[SPARC64]: Add irqtrace/stacktrace/lockdep support.

Signed-off-by: David S. Miller <davem@davemloft.net>

9 files changed, 129 insertions, 11 deletions

diff --git a/arch/sparc64/Kconfig b/arch/sparc64/Kconfig
index d391d11f245a..d41f66ac7fff 100644
--- a/arch/sparc64/Kconfig
+++ b/arch/sparc64/Kconfig
@@ -26,6 +26,14 @@ config MMU
         bool
         default y
 
+config STACKTRACE_SUPPORT
+        bool
+        default y
+
+config LOCKDEP_SUPPORT
+        bool
+        default y
+
 config TIME_INTERPOLATION
         bool
         default y
diff --git a/arch/sparc64/Kconfig.debug b/arch/sparc64/Kconfig.debug
index afe0a7720a26..1f130f3b6c24 100644
--- a/arch/sparc64/Kconfig.debug
+++ b/arch/sparc64/Kconfig.debug
@@ -1,5 +1,9 @@
 menu "Kernel hacking"
 
+config TRACE_IRQFLAGS_SUPPORT
+        bool
+        default y
+
 source "lib/Kconfig.debug"
 
 config DEBUG_STACK_USAGE
diff --git a/arch/sparc64/kernel/Makefile b/arch/sparc64/kernel/Makefile
index e1eabebaed39..eff0c01d3579 100644
--- a/arch/sparc64/kernel/Makefile
+++ b/arch/sparc64/kernel/Makefile
@@ -14,6 +14,7 @@ obj-y		:= process.o setup.o cpu.o idprom.o \
                    power.o sbus.o iommu_common.o sparc64_ksyms.o chmc.o \
                    visemul.o prom.o of_device.o
 
+obj-$(CONFIG_STACKTRACE) += stacktrace.o
 obj-$(CONFIG_PCI)        += ebus.o isa.o pci_common.o pci_iommu.o \
                             pci_psycho.o pci_sabre.o pci_schizo.o \
                             pci_sun4v.o pci_sun4v_asm.o
diff --git a/arch/sparc64/kernel/entry.S b/arch/sparc64/kernel/entry.S
index 6f28bec0a9bf..c15a3edcb826 100644
--- a/arch/sparc64/kernel/entry.S
+++ b/arch/sparc64/kernel/entry.S
@@ -597,7 +597,12 @@ __spitfire_cee_trap_continue:
 1:      ba,pt           %xcc, etrap_irq
          rd             %pc, %g7
 
-2:      mov             %l4, %o1
+2:
+#ifdef CONFIG_TRACE_IRQFLAGS
+        call    trace_hardirqs_off
+         nop
+#endif
+        mov             %l4, %o1
         mov             %l5, %o2
         call            spitfire_access_error
          add            %sp, PTREGS_OFF, %o0
@@ -824,6 +829,10 @@ do_cheetah_plus_data_parity:
         wrpr            %g0, 15, %pil
         ba,pt           %xcc, etrap_irq
          rd             %pc, %g7
+#ifdef CONFIG_TRACE_IRQFLAGS
+        call            trace_hardirqs_off
+         nop
+#endif
         mov             0x0, %o0
         call            cheetah_plus_parity_error
          add            %sp, PTREGS_OFF, %o1
@@ -855,6 +864,10 @@ do_cheetah_plus_insn_parity:
         wrpr            %g0, 15, %pil
         ba,pt           %xcc, etrap_irq
          rd             %pc, %g7
+#ifdef CONFIG_TRACE_IRQFLAGS
+        call            trace_hardirqs_off
+         nop
+#endif
         mov             0x1, %o0
         call            cheetah_plus_parity_error
          add            %sp, PTREGS_OFF, %o1
@@ -1183,6 +1196,10 @@ c_fast_ecc:
         wrpr            %g0, 15, %pil
         ba,pt           %xcc, etrap_irq
          rd             %pc, %g7
+#ifdef CONFIG_TRACE_IRQFLAGS
+        call            trace_hardirqs_off
+         nop
+#endif
         mov             %l4, %o1
         mov             %l5, %o2
         call            cheetah_fecc_handler
@@ -1211,6 +1228,10 @@ c_cee:
         wrpr            %g0, 15, %pil
         ba,pt           %xcc, etrap_irq
          rd             %pc, %g7
+#ifdef CONFIG_TRACE_IRQFLAGS
+        call            trace_hardirqs_off
+         nop
+#endif
         mov             %l4, %o1
         mov             %l5, %o2
         call            cheetah_cee_handler
@@ -1239,6 +1260,10 @@ c_deferred:
         wrpr            %g0, 15, %pil
         ba,pt           %xcc, etrap_irq
          rd             %pc, %g7
+#ifdef CONFIG_TRACE_IRQFLAGS
+        call            trace_hardirqs_off
+         nop
+#endif
         mov             %l4, %o1
         mov             %l5, %o2
         call            cheetah_deferred_handler
diff --git a/arch/sparc64/kernel/head.S b/arch/sparc64/kernel/head.S
index c8e9dc9d68a9..03ffaf895a22 100644
--- a/arch/sparc64/kernel/head.S
+++ b/arch/sparc64/kernel/head.S
@@ -489,6 +489,14 @@ tlb_fixup_done:
         call    __bzero
          sub    %o1, %o0, %o1
 
+#ifdef CONFIG_LOCKDEP
+        /* We have this call this super early, as even prom_init can grab
+         * spinlocks and thus call into the lockdep code.
+         */
+        call    lockdep_init
+         nop
+#endif
+
         mov     %l6, %o1                        ! OpenPROM stack
         call    prom_init
          mov    %l7, %o0                        ! OpenPROM cif handler
diff --git a/arch/sparc64/kernel/rtrap.S b/arch/sparc64/kernel/rtrap.S
index 3522cd66f3bb..079d18a11d24 100644
--- a/arch/sparc64/kernel/rtrap.S
+++ b/arch/sparc64/kernel/rtrap.S
@@ -165,14 +165,26 @@ rtrap:
 __handle_softirq_continue:
 rtrap_xcall:
                 sethi                   %hi(0xf << 20), %l4
-                andcc                   %l1, TSTATE_PRIV, %l3
                 and                     %l1, %l4, %l4
+                andn                    %l1, %l4, %l1
+                srl                     %l4, 20, %l4
+#ifdef CONFIG_TRACE_IRQFLAGS
+                brnz,pn                 %l4, rtrap_no_irq_enable
+                 nop
+                call                    trace_hardirqs_on
+                 nop
+                wrpr                    %l4, %pil
+rtrap_no_irq_enable:
+#endif
+                andcc                   %l1, TSTATE_PRIV, %l3
                 bne,pn                  %icc, to_kernel
-                 andn                   %l1, %l4, %l1
+                 nop
 
                 /* We must hold IRQs off and atomically test schedule+signal
                  * state, then hold them off all the way back to userspace.
-                 * If we are returning to kernel, none of this matters.
+                 * If we are returning to kernel, none of this matters.  Note
+                 * that we are disabling interrupts via PSTATE_IE, not using
+                 * %pil.
                  *
                  * If we do not do this, there is a window where we would do
                  * the tests, later the signal/resched event arrives but we do
@@ -256,7 +268,6 @@ rt_continue:	ldx			[%sp + PTREGS_OFF + PT_V9_G1], %g1
 
                 ld                      [%sp + PTREGS_OFF + PT_V9_Y], %o3
                 wr                      %o3, %g0, %y
-                srl                     %l4, 20, %l4
                 wrpr                    %l4, 0x0, %pil
                 wrpr                    %g0, 0x1, %tl
                 wrpr                    %l1, %g0, %tstate
@@ -374,8 +385,8 @@ to_kernel:
                  ldx                    [%g6 + TI_FLAGS], %l5
                 andcc                   %l5, _TIF_NEED_RESCHED, %g0
                 be,pt                   %xcc, kern_fpucheck
-                 srl                    %l4, 20, %l5
-                cmp                     %l5, 0
+                 nop
+                cmp                     %l4, 0
                 bne,pn                  %xcc, kern_fpucheck
                  sethi                  %hi(PREEMPT_ACTIVE), %l6
                 stw                     %l6, [%g6 + TI_PRE_COUNT]
diff --git a/arch/sparc64/kernel/stacktrace.c b/arch/sparc64/kernel/stacktrace.c
new file mode 100644
index 000000000000..c4d15f2762b9
--- /dev/null
+++ b/arch/sparc64/kernel/stacktrace.c
@@ -0,0 +1,41 @@
+#include <linux/sched.h>
+#include <linux/stacktrace.h>
+#include <linux/thread_info.h>
+#include <asm/ptrace.h>
+
+void save_stack_trace(struct stack_trace *trace, struct task_struct *task)
+{
+        unsigned long ksp, fp, thread_base;
+        struct thread_info *tp;
+
+        if (!task)
+                task = current;
+        tp = task_thread_info(task);
+        if (task == current) {
+                flushw_all();
+                __asm__ __volatile__(
+                        "mov    %%fp, %0"
+                        : "=r" (ksp)
+                );
+        } else
+                ksp = tp->ksp;
+
+        fp = ksp + STACK_BIAS;
+        thread_base = (unsigned long) tp;
+        do {
+                struct reg_window *rw;
+
+                /* Bogus frame pointer? */
+                if (fp < (thread_base + sizeof(struct thread_info)) ||
+                    fp >= (thread_base + THREAD_SIZE))
+                        break;
+
+                rw = (struct reg_window *) fp;
+                if (trace->skip > 0)
+                        trace->skip--;
+                else
+                        trace->entries[trace->nr_entries++] = rw->ins[7];
+
+                fp = rw->ins[6] + STACK_BIAS;
+        } while (trace->nr_entries < trace->max_entries);
+}
diff --git a/arch/sparc64/kernel/sun4v_ivec.S b/arch/sparc64/kernel/sun4v_ivec.S
index 49703c3c5769..405855dd886b 100644
--- a/arch/sparc64/kernel/sun4v_ivec.S
+++ b/arch/sparc64/kernel/sun4v_ivec.S
@@ -190,7 +190,10 @@ sun4v_res_mondo:
         mov     %g1, %g4
         ba,pt   %xcc, etrap_irq
          rd     %pc, %g7
-
+#ifdef CONFIG_TRACE_IRQFLAGS
+        call            trace_hardirqs_off
+         nop
+#endif
         /* Log the event.  */
         add     %sp, PTREGS_OFF, %o0
         call    sun4v_resum_error
@@ -216,7 +219,10 @@ sun4v_res_mondo_queue_full:
         wrpr    %g0, 15, %pil
         ba,pt   %xcc, etrap_irq
          rd     %pc, %g7
-
+#ifdef CONFIG_TRACE_IRQFLAGS
+        call            trace_hardirqs_off
+         nop
+#endif
         call    sun4v_resum_overflow
          add    %sp, PTREGS_OFF, %o0
 
@@ -295,7 +301,10 @@ sun4v_nonres_mondo:
         mov     %g1, %g4
         ba,pt   %xcc, etrap_irq
          rd     %pc, %g7
-
+#ifdef CONFIG_TRACE_IRQFLAGS
+        call            trace_hardirqs_off
+         nop
+#endif
         /* Log the event.  */
         add     %sp, PTREGS_OFF, %o0
         call    sun4v_nonresum_error
@@ -321,7 +330,10 @@ sun4v_nonres_mondo_queue_full:
         wrpr    %g0, 15, %pil
         ba,pt   %xcc, etrap_irq
          rd     %pc, %g7
-
+#ifdef CONFIG_TRACE_IRQFLAGS
+        call            trace_hardirqs_off
+         nop
+#endif
         call    sun4v_nonresum_overflow
          add    %sp, PTREGS_OFF, %o0
 
diff --git a/arch/sparc64/mm/ultra.S b/arch/sparc64/mm/ultra.S
index d70b60a3bbcc..737c26923c09 100644
--- a/arch/sparc64/mm/ultra.S
+++ b/arch/sparc64/mm/ultra.S
@@ -477,6 +477,10 @@ xcall_sync_tick:
         sethi           %hi(109f), %g7
         b,pt            %xcc, etrap_irq
 109:     or             %g7, %lo(109b), %g7
+#ifdef CONFIG_TRACE_IRQFLAGS
+        call            trace_hardirqs_off
+         nop
+#endif
         call            smp_synchronize_tick_client
          nop
         clr             %l6
@@ -508,6 +512,10 @@ xcall_report_regs:
         sethi           %hi(109f), %g7
         b,pt            %xcc, etrap_irq
 109:     or             %g7, %lo(109b), %g7
+#ifdef CONFIG_TRACE_IRQFLAGS
+        call            trace_hardirqs_off
+         nop
+#endif
         call            __show_regs
          add            %sp, PTREGS_OFF, %o0
         clr             %l6