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Subject[PATCH] ftrace: simplify hex print
simplify hex to ascii conversion with a lookup table.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

---
kernel/trace/trace.c | 23 +++++------------------
1 file changed, 5 insertions(+), 18 deletions(-)
Index: linux/kernel/trace/trace.c
===================================================================
--- linux.orig/kernel/trace/trace.c
+++ linux/kernel/trace/trace.c
@@ -248,19 +248,18 @@ trace_seq_putmem(struct trace_seq *s, vo
}

#define HEX_CHARS 17
+static const char hex2asc[] = "0123456789abcdef";

static int
trace_seq_putmem_hex(struct trace_seq *s, void *mem, size_t len)
{
unsigned char hex[HEX_CHARS];
- unsigned char *data;
+ unsigned char *data = mem;
unsigned char byte;
int i, j;

BUG_ON(len >= HEX_CHARS);

- data = mem;
-
#ifdef __BIG_ENDIAN
for (i = 0, j = 0; i < len; i++) {
#else
@@ -268,22 +267,10 @@ trace_seq_putmem_hex(struct trace_seq *s
#endif
byte = data[i];

- hex[j] = byte & 0x0f;
- if (hex[j] >= 10)
- hex[j] += 'a' - 10;
- else
- hex[j] += '0';
- j++;
-
- hex[j] = byte >> 4;
- if (hex[j] >= 10)
- hex[j] += 'a' - 10;
- else
- hex[j] += '0';
- j++;
+ hex[j++] = hex2asc[byte & 0x0f];
+ hex[j++] = hex2asc[byte >> 4];
}
- hex[j] = ' ';
- j++;
+ hex[j++] = ' ';

return trace_seq_putmem(s, hex, j);
}

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