From 5d38902c483881645ba16058cffaa478b81e5cfa Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Wed, 17 Jun 2009 17:43:59 +0000 Subject: powerpc: Add irqtrace support for 32-bit powerpc Based on initial work from: Dale Farnsworth Add the low level irq tracing hooks for 32-bit powerpc needed to enable full lockdep functionality. The approach taken to deal with the code in entry_32.S is that we don't trace all the transitions of MSR:EE when we just turn it off to peek at TI_FLAGS without races. Only when we are calling into C code or returning from exceptions with a state that have changed from what lockdep thinks. There's a little bugger though: If we take an exception that keeps interrupts enabled (such as an alignment exception) while interrupts are enabled, we will call trace_hardirqs_on() on the way back spurriously. Not a big deal, but to get rid of it would require remembering in pt_regs that the exception was one of the type that kept interrupts enabled which we don't know at this stage. (Well, we could test all cases for regs->trap but that sucks too much). Signed-off-by: Benjamin Herrenschmidt Tested-by: Kumar Gala --- arch/powerpc/kernel/setup_32.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/powerpc/kernel/setup_32.c') diff --git a/arch/powerpc/kernel/setup_32.c b/arch/powerpc/kernel/setup_32.c index 1d154248cf40..e1e3059cf34b 100644 --- a/arch/powerpc/kernel/setup_32.c +++ b/arch/powerpc/kernel/setup_32.c @@ -119,6 +119,8 @@ notrace unsigned long __init early_init(unsigned long dt_ptr) */ notrace void __init machine_init(unsigned long dt_ptr) { + lockdep_init(); + /* Enable early debugging if any specified (see udbg.h) */ udbg_early_init(); -- cgit v1.2.1