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2014-01-20Merge branch 'sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler changes from Ingo Molnar: - Add the initial implementation of SCHED_DEADLINE support: a real-time scheduling policy where tasks that meet their deadlines and periodically execute their instances in less than their runtime quota see real-time scheduling and won't miss any of their deadlines. Tasks that go over their quota get delayed (Available to privileged users for now) - Clean up and fix preempt_enable_no_resched() abuse all around the tree - Do sched_clock() performance optimizations on x86 and elsewhere - Fix and improve auto-NUMA balancing - Fix and clean up the idle loop - Apply various cleanups and fixes * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (60 commits) sched: Fix __sched_setscheduler() nice test sched: Move SCHED_RESET_ON_FORK into attr::sched_flags sched: Fix up attr::sched_priority warning sched: Fix up scheduler syscall LTP fails sched: Preserve the nice level over sched_setscheduler() and sched_setparam() calls sched/core: Fix htmldocs warnings sched/deadline: No need to check p if dl_se is valid sched/deadline: Remove unused variables sched/deadline: Fix sparse static warnings m68k: Fix build warning in mac_via.h sched, thermal: Clean up preempt_enable_no_resched() abuse sched, net: Fixup busy_loop_us_clock() sched, net: Clean up preempt_enable_no_resched() abuse sched/preempt: Fix up missed PREEMPT_NEED_RESCHED folding sched/preempt, locking: Rework local_bh_{dis,en}able() sched/clock, x86: Avoid a runtime condition in native_sched_clock() sched/clock: Fix up clear_sched_clock_stable() sched/clock, x86: Use a static_key for sched_clock_stable sched/clock: Remove local_irq_disable() from the clocks sched/clock, x86: Rewrite cyc2ns() to avoid the need to disable IRQs ...
2014-01-20Merge branch 'core-locking-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core locking changes from Ingo Molnar: - futex performance increases: larger hashes, smarter wakeups - mutex debugging improvements - lots of SMP ordering documentation updates - introduce the smp_load_acquire(), smp_store_release() primitives. (There are WIP patches that make use of them - not yet merged) - lockdep micro-optimizations - lockdep improvement: better cover IRQ contexts - liblockdep at last. We'll continue to monitor how useful this is * 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits) futexes: Fix futex_hashsize initialization arch: Re-sort some Kbuild files to hopefully help avoid some conflicts futexes: Avoid taking the hb->lock if there's nothing to wake up futexes: Document multiprocessor ordering guarantees futexes: Increase hash table size for better performance futexes: Clean up various details arch: Introduce smp_load_acquire(), smp_store_release() arch: Clean up asm/barrier.h implementations using asm-generic/barrier.h arch: Move smp_mb__{before,after}_atomic_{inc,dec}.h into asm/atomic.h locking/doc: Rename LOCK/UNLOCK to ACQUIRE/RELEASE mutexes: Give more informative mutex warning in the !lock->owner case powerpc: Full barrier for smp_mb__after_unlock_lock() rcu: Apply smp_mb__after_unlock_lock() to preserve grace periods Documentation/memory-barriers.txt: Downgrade UNLOCK+BLOCK locking: Add an smp_mb__after_unlock_lock() for UNLOCK+BLOCK barrier Documentation/memory-barriers.txt: Document ACCESS_ONCE() Documentation/memory-barriers.txt: Prohibit speculative writes Documentation/memory-barriers.txt: Add long atomic examples to memory-barriers.txt Documentation/memory-barriers.txt: Add needed ACCESS_ONCE() calls to memory-barriers.txt Revert "smp/cpumask: Make CONFIG_CPUMASK_OFFSTACK=y usable without debug dependency" ...
2014-01-19m68k/mac: Make SCC reset work more reliablyFinn Thain
For SCC initialization we cannot assume that the control register is in the correct state to accept a register pointer. So first read from the control register in order to "sync" up. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2014-01-16m68k: Fix build warning in mac_via.hPeter Zijlstra
Fengguang Wu's kbuild test robot reported the following new m68k warnings: In file included from drivers/nubus/nubus.c:22:0: >> arch/m68k/include/asm/mac_via.h:262:47: warning: 'struct irq_desc' declared inside parameter list [enabled by default] >> arch/m68k/include/asm/mac_via.h:262:47: warning: its scope is only this definition or declaration, which is probably not what you want [enabled by default] Caused by the reworking of the generic local_bh{dis,en}able() code. To fix it, forward declare 'struct irq_desc'. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Fixes: c795eb55e740 ("sched/preempt, locking: Rework local_bh_{dis,en}able()") Signed-off-by: Peter Zijlstra <peterz@infradead.org> Acked-by: geert@linux-m68k.org Link: http://lkml.kernel.org/r/20140112212456.GQ7572@laptop.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-01-13m68k/irq - Use polled IRQ flag for MFP timer cascaded interruptsMichael Schmitz
Some Atari hardware has no capacity to raise interrupts (e.g. network or USB adapter hardware attached via ROM port). The driver interrupt routine is called from a timer interrupt (timer D) in these cases, using chained device specific pseudo interrupts (IRQ_MFP_TIMER1 ff.) These interrupts will more often than not, return IRQ_NONE as there is not always work for the device handler when called. Too many unhandled interrupts will result in the interrupt being disabled by the stuck interrupt watchdog. As preferred option to flag interrupts as needing exclusion from the watchdog mechanism, tglx added the IRQ_IS_POLLED flag for use in such a case. Currently, two interrupts need to use this flag. Add more users as needed. Signed-off-by: Michael Schmitz <schmitz@debian.org> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2014-01-12arch: Clean up asm/barrier.h implementations using asm-generic/barrier.hPeter Zijlstra
We're going to be adding a few new barrier primitives, and in order to avoid endless duplication make more agressive use of asm-generic/barrier.h. Change the asm-generic/barrier.h such that it allows partial barrier definitions and fills out the rest with defaults. There are a few architectures (m32r, m68k) that could probably do away with their barrier.h file entirely but are kept for now due to their unconventional nop() implementation. Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Michael Neuling <mikey@neuling.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Victor Kaplansky <VICTORK@il.ibm.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/r/20131213150640.846368594@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-12-30m68k: Update defconfigs for v3.13-rc1Geert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-12-30m68k/defconfig: Enable EARLY_PRINTKGeert Uytterhoeven
It's too valuable for debugging to be disabled. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-12-30m68k/mm: kmap spelling/grammar fixesGeert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-12-30m68k: Convert arch/m68k/kernel/traps.c to pr_*()Geert Uytterhoeven
Also fix a few printf-style formats, to get rid of the following compiler warnings when DEBUG is enabled: arch/m68k/kernel/traps.c: In function ‘access_error060’: arch/m68k/kernel/traps.c:166: warning: format ‘%d’ expects type ‘int’, but argument 2 has type ‘long unsigned int’ arch/m68k/kernel/traps.c: In function ‘bus_error030’: arch/m68k/kernel/traps.c:568: warning: format ‘%#lx’ expects type ‘long unsigned int’, but argument 2 has type ‘void *’ arch/m68k/kernel/traps.c:682: warning: format ‘%#lx’ expects type ‘long unsigned int’, but argument 2 has type ‘void *’ Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-12-30m68k: Convert arch/m68k/mm/fault.c to pr_*()Geert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-12-30m68k/mm: Check for mm != NULL in do_page_fault() debug codeGeert Uytterhoeven
When DEBUG is enabled, do_page_fault() may dereference a NULL pointer, causing recursive bus errors. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-12-30m68k/defconfig: Disable /sbin/hotplug fork-bomb by defaultGeert Uytterhoeven
Cfr. commit 7934779a69f1184f29d786b89e77dd14519bd226 ("Driver-Core: disable /sbin/hotplug by default"). Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-12-08m68k/atari: Hide RTC_PORT() macro from rtc-cmosGeert Uytterhoeven
Rename RTC_PORT() to ATARI_RTC_PORT(), as the rtc-cmos RTC driver uses the presence of this macro to enable support for the second NVRAM bank, which Atari doesn't have ("Unable to handle kernel access at virtual address 00ff8965"). Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-12-08m68k/amiga,atari: Fix specifying multiple debug= parametersGeert Uytterhoeven
Since commit d6713b4091a99fa2af2fabdcd2f3fb97f32ecf2e ("m68k: early parameter support"), the user can specify multiple debug consoles using the "debug=" kernel command line parameter. However, as there's only a single struct console object, which is reused, it would actually register the same console object multiple times, causing the following warning: WARNING: CPU: 0 PID: 0 at kernel/printk/printk.c:2233 register_console+0x36/ console 'debug0' already registered Make sure to register the console object only once, to avoid the warning. Note that still only one console (the one corresponding to the last "debug=" parameter) will be active at the same time, as the .write() method of the already registered console object is overwritten by a subsequent "debug=" parameter. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-12-08m68k/defconfig: Use ext4 for ext2/ext3 file systemsGeert Uytterhoeven
This reduces the kernel image size by ca. 160 KiB. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-12-08m68k: Add support to export bootinfo in procfsGeert Uytterhoeven
Add optional support to export the bootinfo used to boot the kernel in a "bootinfo" file in procfs. This is useful with kexec. This is based on the similar feature for ATAGS on ARM. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-12-08m68k: Add kexec supportGeert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k/amiga: Provide mach_random_get_entropy()Geert Uytterhoeven
Use the beam position registers, which provide at least 17 bits of data changing at 1.79 MHz. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k: Add infrastructure for machine-specific random_get_entropy()Geert Uytterhoeven
On m68k, get_cycles() (the default implementation for random_get_entropy()) always returns zero, providing no entropy for the random driver. Add a hook where platforms can provide their own implementation, and wire it up in the infrastructure provided by commit 61875f30daf60305712e25b209ef41ced2635bad ("random: allow architectures to optionally define random_get_entropy()"). Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k/atari: Call paging_init() before nf_init()Geert Uytterhoeven
nf_init() uses virt_to_phys(), which depends on m68k_memoffset being set and module_fixup() having been called, but this is only done in paging_init(). Hence call paging_init() before nf_init(). This went unnoticed, as virt_to_phys() is a no-op on Atari, unless you start fiddling with the memory blocks in the bootinfo manually. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k: Remove superfluous inclusions of <asm/bootinfo.h>Geert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k/UAPI: Use proper types (endianness/size) in <asm/bootinfo*.h>Geert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k/UAPI: Move VME Board ID definition to <asm/bootinfo-vme.h>Geert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k/UAPI: Move Macintosh model definitions to <asm/bootinfo-mac.h>Geert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k/UAPI: Move HP300 model definitions to <asm/bootinfo-hp300.h>Geert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k/UAPI: Move Apollo model definitions to <asm/bootinfo-apollo.h>Geert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k/UAPI: Move Amiga model/chipset definitions to <asm/bootinfo-amiga.h>Geert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k/UAPI: Move generic definitions to <asm/bootinfo.h>Geert Uytterhoeven
Move generic definitions used by bootstraps to uapi/asm/bootinfo.h: - Machine types, - CPU, FPU, and MMU types, - struct mem_info. Keep a copy of struct mem_info for in-kernel use, and rename it to struct m68k_mem_info, as the exported one will be modified later. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k/UAPI: Disintegrate arch/m68k/include/asm/bootinfo.hGeert Uytterhoeven
Export the bootinfo definitions that are used by bootstrap loaders, and split them up in generic and platform-specific parts. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k/vme: Remove unused mvme_bdid_ptrGeert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k/mac: Move struct mac_booter_data to <asm/macintosh.h>Geert Uytterhoeven
struct mac_booter_data is no longer part of the bootinfo API, hence move it from <asm/bootinfo.h> to <asm/macintosh.h>, dropping all unused fields in the process. Also remove the no longer used mac_booter_data pointer from head.S. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k: Drop remainings and API of BOOTINFO_COMPAT_1_0Geert Uytterhoeven
Drop remainings and API for backwards compatibility with bootinfo interface version 1.0. This was used when booting a 2.1.x or newer kernel on Amiga, Atari, or Mac using a bootstrap for kernel 2.0.x. Everybody upgraded his bootstrap a long time ago, so this can go. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k: head.S - Correct date and spellingGeert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k: The bootinfo is located right after the kernelGeert Uytterhoeven
Since the introduction of init sections (which are located after BSS), the bootinfo is no longer located right after the BSS, but after all kernel sections. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26zorro/UAPI: Use proper types (endianness/size) in <linux/zorro.h>Geert Uytterhoeven
Fix member definitions for non-native userspace handling: - All multi-byte values are big-endian, hence use __be*, - All pointers are 32-bit pointers under AmigaOS, but unused (except for cd_BoardAddr) under Linux, hence use __be32. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26zorro: ZTWO_VADDR() should return "void __iomem *"Geert Uytterhoeven
ZTWO_VADDR() converts from physical to virtual I/O addresses, so it should return "void __iomem *" instead of "unsigned long". This allows to drop several casts, but requires adding a few casts to accomodate legacy driver frameworks that store "unsigned long" I/O addresses. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26zorro: Do not allocate zorro_autocon[] staticallyGeert Uytterhoeven
Currently the array of Zorro devices is allocated statically, wasting up to 4.5 KiB when running an Amiga or multi-platform kernel on a machine with no or a handful of Zorro expansion cards. Convert it to conditional dynamic memory allocation to fix this. amiga_parse_bootinfo() still needs to store some information about the detected Zorro devices, at a time even the bootmem allocator is not yet available. This is now handled using a much smaller array (typically less than 0.5 KiB), which is __initdata and thus freed later. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k/setup: Use pr_*() and __func__ instead of plain printk()Geert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k/defconfig: Make NFS_V4 modular instead of builtinGeert Uytterhoeven
This reduces the kernel image size by ca. 100 KiB, while still allowing NFS root. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k/mac: Fix comment about iop_*_present flags setup timingGeert Uytterhoeven
This is no longer done from iop_init() Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k/sun3: Dynamically allocate the table to track IOMMU useGeert Uytterhoeven
As Sun 3 kernels cannot be multi-platform due to the different Sun 3 MMU type, it made sense to statically allocate the table to track IOMMU use. However, Sun 3x kernels can be multi-platform. Furthermore, Sun 3x uses a larger table than Sun 3 (8192 bytes instead of 512 bytes). Hence switch to dynamic allocation of this table using the bootmem allocator to avoid wasting 8192 bytes when not running on a Sun 3x. As this allocator returns zeroed memory, there's no need to explicitly initialize the table to zeroes. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-26m68k: Mark functions only called from setup_arch() __initGeert Uytterhoeven
Some functions that are only called (indirectly) from setup_arch() lack __init annotations. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-11-19Merge branch 'irq-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq cleanups from Ingo Molnar: "This is a multi-arch cleanup series from Thomas Gleixner, which we kept to near the end of the merge window, to not interfere with architecture updates. This series (motivated by the -rt kernel) unifies more aspects of IRQ handling and generalizes PREEMPT_ACTIVE" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: preempt: Make PREEMPT_ACTIVE generic sparc: Use preempt_schedule_irq ia64: Use preempt_schedule_irq m32r: Use preempt_schedule_irq hardirq: Make hardirq bits generic m68k: Simplify low level interrupt handling code genirq: Prevent spurious detection for unconditionally polled interrupts
2013-11-15Merge tag 'for-linus' of git://linux-c6x.org/git/projects/linux-c6x-upstreamingLinus Torvalds
Pull Kconfig cleanups from Mark Salter: "Remove some unused config options from C6X and clean up PC_PARPORT dependencies. The latter was discussed here: https://lkml.org/lkml/2013/10/8/12" * tag 'for-linus' of git://linux-c6x.org/git/projects/linux-c6x-upstreaming: c6x: remove unused COMMON_CLKDEV Kconfig parameter Kconfig cleanup (PARPORT_PC dependencies) x86: select ARCH_MIGHT_HAVE_PC_PARPORT unicore32: select ARCH_MIGHT_HAVE_PC_PARPORT sparc: select ARCH_MIGHT_HAVE_PC_PARPORT sh: select ARCH_MIGHT_HAVE_PC_PARPORT powerpc: select ARCH_MIGHT_HAVE_PC_PARPORT parisc: select ARCH_MIGHT_HAVE_PC_PARPORT mips: select ARCH_MIGHT_HAVE_PC_PARPORT microblaze: select ARCH_MIGHT_HAVE_PC_PARPORT m68k: select ARCH_MIGHT_HAVE_PC_PARPORT ia64: select ARCH_MIGHT_HAVE_PC_PARPORT arm: select ARCH_MIGHT_HAVE_PC_PARPORT alpha: select ARCH_MIGHT_HAVE_PC_PARPORT c6x: remove unused parameter in Kconfig
2013-11-15m68k: handle pgtable_page_ctor() failKirill A. Shutemov
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13preempt: Make PREEMPT_ACTIVE genericThomas Gleixner
No point in having this bit defined by architecture. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20130917183629.090698799@linutronix.de
2013-11-13hardirq: Make hardirq bits genericThomas Gleixner
There is no reason for per arch hardirq bits. Make them all generic Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20130917183628.534494408@linutronix.de
2013-11-13m68k: Simplify low level interrupt handling codeThomas Gleixner
The low level interrupt entry code of m68k contains the following: add_preempt_count(HARDIRQ_OFFSET); do_IRQ(); irq_enter(); add_preempt_count(HARDIRQ_OFFSET); handle_interrupt(); irq_exit(); sub_preempt_count(HARDIRQ_OFFSET); if (in_interrupt()) return; <---- On m68k always taken! if (local_softirq_pending()) do_softirq(); sub_preempt_count(HARDIRQ_OFFSET); if (in_hardirq()) return; if (status_on_stack_has_interrupt_priority_mask > 0) return; if (local_softirq_pending()) do_softirq(); ret_from_exception: if (interrupted_context_is_kernel) return: .... I tried to find a proper explanation for this, but the changelog is sparse and there are no mails explaining it further. But obviously this relates to the interrupt priority levels of the m68k and tries to be extra clever with nested interrupts. Though this cleverness just adds code bloat to the interrupt hotpath. For the common case of non nested interrupts the code runs through two extra conditionals to the only important one, which checks whether the return is to kernel or user space. For the nested case the checks for in_hardirq() and the priority mask value on stack catch only the case where the nested interrupt happens inside the hard irq context of the first interrupt. If the nested interrupt happens while the first interrupt handles soft interrupts, then these extra checks buy nothing. The nested interrupt will fall through to the final kernel/user space return check at ret_from_exception. Changing the code flow in the following way: do_IRQ(); irq_enter(); add_preempt_count(HARDIRQ_OFFSET); handle_interrupt(); irq_exit(); sub_preempt_count(HARDIRQ_OFFSET); if (in_interrupt()) return; if (local_softirq_pending()) do_softirq(); ret_from_exception: if (interrupted_context_is_kernel) return: makes the region protected by the hardirq count slightly smaller and the softirq handling is invoked with a minimal deeper stack. But otherwise it's completely functional equivalent and saves 104 bytes of text in arch/m68k/kernel/entry.o. This modification allows us further to get rid of the limitations which m68k puts on the preempt_count layout, so we can make the preempt count bits completely generic. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Michael Schmitz <schmitz@biophys.uni-duesseldorf.de> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Linux/m68k <linux-m68k@vger.kernel.org> Cc: Andreas Schwab <schwab@linux-m68k.org> Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1311112052360.30673@ionos.tec.linutronix.de
2013-11-12Merge branch 'sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler changes from Ingo Molnar: "The main changes in this cycle are: - (much) improved CONFIG_NUMA_BALANCING support from Mel Gorman, Rik van Riel, Peter Zijlstra et al. Yay! - optimize preemption counter handling: merge the NEED_RESCHED flag into the preempt_count variable, by Peter Zijlstra. - wait.h fixes and code reorganization from Peter Zijlstra - cfs_bandwidth fixes from Ben Segall - SMP load-balancer cleanups from Peter Zijstra - idle balancer improvements from Jason Low - other fixes and cleanups" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (129 commits) ftrace, sched: Add TRACE_FLAG_PREEMPT_RESCHED stop_machine: Fix race between stop_two_cpus() and stop_cpus() sched: Remove unnecessary iteration over sched domains to update nr_busy_cpus sched: Fix asymmetric scheduling for POWER7 sched: Move completion code from core.c to completion.c sched: Move wait code from core.c to wait.c sched: Move wait.c into kernel/sched/ sched/wait: Fix __wait_event_interruptible_lock_irq_timeout() sched: Avoid throttle_cfs_rq() racing with period_timer stopping sched: Guarantee new group-entities always have weight sched: Fix hrtimer_cancel()/rq->lock deadlock sched: Fix cfs_bandwidth misuse of hrtimer_expires_remaining sched: Fix race on toggling cfs_bandwidth_used sched: Remove extra put_online_cpus() inside sched_setaffinity() sched/rt: Fix task_tick_rt() comment sched/wait: Fix build breakage sched/wait: Introduce prepare_to_wait_event() sched/wait: Add ___wait_cond_timeout() to wait_event*_timeout() too sched: Remove get_online_cpus() usage sched: Fix race in migrate_swap_stop() ...