![Linus Torvalds](/assets/img/avatar_default.png)
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (34 commits) m68k: rename global variable vmalloc_end to m68k_vmalloc_end percpu: add missing per_cpu_ptr_to_phys() definition for UP percpu: Fix kdump failure if booted with percpu_alloc=page percpu: make misc percpu symbols unique percpu: make percpu symbols in ia64 unique percpu: make percpu symbols in powerpc unique percpu: make percpu symbols in x86 unique percpu: make percpu symbols in xen unique percpu: make percpu symbols in cpufreq unique percpu: make percpu symbols in oprofile unique percpu: make percpu symbols in tracer unique percpu: make percpu symbols under kernel/ and mm/ unique percpu: remove some sparse warnings percpu: make alloc_percpu() handle array types vmalloc: fix use of non-existent percpu variable in put_cpu_var() this_cpu: Use this_cpu_xx in trace_functions_graph.c this_cpu: Use this_cpu_xx for ftrace this_cpu: Use this_cpu_xx in nmi handling this_cpu: Use this_cpu operations in RCU this_cpu: Use this_cpu ops for VM statistics ... Fix up trivial (famous last words) global per-cpu naming conflicts in arch/x86/kvm/svm.c mm/slab.c
1174 lines
28 KiB
C
1174 lines
28 KiB
C
/*
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*
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* Function graph tracer.
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* Copyright (c) 2008-2009 Frederic Weisbecker <fweisbec@gmail.com>
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* Mostly borrowed from function tracer which
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* is Copyright (c) Steven Rostedt <srostedt@redhat.com>
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*
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*/
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#include <linux/debugfs.h>
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#include <linux/uaccess.h>
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#include <linux/ftrace.h>
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#include <linux/fs.h>
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#include "trace.h"
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#include "trace_output.h"
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struct fgraph_cpu_data {
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pid_t last_pid;
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int depth;
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int ignore;
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};
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struct fgraph_data {
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struct fgraph_cpu_data *cpu_data;
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/* Place to preserve last processed entry. */
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struct ftrace_graph_ent_entry ent;
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struct ftrace_graph_ret_entry ret;
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int failed;
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int cpu;
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};
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#define TRACE_GRAPH_INDENT 2
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/* Flag options */
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#define TRACE_GRAPH_PRINT_OVERRUN 0x1
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#define TRACE_GRAPH_PRINT_CPU 0x2
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#define TRACE_GRAPH_PRINT_OVERHEAD 0x4
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#define TRACE_GRAPH_PRINT_PROC 0x8
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#define TRACE_GRAPH_PRINT_DURATION 0x10
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#define TRACE_GRAPH_PRINT_ABS_TIME 0X20
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static struct tracer_opt trace_opts[] = {
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/* Display overruns? (for self-debug purpose) */
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{ TRACER_OPT(funcgraph-overrun, TRACE_GRAPH_PRINT_OVERRUN) },
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/* Display CPU ? */
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{ TRACER_OPT(funcgraph-cpu, TRACE_GRAPH_PRINT_CPU) },
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/* Display Overhead ? */
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{ TRACER_OPT(funcgraph-overhead, TRACE_GRAPH_PRINT_OVERHEAD) },
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/* Display proc name/pid */
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{ TRACER_OPT(funcgraph-proc, TRACE_GRAPH_PRINT_PROC) },
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/* Display duration of execution */
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{ TRACER_OPT(funcgraph-duration, TRACE_GRAPH_PRINT_DURATION) },
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/* Display absolute time of an entry */
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{ TRACER_OPT(funcgraph-abstime, TRACE_GRAPH_PRINT_ABS_TIME) },
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{ } /* Empty entry */
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};
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static struct tracer_flags tracer_flags = {
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/* Don't display overruns and proc by default */
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.val = TRACE_GRAPH_PRINT_CPU | TRACE_GRAPH_PRINT_OVERHEAD |
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TRACE_GRAPH_PRINT_DURATION,
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.opts = trace_opts
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};
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static struct trace_array *graph_array;
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/* Add a function return address to the trace stack on thread info.*/
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int
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ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
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unsigned long frame_pointer)
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{
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unsigned long long calltime;
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int index;
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if (!current->ret_stack)
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return -EBUSY;
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/*
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* We must make sure the ret_stack is tested before we read
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* anything else.
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*/
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smp_rmb();
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/* The return trace stack is full */
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if (current->curr_ret_stack == FTRACE_RETFUNC_DEPTH - 1) {
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atomic_inc(¤t->trace_overrun);
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return -EBUSY;
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}
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calltime = trace_clock_local();
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index = ++current->curr_ret_stack;
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barrier();
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current->ret_stack[index].ret = ret;
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current->ret_stack[index].func = func;
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current->ret_stack[index].calltime = calltime;
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current->ret_stack[index].subtime = 0;
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current->ret_stack[index].fp = frame_pointer;
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*depth = index;
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return 0;
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}
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/* Retrieve a function return address to the trace stack on thread info.*/
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static void
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ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret,
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unsigned long frame_pointer)
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{
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int index;
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index = current->curr_ret_stack;
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if (unlikely(index < 0)) {
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ftrace_graph_stop();
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WARN_ON(1);
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/* Might as well panic, otherwise we have no where to go */
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*ret = (unsigned long)panic;
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return;
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}
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#ifdef CONFIG_HAVE_FUNCTION_GRAPH_FP_TEST
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/*
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* The arch may choose to record the frame pointer used
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* and check it here to make sure that it is what we expect it
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* to be. If gcc does not set the place holder of the return
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* address in the frame pointer, and does a copy instead, then
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* the function graph trace will fail. This test detects this
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* case.
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*
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* Currently, x86_32 with optimize for size (-Os) makes the latest
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* gcc do the above.
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*/
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if (unlikely(current->ret_stack[index].fp != frame_pointer)) {
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ftrace_graph_stop();
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WARN(1, "Bad frame pointer: expected %lx, received %lx\n"
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" from func %ps return to %lx\n",
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current->ret_stack[index].fp,
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frame_pointer,
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(void *)current->ret_stack[index].func,
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current->ret_stack[index].ret);
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*ret = (unsigned long)panic;
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return;
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}
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#endif
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*ret = current->ret_stack[index].ret;
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trace->func = current->ret_stack[index].func;
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trace->calltime = current->ret_stack[index].calltime;
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trace->overrun = atomic_read(¤t->trace_overrun);
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trace->depth = index;
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}
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/*
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* Send the trace to the ring-buffer.
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* @return the original return address.
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*/
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unsigned long ftrace_return_to_handler(unsigned long frame_pointer)
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{
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struct ftrace_graph_ret trace;
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unsigned long ret;
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ftrace_pop_return_trace(&trace, &ret, frame_pointer);
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trace.rettime = trace_clock_local();
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ftrace_graph_return(&trace);
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barrier();
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current->curr_ret_stack--;
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if (unlikely(!ret)) {
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ftrace_graph_stop();
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WARN_ON(1);
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/* Might as well panic. What else to do? */
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ret = (unsigned long)panic;
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}
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return ret;
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}
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static int __trace_graph_entry(struct trace_array *tr,
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struct ftrace_graph_ent *trace,
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unsigned long flags,
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int pc)
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{
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struct ftrace_event_call *call = &event_funcgraph_entry;
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struct ring_buffer_event *event;
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struct ring_buffer *buffer = tr->buffer;
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struct ftrace_graph_ent_entry *entry;
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if (unlikely(__this_cpu_read(per_cpu_var(ftrace_cpu_disabled))))
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return 0;
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event = trace_buffer_lock_reserve(buffer, TRACE_GRAPH_ENT,
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sizeof(*entry), flags, pc);
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if (!event)
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return 0;
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entry = ring_buffer_event_data(event);
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entry->graph_ent = *trace;
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if (!filter_current_check_discard(buffer, call, entry, event))
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ring_buffer_unlock_commit(buffer, event);
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return 1;
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}
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int trace_graph_entry(struct ftrace_graph_ent *trace)
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{
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struct trace_array *tr = graph_array;
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struct trace_array_cpu *data;
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unsigned long flags;
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long disabled;
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int ret;
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int cpu;
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int pc;
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if (unlikely(!tr))
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return 0;
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if (!ftrace_trace_task(current))
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return 0;
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if (!ftrace_graph_addr(trace->func))
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return 0;
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local_irq_save(flags);
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cpu = raw_smp_processor_id();
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data = tr->data[cpu];
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disabled = atomic_inc_return(&data->disabled);
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if (likely(disabled == 1)) {
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pc = preempt_count();
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ret = __trace_graph_entry(tr, trace, flags, pc);
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} else {
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ret = 0;
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}
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/* Only do the atomic if it is not already set */
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if (!test_tsk_trace_graph(current))
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set_tsk_trace_graph(current);
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atomic_dec(&data->disabled);
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local_irq_restore(flags);
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return ret;
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}
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static void __trace_graph_return(struct trace_array *tr,
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struct ftrace_graph_ret *trace,
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unsigned long flags,
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int pc)
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{
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struct ftrace_event_call *call = &event_funcgraph_exit;
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struct ring_buffer_event *event;
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struct ring_buffer *buffer = tr->buffer;
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struct ftrace_graph_ret_entry *entry;
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if (unlikely(__this_cpu_read(per_cpu_var(ftrace_cpu_disabled))))
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return;
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event = trace_buffer_lock_reserve(buffer, TRACE_GRAPH_RET,
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sizeof(*entry), flags, pc);
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if (!event)
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return;
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entry = ring_buffer_event_data(event);
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entry->ret = *trace;
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if (!filter_current_check_discard(buffer, call, entry, event))
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ring_buffer_unlock_commit(buffer, event);
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}
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void trace_graph_return(struct ftrace_graph_ret *trace)
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{
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struct trace_array *tr = graph_array;
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struct trace_array_cpu *data;
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unsigned long flags;
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long disabled;
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int cpu;
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int pc;
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local_irq_save(flags);
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cpu = raw_smp_processor_id();
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data = tr->data[cpu];
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disabled = atomic_inc_return(&data->disabled);
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if (likely(disabled == 1)) {
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pc = preempt_count();
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__trace_graph_return(tr, trace, flags, pc);
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}
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if (!trace->depth)
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clear_tsk_trace_graph(current);
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atomic_dec(&data->disabled);
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local_irq_restore(flags);
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}
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static int graph_trace_init(struct trace_array *tr)
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{
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int ret;
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graph_array = tr;
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ret = register_ftrace_graph(&trace_graph_return,
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&trace_graph_entry);
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if (ret)
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return ret;
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tracing_start_cmdline_record();
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return 0;
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}
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void set_graph_array(struct trace_array *tr)
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{
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graph_array = tr;
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}
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static void graph_trace_reset(struct trace_array *tr)
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{
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tracing_stop_cmdline_record();
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unregister_ftrace_graph();
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}
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static int max_bytes_for_cpu;
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static enum print_line_t
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print_graph_cpu(struct trace_seq *s, int cpu)
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{
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int ret;
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/*
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* Start with a space character - to make it stand out
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* to the right a bit when trace output is pasted into
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* email:
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*/
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ret = trace_seq_printf(s, " %*d) ", max_bytes_for_cpu, cpu);
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if (!ret)
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return TRACE_TYPE_PARTIAL_LINE;
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return TRACE_TYPE_HANDLED;
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}
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#define TRACE_GRAPH_PROCINFO_LENGTH 14
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static enum print_line_t
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print_graph_proc(struct trace_seq *s, pid_t pid)
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{
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char comm[TASK_COMM_LEN];
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/* sign + log10(MAX_INT) + '\0' */
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char pid_str[11];
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int spaces = 0;
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int ret;
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int len;
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int i;
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trace_find_cmdline(pid, comm);
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comm[7] = '\0';
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sprintf(pid_str, "%d", pid);
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/* 1 stands for the "-" character */
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len = strlen(comm) + strlen(pid_str) + 1;
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if (len < TRACE_GRAPH_PROCINFO_LENGTH)
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spaces = TRACE_GRAPH_PROCINFO_LENGTH - len;
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/* First spaces to align center */
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for (i = 0; i < spaces / 2; i++) {
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ret = trace_seq_printf(s, " ");
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if (!ret)
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return TRACE_TYPE_PARTIAL_LINE;
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}
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ret = trace_seq_printf(s, "%s-%s", comm, pid_str);
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if (!ret)
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return TRACE_TYPE_PARTIAL_LINE;
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/* Last spaces to align center */
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for (i = 0; i < spaces - (spaces / 2); i++) {
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ret = trace_seq_printf(s, " ");
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if (!ret)
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return TRACE_TYPE_PARTIAL_LINE;
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}
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return TRACE_TYPE_HANDLED;
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}
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static enum print_line_t
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print_graph_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
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{
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if (!trace_seq_putc(s, ' '))
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return 0;
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return trace_print_lat_fmt(s, entry);
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}
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/* If the pid changed since the last trace, output this event */
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static enum print_line_t
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verif_pid(struct trace_seq *s, pid_t pid, int cpu, struct fgraph_data *data)
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{
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pid_t prev_pid;
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pid_t *last_pid;
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int ret;
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if (!data)
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return TRACE_TYPE_HANDLED;
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last_pid = &(per_cpu_ptr(data->cpu_data, cpu)->last_pid);
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if (*last_pid == pid)
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return TRACE_TYPE_HANDLED;
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prev_pid = *last_pid;
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*last_pid = pid;
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if (prev_pid == -1)
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return TRACE_TYPE_HANDLED;
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/*
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* Context-switch trace line:
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------------------------------------------
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| 1) migration/0--1 => sshd-1755
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------------------------------------------
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*/
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ret = trace_seq_printf(s,
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" ------------------------------------------\n");
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if (!ret)
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return TRACE_TYPE_PARTIAL_LINE;
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ret = print_graph_cpu(s, cpu);
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if (ret == TRACE_TYPE_PARTIAL_LINE)
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return TRACE_TYPE_PARTIAL_LINE;
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ret = print_graph_proc(s, prev_pid);
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if (ret == TRACE_TYPE_PARTIAL_LINE)
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return TRACE_TYPE_PARTIAL_LINE;
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ret = trace_seq_printf(s, " => ");
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if (!ret)
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return TRACE_TYPE_PARTIAL_LINE;
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ret = print_graph_proc(s, pid);
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if (ret == TRACE_TYPE_PARTIAL_LINE)
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return TRACE_TYPE_PARTIAL_LINE;
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ret = trace_seq_printf(s,
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"\n ------------------------------------------\n\n");
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if (!ret)
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return TRACE_TYPE_PARTIAL_LINE;
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return TRACE_TYPE_HANDLED;
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}
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static struct ftrace_graph_ret_entry *
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get_return_for_leaf(struct trace_iterator *iter,
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struct ftrace_graph_ent_entry *curr)
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{
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struct fgraph_data *data = iter->private;
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struct ring_buffer_iter *ring_iter = NULL;
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struct ring_buffer_event *event;
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struct ftrace_graph_ret_entry *next;
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/*
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* If the previous output failed to write to the seq buffer,
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* then we just reuse the data from before.
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*/
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if (data && data->failed) {
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curr = &data->ent;
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next = &data->ret;
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} else {
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ring_iter = iter->buffer_iter[iter->cpu];
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/* First peek to compare current entry and the next one */
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if (ring_iter)
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event = ring_buffer_iter_peek(ring_iter, NULL);
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else {
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/*
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* We need to consume the current entry to see
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* the next one.
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*/
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ring_buffer_consume(iter->tr->buffer, iter->cpu, NULL);
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event = ring_buffer_peek(iter->tr->buffer, iter->cpu,
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NULL);
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}
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if (!event)
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return NULL;
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next = ring_buffer_event_data(event);
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if (data) {
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/*
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* Save current and next entries for later reference
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* if the output fails.
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*/
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data->ent = *curr;
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data->ret = *next;
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}
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}
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if (next->ent.type != TRACE_GRAPH_RET)
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return NULL;
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if (curr->ent.pid != next->ent.pid ||
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curr->graph_ent.func != next->ret.func)
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return NULL;
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/* this is a leaf, now advance the iterator */
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if (ring_iter)
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ring_buffer_read(ring_iter, NULL);
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return next;
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}
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/* Signal a overhead of time execution to the output */
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static int
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print_graph_overhead(unsigned long long duration, struct trace_seq *s)
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{
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/* If duration disappear, we don't need anything */
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if (!(tracer_flags.val & TRACE_GRAPH_PRINT_DURATION))
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return 1;
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/* Non nested entry or return */
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if (duration == -1)
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return trace_seq_printf(s, " ");
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if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERHEAD) {
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/* Duration exceeded 100 msecs */
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if (duration > 100000ULL)
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return trace_seq_printf(s, "! ");
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/* Duration exceeded 10 msecs */
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if (duration > 10000ULL)
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return trace_seq_printf(s, "+ ");
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}
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return trace_seq_printf(s, " ");
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}
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|
|
static int print_graph_abs_time(u64 t, struct trace_seq *s)
|
|
{
|
|
unsigned long usecs_rem;
|
|
|
|
usecs_rem = do_div(t, NSEC_PER_SEC);
|
|
usecs_rem /= 1000;
|
|
|
|
return trace_seq_printf(s, "%5lu.%06lu | ",
|
|
(unsigned long)t, usecs_rem);
|
|
}
|
|
|
|
static enum print_line_t
|
|
print_graph_irq(struct trace_iterator *iter, unsigned long addr,
|
|
enum trace_type type, int cpu, pid_t pid)
|
|
{
|
|
int ret;
|
|
struct trace_seq *s = &iter->seq;
|
|
|
|
if (addr < (unsigned long)__irqentry_text_start ||
|
|
addr >= (unsigned long)__irqentry_text_end)
|
|
return TRACE_TYPE_UNHANDLED;
|
|
|
|
/* Absolute time */
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME) {
|
|
ret = print_graph_abs_time(iter->ts, s);
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
|
|
/* Cpu */
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU) {
|
|
ret = print_graph_cpu(s, cpu);
|
|
if (ret == TRACE_TYPE_PARTIAL_LINE)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
|
|
/* Proc */
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) {
|
|
ret = print_graph_proc(s, pid);
|
|
if (ret == TRACE_TYPE_PARTIAL_LINE)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
ret = trace_seq_printf(s, " | ");
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
|
|
/* No overhead */
|
|
ret = print_graph_overhead(-1, s);
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
if (type == TRACE_GRAPH_ENT)
|
|
ret = trace_seq_printf(s, "==========>");
|
|
else
|
|
ret = trace_seq_printf(s, "<==========");
|
|
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
/* Don't close the duration column if haven't one */
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION)
|
|
trace_seq_printf(s, " |");
|
|
ret = trace_seq_printf(s, "\n");
|
|
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
return TRACE_TYPE_HANDLED;
|
|
}
|
|
|
|
enum print_line_t
|
|
trace_print_graph_duration(unsigned long long duration, struct trace_seq *s)
|
|
{
|
|
unsigned long nsecs_rem = do_div(duration, 1000);
|
|
/* log10(ULONG_MAX) + '\0' */
|
|
char msecs_str[21];
|
|
char nsecs_str[5];
|
|
int ret, len;
|
|
int i;
|
|
|
|
sprintf(msecs_str, "%lu", (unsigned long) duration);
|
|
|
|
/* Print msecs */
|
|
ret = trace_seq_printf(s, "%s", msecs_str);
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
len = strlen(msecs_str);
|
|
|
|
/* Print nsecs (we don't want to exceed 7 numbers) */
|
|
if (len < 7) {
|
|
snprintf(nsecs_str, 8 - len, "%03lu", nsecs_rem);
|
|
ret = trace_seq_printf(s, ".%s", nsecs_str);
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
len += strlen(nsecs_str);
|
|
}
|
|
|
|
ret = trace_seq_printf(s, " us ");
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
/* Print remaining spaces to fit the row's width */
|
|
for (i = len; i < 7; i++) {
|
|
ret = trace_seq_printf(s, " ");
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
return TRACE_TYPE_HANDLED;
|
|
}
|
|
|
|
static enum print_line_t
|
|
print_graph_duration(unsigned long long duration, struct trace_seq *s)
|
|
{
|
|
int ret;
|
|
|
|
ret = trace_print_graph_duration(duration, s);
|
|
if (ret != TRACE_TYPE_HANDLED)
|
|
return ret;
|
|
|
|
ret = trace_seq_printf(s, "| ");
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
return TRACE_TYPE_HANDLED;
|
|
}
|
|
|
|
/* Case of a leaf function on its call entry */
|
|
static enum print_line_t
|
|
print_graph_entry_leaf(struct trace_iterator *iter,
|
|
struct ftrace_graph_ent_entry *entry,
|
|
struct ftrace_graph_ret_entry *ret_entry, struct trace_seq *s)
|
|
{
|
|
struct fgraph_data *data = iter->private;
|
|
struct ftrace_graph_ret *graph_ret;
|
|
struct ftrace_graph_ent *call;
|
|
unsigned long long duration;
|
|
int ret;
|
|
int i;
|
|
|
|
graph_ret = &ret_entry->ret;
|
|
call = &entry->graph_ent;
|
|
duration = graph_ret->rettime - graph_ret->calltime;
|
|
|
|
if (data) {
|
|
int cpu = iter->cpu;
|
|
int *depth = &(per_cpu_ptr(data->cpu_data, cpu)->depth);
|
|
|
|
/*
|
|
* Comments display at + 1 to depth. Since
|
|
* this is a leaf function, keep the comments
|
|
* equal to this depth.
|
|
*/
|
|
*depth = call->depth - 1;
|
|
}
|
|
|
|
/* Overhead */
|
|
ret = print_graph_overhead(duration, s);
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
/* Duration */
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION) {
|
|
ret = print_graph_duration(duration, s);
|
|
if (ret == TRACE_TYPE_PARTIAL_LINE)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
|
|
/* Function */
|
|
for (i = 0; i < call->depth * TRACE_GRAPH_INDENT; i++) {
|
|
ret = trace_seq_printf(s, " ");
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
|
|
ret = trace_seq_printf(s, "%ps();\n", (void *)call->func);
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
return TRACE_TYPE_HANDLED;
|
|
}
|
|
|
|
static enum print_line_t
|
|
print_graph_entry_nested(struct trace_iterator *iter,
|
|
struct ftrace_graph_ent_entry *entry,
|
|
struct trace_seq *s, int cpu)
|
|
{
|
|
struct ftrace_graph_ent *call = &entry->graph_ent;
|
|
struct fgraph_data *data = iter->private;
|
|
int ret;
|
|
int i;
|
|
|
|
if (data) {
|
|
int cpu = iter->cpu;
|
|
int *depth = &(per_cpu_ptr(data->cpu_data, cpu)->depth);
|
|
|
|
*depth = call->depth;
|
|
}
|
|
|
|
/* No overhead */
|
|
ret = print_graph_overhead(-1, s);
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
/* No time */
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION) {
|
|
ret = trace_seq_printf(s, " | ");
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
|
|
/* Function */
|
|
for (i = 0; i < call->depth * TRACE_GRAPH_INDENT; i++) {
|
|
ret = trace_seq_printf(s, " ");
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
|
|
ret = trace_seq_printf(s, "%ps() {\n", (void *)call->func);
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
/*
|
|
* we already consumed the current entry to check the next one
|
|
* and see if this is a leaf.
|
|
*/
|
|
return TRACE_TYPE_NO_CONSUME;
|
|
}
|
|
|
|
static enum print_line_t
|
|
print_graph_prologue(struct trace_iterator *iter, struct trace_seq *s,
|
|
int type, unsigned long addr)
|
|
{
|
|
struct fgraph_data *data = iter->private;
|
|
struct trace_entry *ent = iter->ent;
|
|
int cpu = iter->cpu;
|
|
int ret;
|
|
|
|
/* Pid */
|
|
if (verif_pid(s, ent->pid, cpu, data) == TRACE_TYPE_PARTIAL_LINE)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
if (type) {
|
|
/* Interrupt */
|
|
ret = print_graph_irq(iter, addr, type, cpu, ent->pid);
|
|
if (ret == TRACE_TYPE_PARTIAL_LINE)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
|
|
/* Absolute time */
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME) {
|
|
ret = print_graph_abs_time(iter->ts, s);
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
|
|
/* Cpu */
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU) {
|
|
ret = print_graph_cpu(s, cpu);
|
|
if (ret == TRACE_TYPE_PARTIAL_LINE)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
|
|
/* Proc */
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) {
|
|
ret = print_graph_proc(s, ent->pid);
|
|
if (ret == TRACE_TYPE_PARTIAL_LINE)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
ret = trace_seq_printf(s, " | ");
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
|
|
/* Latency format */
|
|
if (trace_flags & TRACE_ITER_LATENCY_FMT) {
|
|
ret = print_graph_lat_fmt(s, ent);
|
|
if (ret == TRACE_TYPE_PARTIAL_LINE)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static enum print_line_t
|
|
print_graph_entry(struct ftrace_graph_ent_entry *field, struct trace_seq *s,
|
|
struct trace_iterator *iter)
|
|
{
|
|
struct fgraph_data *data = iter->private;
|
|
struct ftrace_graph_ent *call = &field->graph_ent;
|
|
struct ftrace_graph_ret_entry *leaf_ret;
|
|
static enum print_line_t ret;
|
|
int cpu = iter->cpu;
|
|
|
|
if (print_graph_prologue(iter, s, TRACE_GRAPH_ENT, call->func))
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
leaf_ret = get_return_for_leaf(iter, field);
|
|
if (leaf_ret)
|
|
ret = print_graph_entry_leaf(iter, field, leaf_ret, s);
|
|
else
|
|
ret = print_graph_entry_nested(iter, field, s, cpu);
|
|
|
|
if (data) {
|
|
/*
|
|
* If we failed to write our output, then we need to make
|
|
* note of it. Because we already consumed our entry.
|
|
*/
|
|
if (s->full) {
|
|
data->failed = 1;
|
|
data->cpu = cpu;
|
|
} else
|
|
data->failed = 0;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static enum print_line_t
|
|
print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
|
|
struct trace_entry *ent, struct trace_iterator *iter)
|
|
{
|
|
unsigned long long duration = trace->rettime - trace->calltime;
|
|
struct fgraph_data *data = iter->private;
|
|
pid_t pid = ent->pid;
|
|
int cpu = iter->cpu;
|
|
int ret;
|
|
int i;
|
|
|
|
if (data) {
|
|
int cpu = iter->cpu;
|
|
int *depth = &(per_cpu_ptr(data->cpu_data, cpu)->depth);
|
|
|
|
/*
|
|
* Comments display at + 1 to depth. This is the
|
|
* return from a function, we now want the comments
|
|
* to display at the same level of the bracket.
|
|
*/
|
|
*depth = trace->depth - 1;
|
|
}
|
|
|
|
if (print_graph_prologue(iter, s, 0, 0))
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
/* Overhead */
|
|
ret = print_graph_overhead(duration, s);
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
/* Duration */
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION) {
|
|
ret = print_graph_duration(duration, s);
|
|
if (ret == TRACE_TYPE_PARTIAL_LINE)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
|
|
/* Closing brace */
|
|
for (i = 0; i < trace->depth * TRACE_GRAPH_INDENT; i++) {
|
|
ret = trace_seq_printf(s, " ");
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
|
|
ret = trace_seq_printf(s, "}\n");
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
/* Overrun */
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERRUN) {
|
|
ret = trace_seq_printf(s, " (Overruns: %lu)\n",
|
|
trace->overrun);
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
|
|
ret = print_graph_irq(iter, trace->func, TRACE_GRAPH_RET, cpu, pid);
|
|
if (ret == TRACE_TYPE_PARTIAL_LINE)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
return TRACE_TYPE_HANDLED;
|
|
}
|
|
|
|
static enum print_line_t
|
|
print_graph_comment(struct trace_seq *s, struct trace_entry *ent,
|
|
struct trace_iterator *iter)
|
|
{
|
|
unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK);
|
|
struct fgraph_data *data = iter->private;
|
|
struct trace_event *event;
|
|
int depth = 0;
|
|
int ret;
|
|
int i;
|
|
|
|
if (data)
|
|
depth = per_cpu_ptr(data->cpu_data, iter->cpu)->depth;
|
|
|
|
if (print_graph_prologue(iter, s, 0, 0))
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
/* No overhead */
|
|
ret = print_graph_overhead(-1, s);
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
/* No time */
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION) {
|
|
ret = trace_seq_printf(s, " | ");
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
|
|
/* Indentation */
|
|
if (depth > 0)
|
|
for (i = 0; i < (depth + 1) * TRACE_GRAPH_INDENT; i++) {
|
|
ret = trace_seq_printf(s, " ");
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
}
|
|
|
|
/* The comment */
|
|
ret = trace_seq_printf(s, "/* ");
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
switch (iter->ent->type) {
|
|
case TRACE_BPRINT:
|
|
ret = trace_print_bprintk_msg_only(iter);
|
|
if (ret != TRACE_TYPE_HANDLED)
|
|
return ret;
|
|
break;
|
|
case TRACE_PRINT:
|
|
ret = trace_print_printk_msg_only(iter);
|
|
if (ret != TRACE_TYPE_HANDLED)
|
|
return ret;
|
|
break;
|
|
default:
|
|
event = ftrace_find_event(ent->type);
|
|
if (!event)
|
|
return TRACE_TYPE_UNHANDLED;
|
|
|
|
ret = event->trace(iter, sym_flags);
|
|
if (ret != TRACE_TYPE_HANDLED)
|
|
return ret;
|
|
}
|
|
|
|
/* Strip ending newline */
|
|
if (s->buffer[s->len - 1] == '\n') {
|
|
s->buffer[s->len - 1] = '\0';
|
|
s->len--;
|
|
}
|
|
|
|
ret = trace_seq_printf(s, " */\n");
|
|
if (!ret)
|
|
return TRACE_TYPE_PARTIAL_LINE;
|
|
|
|
return TRACE_TYPE_HANDLED;
|
|
}
|
|
|
|
|
|
enum print_line_t
|
|
print_graph_function(struct trace_iterator *iter)
|
|
{
|
|
struct ftrace_graph_ent_entry *field;
|
|
struct fgraph_data *data = iter->private;
|
|
struct trace_entry *entry = iter->ent;
|
|
struct trace_seq *s = &iter->seq;
|
|
int cpu = iter->cpu;
|
|
int ret;
|
|
|
|
if (data && per_cpu_ptr(data->cpu_data, cpu)->ignore) {
|
|
per_cpu_ptr(data->cpu_data, cpu)->ignore = 0;
|
|
return TRACE_TYPE_HANDLED;
|
|
}
|
|
|
|
/*
|
|
* If the last output failed, there's a possibility we need
|
|
* to print out the missing entry which would never go out.
|
|
*/
|
|
if (data && data->failed) {
|
|
field = &data->ent;
|
|
iter->cpu = data->cpu;
|
|
ret = print_graph_entry(field, s, iter);
|
|
if (ret == TRACE_TYPE_HANDLED && iter->cpu != cpu) {
|
|
per_cpu_ptr(data->cpu_data, iter->cpu)->ignore = 1;
|
|
ret = TRACE_TYPE_NO_CONSUME;
|
|
}
|
|
iter->cpu = cpu;
|
|
return ret;
|
|
}
|
|
|
|
switch (entry->type) {
|
|
case TRACE_GRAPH_ENT: {
|
|
/*
|
|
* print_graph_entry() may consume the current event,
|
|
* thus @field may become invalid, so we need to save it.
|
|
* sizeof(struct ftrace_graph_ent_entry) is very small,
|
|
* it can be safely saved at the stack.
|
|
*/
|
|
struct ftrace_graph_ent_entry saved;
|
|
trace_assign_type(field, entry);
|
|
saved = *field;
|
|
return print_graph_entry(&saved, s, iter);
|
|
}
|
|
case TRACE_GRAPH_RET: {
|
|
struct ftrace_graph_ret_entry *field;
|
|
trace_assign_type(field, entry);
|
|
return print_graph_return(&field->ret, s, entry, iter);
|
|
}
|
|
default:
|
|
return print_graph_comment(s, entry, iter);
|
|
}
|
|
|
|
return TRACE_TYPE_HANDLED;
|
|
}
|
|
|
|
static void print_lat_header(struct seq_file *s)
|
|
{
|
|
static const char spaces[] = " " /* 16 spaces */
|
|
" " /* 4 spaces */
|
|
" "; /* 17 spaces */
|
|
int size = 0;
|
|
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME)
|
|
size += 16;
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU)
|
|
size += 4;
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC)
|
|
size += 17;
|
|
|
|
seq_printf(s, "#%.*s _-----=> irqs-off \n", size, spaces);
|
|
seq_printf(s, "#%.*s / _----=> need-resched \n", size, spaces);
|
|
seq_printf(s, "#%.*s| / _---=> hardirq/softirq \n", size, spaces);
|
|
seq_printf(s, "#%.*s|| / _--=> preempt-depth \n", size, spaces);
|
|
seq_printf(s, "#%.*s||| / _-=> lock-depth \n", size, spaces);
|
|
seq_printf(s, "#%.*s|||| / \n", size, spaces);
|
|
}
|
|
|
|
static void print_graph_headers(struct seq_file *s)
|
|
{
|
|
int lat = trace_flags & TRACE_ITER_LATENCY_FMT;
|
|
|
|
if (lat)
|
|
print_lat_header(s);
|
|
|
|
/* 1st line */
|
|
seq_printf(s, "#");
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME)
|
|
seq_printf(s, " TIME ");
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU)
|
|
seq_printf(s, " CPU");
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC)
|
|
seq_printf(s, " TASK/PID ");
|
|
if (lat)
|
|
seq_printf(s, "|||||");
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION)
|
|
seq_printf(s, " DURATION ");
|
|
seq_printf(s, " FUNCTION CALLS\n");
|
|
|
|
/* 2nd line */
|
|
seq_printf(s, "#");
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME)
|
|
seq_printf(s, " | ");
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU)
|
|
seq_printf(s, " | ");
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC)
|
|
seq_printf(s, " | | ");
|
|
if (lat)
|
|
seq_printf(s, "|||||");
|
|
if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION)
|
|
seq_printf(s, " | | ");
|
|
seq_printf(s, " | | | |\n");
|
|
}
|
|
|
|
static void graph_trace_open(struct trace_iterator *iter)
|
|
{
|
|
/* pid and depth on the last trace processed */
|
|
struct fgraph_data *data;
|
|
int cpu;
|
|
|
|
iter->private = NULL;
|
|
|
|
data = kzalloc(sizeof(*data), GFP_KERNEL);
|
|
if (!data)
|
|
goto out_err;
|
|
|
|
data->cpu_data = alloc_percpu(struct fgraph_cpu_data);
|
|
if (!data->cpu_data)
|
|
goto out_err_free;
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
pid_t *pid = &(per_cpu_ptr(data->cpu_data, cpu)->last_pid);
|
|
int *depth = &(per_cpu_ptr(data->cpu_data, cpu)->depth);
|
|
int *ignore = &(per_cpu_ptr(data->cpu_data, cpu)->ignore);
|
|
*pid = -1;
|
|
*depth = 0;
|
|
*ignore = 0;
|
|
}
|
|
|
|
iter->private = data;
|
|
|
|
return;
|
|
|
|
out_err_free:
|
|
kfree(data);
|
|
out_err:
|
|
pr_warning("function graph tracer: not enough memory\n");
|
|
}
|
|
|
|
static void graph_trace_close(struct trace_iterator *iter)
|
|
{
|
|
struct fgraph_data *data = iter->private;
|
|
|
|
if (data) {
|
|
free_percpu(data->cpu_data);
|
|
kfree(data);
|
|
}
|
|
}
|
|
|
|
static struct tracer graph_trace __read_mostly = {
|
|
.name = "function_graph",
|
|
.open = graph_trace_open,
|
|
.pipe_open = graph_trace_open,
|
|
.close = graph_trace_close,
|
|
.pipe_close = graph_trace_close,
|
|
.wait_pipe = poll_wait_pipe,
|
|
.init = graph_trace_init,
|
|
.reset = graph_trace_reset,
|
|
.print_line = print_graph_function,
|
|
.print_header = print_graph_headers,
|
|
.flags = &tracer_flags,
|
|
#ifdef CONFIG_FTRACE_SELFTEST
|
|
.selftest = trace_selftest_startup_function_graph,
|
|
#endif
|
|
};
|
|
|
|
static __init int init_graph_trace(void)
|
|
{
|
|
max_bytes_for_cpu = snprintf(NULL, 0, "%d", nr_cpu_ids - 1);
|
|
|
|
return register_tracer(&graph_trace);
|
|
}
|
|
|
|
device_initcall(init_graph_trace);
|