1 files changed, 201 insertions, 8 deletions

diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 6f233698518..76b05980225 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -15,15 +15,19 @@
 #include "trace.h"
 #include "trace_output.h"
 
+/* When set, irq functions will be ignored */
+static int ftrace_graph_skip_irqs;
+
 struct fgraph_cpu_data {
         pid_t           last_pid;
         int             depth;
+        int             depth_irq;
         int             ignore;
         unsigned long   enter_funcs[FTRACE_RETFUNC_DEPTH];
 };
 
 struct fgraph_data {
-        struct fgraph_cpu_data          *cpu_data;
+        struct fgraph_cpu_data __percpu *cpu_data;
 
         /* Place to preserve last processed entry. */
         struct ftrace_graph_ent_entry   ent;
@@ -41,6 +45,7 @@ struct fgraph_data {
 #define TRACE_GRAPH_PRINT_PROC          0x8
 #define TRACE_GRAPH_PRINT_DURATION      0x10
 #define TRACE_GRAPH_PRINT_ABS_TIME      0x20
+#define TRACE_GRAPH_PRINT_IRQS          0x40
 
 static struct tracer_opt trace_opts[] = {
         /* Display overruns? (for self-debug purpose) */
@@ -55,13 +60,15 @@ static struct tracer_opt trace_opts[] = {
         { TRACER_OPT(funcgraph-duration, TRACE_GRAPH_PRINT_DURATION) },
         /* Display absolute time of an entry */
         { TRACER_OPT(funcgraph-abstime, TRACE_GRAPH_PRINT_ABS_TIME) },
+        /* Display interrupts */
+        { TRACER_OPT(funcgraph-irqs, TRACE_GRAPH_PRINT_IRQS) },
         { } /* Empty entry */
 };
 
 static struct tracer_flags tracer_flags = {
         /* Don't display overruns and proc by default */
         .val = TRACE_GRAPH_PRINT_CPU | TRACE_GRAPH_PRINT_OVERHEAD |
-               TRACE_GRAPH_PRINT_DURATION,
+               TRACE_GRAPH_PRINT_DURATION | TRACE_GRAPH_PRINT_IRQS,
         .opts = trace_opts
 };
 
@@ -204,6 +211,14 @@ int __trace_graph_entry(struct trace_array *tr,
         return 1;
 }
 
+static inline int ftrace_graph_ignore_irqs(void)
+{
+        if (!ftrace_graph_skip_irqs)
+                return 0;
+
+        return in_irq();
+}
+
 int trace_graph_entry(struct ftrace_graph_ent *trace)
 {
         struct trace_array *tr = graph_array;
@@ -218,7 +233,8 @@ int trace_graph_entry(struct ftrace_graph_ent *trace)
                 return 0;
 
         /* trace it when it is-nested-in or is a function enabled. */
-        if (!(trace->depth || ftrace_graph_addr(trace->func)))
+        if (!(trace->depth || ftrace_graph_addr(trace->func)) ||
+              ftrace_graph_ignore_irqs())
                 return 0;
 
         local_irq_save(flags);
@@ -246,6 +262,34 @@ int trace_graph_thresh_entry(struct ftrace_graph_ent *trace)
                 return trace_graph_entry(trace);
 }
 
+static void
+__trace_graph_function(struct trace_array *tr,
+                unsigned long ip, unsigned long flags, int pc)
+{
+        u64 time = trace_clock_local();
+        struct ftrace_graph_ent ent = {
+                .func  = ip,
+                .depth = 0,
+        };
+        struct ftrace_graph_ret ret = {
+                .func     = ip,
+                .depth    = 0,
+                .calltime = time,
+                .rettime  = time,
+        };
+
+        __trace_graph_entry(tr, &ent, flags, pc);
+        __trace_graph_return(tr, &ret, flags, pc);
+}
+
+void
+trace_graph_function(struct trace_array *tr,
+                unsigned long ip, unsigned long parent_ip,
+                unsigned long flags, int pc)
+{
+        __trace_graph_function(tr, ip, flags, pc);
+}
+
 void __trace_graph_return(struct trace_array *tr,
                                 struct ftrace_graph_ret *trace,
                                 unsigned long flags,
@@ -649,8 +693,9 @@ trace_print_graph_duration(unsigned long long duration, struct trace_seq *s)
 
         /* Print nsecs (we don't want to exceed 7 numbers) */
         if (len < 7) {
-                snprintf(nsecs_str, min(sizeof(nsecs_str), 8UL - len), "%03lu",
-                         nsecs_rem);
+                size_t slen = min_t(size_t, sizeof(nsecs_str), 8UL - len);
+
+                snprintf(nsecs_str, slen, "%03lu", nsecs_rem);
                 ret = trace_seq_printf(s, ".%s", nsecs_str);
                 if (!ret)
                         return TRACE_TYPE_PARTIAL_LINE;
@@ -855,6 +900,108 @@ print_graph_prologue(struct trace_iterator *iter, struct trace_seq *s,
         return 0;
 }
 
+/*
+ * Entry check for irq code
+ *
+ * returns 1 if
+ *  - we are inside irq code
+ *  - we just extered irq code
+ *
+ * retunns 0 if
+ *  - funcgraph-interrupts option is set
+ *  - we are not inside irq code
+ */
+static int
+check_irq_entry(struct trace_iterator *iter, u32 flags,
+                unsigned long addr, int depth)
+{
+        int cpu = iter->cpu;
+        int *depth_irq;
+        struct fgraph_data *data = iter->private;
+
+        /*
+         * If we are either displaying irqs, or we got called as
+         * a graph event and private data does not exist,
+         * then we bypass the irq check.
+         */
+        if ((flags & TRACE_GRAPH_PRINT_IRQS) ||
+            (!data))
+                return 0;
+
+        depth_irq = &(per_cpu_ptr(data->cpu_data, cpu)->depth_irq);
+
+        /*
+         * We are inside the irq code
+         */
+        if (*depth_irq >= 0)
+                return 1;
+
+        if ((addr < (unsigned long)__irqentry_text_start) ||
+            (addr >= (unsigned long)__irqentry_text_end))
+                return 0;
+
+        /*
+         * We are entering irq code.
+         */
+        *depth_irq = depth;
+        return 1;
+}
+
+/*
+ * Return check for irq code
+ *
+ * returns 1 if
+ *  - we are inside irq code
+ *  - we just left irq code
+ *
+ * returns 0 if
+ *  - funcgraph-interrupts option is set
+ *  - we are not inside irq code