kprobes: Convert kprobe_lookup_name() to a function

The macro is now pretty long and ugly on powerpc. In the light of further
changes needed here, convert it to a __weak variant to be over-ridden with a
nicer looking function.

Suggested-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Naveen N. Rao
2017-04-19 18:21:00 +05:30
committed by Michael Ellerman
parent a460246c70
commit 49e0b4658f
5 changed files with 69 additions and 67 deletions

View File

@@ -61,59 +61,6 @@ extern kprobe_opcode_t optprobe_template_end[];
#define MAX_OPTINSN_SIZE (optprobe_template_end - optprobe_template_entry)
#define RELATIVEJUMP_SIZE sizeof(kprobe_opcode_t) /* 4 bytes */
#ifdef PPC64_ELF_ABI_v2
/* PPC64 ABIv2 needs local entry point */
#define kprobe_lookup_name(name, addr) \
{ \
addr = (kprobe_opcode_t *)kallsyms_lookup_name(name); \
if (addr) \
addr = (kprobe_opcode_t *)ppc_function_entry(addr); \
}
#elif defined(PPC64_ELF_ABI_v1)
/*
* 64bit powerpc ABIv1 uses function descriptors:
* - Check for the dot variant of the symbol first.
* - If that fails, try looking up the symbol provided.
*
* This ensures we always get to the actual symbol and not the descriptor.
* Also handle <module:symbol> format.
*/
#define kprobe_lookup_name(name, addr) \
{ \
char dot_name[MODULE_NAME_LEN + 1 + KSYM_NAME_LEN]; \
const char *modsym; \
bool dot_appended = false; \
if ((modsym = strchr(name, ':')) != NULL) { \
modsym++; \
if (*modsym != '\0' && *modsym != '.') { \
/* Convert to <module:.symbol> */ \
strncpy(dot_name, name, modsym - name); \
dot_name[modsym - name] = '.'; \
dot_name[modsym - name + 1] = '\0'; \
strncat(dot_name, modsym, \
sizeof(dot_name) - (modsym - name) - 2);\
dot_appended = true; \
} else { \
dot_name[0] = '\0'; \
strncat(dot_name, name, sizeof(dot_name) - 1); \
} \
} else if (name[0] != '.') { \
dot_name[0] = '.'; \
dot_name[1] = '\0'; \
strncat(dot_name, name, KSYM_NAME_LEN - 2); \
dot_appended = true; \
} else { \
dot_name[0] = '\0'; \
strncat(dot_name, name, KSYM_NAME_LEN - 1); \
} \
addr = (kprobe_opcode_t *)kallsyms_lookup_name(dot_name); \
if (!addr && dot_appended) { \
/* Let's try the original non-dot symbol lookup */ \
addr = (kprobe_opcode_t *)kallsyms_lookup_name(name); \
} \
}
#endif
#define flush_insn_slot(p) do { } while (0)
#define kretprobe_blacklist_size 0