kernel.git/arch/s390/kernel/smp.c, branch linux-3.11.y

s390: delete __cpuinit usage from all s390 files

2013-07-14T23:36:53Z

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/s390 uses of the __cpuinit macros from all C files. Currently s390 does not have any __CPUINIT used in assembly files. [1] https://lkml.org/lkml/2013/5/20/589 Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: linux390@de.ibm.com Cc: linux-s390@vger.kernel.org Signed-off-by: Paul Gortmaker

s390/smp: get rid of generic_smp_call_function_interrupt

2013-06-26T19:10:01Z

Since 9a46ad6d6 "smp: make smp_call_function_many() use logic similar to smp_call_function_single()" generic_smp_call_function_interrupt() is only an alias to generic_smp_call_function_single_interrupt(). So remove the superfluous variant. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390/smp: lost IPIs on cpu hotplug

2013-05-27T07:16:15Z

IPIs might be lost when a cpu gets brought offline: When stop_machine executes its state machine there is a race window for the state STOPMACHINE_DISABLE_IRQ where the to be brought offline cpu might already have irqs disabled but a different cpu still may have irqs enabled. If the enabled cpu receives an interrupt and as a result sends an IPI to the to be offlined cpu in its bottom halve context, the IPI won't be noticed before the cpu is offline. In fact the race window is much larger since there is no guarantee when an IPI will be received. To fix this check for enqueued but not yet received IPIs in the cpu_disable() path and call the respective handlers before the cpu is marked offline. Reported-by: Juergen Doelle Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390/smp: fix cpu re-scan vs. cpu state

2013-05-17T09:47:01Z

The cpu-info array starts with a list of cpus in configured state, followed by the cpus in standby state. The comparison to decide which state a cpu has is incorrect, this causes configured cpus appear as standby cpus. The correct comparison is the index of the new cpu in the cpu-info array vs. the number of configured cpus. Signed-off-by: Martin Schwidefsky

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

2013-04-30T14:50:17Z

Pull SMP/hotplug changes from Ingo Molnar: "This is a pretty large, multi-arch series unifying and generalizing the various disjunct pieces of idle routines that architectures have historically copied from each other and have grown in random, wildly inconsistent and sometimes buggy directions: 101 files changed, 455 insertions(+), 1328 deletions(-) this went through a number of review and test iterations before it was committed, it was tested on various architectures, was exposed to linux-next for quite some time - nevertheless it might cause problems on architectures that don't read the mailing lists and don't regularly test linux-next. This cat herding excercise was motivated by the -rt kernel, and was brought to you by Thomas "the Whip" Gleixner." * 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits) idle: Remove GENERIC_IDLE_LOOP config switch um: Use generic idle loop ia64: Make sure interrupts enabled when we "safe_halt()" sparc: Use generic idle loop idle: Remove unused ARCH_HAS_DEFAULT_IDLE bfin: Fix typo in arch_cpu_idle() xtensa: Use generic idle loop x86: Use generic idle loop unicore: Use generic idle loop tile: Use generic idle loop tile: Enter idle with preemption disabled sh: Use generic idle loop score: Use generic idle loop s390: Use generic idle loop powerpc: Use generic idle loop parisc: Use generic idle loop openrisc: Use generic idle loop mn10300: Use generic idle loop mips: Use generic idle loop microblaze: Use generic idle loop ...

s390: lowcore stack pointer offsets

2013-04-26T07:07:01Z

Store the stack pointers in the lowcore for the kernel stack, the async stack and the panic stack with the offset required for the first user. This avoids an unnecessary add instruction on the system call path. Signed-off-by: Martin Schwidefsky

s390: Use generic idle loop

2013-04-08T15:39:27Z

Signed-off-by: Thomas Gleixner Cc: Linus Torvalds Cc: Rusty Russell Cc: Paul McKenney Cc: Peter Zijlstra Reviewed-by: Cc: Srivatsa S. Bhat Cc: Magnus Damm Acked-by: Heiko Carstens Link: http://lkml.kernel.org/r/20130321215235.090816526@linutronix.de Signed-off-by: Thomas Gleixner

s390/time: rename tod clock access functions

2013-02-14T14:55:10Z

Fix name clash with some common code device drivers and add "tod" to all tod clock access function names. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390/irq: count cpu restart events

2013-01-08T09:57:07Z

Count CPU Restart events and make them visible via /proc/interrupts. Every CPU hotplug (online) event will increase the per cpu counter. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky

s390/irq: remove split irq fields from /proc/stat

2013-01-08T09:57:07Z

Now that irq sum accounting for /proc/stat's "intr" line works again we have the oddity that the sum field (first field) contains only the sum of the second (external irqs) and third field (I/O interrupts). The reason for that is that these two fields are already sums of all other fields. So if we would sum up everything we would count every interrupt twice. This is broken since the split interrupt accounting was merged two years ago: 052ff461c8427629aee887ccc27478fc7373237c "[S390] irq: have detailed statistics for interrupt types". To fix this remove the split interrupt fields from /proc/stat's "intr" line again and only have them in /proc/interrupts. This restores the old behaviour, seems to be the only sane fix and mimics a behaviour from other architectures where /proc/interrupts also contains more than /proc/stat's "intr" line does. Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky