Re: [PATCH 1/6] powerpc: Move #ifdef'ed body of do_IRQ() into a separate function
On Tue, Apr 28, 2009 at 10:49:07AM +1000, Michael Ellerman wrote: On Sat, 2009-04-25 at 20:18 +0200, Christoph Hellwig wrote: On Thu, Apr 23, 2009 at 11:31:37AM +1000, Michael Ellerman wrote: +#ifdef CONFIG_IRQSTACKS Wasn't there a plan to make CONFIG_IRQSTACKS the unconditional default? Not sure. Looks like the 64-bit configs all turn it on, and all but one or two of the 32-bit configs don't. Yeah, but do they have a reason not to turn it on? Having irqstacks is a lot safer than no having it because the stack useage is a lot more predictable. And not having to maintain two codepathes is also a benefit all by itself. ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
Re: [PATCH 1/6] powerpc: Move #ifdef'ed body of do_IRQ() into a separate function
On Apr 29, 2009, at 6:44 AM, Christoph Hellwig wrote: On Tue, Apr 28, 2009 at 10:49:07AM +1000, Michael Ellerman wrote: On Sat, 2009-04-25 at 20:18 +0200, Christoph Hellwig wrote: On Thu, Apr 23, 2009 at 11:31:37AM +1000, Michael Ellerman wrote: +#ifdef CONFIG_IRQSTACKS Wasn't there a plan to make CONFIG_IRQSTACKS the unconditional default? Not sure. Looks like the 64-bit configs all turn it on, and all but one or two of the 32-bit configs don't. Yeah, but do they have a reason not to turn it on? Having irqstacks is a lot safer than no having it because the stack useage is a lot more predictable. And not having to maintain two codepathes is also a benefit all by itself. I think Ben, Paul and I had discussed just universally enabling it. Can't remember why Ben hadn't done that yet. - k ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
Re: [PATCH 1/6] powerpc: Move #ifdef'ed body of do_IRQ() into a separate function
On Wed, 2009-04-29 at 07:48 -0500, Kumar Gala wrote: I think Ben, Paul and I had discussed just universally enabling it. Can't remember why Ben hadn't done that yet. Slipped between the cracks. Patch welcome. Cheers, Ben. ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
[PATCH 1/6] powerpc: Move #ifdef'ed body of do_IRQ() into a separate function
Rather than a giant ifdef in the body of do_IRQ(), including a
dangling else, move the irq stack logic into a separate routine and
do the ifdef there.
Signed-off-by: Michael Ellerman mich...@ellerman.id.au
---
arch/powerpc/kernel/irq.c | 96 ++---
1 files changed, 56 insertions(+), 40 deletions(-)
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
index 8c1a496..3d3658d 100644
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c
@@ -248,13 +248,63 @@ void fixup_irqs(cpumask_t map)
}
#endif
+#ifdef CONFIG_IRQSTACKS
+static inline void handle_one_irq(unsigned int irq)
+{
+ struct thread_info *curtp, *irqtp;
+ unsigned long saved_sp_limit;
+ struct irq_desc *desc;
+ void *handler;
+
+ /* Switch to the irq stack to handle this */
+ curtp = current_thread_info();
+ irqtp = hardirq_ctx[smp_processor_id()];
+
+ if (curtp == irqtp) {
+ /* We're already on the irq stack, just handle it */
+ generic_handle_irq(irq);
+ return;
+ }
+
+ desc = irq_desc + irq;
+ saved_sp_limit = current-thread.ksp_limit;
+
+ handler = desc-handle_irq;
+ if (handler == NULL)
+ handler = __do_IRQ;
+
+ irqtp-task = curtp-task;
+ irqtp-flags = 0;
+
+ /* Copy the softirq bits in preempt_count so that the
+* softirq checks work in the hardirq context. */
+ irqtp-preempt_count = (irqtp-preempt_count ~SOFTIRQ_MASK) |
+ (curtp-preempt_count SOFTIRQ_MASK);
+
+ current-thread.ksp_limit = (unsigned long)irqtp +
+ _ALIGN_UP(sizeof(struct thread_info), 16);
+
+ call_handle_irq(irq, desc, irqtp, handler);
+ current-thread.ksp_limit = saved_sp_limit;
+ irqtp-task = NULL;
+
+ /* Set any flag that may have been set on the
+* alternate stack
+*/
+ if (irqtp-flags)
+ set_bits(irqtp-flags, curtp-flags);
+}
+#else
+static inline void handle_one_irq(unsigned int irq)
+{
+ generic_handle_irq(irq);
+}
+#endif
+
void do_IRQ(struct pt_regs *regs)
{
struct pt_regs *old_regs = set_irq_regs(regs);
unsigned int irq;
-#ifdef CONFIG_IRQSTACKS
- struct thread_info *curtp, *irqtp;
-#endif
irq_enter();
@@ -282,43 +332,9 @@ void do_IRQ(struct pt_regs *regs)
*/
irq = ppc_md.get_irq();
- if (irq != NO_IRQ irq != NO_IRQ_IGNORE) {
-#ifdef CONFIG_IRQSTACKS
- /* Switch to the irq stack to handle this */
- curtp = current_thread_info();
- irqtp = hardirq_ctx[smp_processor_id()];
- if (curtp != irqtp) {
- struct irq_desc *desc = irq_desc + irq;
- void *handler = desc-handle_irq;
- unsigned long saved_sp_limit =
current-thread.ksp_limit;
- if (handler == NULL)
- handler = __do_IRQ;
- irqtp-task = curtp-task;
- irqtp-flags = 0;
-
- /* Copy the softirq bits in preempt_count so that the
-* softirq checks work in the hardirq context.
-*/
- irqtp-preempt_count =
- (irqtp-preempt_count ~SOFTIRQ_MASK) |
- (curtp-preempt_count SOFTIRQ_MASK);
-
- current-thread.ksp_limit = (unsigned long)irqtp +
- _ALIGN_UP(sizeof(struct thread_info), 16);
- call_handle_irq(irq, desc, irqtp, handler);
- current-thread.ksp_limit = saved_sp_limit;
- irqtp-task = NULL;
-
-
- /* Set any flag that may have been set on the
-* alternate stack
-*/
- if (irqtp-flags)
- set_bits(irqtp-flags, curtp-flags);
- } else
-#endif
- generic_handle_irq(irq);
- } else if (irq != NO_IRQ_IGNORE)
+ if (irq != NO_IRQ irq != NO_IRQ_IGNORE)
+ handle_one_irq(irq);
+ else if (irq != NO_IRQ_IGNORE)
/* That's not SMP safe ... but who cares ? */
ppc_spurious_interrupts++;
--
1.6.2.1
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Re: [PATCH 1/6] powerpc: Move #ifdef'ed body of do_IRQ() into a separate function
On Sat, 2009-04-25 at 20:18 +0200, Christoph Hellwig wrote: On Thu, Apr 23, 2009 at 11:31:37AM +1000, Michael Ellerman wrote: +#ifdef CONFIG_IRQSTACKS Wasn't there a plan to make CONFIG_IRQSTACKS the unconditional default? Not sure. Looks like the 64-bit configs all turn it on, and all but one or two of the 32-bit configs don't. cheers signature.asc Description: This is a digitally signed message part ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
Re: [PATCH 1/6] powerpc: Move #ifdef'ed body of do_IRQ() into a separate function
On Thu, Apr 23, 2009 at 11:31:37AM +1000, Michael Ellerman wrote: +#ifdef CONFIG_IRQSTACKS Wasn't there a plan to make CONFIG_IRQSTACKS the unconditional default? The actual patch looks good to me. ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
Re: [PATCH 1/6] powerpc: Move #ifdef'ed body of do_IRQ() into a separate function
On Thu, Apr 23, 2009 at 11:31:37AM +1000, Michael Ellerman wrote: + handler = desc-handler; Should be desc-handle_irq. It's fixed in a later patch, but this breaks bisect. -Scott ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
Re: [PATCH 1/6] powerpc: Move #ifdef'ed body of do_IRQ() into a separate function
On Thu, 2009-04-23 at 11:49 -0500, Scott Wood wrote: On Thu, Apr 23, 2009 at 11:31:37AM +1000, Michael Ellerman wrote: + handler = desc-handler; Should be desc-handle_irq. It's fixed in a later patch, but this breaks bisect. Ah crud, thanks for spotting it. That's an artifact of me reordering the patches. Will resend. cheers signature.asc Description: This is a digitally signed message part ___ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
