kernel.git/arch/parisc/kernel/irq.c, branch linux-3.13.y

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

2013-11-12T01:02:59Z

Pull IRQ changes from Ingo Molnar: "The biggest change this cycle are the softirq/hardirq stack interaction and nesting fixes, cleanups and reorganizations from Frederic. This is the longer followup story to the softirq nesting fix that is already upstream (commit ded797547548: "irq: Force hardirq exit's softirq processing on its own stack")" * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqchip: bcm2835: Convert to use IRQCHIP_DECLARE macro powerpc: Tell about irq stack coverage x86: Tell about irq stack coverage irq: Optimize softirq stack selection in irq exit irq: Justify the various softirq stack choices irq: Improve a bit softirq debugging irq: Optimize call to softirq on hardirq exit irq: Consolidate do_softirq() arch overriden implementations x86/irq: Correct comment about i8259 initialization

parisc: do not count IPI calls twice

2013-11-07T21:28:54Z

The number of IPI calls is already visible as per-cpu IPI irq counters in/proc/cpuinfo, so let's drop this additional counting. This partly reverts: cd85d55 parisc: more irq statistics in /proc/interrupts Signed-off-by: Helge Deller

irq: Consolidate do_softirq() arch overriden implementations

2013-10-01T10:53:25Z

All arch overriden implementations of do_softirq() share the following common code: disable irqs (to avoid races with the pending check), check if there are softirqs pending, then execute __do_softirq() on a specific stack. Consolidate the common parts such that archs only worry about the stack switch. Acked-by: Linus Torvalds Signed-off-by: Frederic Weisbecker Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Ingo Molnar Cc: Thomas Gleixner Cc: Peter Zijlstra Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Paul Mackerras Cc: James Hogan Cc: James E.J. Bottomley Cc: Helge Deller Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: David S. Miller Cc: Andrew Morton

parisc: fix irq stack on UP and SMP

2013-05-24T21:29:01Z

The logic to detect if the irq stack was already in use with raw_spin_trylock() is wrong, because it will generate a "trylock failure on UP" error message with CONFIG_SMP=n and CONFIG_DEBUG_SPINLOCK=y. arch_spin_trylock() can't be used either since in the CONFIG_SMP=n case no atomic protection is given and we are reentrant here. A mutex didn't worked either and brings more overhead by turning off interrupts. So, let's use the fastest path for parisc which is the ldcw instruction. Counting how often the irq stack was used is pretty useless, so just drop this piece of code. Signed-off-by: Helge Deller

parisc: show number of FPE and unaligned access handler calls in /proc/interrupts

2013-05-24T20:35:26Z

Show number of floating point assistant and unaligned access fixup handler in /proc/interrupts file. Signed-off-by: Helge Deller

parisc: implement irq stacks - part 2 (v2)

2013-05-11T19:10:15Z

This patch fixes few build issues which were introduced with the last irq stack patch, e.g. the combination of stack overflow check and irq stack. Furthermore we now do proper locking and change the irq bh handler to use the irq stack as well. In /proc/interrupts one now can monitor how huge the irq stack has grown and how often it was preferred over the kernel stack. IRQ stacks are now enabled by default just to make sure that we not overflow the kernel stack by accident. Signed-off-by: Helge Deller

parisc: tlb flush counting fix for SMP and UP

2013-05-07T21:44:04Z

Fix up build error on UP and show correctly number of function call (ipi) irqs. Signed-off-by: Helge Deller

parisc: more irq statistics in /proc/interrupts

2013-05-07T20:39:22Z

Add framework and initial values for more fine grained statistics in /proc/interrupts. Signed-off-by: Helge Deller

parisc: implement irq stacks

2013-05-07T20:30:35Z

Default kernel stack size on parisc is 16k. During tests we found that the kernel stack can easily grow beyond 13k, which leaves 3k left for irq processing. This patch adds the possibility to activate an additional stack of 16k per CPU which is being used during irq processing. This implementation does not yet uses this irq stack for the irq bh handler. The assembler code for call_on_stack was heavily cleaned up by John David Anglin. CC: John David Anglin Signed-off-by: Helge Deller

parisc: add kernel stack overflow check

2013-05-07T19:34:07Z

Add the CONFIG_DEBUG_STACKOVERFLOW config option to enable checks to detect kernel stack overflows. Stack overflows can not be detected reliable since we do not want to introduce too much overhead. Instead, during irq processing in do_cpu_irq_mask() we check kernel stack usage of the interrupted kernel process. Kernel threads can be easily detected by checking the value of space register 7 (sr7) which is zero when running inside the kernel. Since THREAD_SIZE is 16k and PAGE_SIZE is 4k, reduce the alignment of the init thread to the lower value (PAGE_SIZE) in the kernel vmlinux.ld.S linker script. Signed-off-by: Helge Deller