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Diffstat (limited to 'arch/mips/kernel/ftrace.c')
-rw-r--r--arch/mips/kernel/ftrace.c93
1 files changed, 82 insertions, 11 deletions
diff --git a/arch/mips/kernel/ftrace.c b/arch/mips/kernel/ftrace.c
index 6a2d758dd8e..60e7e5e45af 100644
--- a/arch/mips/kernel/ftrace.c
+++ b/arch/mips/kernel/ftrace.c
@@ -11,11 +11,14 @@
#include <linux/uaccess.h>
#include <linux/init.h>
#include <linux/ftrace.h>
+#include <linux/syscalls.h>
#include <asm/asm.h>
#include <asm/asm-offsets.h>
#include <asm/cacheflush.h>
+#include <asm/syscall.h>
#include <asm/uasm.h>
+#include <asm/unistd.h>
#include <asm-generic/sections.h>
@@ -25,6 +28,16 @@
#define MCOUNT_OFFSET_INSNS 4
#endif
+#ifdef CONFIG_DYNAMIC_FTRACE
+
+/* Arch override because MIPS doesn't need to run this from stop_machine() */
+void arch_ftrace_update_code(int command)
+{
+ ftrace_modify_all_code(command);
+}
+
+#endif
+
/*
* Check if the address is in kernel space
*
@@ -77,6 +90,7 @@ static inline void ftrace_dyn_arch_init_insns(void)
static int ftrace_modify_code(unsigned long ip, unsigned int new_code)
{
int faulted;
+ mm_segment_t old_fs;
/* *(unsigned int *)ip = new_code; */
safe_store_code(new_code, ip, faulted);
@@ -84,10 +98,30 @@ static int ftrace_modify_code(unsigned long ip, unsigned int new_code)
if (unlikely(faulted))
return -EFAULT;
+ old_fs = get_fs();
+ set_fs(get_ds());
flush_icache_range(ip, ip + 8);
+ set_fs(old_fs);
+
+ return 0;
+}
+#ifndef CONFIG_64BIT
+static int ftrace_modify_code_2(unsigned long ip, unsigned int new_code1,
+ unsigned int new_code2)
+{
+ int faulted;
+
+ safe_store_code(new_code1, ip, faulted);
+ if (unlikely(faulted))
+ return -EFAULT;
+ safe_store_code(new_code2, ip + 4, faulted);
+ if (unlikely(faulted))
+ return -EFAULT;
+ flush_icache_range(ip, ip + 8);
return 0;
}
+#endif
/*
* The details about the calling site of mcount on MIPS
@@ -101,21 +135,21 @@ static int ftrace_modify_code(unsigned long ip, unsigned int new_code)
*
* 2.1 For KBUILD_MCOUNT_RA_ADDRESS and CONFIG_32BIT
*
- * lui v1, hi_16bit_of_mcount --> b 1f (0x10000005)
+ * lui v1, hi_16bit_of_mcount --> b 1f (0x10000005)
* addiu v1, v1, low_16bit_of_mcount
* move at, ra
* move $12, ra_address
* jalr v1
* sub sp, sp, 8
- * 1: offset = 5 instructions
+ * 1: offset = 5 instructions
* 2.2 For the Other situations
*
- * lui v1, hi_16bit_of_mcount --> b 1f (0x10000004)
+ * lui v1, hi_16bit_of_mcount --> b 1f (0x10000004)
* addiu v1, v1, low_16bit_of_mcount
* move at, ra
* jalr v1
* nop | move $12, ra_address | sub sp, sp, 8
- * 1: offset = 4 instructions
+ * 1: offset = 4 instructions
*/
#define INSN_B_1F (0x10000000 | MCOUNT_OFFSET_INSNS)
@@ -131,8 +165,18 @@ int ftrace_make_nop(struct module *mod,
* needed.
*/
new = in_kernel_space(ip) ? INSN_NOP : INSN_B_1F;
-
+#ifdef CONFIG_64BIT
return ftrace_modify_code(ip, new);
+#else
+ /*
+ * On 32 bit MIPS platforms, gcc adds a stack adjust
+ * instruction in the delay slot after the branch to
+ * mcount and expects mcount to restore the sp on return.
+ * This is based on a legacy API and does nothing but
+ * waste instructions so it's being removed at runtime.
+ */
+ return ftrace_modify_code_2(ip, new, INSN_NOP);
+#endif
}
int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
@@ -157,7 +201,7 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
return ftrace_modify_code(FTRACE_CALL_IP, new);
}
-int __init ftrace_dyn_arch_init(void *data)
+int __init ftrace_dyn_arch_init(void)
{
/* Encode the instructions when booting */
ftrace_dyn_arch_init_insns();
@@ -165,9 +209,6 @@ int __init ftrace_dyn_arch_init(void *data)
/* Remove "b ftrace_stub" to ensure ftrace_caller() is executed */
ftrace_modify_code(MCOUNT_ADDR, INSN_NOP);
- /* The return code is retured via data */
- *(unsigned long *)data = 0;
-
return 0;
}
#endif /* CONFIG_DYNAMIC_FTRACE */
@@ -194,8 +235,8 @@ int ftrace_disable_ftrace_graph_caller(void)
#ifndef KBUILD_MCOUNT_RA_ADDRESS
-#define S_RA_SP (0xafbf << 16) /* s{d,w} ra, offset(sp) */
-#define S_R_SP (0xafb0 << 16) /* s{d,w} R, offset(sp) */
+#define S_RA_SP (0xafbf << 16) /* s{d,w} ra, offset(sp) */
+#define S_R_SP (0xafb0 << 16) /* s{d,w} R, offset(sp) */
#define OFFSET_MASK 0xffff /* stack offset range: 0 ~ PT_SIZE */
unsigned long ftrace_get_parent_ra_addr(unsigned long self_ra, unsigned long
@@ -326,3 +367,33 @@ out:
WARN_ON(1);
}
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
+
+#ifdef CONFIG_FTRACE_SYSCALLS
+
+#ifdef CONFIG_32BIT
+unsigned long __init arch_syscall_addr(int nr)
+{
+ return (unsigned long)sys_call_table[nr - __NR_O32_Linux];
+}
+#endif
+
+#ifdef CONFIG_64BIT
+
+unsigned long __init arch_syscall_addr(int nr)
+{
+#ifdef CONFIG_MIPS32_N32
+ if (nr >= __NR_N32_Linux && nr <= __NR_N32_Linux + __NR_N32_Linux_syscalls)
+ return (unsigned long)sysn32_call_table[nr - __NR_N32_Linux];
+#endif
+ if (nr >= __NR_64_Linux && nr <= __NR_64_Linux + __NR_64_Linux_syscalls)
+ return (unsigned long)sys_call_table[nr - __NR_64_Linux];
+#ifdef CONFIG_MIPS32_O32
+ if (nr >= __NR_O32_Linux && nr <= __NR_O32_Linux + __NR_O32_Linux_syscalls)
+ return (unsigned long)sys32_call_table[nr - __NR_O32_Linux];
+#endif
+
+ return (unsigned long) &sys_ni_syscall;
+}
+#endif
+
+#endif /* CONFIG_FTRACE_SYSCALLS */