From a9d61173dc1cb63e660ae89e874e51ba4fd2f991 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Fri, 24 Sep 2010 17:41:02 +0200 Subject: tracing: Add proper check for irq_depth routines The check_irq_entry and check_irq_return could be called from graph event context. In such case there's no graph private data allocated. Adding checks to handle this case. Signed-off-by: Jiri Olsa LKML-Reference: <20100924154102.GB1818@jolsa.brq.redhat.com> [ Fixed some grammar in the comments ] Signed-off-by: Steven Rostedt --- kernel/trace/trace_functions_graph.c | 24 ++++++++++++++++++++---- 1 file changed, 20 insertions(+), 4 deletions(-) (limited to 'kernel/trace/trace_functions_graph.c') diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index ef49e9370b2..4c58ccc6427 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -888,12 +888,20 @@ 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; - int *depth_irq = &(per_cpu_ptr(data->cpu_data, cpu)->depth_irq); - if (flags & TRACE_GRAPH_PRINT_IRQS) + /* + * 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 */ @@ -926,12 +934,20 @@ static int check_irq_return(struct trace_iterator *iter, u32 flags, int depth) { int cpu = iter->cpu; + int *depth_irq; struct fgraph_data *data = iter->private; - int *depth_irq = &(per_cpu_ptr(data->cpu_data, cpu)->depth_irq); - if (flags & TRACE_GRAPH_PRINT_IRQS) + /* + * 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 not inside the irq code. */ -- cgit v1.2.3-70-g09d2 From 0a772620a2e21fb55a02f70fe38d4b5c3a5fbbbf Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Thu, 23 Sep 2010 14:00:52 +0200 Subject: tracing: Make graph related irqs/preemptsoff functions global Move trace_graph_function() and print_graph_headers_flags() functions to the trace_function_graph.c to be globaly available. Signed-off-by: Jiri Olsa LKML-Reference: <1285243253-7372-3-git-send-email-jolsa@redhat.com> Signed-off-by: Steven Rostedt --- kernel/trace/trace.h | 4 +++ kernel/trace/trace_functions_graph.c | 63 ++++++++++++++++++++++++++++++++++-- kernel/trace/trace_irqsoff.c | 56 ++++---------------------------- 3 files changed, 71 insertions(+), 52 deletions(-) (limited to 'kernel/trace/trace_functions_graph.c') diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index d39b3c5454a..9021f8c0c0c 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -343,6 +343,10 @@ void trace_function(struct trace_array *tr, unsigned long ip, unsigned long parent_ip, unsigned long flags, int pc); +void trace_graph_function(struct trace_array *tr, + unsigned long ip, + unsigned long parent_ip, + unsigned long flags, int pc); void trace_default_header(struct seq_file *m); void print_trace_header(struct seq_file *m, struct trace_iterator *iter); int trace_empty(struct trace_iterator *iter); diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index 4c58ccc6427..6f8fe28acba 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -262,6 +262,35 @@ 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, parent_ip, flags, pc); + __trace_graph_function(tr, ip, flags, pc); +} + void __trace_graph_return(struct trace_array *tr, struct ftrace_graph_ret *trace, unsigned long flags, @@ -1179,7 +1208,7 @@ print_graph_comment(struct trace_seq *s, struct trace_entry *ent, enum print_line_t -print_graph_function_flags(struct trace_iterator *iter, u32 flags) +__print_graph_function_flags(struct trace_iterator *iter, u32 flags) { struct ftrace_graph_ent_entry *field; struct fgraph_data *data = iter->private; @@ -1242,7 +1271,18 @@ print_graph_function_flags(struct trace_iterator *iter, u32 flags) static enum print_line_t print_graph_function(struct trace_iterator *iter) { - return print_graph_function_flags(iter, tracer_flags.val); + return __print_graph_function_flags(iter, tracer_flags.val); +} + +enum print_line_t print_graph_function_flags(struct trace_iterator *iter, + u32 flags) +{ + if (trace_flags & TRACE_ITER_LATENCY_FMT) + flags |= TRACE_GRAPH_PRINT_DURATION; + else + flags |= TRACE_GRAPH_PRINT_ABS_TIME; + + return __print_graph_function_flags(iter, flags); } static enum print_line_t @@ -1274,7 +1314,7 @@ static void print_lat_header(struct seq_file *s, u32 flags) seq_printf(s, "#%.*s|||| / \n", size, spaces); } -void print_graph_headers_flags(struct seq_file *s, u32 flags) +static void __print_graph_headers_flags(struct seq_file *s, u32 flags) { int lat = trace_flags & TRACE_ITER_LATENCY_FMT; @@ -1315,6 +1355,23 @@ void print_graph_headers(struct seq_file *s) print_graph_headers_flags(s, tracer_flags.val); } +void print_graph_headers_flags(struct seq_file *s, u32 flags) +{ + struct trace_iterator *iter = s->private; + + if (trace_flags & TRACE_ITER_LATENCY_FMT) { + /* print nothing if the buffers are empty */ + if (trace_empty(iter)) + return; + + print_trace_header(s, iter); + flags |= TRACE_GRAPH_PRINT_DURATION; + } else + flags |= TRACE_GRAPH_PRINT_ABS_TIME; + + __print_graph_headers_flags(s, flags); +} + void graph_trace_open(struct trace_iterator *iter) { /* pid and depth on the last trace processed */ diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c index 73a6b0601f2..4047e98afcb 100644 --- a/kernel/trace/trace_irqsoff.c +++ b/kernel/trace/trace_irqsoff.c @@ -229,75 +229,33 @@ static void irqsoff_trace_close(struct trace_iterator *iter) static enum print_line_t irqsoff_print_line(struct trace_iterator *iter) { - u32 flags = GRAPH_TRACER_FLAGS; - - if (trace_flags & TRACE_ITER_LATENCY_FMT) - flags |= TRACE_GRAPH_PRINT_DURATION; - else - flags |= TRACE_GRAPH_PRINT_ABS_TIME; - /* * In graph mode call the graph tracer output function, * otherwise go with the TRACE_FN event handler */ if (is_graph()) - return print_graph_function_flags(iter, flags); + return print_graph_function_flags(iter, GRAPH_TRACER_FLAGS); return TRACE_TYPE_UNHANDLED; } static void irqsoff_print_header(struct seq_file *s) { - if (is_graph()) { - struct trace_iterator *iter = s->private; - u32 flags = GRAPH_TRACER_FLAGS; - - if (trace_flags & TRACE_ITER_LATENCY_FMT) { - /* print nothing if the buffers are empty */ - if (trace_empty(iter)) - return; - - print_trace_header(s, iter); - flags |= TRACE_GRAPH_PRINT_DURATION; - } else - flags |= TRACE_GRAPH_PRINT_ABS_TIME; - - print_graph_headers_flags(s, flags); - } else + if (is_graph()) + print_graph_headers_flags(s, GRAPH_TRACER_FLAGS); + else trace_default_header(s); } -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); -} - static void __trace_function(struct trace_array *tr, unsigned long ip, unsigned long parent_ip, unsigned long flags, int pc) { - if (!is_graph()) + if (is_graph()) + trace_graph_function(tr, ip, parent_ip, flags, pc); + else trace_function(tr, ip, parent_ip, flags, pc); - else { - trace_graph_function(tr, parent_ip, flags, pc); - trace_graph_function(tr, ip, flags, pc); - } } #else -- cgit v1.2.3-70-g09d2 From 78c89ba121221d9224a5747803d7fffe51cd6e44 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Tue, 5 Oct 2010 23:22:19 -0400 Subject: tracing: Remove parent recording in latency tracer graph options Even though the parent is recorded with the normal function tracing of the latency tracers (irqsoff and wakeup), the function graph recording is bogus. This is due to the function graph messing with the return stack. The latency tracers pass in as the parent CALLER_ADDR0, which works fine for plain function tracing. But this causes bogus output with the graph tracer: 3) -0 | d.s3. 0.000 us | return_to_handler(); 3) -0 | d.s3. 0.000 us | _raw_spin_unlock_irqrestore(); 3) -0 | d.s3. 0.000 us | return_to_handler(); 3) -0 | d.s3. 0.000 us | trace_hardirqs_on(); The "return_to_handle()" call is the trampoline of the function graph tracer, and is meaningless in this context. Cc: Jiri Olsa Signed-off-by: Steven Rostedt --- kernel/trace/trace_functions_graph.c | 1 - 1 file changed, 1 deletion(-) (limited to 'kernel/trace/trace_functions_graph.c') diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index 6f8fe28acba..76b05980225 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -287,7 +287,6 @@ trace_graph_function(struct trace_array *tr, unsigned long ip, unsigned long parent_ip, unsigned long flags, int pc) { - __trace_graph_function(tr, parent_ip, flags, pc); __trace_graph_function(tr, ip, flags, pc); } -- cgit v1.2.3-70-g09d2