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| author | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2020-10-28 13:19:24 +0100 |
|---|---|---|
| committer | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2020-11-11 02:39:36 +0100 |
| commit | 60602cb549f1965a7edbc96026760dfb93911fab (patch) | |
| tree | a20295d7f8aa5216ff7a504d313b79f52adab181 | |
| parent | ftrace: Add recording of functions that caused recursion (diff) | |
| download | linux-60602cb549f1965a7edbc96026760dfb93911fab.tar.xz linux-60602cb549f1965a7edbc96026760dfb93911fab.zip | |
fgraph: Make overruns 4 bytes in graph stack structure
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>
| -rw-r--r-- | include/linux/ftrace.h | 4 | ||||
| -rw-r--r-- | kernel/trace/trace_entries.h | 4 | ||||
| -rw-r--r-- | kernel/trace/trace_functions_graph.c | 2 |
3 files changed, 5 insertions, 5 deletions
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 806196345c3f..8dde9c17aaa5 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -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*/ diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h index 18c4a58aff79..ceafe2dc97e1 100644 --- a/kernel/trace/trace_entries.h +++ b/kernel/trace/trace_entries.h @@ -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", diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index 60d66278aa0d..d874dec87131 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -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, |