From: Steven Rostedt <[email protected]>

Currently the option to have function graph tracer to ignore time spent
when a task is sleeping is global when the interface is per-instance.
Changing the value in one instance will affect the results of another
instance that is also running the function graph tracer. This can lead to
confusing results.

Fixes: c132be2c4fcc1 ("function_graph: Have the instances use their own 
ftrace_ops for filtering")
Signed-off-by: Steven Rostedt (Google) <[email protected]>
---
 kernel/trace/fgraph.c                | 10 +----
 kernel/trace/ftrace.c                |  4 +-
 kernel/trace/trace.h                 |  5 +--
 kernel/trace/trace_functions_graph.c | 64 +++++++++++++++++++++++-----
 4 files changed, 60 insertions(+), 23 deletions(-)

diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c
index 484ad7a18463..7fb9b169d6d4 100644
--- a/kernel/trace/fgraph.c
+++ b/kernel/trace/fgraph.c
@@ -498,9 +498,6 @@ void *fgraph_retrieve_parent_data(int idx, int *size_bytes, 
int depth)
        return get_data_type_data(current, offset);
 }
 
-/* Both enabled by default (can be cleared by function_graph tracer flags */
-bool fgraph_sleep_time = true;
-
 #ifdef CONFIG_DYNAMIC_FTRACE
 /*
  * archs can override this function if they must do something
@@ -1023,11 +1020,6 @@ void fgraph_init_ops(struct ftrace_ops *dst_ops,
 #endif
 }
 
-void ftrace_graph_sleep_time_control(bool enable)
-{
-       fgraph_sleep_time = enable;
-}
-
 /*
  * Simply points to ftrace_stub, but with the proper protocol.
  * Defined by the linker script in linux/vmlinux.lds.h
@@ -1098,7 +1090,7 @@ ftrace_graph_probe_sched_switch(void *ignore, bool 
preempt,
         * Does the user want to count the time a function was asleep.
         * If so, do not update the time stamps.
         */
-       if (fgraph_sleep_time)
+       if (!fgraph_no_sleep_time)
                return;
 
        timestamp = trace_clock_local();
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index ab601cd9638b..7c3bbebeec7a 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -862,6 +862,8 @@ static int profile_graph_entry(struct ftrace_graph_ent 
*trace,
        return 1;
 }
 
+bool fprofile_no_sleep_time;
+
 static void profile_graph_return(struct ftrace_graph_ret *trace,
                                 struct fgraph_ops *gops,
                                 struct ftrace_regs *fregs)
@@ -887,7 +889,7 @@ static void profile_graph_return(struct ftrace_graph_ret 
*trace,
 
        calltime = rettime - profile_data->calltime;
 
-       if (!fgraph_sleep_time) {
+       if (fprofile_no_sleep_time) {
                if (current->ftrace_sleeptime)
                        calltime -= current->ftrace_sleeptime - 
profile_data->sleeptime;
        }
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 41b416a22450..58be6d741d72 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -943,8 +943,6 @@ static __always_inline bool ftrace_hash_empty(struct 
ftrace_hash *hash)
 #define TRACE_GRAPH_PRINT_FILL_SHIFT   28
 #define TRACE_GRAPH_PRINT_FILL_MASK    (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
 
-extern void ftrace_graph_sleep_time_control(bool enable);
-
 #ifdef CONFIG_FUNCTION_PROFILER
 extern void ftrace_graph_graph_time_control(bool enable);
 #else
@@ -1115,7 +1113,8 @@ static inline void ftrace_graph_addr_finish(struct 
fgraph_ops *gops, struct ftra
 #endif /* CONFIG_DYNAMIC_FTRACE */
 
 extern unsigned int fgraph_max_depth;
-extern bool fgraph_sleep_time;
+extern unsigned int fgraph_no_sleep_time;
+extern bool fprofile_no_sleep_time;
 
 static inline bool
 ftrace_graph_ignore_func(struct fgraph_ops *gops, struct ftrace_graph_ent 
*trace)
diff --git a/kernel/trace/trace_functions_graph.c 
b/kernel/trace/trace_functions_graph.c
index 53adbe4bfedb..12315eb65925 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -19,6 +19,9 @@
 /* When set, irq functions might be ignored */
 static int ftrace_graph_skip_irqs;
 
+/* Do not record function time when task is sleeping */
+unsigned int fgraph_no_sleep_time;
+
 struct fgraph_cpu_data {
        pid_t           last_pid;
        int             depth;
@@ -239,13 +242,14 @@ static int graph_entry(struct ftrace_graph_ent *trace,
        if (ftrace_graph_ignore_irqs(tr))
                return 0;
 
-       if (fgraph_sleep_time) {
-               /* Only need to record the calltime */
-               ftimes = fgraph_reserve_data(gops->idx, 
sizeof(ftimes->calltime));
-       } else {
+       if (fgraph_no_sleep_time &&
+           !tracer_flags_is_set(tr, TRACE_GRAPH_SLEEP_TIME)) {
                ftimes = fgraph_reserve_data(gops->idx, sizeof(*ftimes));
                if (ftimes)
                        ftimes->sleeptime = current->ftrace_sleeptime;
+       } else {
+               /* Only need to record the calltime */
+               ftimes = fgraph_reserve_data(gops->idx, 
sizeof(ftimes->calltime));
        }
        if (!ftimes)
                return 0;
@@ -331,11 +335,15 @@ void __trace_graph_return(struct trace_array *tr,
        trace_buffer_unlock_commit_nostack(buffer, event);
 }
 
-static void handle_nosleeptime(struct ftrace_graph_ret *trace,
+static void handle_nosleeptime(struct trace_array *tr,
+                              struct ftrace_graph_ret *trace,
                               struct fgraph_times *ftimes,
                               int size)
 {
-       if (fgraph_sleep_time || size < sizeof(*ftimes))
+       if (size < sizeof(*ftimes))
+               return;
+
+       if (!fgraph_no_sleep_time || tracer_flags_is_set(tr, 
TRACE_GRAPH_SLEEP_TIME))
                return;
 
        ftimes->calltime += current->ftrace_sleeptime - ftimes->sleeptime;
@@ -364,7 +372,7 @@ void trace_graph_return(struct ftrace_graph_ret *trace,
        if (!ftimes)
                return;
 
-       handle_nosleeptime(trace, ftimes, size);
+       handle_nosleeptime(tr, trace, ftimes, size);
 
        calltime = ftimes->calltime;
 
@@ -377,6 +385,7 @@ static void trace_graph_thresh_return(struct 
ftrace_graph_ret *trace,
                                      struct ftrace_regs *fregs)
 {
        struct fgraph_times *ftimes;
+       struct trace_array *tr;
        int size;
 
        ftrace_graph_addr_finish(gops, trace);
@@ -390,7 +399,8 @@ static void trace_graph_thresh_return(struct 
ftrace_graph_ret *trace,
        if (!ftimes)
                return;
 
-       handle_nosleeptime(trace, ftimes, size);
+       tr = gops->private;
+       handle_nosleeptime(tr, trace, ftimes, size);
 
        if (tracing_thresh &&
            (trace_clock_local() - ftimes->calltime < tracing_thresh))
@@ -452,6 +462,9 @@ static int graph_trace_init(struct trace_array *tr)
        if (!tracer_flags_is_set(tr, TRACE_GRAPH_PRINT_IRQS))
                ftrace_graph_skip_irqs++;
 
+       if (!tracer_flags_is_set(tr, TRACE_GRAPH_SLEEP_TIME))
+               fgraph_no_sleep_time++;
+
        /* Make gops functions visible before we start tracing */
        smp_mb();
 
@@ -494,6 +507,11 @@ static void graph_trace_reset(struct trace_array *tr)
        if (WARN_ON_ONCE(ftrace_graph_skip_irqs < 0))
                ftrace_graph_skip_irqs = 0;
 
+       if (!tracer_flags_is_set(tr, TRACE_GRAPH_SLEEP_TIME))
+               fgraph_no_sleep_time--;
+       if (WARN_ON_ONCE(fgraph_no_sleep_time < 0))
+               fgraph_no_sleep_time = 0;
+
        tracing_stop_cmdline_record();
        unregister_ftrace_graph(tr->gops);
 }
@@ -1619,8 +1637,24 @@ void graph_trace_close(struct trace_iterator *iter)
 static int
 func_graph_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
 {
-       if (bit == TRACE_GRAPH_SLEEP_TIME)
-               ftrace_graph_sleep_time_control(set);
+/*
+ * The function profiler gets updated even if function graph
+ * isn't the current tracer. Handle it separately.
+ */
+#ifdef CONFIG_FUNCTION_PROFILER
+       if (bit == TRACE_GRAPH_SLEEP_TIME && (tr->flags & 
TRACE_ARRAY_FL_GLOBAL) &&
+           !!set == fprofile_no_sleep_time) {
+               if (set) {
+                       fgraph_no_sleep_time--;
+                       if (WARN_ON_ONCE(fgraph_no_sleep_time < 0))
+                               fgraph_no_sleep_time = 0;
+                       fprofile_no_sleep_time = false;
+               } else {
+                       fgraph_no_sleep_time++;
+                       fprofile_no_sleep_time = true;
+               }
+       }
+#endif
 
        /* Do nothing if the current tracer is not this tracer */
        if (tr->current_trace != &graph_trace)
@@ -1630,6 +1664,16 @@ func_graph_set_flag(struct trace_array *tr, u32 
old_flags, u32 bit, int set)
        if (!!set == !!(tr->current_trace_flags->val & bit))
                return 0;
 
+       if (bit == TRACE_GRAPH_SLEEP_TIME) {
+               if (set) {
+                       fgraph_no_sleep_time--;
+                       if (WARN_ON_ONCE(fgraph_no_sleep_time < 0))
+                               fgraph_no_sleep_time = 0;
+               } else {
+                       fgraph_no_sleep_time++;
+               }
+       }
+
        if (bit == TRACE_GRAPH_PRINT_IRQS) {
                if (set)
                        ftrace_graph_skip_irqs--;
-- 
2.51.0



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