Kernel/linux-next
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git synced 2025-01-06 05:02:31 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

fgraph: Make overruns 4 bytes in graph stack structure

Browse Source 
Inspecting the data structures of the function graph tracer, I found that
the overrun value is unsigned long, which is 8 bytes on a 64 bit machine,
and not only that, the depth is an int (4 bytes). The overrun can be simply
an unsigned int (4 bytes) and pack the ftrace_graph_ret structure better.

The depth is moved up next to the func, as it is used more often with func,
and improves cache locality.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt (VMware) 2020-10-28 08:19:24 -04:00
parent 773c167050
commit 60602cb549
3 changed files with 5 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
include/linux/ftrace.h
View File

@ -864,11 +864,11 @@ struct ftrace_graph_ent {
*/
struct ftrace_graph_ret {
unsigned long func; /* Current function */
int depth;
/* Number of functions that overran the depth limit for current task */
unsigned long overrun;
unsigned int overrun;
unsigned long long calltime;
unsigned long long rettime;
int depth;
} __packed;
/* Type of the callback handlers for tracing function graph*/

4
kernel/trace/trace_entries.h
View File

@ -93,10 +93,10 @@ FTRACE_ENTRY_PACKED(funcgraph_exit, ftrace_graph_ret_entry,
F_STRUCT(
__field_struct( struct ftrace_graph_ret, ret )
__field_packed( unsigned long, ret, func )
__field_packed( unsigned long, ret, overrun )
__field_packed( int, ret, depth )
__field_packed( unsigned int, ret, overrun )
__field_packed( unsigned long long, ret, calltime)
__field_packed( unsigned long long, ret, rettime )
__field_packed( int, ret, depth )
),
F_printk("<-- %ps (%d) (start: %llx end: %llx) over: %d",

2
kernel/trace/trace_functions_graph.c
View File

@ -957,7 +957,7 @@ print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
/* Overrun */
if (flags & TRACE_GRAPH_PRINT_OVERRUN)
trace_seq_printf(s, " (Overruns: %lu)\n",
trace_seq_printf(s, " (Overruns: %u)\n",
trace->overrun);
print_graph_irq(iter, trace->func, TRACE_GRAPH_RET,