diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2009-02-19 12:14:22 -0500 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-02-19 12:14:22 -0500 |
commit | f54b2fe4aef9aa74ddf2c856928c3e29f3371fe7 (patch) | |
tree | 8ca38b4fab7d2a9a5bfd26a2e640631d52894fe6 | |
parent | 83ff1af9d330348d1a6685b0c06d33847cd72723 (diff) | |
parent | ed4a2f374d71770796789ed559c35a36bab82f1a (diff) |
Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
tracing: limit the number of loops the ring buffer self test can make
tracing: have function trace select kallsyms
tracing: disable tracing while testing ring buffer
tracing/function-graph-tracer: trace the idle tasks
-rw-r--r-- | kernel/trace/Kconfig | 2 | ||||
-rw-r--r-- | kernel/trace/ftrace.c | 6 | ||||
-rw-r--r-- | kernel/trace/trace_selftest.c | 19 |
3 files changed, 26 insertions, 1 deletions
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 58a93fbd68aa..34e707e5ab87 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig | |||
@@ -52,6 +52,7 @@ config FUNCTION_TRACER | |||
52 | depends on HAVE_FUNCTION_TRACER | 52 | depends on HAVE_FUNCTION_TRACER |
53 | depends on DEBUG_KERNEL | 53 | depends on DEBUG_KERNEL |
54 | select FRAME_POINTER | 54 | select FRAME_POINTER |
55 | select KALLSYMS | ||
55 | select TRACING | 56 | select TRACING |
56 | select CONTEXT_SWITCH_TRACER | 57 | select CONTEXT_SWITCH_TRACER |
57 | help | 58 | help |
@@ -238,6 +239,7 @@ config STACK_TRACER | |||
238 | depends on DEBUG_KERNEL | 239 | depends on DEBUG_KERNEL |
239 | select FUNCTION_TRACER | 240 | select FUNCTION_TRACER |
240 | select STACKTRACE | 241 | select STACKTRACE |
242 | select KALLSYMS | ||
241 | help | 243 | help |
242 | This special tracer records the maximum stack footprint of the | 244 | This special tracer records the maximum stack footprint of the |
243 | kernel and displays it in debugfs/tracing/stack_trace. | 245 | kernel and displays it in debugfs/tracing/stack_trace. |
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 9a236ffe2aa4..fdf913dfc7e8 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c | |||
@@ -2033,7 +2033,7 @@ free: | |||
2033 | static int start_graph_tracing(void) | 2033 | static int start_graph_tracing(void) |
2034 | { | 2034 | { |
2035 | struct ftrace_ret_stack **ret_stack_list; | 2035 | struct ftrace_ret_stack **ret_stack_list; |
2036 | int ret; | 2036 | int ret, cpu; |
2037 | 2037 | ||
2038 | ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE * | 2038 | ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE * |
2039 | sizeof(struct ftrace_ret_stack *), | 2039 | sizeof(struct ftrace_ret_stack *), |
@@ -2042,6 +2042,10 @@ static int start_graph_tracing(void) | |||
2042 | if (!ret_stack_list) | 2042 | if (!ret_stack_list) |
2043 | return -ENOMEM; | 2043 | return -ENOMEM; |
2044 | 2044 | ||
2045 | /* The cpu_boot init_task->ret_stack will never be freed */ | ||
2046 | for_each_online_cpu(cpu) | ||
2047 | ftrace_graph_init_task(idle_task(cpu)); | ||
2048 | |||
2045 | do { | 2049 | do { |
2046 | ret = alloc_retstack_tasklist(ret_stack_list); | 2050 | ret = alloc_retstack_tasklist(ret_stack_list); |
2047 | } while (ret == -EAGAIN); | 2051 | } while (ret == -EAGAIN); |
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c index 88c8eb70f54a..bc8e80a86bca 100644 --- a/kernel/trace/trace_selftest.c +++ b/kernel/trace/trace_selftest.c | |||
@@ -23,10 +23,20 @@ static int trace_test_buffer_cpu(struct trace_array *tr, int cpu) | |||
23 | { | 23 | { |
24 | struct ring_buffer_event *event; | 24 | struct ring_buffer_event *event; |
25 | struct trace_entry *entry; | 25 | struct trace_entry *entry; |
26 | unsigned int loops = 0; | ||
26 | 27 | ||
27 | while ((event = ring_buffer_consume(tr->buffer, cpu, NULL))) { | 28 | while ((event = ring_buffer_consume(tr->buffer, cpu, NULL))) { |
28 | entry = ring_buffer_event_data(event); | 29 | entry = ring_buffer_event_data(event); |
29 | 30 | ||
31 | /* | ||
32 | * The ring buffer is a size of trace_buf_size, if | ||
33 | * we loop more than the size, there's something wrong | ||
34 | * with the ring buffer. | ||
35 | */ | ||
36 | if (loops++ > trace_buf_size) { | ||
37 | printk(KERN_CONT ".. bad ring buffer "); | ||
38 | goto failed; | ||
39 | } | ||
30 | if (!trace_valid_entry(entry)) { | 40 | if (!trace_valid_entry(entry)) { |
31 | printk(KERN_CONT ".. invalid entry %d ", | 41 | printk(KERN_CONT ".. invalid entry %d ", |
32 | entry->type); | 42 | entry->type); |
@@ -57,11 +67,20 @@ static int trace_test_buffer(struct trace_array *tr, unsigned long *count) | |||
57 | 67 | ||
58 | cnt = ring_buffer_entries(tr->buffer); | 68 | cnt = ring_buffer_entries(tr->buffer); |
59 | 69 | ||
70 | /* | ||
71 | * The trace_test_buffer_cpu runs a while loop to consume all data. | ||
72 | * If the calling tracer is broken, and is constantly filling | ||
73 | * the buffer, this will run forever, and hard lock the box. | ||
74 | * We disable the ring buffer while we do this test to prevent | ||
75 | * a hard lock up. | ||
76 | */ | ||
77 | tracing_off(); | ||
60 | for_each_possible_cpu(cpu) { | 78 | for_each_possible_cpu(cpu) { |
61 | ret = trace_test_buffer_cpu(tr, cpu); | 79 | ret = trace_test_buffer_cpu(tr, cpu); |
62 | if (ret) | 80 | if (ret) |
63 | break; | 81 | break; |
64 | } | 82 | } |
83 | tracing_on(); | ||
65 | __raw_spin_unlock(&ftrace_max_lock); | 84 | __raw_spin_unlock(&ftrace_max_lock); |
66 | local_irq_restore(flags); | 85 | local_irq_restore(flags); |
67 | 86 | ||