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kernel/trace: extract common part in process_fetch_insn

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Each probe has an instance of process_fetch_insn respectively,
but they have something in common.

This patch aims to extract the common part into
process_common_fetch_insn which can be shared by each probe,
and they only need to focus on their special cases.

Signed-off-by: Song Chen <chensong_2000@189.cn>
Suggested-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
This commit is contained in:
Song Chen 2022-12-30 14:33:53 +08:00 committed by Masami Hiramatsu (Google)
parent 672a2bf840
commit bd78acc89d
4 changed files with 34 additions and 37 deletions
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26
kernel/trace/trace_eprobe.c
View file

@ -396,20 +396,12 @@ static int get_eprobe_size(struct trace_probe *tp, void *rec)
case FETCH_OP_TP_ARG:
val = get_event_field(code, rec);
break;
case FETCH_OP_IMM:
val = code->immediate;
break;
case FETCH_OP_COMM:
val = (unsigned long)current->comm;
break;
case FETCH_OP_DATA:
val = (unsigned long)code->data;
break;
case FETCH_NOP_SYMBOL: /* Ignore a place holder */
code++;
goto retry;
default:
continue;
if (process_common_fetch_insn(code, &val) < 0)
continue;
}
code++;
len = process_fetch_insn_bottom(code, val, NULL, NULL);
@ -429,26 +421,20 @@ process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
void *base)
{
unsigned long val;
int ret;
retry:
switch (code->op) {
case FETCH_OP_TP_ARG:
val = get_event_field(code, rec);
break;
case FETCH_OP_IMM:
val = code->immediate;
break;
case FETCH_OP_COMM:
val = (unsigned long)current->comm;
break;
case FETCH_OP_DATA:
val = (unsigned long)code->data;
break;
case FETCH_NOP_SYMBOL: /* Ignore a place holder */
code++;
goto retry;
default:
return -EILSEQ;
ret = process_common_fetch_insn(code, &val);
if (ret < 0)
return ret;
}
code++;
return process_fetch_insn_bottom(code, val, dest, base);

14
kernel/trace/trace_kprobe.c
View file

@ -1225,6 +1225,7 @@ process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
{
struct pt_regs *regs = rec;
unsigned long val;
int ret;
retry:
/* 1st stage: get value from context */
@ -1241,15 +1242,6 @@ process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
case FETCH_OP_RETVAL:
val = regs_return_value(regs);
break;
case FETCH_OP_IMM:
val = code->immediate;
break;
case FETCH_OP_COMM:
val = (unsigned long)current->comm;
break;
case FETCH_OP_DATA:
val = (unsigned long)code->data;
break;
#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
case FETCH_OP_ARG:
val = regs_get_kernel_argument(regs, code->param);
@ -1259,7 +1251,9 @@ process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
code++;
goto retry;
default:
return -EILSEQ;
ret = process_common_fetch_insn(code, &val);
if (ret < 0)
return ret;
}
code++;

20
kernel/trace/trace_probe_tmpl.h
View file

@ -98,6 +98,26 @@ fetch_store_symstring(unsigned long addr, void *dest, void *base)
return sprint_symbol(__dest, addr);
}
/* common part of process_fetch_insn*/
static nokprobe_inline int
process_common_fetch_insn(struct fetch_insn *code, unsigned long *val)
{
switch (code->op) {
case FETCH_OP_IMM:
*val = code->immediate;
break;
case FETCH_OP_COMM:
*val = (unsigned long)current->comm;
break;
case FETCH_OP_DATA:
*val = (unsigned long)code->data;
break;
default:
return -EILSEQ;
}
return 0;
}
/* From the 2nd stage, routine is same */
static nokprobe_inline int
process_fetch_insn_bottom(struct fetch_insn *code, unsigned long val,

11
kernel/trace/trace_uprobe.c
View file

@ -220,6 +220,7 @@ process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
{
struct pt_regs *regs = rec;
unsigned long val;
int ret;
/* 1st stage: get value from context */
switch (code->op) {
@ -235,20 +236,16 @@ process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
case FETCH_OP_RETVAL:
val = regs_return_value(regs);
break;
case FETCH_OP_IMM:
val = code->immediate;
break;
case FETCH_OP_COMM:
val = FETCH_TOKEN_COMM;
break;
case FETCH_OP_DATA:
val = (unsigned long)code->data;
break;
case FETCH_OP_FOFFS:
val = translate_user_vaddr(code->immediate);
break;
default:
return -EILSEQ;
ret = process_common_fetch_insn(code, &val);
if (ret < 0)
return ret;
}
code++;