Avoid 6 byte hole for padding. Place more frequently used fields
first in an attempt to use just 1 cacheline in the common case.
Before:
```
struct callchain_list {
u64 ip; /* 0 8 */
struct map_symbol ms; /* 8 24 */
struct {
_Bool unfolded; /* 32 1 */
_Bool has_children; /* 33 1 */
}; /* 32 2 */
/* XXX 6 bytes hole, try to pack */
u64 branch_count; /* 40 8 */
u64 from_count; /* 48 8 */
u64 predicted_count; /* 56 8 */
/* --- cacheline 1 boundary (64 bytes) --- */
u64 abort_count; /* 64 8 */
u64 cycles_count; /* 72 8 */
u64 iter_count; /* 80 8 */
u64 iter_cycles; /* 88 8 */
struct branch_type_stat * brtype_stat; /* 96 8 */
const char * srcline; /* 104 8 */
struct list_head list; /* 112 16 */
/* size: 128, cachelines: 2, members: 13 */
/* sum members: 122, holes: 1, sum holes: 6 */
};
```
After:
```
struct callchain_list {
struct list_head list; /* 0 16 */
u64 ip; /* 16 8 */
struct map_symbol ms; /* 24 24 */
const char * srcline; /* 48 8 */
u64 branch_count; /* 56 8 */
/* --- cacheline 1 boundary (64 bytes) --- */
u64 from_count; /* 64 8 */
u64 cycles_count; /* 72 8 */
u64 iter_count; /* 80 8 */
u64 iter_cycles; /* 88 8 */
struct branch_type_stat * brtype_stat; /* 96 8 */
u64 predicted_count; /* 104 8 */
u64 abort_count; /* 112 8 */
struct {
_Bool unfolded; /* 120 1 */
_Bool has_children; /* 121 1 */
}; /* 120 2 */
/* size: 128, cachelines: 2, members: 13 */
/* padding: 6 */
};
```
Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/perf/util/callchain.h | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/tools/perf/util/callchain.h b/tools/perf/util/callchain.h
index 86e8a9e81456..d5c66345ae31 100644
--- a/tools/perf/util/callchain.h
+++ b/tools/perf/util/callchain.h
@@ -116,22 +116,22 @@ extern struct callchain_param callchain_param;
extern struct callchain_param callchain_param_default;
struct callchain_list {
+ struct list_head list;
u64 ip;
struct map_symbol ms;
- struct /* for TUI */ {
- bool unfolded;
- bool has_children;
- };
+ const char *srcline;
u64 branch_count;
u64 from_count;
- u64 predicted_count;
- u64 abort_count;
u64 cycles_count;
u64 iter_count;
u64 iter_cycles;
struct branch_type_stat *brtype_stat;
- const char *srcline;
- struct list_head list;
+ u64 predicted_count;
+ u64 abort_count;
+ struct /* for TUI */ {
+ bool unfolded;
+ bool has_children;
+ };
};
/*
--
2.42.0.609.gbb76f46606-goog
