14T17:39:48Z

Add smp_store_boot_cpu_info() to store cpu info for BSP during boot time. Now smp_store_cpu_info() stores cpu info for bringing up BSP or AP after it's offline. Continue to online CPU0 in native_cpu_up(). Continue to offline CPU0 in native_cpu_disable(). Signed-off-by: Fenghua Yu Link: http://lkml.kernel.org/r/1352835171-3958-5-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin