Add objtool --stats to count the jump_label sites it encounters.
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
---
tools/objtool/check.c | 22 ++++++++++++++++++++--
tools/objtool/include/objtool/objtool.h | 3 +++
2 files changed, 23 insertions(+), 2 deletions(-)
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -1225,8 +1225,15 @@ static int handle_jump_alt(struct objtoo
struct instruction *orig_insn,
struct instruction **new_insn)
{
- if (orig_insn->type == INSN_NOP)
+ if (orig_insn->type == INSN_NOP) {
+do_nop:
+ if (orig_insn->len == 2)
+ file->jl_nop_short++;
+ else
+ file->jl_nop_long++;
+
return 0;
+ }
if (orig_insn->type != INSN_JUMP_UNCONDITIONAL) {
WARN_FUNC("unsupported instruction at jump label",
@@ -1245,9 +1252,14 @@ static int handle_jump_alt(struct objtoo
orig_insn->offset, orig_insn->len,
arch_nop_insn(orig_insn->len));
orig_insn->type = INSN_NOP;
- return 0;
+ goto do_nop;
}
+ if (orig_insn->len == 2)
+ file->jl_short++;
+ else
+ file->jl_long++;
+
*new_insn = list_next_entry(orig_insn, list);
return 0;
}
@@ -1328,6 +1340,12 @@ static int add_special_section_alts(stru
free(special_alt);
}
+ if (stats) {
+ printf("jl\\\tNOP\tJMP\n");
+ printf("short:\t%ld\t%ld\n", file->jl_nop_short, file->jl_short);
+ printf("long:\t%ld\t%ld\n", file->jl_nop_long, file->jl_long);
+ }
+
out:
return ret;
}
--- a/tools/objtool/include/objtool/objtool.h
+++ b/tools/objtool/include/objtool/objtool.h
@@ -22,6 +22,9 @@ struct objtool_file {
struct list_head static_call_list;
struct list_head mcount_loc_list;
bool ignore_unreachables, c_file, hints, rodata;
+
+ unsigned long jl_short, jl_long;
+ unsigned long jl_nop_short, jl_nop_long;
};
struct objtool_file *objtool_open_read(const char *_objname);
The following commit has been merged into the objtool/core branch of tip:
Commit-ID: e2d9494beff21a26438eb611c260b8a6c2dc4dbf
Gitweb: https://git.kernel.org/tip/e2d9494beff21a26438eb611c260b8a6c2dc4dbf
Author: Peter Zijlstra <[email protected]>
AuthorDate: Thu, 06 May 2021 21:34:04 +02:00
Committer: Ingo Molnar <[email protected]>
CommitterDate: Wed, 12 May 2021 14:54:56 +02:00
objtool: Provide stats for jump_labels
Add objtool --stats to count the jump_label sites it encounters.
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
---
tools/objtool/check.c | 22 ++++++++++++++++++++--
tools/objtool/include/objtool/objtool.h | 3 +++
2 files changed, 23 insertions(+), 2 deletions(-)
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 98cf87f..2c6a93e 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -1225,8 +1225,15 @@ static int handle_jump_alt(struct objtool_file *file,
struct instruction *orig_insn,
struct instruction **new_insn)
{
- if (orig_insn->type == INSN_NOP)
+ if (orig_insn->type == INSN_NOP) {
+do_nop:
+ if (orig_insn->len == 2)
+ file->jl_nop_short++;
+ else
+ file->jl_nop_long++;
+
return 0;
+ }
if (orig_insn->type != INSN_JUMP_UNCONDITIONAL) {
WARN_FUNC("unsupported instruction at jump label",
@@ -1245,9 +1252,14 @@ static int handle_jump_alt(struct objtool_file *file,
orig_insn->offset, orig_insn->len,
arch_nop_insn(orig_insn->len));
orig_insn->type = INSN_NOP;
- return 0;
+ goto do_nop;
}
+ if (orig_insn->len == 2)
+ file->jl_short++;
+ else
+ file->jl_long++;
+
*new_insn = list_next_entry(orig_insn, list);
return 0;
}
@@ -1328,6 +1340,12 @@ static int add_special_section_alts(struct objtool_file *file)
free(special_alt);
}
+ if (stats) {
+ printf("jl\\\tNOP\tJMP\n");
+ printf("short:\t%ld\t%ld\n", file->jl_nop_short, file->jl_short);
+ printf("long:\t%ld\t%ld\n", file->jl_nop_long, file->jl_long);
+ }
+
out:
return ret;
}
diff --git a/tools/objtool/include/objtool/objtool.h b/tools/objtool/include/objtool/objtool.h
index e4084af..24fa836 100644
--- a/tools/objtool/include/objtool/objtool.h
+++ b/tools/objtool/include/objtool/objtool.h
@@ -22,6 +22,9 @@ struct objtool_file {
struct list_head static_call_list;
struct list_head mcount_loc_list;
bool ignore_unreachables, c_file, hints, rodata;
+
+ unsigned long jl_short, jl_long;
+ unsigned long jl_nop_short, jl_nop_long;
};
struct objtool_file *objtool_open_read(const char *_objname);
Subject: objtool: Reflow handle_jump_alt()
From: Peter Zijlstra <[email protected]>
Date: Thu May 13 13:52:46 CEST 2021
Miroslav figured the code flow in handle_jump_alt() was sub-optimal
with that goto. Reflow the code to make it clearer.
Reported-by: Miroslav Benes <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
---
tools/objtool/check.c | 22 +++++++++++-----------
1 file changed, 11 insertions(+), 11 deletions(-)
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -1225,17 +1225,9 @@ static int handle_jump_alt(struct objtoo
struct instruction *orig_insn,
struct instruction **new_insn)
{
- if (orig_insn->type == INSN_NOP) {
-do_nop:
- if (orig_insn->len == 2)
- file->jl_nop_short++;
- else
- file->jl_nop_long++;
+ if (orig_insn->type != INSN_JUMP_UNCONDITIONAL &&
+ orig_insn->type != INSN_NOP) {
- return 0;
- }
-
- if (orig_insn->type != INSN_JUMP_UNCONDITIONAL) {
WARN_FUNC("unsupported instruction at jump label",
orig_insn->sec, orig_insn->offset);
return -1;
@@ -1252,7 +1244,15 @@ static int handle_jump_alt(struct objtoo
orig_insn->offset, orig_insn->len,
arch_nop_insn(orig_insn->len));
orig_insn->type = INSN_NOP;
- goto do_nop;
+ }
+
+ if (orig_insn->type == INSN_NOP) {
+ if (orig_insn->len == 2)
+ file->jl_nop_short++;
+ else
+ file->jl_nop_long++;
+
+ return 0;
}
if (orig_insn->len == 2)