ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/arch/arm/kernel/ftrace.c b/marvell/linux/arch/arm/kernel/ftrace.c
new file mode 100644
index 0000000..2049603
--- /dev/null
+++ b/marvell/linux/arch/arm/kernel/ftrace.c
@@ -0,0 +1,338 @@
+/*
+ * Dynamic function tracing support.
+ *
+ * Copyright (C) 2008 Abhishek Sagar <sagar.abhishek@gmail.com>
+ * Copyright (C) 2010 Rabin Vincent <rabin@rab.in>
+ *
+ * For licencing details, see COPYING.
+ *
+ * Defines low-level handling of mcount calls when the kernel
+ * is compiled with the -pg flag. When using dynamic ftrace, the
+ * mcount call-sites get patched with NOP till they are enabled.
+ * All code mutation routines here are called under stop_machine().
+ */
+
+#include <linux/ftrace.h>
+#include <linux/uaccess.h>
+#include <linux/module.h>
+#include <linux/stop_machine.h>
+
+#include <asm/cacheflush.h>
+#include <asm/opcodes.h>
+#include <asm/ftrace.h>
+#include <asm/insn.h>
+#include <asm/set_memory.h>
+#include <asm/stacktrace.h>
+
+/*
+ * The compiler emitted profiling hook consists of
+ *
+ * PUSH {LR}
+ * BL __gnu_mcount_nc
+ *
+ * To turn this combined sequence into a NOP, we need to restore the value of
+ * SP before the PUSH. Let's use an ADD rather than a POP into LR, as LR is not
+ * modified anyway, and reloading LR from memory is highly likely to be less
+ * efficient.
+ */
+#ifdef CONFIG_THUMB2_KERNEL
+#define NOP 0xf10d0d04 /* add.w sp, sp, #4 */
+#else
+#define NOP 0xe28dd004 /* add sp, sp, #4 */
+#endif
+
+#ifdef CONFIG_DYNAMIC_FTRACE
+
+static int __ftrace_modify_code(void *data)
+{
+ int *command = data;
+
+ set_kernel_text_rw();
+ ftrace_modify_all_code(*command);
+ set_kernel_text_ro();
+
+ return 0;
+}
+
+void arch_ftrace_update_code(int command)
+{
+ stop_machine(__ftrace_modify_code, &command, NULL);
+}
+
+static unsigned long ftrace_nop_replace(struct dyn_ftrace *rec)
+{
+ return NOP;
+}
+
+void ftrace_caller_from_init(void);
+void ftrace_regs_caller_from_init(void);
+
+static unsigned long __ref adjust_address(struct dyn_ftrace *rec,
+ unsigned long addr)
+{
+ if (!IS_ENABLED(CONFIG_DYNAMIC_FTRACE) ||
+ system_state >= SYSTEM_FREEING_INITMEM ||
+ likely(!is_kernel_inittext(rec->ip)))
+ return addr;
+ if (!IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_REGS) ||
+ addr == (unsigned long)&ftrace_caller)
+ return (unsigned long)&ftrace_caller_from_init;
+ return (unsigned long)&ftrace_regs_caller_from_init;
+}
+
+int ftrace_arch_code_modify_prepare(void)
+{
+ set_all_modules_text_rw();
+ return 0;
+}
+
+int ftrace_arch_code_modify_post_process(void)
+{
+ set_all_modules_text_ro();
+ /* Make sure any TLB misses during machine stop are cleared. */
+ flush_tlb_all();
+ return 0;
+}
+
+static unsigned long ftrace_call_replace(unsigned long pc, unsigned long addr,
+ bool warn)
+{
+ return arm_gen_branch_link(pc, addr, warn);
+}
+
+static int ftrace_modify_code(unsigned long pc, unsigned long old,
+ unsigned long new, bool validate)
+{
+ unsigned long replaced;
+
+ if (IS_ENABLED(CONFIG_THUMB2_KERNEL)) {
+ old = __opcode_to_mem_thumb32(old);
+ new = __opcode_to_mem_thumb32(new);
+ } else {
+ old = __opcode_to_mem_arm(old);
+ new = __opcode_to_mem_arm(new);
+ }
+
+ if (validate) {
+ if (probe_kernel_read(&replaced, (void *)pc, MCOUNT_INSN_SIZE))
+ return -EFAULT;
+
+ if (replaced != old)
+ return -EINVAL;
+ }
+
+ if (probe_kernel_write((void *)pc, &new, MCOUNT_INSN_SIZE))
+ return -EPERM;
+
+ flush_icache_range(pc, pc + MCOUNT_INSN_SIZE);
+
+ return 0;
+}
+
+int ftrace_update_ftrace_func(ftrace_func_t func)
+{
+ unsigned long pc;
+ unsigned long new;
+ int ret;
+
+ pc = (unsigned long)&ftrace_call;
+ new = ftrace_call_replace(pc, (unsigned long)func, true);
+
+ ret = ftrace_modify_code(pc, 0, new, false);
+
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
+ if (!ret) {
+ pc = (unsigned long)&ftrace_regs_call;
+ new = ftrace_call_replace(pc, (unsigned long)func, true);
+
+ ret = ftrace_modify_code(pc, 0, new, false);
+ }
+#endif
+
+ return ret;
+}
+
+int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
+{
+ unsigned long new, old;
+ unsigned long ip = rec->ip;
+ unsigned long aaddr = adjust_address(rec, addr);
+ struct module *mod = NULL;
+
+#ifdef CONFIG_ARM_MODULE_PLTS
+ mod = rec->arch.mod;
+#endif
+
+ old = ftrace_nop_replace(rec);
+
+ new = ftrace_call_replace(ip, aaddr, !mod);
+#ifdef CONFIG_ARM_MODULE_PLTS
+ if (!new && mod) {
+ aaddr = get_module_plt(mod, ip, aaddr);
+ new = ftrace_call_replace(ip, aaddr, true);
+ }
+#endif
+
+ return ftrace_modify_code(rec->ip, old, new, true);
+}
+
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
+
+int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
+ unsigned long addr)
+{
+ unsigned long new, old;
+ unsigned long ip = rec->ip;
+
+ old = ftrace_call_replace(ip, adjust_address(rec, old_addr), true);
+
+ new = ftrace_call_replace(ip, adjust_address(rec, addr), true);
+
+ return ftrace_modify_code(rec->ip, old, new, true);
+}
+
+#endif
+
+int ftrace_make_nop(struct module *mod,
+ struct dyn_ftrace *rec, unsigned long addr)
+{
+ unsigned long aaddr = adjust_address(rec, addr);
+ unsigned long ip = rec->ip;
+ unsigned long old;
+ unsigned long new;
+ int ret;
+
+#ifdef CONFIG_ARM_MODULE_PLTS
+ /* mod is only supplied during module loading */
+ if (!mod)
+ mod = rec->arch.mod;
+ else
+ rec->arch.mod = mod;
+#endif
+
+ old = ftrace_call_replace(ip, aaddr,
+ !IS_ENABLED(CONFIG_ARM_MODULE_PLTS) || !mod);
+#ifdef CONFIG_ARM_MODULE_PLTS
+ if (!old && mod) {
+ aaddr = get_module_plt(mod, ip, aaddr);
+ old = ftrace_call_replace(ip, aaddr, true);
+ }
+#endif
+
+ new = ftrace_nop_replace(rec);
+ /*
+ * Locations in .init.text may call __gnu_mcount_mc via a linker
+ * emitted veneer if they are too far away from its implementation, and
+ * so validation may fail spuriously in such cases. Let's work around
+ * this by omitting those from validation.
+ */
+ ret = ftrace_modify_code(ip, old, new, !is_kernel_inittext(ip));
+
+ return ret;
+}
+
+int __init ftrace_dyn_arch_init(void)
+{
+ return 0;
+}
+#endif /* CONFIG_DYNAMIC_FTRACE */
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+asmlinkage
+void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr,
+ unsigned long frame_pointer,
+ unsigned long stack_pointer)
+{
+ unsigned long return_hooker = (unsigned long) &return_to_handler;
+ unsigned long old;
+
+ if (unlikely(atomic_read(¤t->tracing_graph_pause)))
+err_out:
+ return;
+
+ if (IS_ENABLED(CONFIG_UNWINDER_FRAME_POINTER)) {
+ /*
+ * Usually, the stack frames are contiguous in memory but cases
+ * have been observed where the next stack frame does not live
+ * at 'frame_pointer + 4' as this code used to assume.
+ *
+ * Instead, dereference the field in the stack frame that
+ * stores the SP of the calling frame: to avoid unbounded
+ * recursion, this cannot involve any ftrace instrumented
+ * functions, so use the __get_kernel_nofault() primitive
+ * directly.
+ */
+ __get_kernel_nofault(&frame_pointer,
+ (unsigned long *)(frame_pointer - 8),
+ unsigned long, err_out);
+ } else {
+ struct stackframe frame = {
+ .fp = frame_pointer,
+ .sp = stack_pointer,
+ .lr = self_addr,
+ .pc = self_addr,
+ };
+ if (unwind_frame(&frame) < 0)
+ return;
+ if (frame.lr != self_addr)
+ parent = frame.lr_addr;
+ frame_pointer = frame.sp;
+ }
+
+ old = *parent;
+ *parent = return_hooker;
+
+ if (function_graph_enter(old, self_addr, frame_pointer, NULL))
+ *parent = old;
+}
+
+#ifdef CONFIG_DYNAMIC_FTRACE
+extern unsigned long ftrace_graph_call;
+extern unsigned long ftrace_graph_call_old;
+extern void ftrace_graph_caller_old(void);
+extern unsigned long ftrace_graph_regs_call;
+extern void ftrace_graph_regs_caller(void);
+
+static int __ftrace_modify_caller(unsigned long *callsite,
+ void (*func) (void), bool enable)
+{
+ unsigned long caller_fn = (unsigned long) func;
+ unsigned long pc = (unsigned long) callsite;
+ unsigned long branch = arm_gen_branch(pc, caller_fn);
+ unsigned long nop = arm_gen_nop();
+ unsigned long old = enable ? nop : branch;
+ unsigned long new = enable ? branch : nop;
+
+ return ftrace_modify_code(pc, old, new, true);
+}
+
+static int ftrace_modify_graph_caller(bool enable)
+{
+ int ret;
+
+ ret = __ftrace_modify_caller(&ftrace_graph_call,
+ ftrace_graph_caller,
+ enable);
+
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
+ if (!ret)
+ ret = __ftrace_modify_caller(&ftrace_graph_regs_call,
+ ftrace_graph_regs_caller,
+ enable);
+#endif
+
+
+ return ret;
+}
+
+int ftrace_enable_ftrace_graph_caller(void)
+{
+ return ftrace_modify_graph_caller(true);
+}
+
+int ftrace_disable_ftrace_graph_caller(void)
+{
+ return ftrace_modify_graph_caller(false);
+}
+#endif /* CONFIG_DYNAMIC_FTRACE */
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */