From 945feb174b14e7098cc7ecf0cf4768d35bc52f9c Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Thu, 17 Apr 2008 14:35:01 +1000 Subject: [POWERPC] irqtrace support for 64-bit powerpc This adds the low level irq tracing hooks to the powerpc architecture needed to enable full lockdep functionality. This is partly based on Johannes Berg's initial version. I removed the asm trampoline that isn't needed (thus improving performance) and modified all sorts of bits and pieces, reworking most of the assembly, etc... Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Paul Mackerras --- arch/powerpc/kernel/head_64.S | 47 +++++++++++++++++++++++++++++-------------- 1 file changed, 32 insertions(+), 15 deletions(-) (limited to 'arch/powerpc/kernel/head_64.S') diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S index 44229c3749a..215973a2c8d 100644 --- a/arch/powerpc/kernel/head_64.S +++ b/arch/powerpc/kernel/head_64.S @@ -36,8 +36,7 @@ #include #include #include - -#define DO_SOFT_DISABLE +#include /* * We layout physical memory as follows: @@ -450,8 +449,8 @@ bad_stack: */ fast_exc_return_irq: /* restores irq state too */ ld r3,SOFTE(r1) + TRACE_AND_RESTORE_IRQ(r3); ld r12,_MSR(r1) - stb r3,PACASOFTIRQEN(r13) /* restore paca->soft_enabled */ rldicl r4,r12,49,63 /* get MSR_EE to LSB */ stb r4,PACAHARDIRQEN(r13) /* restore paca->hard_enabled */ b 1f @@ -824,7 +823,7 @@ _STATIC(load_up_altivec) * Hash table stuff */ .align 7 -_GLOBAL(do_hash_page) +_STATIC(do_hash_page) std r3,_DAR(r1) std r4,_DSISR(r1) @@ -835,6 +834,27 @@ BEGIN_FTR_SECTION bne- do_ste_alloc /* If so handle it */ END_FTR_SECTION_IFCLR(CPU_FTR_SLB) + /* + * On iSeries, we soft-disable interrupts here, then + * hard-enable interrupts so that the hash_page code can spin on + * the hash_table_lock without problems on a shared processor. + */ + DISABLE_INTS + + /* + * Currently, trace_hardirqs_off() will be called by DISABLE_INTS + * and will clobber volatile registers when irq tracing is enabled + * so we need to reload them. It may be possible to be smarter here + * and move the irq tracing elsewhere but let's keep it simple for + * now + */ +#ifdef CONFIG_TRACE_IRQFLAGS + ld r3,_DAR(r1) + ld r4,_DSISR(r1) + ld r5,_TRAP(r1) + ld r12,_MSR(r1) + clrrdi r5,r5,4 +#endif /* CONFIG_TRACE_IRQFLAGS */ /* * We need to set the _PAGE_USER bit if MSR_PR is set or if we are * accessing a userspace segment (even from the kernel). We assume @@ -847,13 +867,6 @@ END_FTR_SECTION_IFCLR(CPU_FTR_SLB) ori r4,r4,1 /* add _PAGE_PRESENT */ rlwimi r4,r5,22+2,31-2,31-2 /* Set _PAGE_EXEC if trap is 0x400 */ - /* - * On iSeries, we soft-disable interrupts here, then - * hard-enable interrupts so that the hash_page code can spin on - * the hash_table_lock without problems on a shared processor. - */ - DISABLE_INTS - /* * r3 contains the faulting address * r4 contains the required access permissions @@ -864,7 +877,6 @@ END_FTR_SECTION_IFCLR(CPU_FTR_SLB) bl .hash_page /* build HPTE if possible */ cmpdi r3,0 /* see if hash_page succeeded */ -#ifdef DO_SOFT_DISABLE BEGIN_FW_FTR_SECTION /* * If we had interrupts soft-enabled at the point where the @@ -876,7 +888,7 @@ BEGIN_FW_FTR_SECTION */ beq 13f END_FW_FTR_SECTION_IFSET(FW_FEATURE_ISERIES) -#endif + BEGIN_FW_FTR_SECTION /* * Here we have interrupts hard-disabled, so it is sufficient @@ -890,11 +902,12 @@ END_FW_FTR_SECTION_IFCLR(FW_FEATURE_ISERIES) /* * hash_page couldn't handle it, set soft interrupt enable back - * to what it was before the trap. Note that .local_irq_restore + * to what it was before the trap. Note that .raw_local_irq_restore * handles any interrupts pending at this point. */ ld r3,SOFTE(r1) - bl .local_irq_restore + TRACE_AND_RESTORE_IRQ_PARTIAL(r3, 11f) + bl .raw_local_irq_restore b 11f /* Here we have a page fault that hash_page can't handle. */ @@ -1493,6 +1506,10 @@ _INIT_STATIC(start_here_multiplatform) addi r2,r2,0x4000 add r2,r2,r26 + /* Set initial ptr to current */ + LOAD_REG_IMMEDIATE(r4, init_task) + std r4,PACACURRENT(r13) + /* Do very early kernel initializations, including initial hash table, * stab and slb setup before we turn on relocation. */ -- cgit v1.2.3