Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 103 insertions, 0 deletions

diff --git a/arch/alpha/lib/stacktrace.c b/arch/alpha/lib/stacktrace.c
new file mode 100644
index 000000000000..6d432e42aedc
--- /dev/null
+++ b/arch/alpha/lib/stacktrace.c
@@ -0,0 +1,103 @@
+#include <linux/kernel.h>
+#include <asm/system.h>
+
+typedef unsigned int instr;
+
+#define MAJOR_OP        0xfc000000
+#define LDA_OP          0x20000000
+#define STQ_OP          0xb4000000
+#define BR_OP           0xc0000000
+
+#define STK_ALLOC_1     0x23de8000 /* lda $30,-X($30) */
+#define STK_ALLOC_1M    0xffff8000
+#define STK_ALLOC_2     0x43c0153e /* subq $30,X,$30 */
+#define STK_ALLOC_2M    0xffe01fff
+
+#define MEM_REG         0x03e00000
+#define MEM_BASE        0x001f0000
+#define MEM_OFF         0x0000ffff
+#define MEM_OFF_SIGN    0x00008000
+#define BASE_SP         0x001e0000
+
+#define STK_ALLOC_MATCH(INSTR)                  \
+  (((INSTR) & STK_ALLOC_1M) == STK_ALLOC_1      \
+   || ((INSTR) & STK_ALLOC_2M) == STK_ALLOC_2)
+#define STK_PUSH_MATCH(INSTR) \
+  (((INSTR) & (MAJOR_OP | MEM_BASE | MEM_OFF_SIGN)) == (STQ_OP | BASE_SP))
+#define MEM_OP_OFFSET(INSTR) \
+  (((long)((INSTR) & MEM_OFF) << 48) >> 48)
+#define MEM_OP_REG(INSTR) \
+  (((INSTR) & MEM_REG) >> 22)
+
+/* Branches, jumps, PAL calls, and illegal opcodes end a basic block. */
+#define BB_END(INSTR)                                           \
+  (((instr)(INSTR) >= BR_OP) | ((instr)(INSTR) < LDA_OP) |      \
+   ((((instr)(INSTR) ^ 0x60000000) < 0x20000000) &              \
+    (((instr)(INSTR) & 0x0c000000) != 0)))
+
+#define IS_KERNEL_TEXT(PC) ((unsigned long)(PC) > START_ADDR)
+
+static char reg_name[][4] = {
+        "v0 ", "t0 ", "t1 ", "t2 ", "t3 ", "t4 ", "t5 ", "t6 ", "t7 ",
+        "s0 ", "s1 ", "s2 ", "s3 ", "s4 ", "s5 ", "s6 ", "a0 ", "a1 ",
+        "a2 ", "a3 ", "a4 ", "a5 ", "t8 ", "t9 ", "t10", "t11", "ra ",
+        "pv ", "at ", "gp ", "sp ", "0"
+};
+
+
+static instr *
+display_stored_regs(instr * pro_pc, unsigned char * sp)
+{
+        instr * ret_pc = 0;
+        int reg;
+        unsigned long value;
+
+        printk("Prologue [<%p>], Frame %p:\n", pro_pc, sp);
+        while (!BB_END(*pro_pc))
+                if (STK_PUSH_MATCH(*pro_pc)) {
+                        reg = (*pro_pc & MEM_REG) >> 21;
+                        value = *(unsigned long *)(sp + (*pro_pc & MEM_OFF));
+                        if (reg == 26)
+                                ret_pc = (instr *)value;
+                        printk("\t\t%s / 0x%016lx\n", reg_name[reg], value);
+                }
+        return ret_pc;
+}
+
+static instr *
+seek_prologue(instr * pc)
+{
+        while (!STK_ALLOC_MATCH(*pc))
+                --pc;
+        while (!BB_END(*(pc - 1)))
+                --pc;
+        return pc;
+}
+
+static long
+stack_increment(instr * prologue_pc)
+{
+        while (!STK_ALLOC_MATCH(*prologue_pc))
+                ++prologue_pc;
+
+        /* Count the bytes allocated. */
+        if ((*prologue_pc & STK_ALLOC_1M) == STK_ALLOC_1M)
+                return -(((long)(*prologue_pc) << 48) >> 48);
+        else
+                return (*prologue_pc >> 13) & 0xff;
+}
+
+void
+stacktrace(void)
+{
+        instr * ret_pc;
+        instr * prologue = (instr *)stacktrace;
+        register unsigned char * sp __asm__ ("$30");
+
+        printk("\tstack trace:\n");
+        do {
+                ret_pc = display_stored_regs(prologue, sp);
+                sp += stack_increment(prologue);
+                prologue = seek_prologue(ret_pc);
+        } while (IS_KERNEL_TEXT(ret_pc));
+}