vsprintf: Add extension %pSR - print_symbol replacement

print_symbol takes a long and converts it to a function
name and offset.  %pS does something similar, but doesn't
translate the address via __builtin_extract_return_addr.
%pSR does the translation.

This will enable replacing multiple calls like
	printk(...);
	printk_symbol(addr);
	printk("\n");
with a single non-interleavable in dmesg
	printk("... %pSR\n", (void *)addr);

Update documentation too.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This commit is contained in:
Joe Perches 2012-12-12 10:18:50 -08:00 committed by Jiri Kosina
parent 071361d347
commit b0d33c2bd7
2 changed files with 15 additions and 5 deletions

View File

@ -17,6 +17,8 @@ Symbols/Function Pointers:
%pF versatile_init+0x0/0x110
%pf versatile_init
%pS versatile_init+0x0/0x110
%pSR versatile_init+0x9/0x110
(with __builtin_extract_return_addr() translation)
%ps versatile_init
%pB prev_fn_of_versatile_init+0x88/0x88

View File

@ -534,14 +534,21 @@ char *string(char *buf, char *end, const char *s, struct printf_spec spec)
static noinline_for_stack
char *symbol_string(char *buf, char *end, void *ptr,
struct printf_spec spec, char ext)
struct printf_spec spec, const char *fmt)
{
unsigned long value = (unsigned long) ptr;
unsigned long value;
#ifdef CONFIG_KALLSYMS
char sym[KSYM_SYMBOL_LEN];
if (ext == 'B')
#endif
if (fmt[1] == 'R')
ptr = __builtin_extract_return_addr(ptr);
value = (unsigned long)ptr;
#ifdef CONFIG_KALLSYMS
if (*fmt == 'B')
sprint_backtrace(sym, value);
else if (ext != 'f' && ext != 's')
else if (*fmt != 'f' && *fmt != 's')
sprint_symbol(sym, value);
else
sprint_symbol_no_offset(sym, value);
@ -987,6 +994,7 @@ int kptr_restrict __read_mostly;
* - 'f' For simple symbolic function names without offset
* - 'S' For symbolic direct pointers with offset
* - 's' For symbolic direct pointers without offset
* - '[FfSs]R' as above with __builtin_extract_return_addr() translation
* - 'B' For backtraced symbolic direct pointers with offset
* - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
* - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
@ -1060,7 +1068,7 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr,
case 'S':
case 's':
case 'B':
return symbol_string(buf, end, ptr, spec, *fmt);
return symbol_string(buf, end, ptr, spec, fmt);
case 'R':
case 'r':
return resource_string(buf, end, ptr, spec, fmt);