dwarves_fprintf: Fixup cacheline boundary printing on expanded structs
A diff for 'pahole -EC task_struct vmlinux' should clarify what this fixes:
[acme@jouet linux]$ diff -u /tmp/before.c /tmp/after.c | head -30
--- /tmp/before.c 2016-06-29 17:00:38.082647281 -0300
+++ /tmp/a.c 2016-06-29 17:03:36.913124779 -0300
@@ -43,8 +43,8 @@
struct list_head * prev; /* 176 8 */
} group_node; /* 168 16 */
unsigned int on_rq; /* 184 4 */
+ /* --- cacheline 3 boundary (192 bytes) --- */
/* typedef u64 */ long long unsigned int exec_start; /* 192 8 */
- /* --- cacheline 1 boundary (64 bytes) was 4 bytes ago --- */
/* typedef u64 */ long long unsigned int sum_exec_runtime; /* 200 8 */
/* typedef u64 */ long long unsigned int vruntime; /* 208 8 */
/* typedef u64 */ long long unsigned int prev_sum_exec_runtime; /* 216 8 */
@@ -53,40 +53,40 @@
/* typedef u64 */ long long unsigned int wait_start; /* 232 8 */
/* typedef u64 */ long long unsigned int wait_max; /* 240 8 */
/* typedef u64 */ long long unsigned int wait_count; /* 248 8 */
+ /* --- cacheline 4 boundary (256 bytes) --- */
/* typedef u64 */ long long unsigned int wait_sum; /* 256 8 */
/* typedef u64 */ long long unsigned int iowait_count; /* 264 8 */
/* typedef u64 */ long long unsigned int iowait_sum; /* 272 8 */
/* typedef u64 */ long long unsigned int sleep_start; /* 280 8 */
/* typedef u64 */ long long unsigned int sleep_max; /* 288 8 */
- /* --- cacheline 1 boundary (64 bytes) --- */
/* typedef s64 */ long long int sum_sleep_runtime; /* 296 8 */
/* typedef u64 */ long long unsigned int block_start; /* 304 8 */
/* typedef u64 */ long long unsigned int block_max; /* 312 8 */
+ /* --- cacheline 5 boundary (320 bytes) --- */
/* typedef u64 */ long long unsigned int exec_max; /* 320 8 */
/* typedef u64 */ long long unsigned int slice_max; /* 328 8 */
/* typedef u64 */ long long unsigned int nr_migrations_cold; /* 336 8 */
[acme@jouet linux]$
I.e. the boundary detection was being reset at each expanded struct, do the math globally,
using the member offset, that was already done globally and correctly.
Reported-and-Tested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2 files changed
