From a2a16d6a3156ef7309ca7328a20c35df9418e670 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Tue, 24 Mar 2009 23:17:58 -0400 Subject: function-graph: add option to calculate graph time or not graph time is the time that a function is executing another function. Thus if function A calls B, if graph-time is set, then the time for A includes B. This is the default behavior. But if graph-time is off, then the time spent executing B is subtracted from A. Signed-off-by: Steven Rostedt --- include/linux/ftrace.h | 3 +-- kernel/trace/ftrace.c | 21 ++++++++++++++++++++- kernel/trace/trace.c | 4 +++- kernel/trace/trace.h | 1 + kernel/trace/trace_functions_graph.c | 8 ++++---- 5 files changed, 29 insertions(+), 8 deletions(-) diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 015a3d22cf74..9e0a8d245e55 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -365,6 +365,7 @@ struct ftrace_ret_stack { unsigned long ret; unsigned long func; unsigned long long calltime; + unsigned long long subtime; }; /* @@ -376,8 +377,6 @@ extern void return_to_handler(void); extern int ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth); -extern void -ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret); /* * Sometimes we don't want to trace a function with the function diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index ed1fc5021d44..71e5faef12ab 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -604,6 +604,7 @@ static int profile_graph_entry(struct ftrace_graph_ent *trace) static void profile_graph_return(struct ftrace_graph_ret *trace) { struct ftrace_profile_stat *stat; + unsigned long long calltime; struct ftrace_profile *rec; unsigned long flags; @@ -612,9 +613,27 @@ static void profile_graph_return(struct ftrace_graph_ret *trace) if (!stat->hash) goto out; + calltime = trace->rettime - trace->calltime; + + if (!(trace_flags & TRACE_ITER_GRAPH_TIME)) { + int index; + + index = trace->depth; + + /* Append this call time to the parent time to subtract */ + if (index) + current->ret_stack[index - 1].subtime += calltime; + + if (current->ret_stack[index].subtime < calltime) + calltime -= current->ret_stack[index].subtime; + else + calltime = 0; + } + rec = ftrace_find_profiled_func(stat, trace->func); if (rec) - rec->time += trace->rettime - trace->calltime; + rec->time += calltime; + out: local_irq_restore(flags); } diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 821bf49771d4..5d1a16cae376 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -255,7 +255,8 @@ static DECLARE_WAIT_QUEUE_HEAD(trace_wait); /* trace_flags holds trace_options default values */ unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | - TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME; + TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | + TRACE_ITER_GRAPH_TIME; /** * trace_wake_up - wake up tasks waiting for trace input @@ -317,6 +318,7 @@ static const char *trace_options[] = { "latency-format", "global-clock", "sleep-time", + "graph-time", NULL }; diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index c66ca3b66050..e3429a8ab059 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -685,6 +685,7 @@ enum trace_iterator_flags { TRACE_ITER_LATENCY_FMT = 0x40000, TRACE_ITER_GLOBAL_CLK = 0x80000, TRACE_ITER_SLEEP_TIME = 0x100000, + TRACE_ITER_GRAPH_TIME = 0x200000, }; /* diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index 85bba0f018b0..10f6ad7d85f6 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -78,13 +78,14 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth) current->ret_stack[index].ret = ret; current->ret_stack[index].func = func; current->ret_stack[index].calltime = calltime; + current->ret_stack[index].subtime = 0; *depth = index; return 0; } /* Retrieve a function return address to the trace stack on thread info.*/ -void +static void ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret) { int index; @@ -104,9 +105,6 @@ ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret) trace->calltime = current->ret_stack[index].calltime; trace->overrun = atomic_read(¤t->trace_overrun); trace->depth = index; - barrier(); - current->curr_ret_stack--; - } /* @@ -121,6 +119,8 @@ unsigned long ftrace_return_to_handler(void) ftrace_pop_return_trace(&trace, &ret); trace.rettime = trace_clock_local(); ftrace_graph_return(&trace); + barrier(); + current->curr_ret_stack--; if (unlikely(!ret)) { ftrace_graph_stop(); -- cgit v1.2.1