diff options
| author | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2019-04-22 17:41:44 -0400 |
|---|---|---|
| committer | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2021-04-15 19:28:13 -0400 |
| commit | af135865534e79074152c9939d2083fce5931fe1 (patch) | |
| tree | a128237ae1dea2a7318f354cf56d8457095063f1 | |
| parent | ec4e4edaabaa8fed083e5462662dfb2a5d4dbd01 (diff) | |
| download | linux-trace-af135865534e79074152c9939d2083fce5931fe1.tar.gz | |
function_graph: Move graph notrace bit to shadow stack global var
The use of the task->trace_recursion for the logic used for the function
graph no-trace was a bit of an abuse of that variable. Now that there exists
global vars that are per stack for registered graph traces, use that instead.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| -rw-r--r-- | kernel/trace/trace.h | 9 | ||||
| -rw-r--r-- | kernel/trace/trace_functions_graph.c | 10 |
2 files changed, 15 insertions, 4 deletions
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 90dcef6846aa1..78a5312f7ecdf 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -847,8 +847,17 @@ enum { TRACE_GRAPH_DEPTH_START_BIT, TRACE_GRAPH_DEPTH_END_BIT, + + /* + * To implement set_graph_notrace, if this bit is set, we ignore + * function graph tracing of called functions, until the return + * function is called to clear it. + */ + TRACE_GRAPH_NOTRACE_BIT, }; +#define TRACE_GRAPH_NOTRACE (1 << TRACE_GRAPH_NOTRACE_BIT) + static inline unsigned long ftrace_graph_depth(unsigned long *task_var) { return (*task_var >> TRACE_GRAPH_DEPTH_START_BIT) & 3; diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index 0b3c7f33d1396..93e8c350fa6ee 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -124,6 +124,7 @@ static inline int ftrace_graph_ignore_irqs(void) int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops) { + unsigned long *task_var = fgraph_get_task_var(gops); struct trace_array *tr = gops->private; struct trace_array_cpu *data; unsigned long flags; @@ -132,7 +133,7 @@ int trace_graph_entry(struct ftrace_graph_ent *trace, int ret; int cpu; - if (trace_recursion_test(TRACE_GRAPH_NOTRACE_BIT)) + if (*task_var & TRACE_GRAPH_NOTRACE) return 0; /* @@ -143,7 +144,7 @@ int trace_graph_entry(struct ftrace_graph_ent *trace, * returning from the function. */ if (ftrace_graph_notrace_addr(trace->func)) { - trace_recursion_set(TRACE_GRAPH_NOTRACE_BIT); + *task_var |= TRACE_GRAPH_NOTRACE_BIT; /* * Need to return 1 to have the return called * that will clear the NOTRACE bit. @@ -234,6 +235,7 @@ void __trace_graph_return(struct trace_array *tr, void trace_graph_return(struct ftrace_graph_ret *trace, struct fgraph_ops *gops) { + unsigned long *task_var = fgraph_get_task_var(gops); struct trace_array *tr = gops->private; struct trace_array_cpu *data; unsigned long flags; @@ -243,8 +245,8 @@ void trace_graph_return(struct ftrace_graph_ret *trace, ftrace_graph_addr_finish(gops, trace); - if (trace_recursion_test(TRACE_GRAPH_NOTRACE_BIT)) { - trace_recursion_clear(TRACE_GRAPH_NOTRACE_BIT); + if (*task_var & TRACE_GRAPH_NOTRACE) { + *task_var &= ~TRACE_GRAPH_NOTRACE; return; } |