Merge branches 'tracing/fastboot', 'tracing/ftrace' and 'tracing/urgent' into tracing/core

This commit is contained in:
Ingo Molnar 2008-11-16 07:28:46 +01:00
commit c91add5fa6
5 changed files with 55 additions and 44 deletions

View file

@ -82,7 +82,7 @@ of ftrace. Here is a list of some of the key files:
tracer is not adding more data, they will display
the same information every time they are read.
iter_ctrl: This file lets the user control the amount of data
trace_options: This file lets the user control the amount of data
that is displayed in one of the above output
files.
@ -94,10 +94,10 @@ of ftrace. Here is a list of some of the key files:
only be recorded if the latency is greater than
the value in this file. (in microseconds)
trace_entries: This sets or displays the number of bytes each CPU
buffer_size_kb: This sets or displays the number of kilobytes each CPU
buffer can hold. The tracer buffers are the same size
for each CPU. The displayed number is the size of the
CPU buffer and not total size of all buffers. The
CPU buffer and not total size of all buffers. The
trace buffers are allocated in pages (blocks of memory
that the kernel uses for allocation, usually 4 KB in size).
If the last page allocated has room for more bytes
@ -316,23 +316,23 @@ The above is mostly meaningful for kernel developers.
The rest is the same as the 'trace' file.
iter_ctrl
---------
trace_options
-------------
The iter_ctrl file is used to control what gets printed in the trace
The trace_options file is used to control what gets printed in the trace
output. To see what is available, simply cat the file:
cat /debug/tracing/iter_ctrl
cat /debug/tracing/trace_options
print-parent nosym-offset nosym-addr noverbose noraw nohex nobin \
noblock nostacktrace nosched-tree
To disable one of the options, echo in the option prepended with "no".
echo noprint-parent > /debug/tracing/iter_ctrl
echo noprint-parent > /debug/tracing/trace_options
To enable an option, leave off the "no".
echo sym-offset > /debug/tracing/iter_ctrl
echo sym-offset > /debug/tracing/trace_options
Here are the available options:
@ -1299,41 +1299,29 @@ trace entries
-------------
Having too much or not enough data can be troublesome in diagnosing
an issue in the kernel. The file trace_entries is used to modify
an issue in the kernel. The file buffer_size_kb is used to modify
the size of the internal trace buffers. The number listed
is the number of entries that can be recorded per CPU. To know
the full size, multiply the number of possible CPUS with the
number of entries.
# cat /debug/tracing/trace_entries
65620
# cat /debug/tracing/buffer_size_kb
1408 (units kilobytes)
Note, to modify this, you must have tracing completely disabled. To do that,
echo "nop" into the current_tracer. If the current_tracer is not set
to "nop", an EINVAL error will be returned.
# echo nop > /debug/tracing/current_tracer
# echo 100000 > /debug/tracing/trace_entries
# cat /debug/tracing/trace_entries
100045
Notice that we echoed in 100,000 but the size is 100,045. The entries
are held in individual pages. It allocates the number of pages it takes
to fulfill the request. If more entries may fit on the last page
then they will be added.
# echo 1 > /debug/tracing/trace_entries
# cat /debug/tracing/trace_entries
85
This shows us that 85 entries can fit in a single page.
# echo 10000 > /debug/tracing/buffer_size_kb
# cat /debug/tracing/buffer_size_kb
10000 (units kilobytes)
The number of pages which will be allocated is limited to a percentage
of available memory. Allocating too much will produce an error.
# echo 1000000000000 > /debug/tracing/trace_entries
# echo 1000000000000 > /debug/tracing/buffer_size_kb
-bash: echo: write error: Cannot allocate memory
# cat /debug/tracing/trace_entries
# cat /debug/tracing/buffer_size_kb
85

View file

@ -179,8 +179,7 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops)
if (ftrace_enabled) {
/* If we only have one func left, then call that directly */
if (ftrace_list == &ftrace_list_end ||
ftrace_list->next == &ftrace_list_end)
if (ftrace_list->next == &ftrace_list_end)
ftrace_trace_function = ftrace_list->func;
}

View file

@ -533,6 +533,12 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size)
LIST_HEAD(pages);
int i, cpu;
/*
* Always succeed at resizing a non-existent buffer:
*/
if (!buffer)
return size;
size = DIV_ROUND_UP(size, BUF_PAGE_SIZE);
size *= BUF_PAGE_SIZE;
buffer_size = buffer->pages * BUF_PAGE_SIZE;

View file

@ -204,8 +204,9 @@ static DEFINE_MUTEX(trace_types_lock);
/* trace_wait is a waitqueue for tasks blocked on trace_poll */
static DECLARE_WAIT_QUEUE_HEAD(trace_wait);
/* trace_flags holds iter_ctrl options */
unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK;
/* trace_flags holds trace_options default values */
unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK |
TRACE_ITER_ANNOTATE;
/**
* trace_wake_up - wake up tasks waiting for trace input
@ -261,6 +262,7 @@ static const char *trace_options[] = {
#ifdef CONFIG_BRANCH_TRACER
"branch",
#endif
"annotate",
NULL
};
@ -1113,6 +1115,7 @@ void tracing_stop_function_trace(void)
enum trace_file_type {
TRACE_FILE_LAT_FMT = 1,
TRACE_FILE_ANNOTATE = 2,
};
static void trace_iterator_increment(struct trace_iterator *iter, int cpu)
@ -1532,6 +1535,12 @@ static void test_cpu_buff_start(struct trace_iterator *iter)
{
struct trace_seq *s = &iter->seq;
if (!(trace_flags & TRACE_ITER_ANNOTATE))
return;
if (!(iter->iter_flags & TRACE_FILE_ANNOTATE))
return;
if (cpu_isset(iter->cpu, iter->started))
return;
@ -2132,6 +2141,11 @@ __tracing_open(struct inode *inode, struct file *file, int *ret)
iter->trace = current_trace;
iter->pos = -1;
/* Annotate start of buffers if we had overruns */
if (ring_buffer_overruns(iter->tr->buffer))
iter->iter_flags |= TRACE_FILE_ANNOTATE;
for_each_tracing_cpu(cpu) {
iter->buffer_iter[cpu] =
@ -2411,7 +2425,7 @@ static struct file_operations tracing_cpumask_fops = {
};
static ssize_t
tracing_iter_ctrl_read(struct file *filp, char __user *ubuf,
tracing_trace_options_read(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
{
char *buf;
@ -2448,7 +2462,7 @@ tracing_iter_ctrl_read(struct file *filp, char __user *ubuf,
}
static ssize_t
tracing_iter_ctrl_write(struct file *filp, const char __user *ubuf,
tracing_trace_options_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
char buf[64];
@ -2493,8 +2507,8 @@ tracing_iter_ctrl_write(struct file *filp, const char __user *ubuf,
static struct file_operations tracing_iter_fops = {
.open = tracing_open_generic,
.read = tracing_iter_ctrl_read,
.write = tracing_iter_ctrl_write,
.read = tracing_trace_options_read,
.write = tracing_trace_options_write,
};
static const char readme_msg[] =
@ -2508,9 +2522,9 @@ static const char readme_msg[] =
"# echo sched_switch > /debug/tracing/current_tracer\n"
"# cat /debug/tracing/current_tracer\n"
"sched_switch\n"
"# cat /debug/tracing/iter_ctrl\n"
"# cat /debug/tracing/trace_options\n"
"noprint-parent nosym-offset nosym-addr noverbose\n"
"# echo print-parent > /debug/tracing/iter_ctrl\n"
"# echo print-parent > /debug/tracing/trace_options\n"
"# echo 1 > /debug/tracing/tracing_enabled\n"
"# cat /debug/tracing/trace > /tmp/trace.txt\n"
"echo 0 > /debug/tracing/tracing_enabled\n"
@ -2905,7 +2919,7 @@ tracing_entries_read(struct file *filp, char __user *ubuf,
char buf[64];
int r;
r = sprintf(buf, "%lu\n", tr->entries);
r = sprintf(buf, "%lu\n", tr->entries >> 10);
return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}
@ -2945,6 +2959,9 @@ tracing_entries_write(struct file *filp, const char __user *ubuf,
atomic_inc(&max_tr.data[cpu]->disabled);
}
/* value is in KB */
val <<= 10;
if (val != global_trace.entries) {
ret = ring_buffer_resize(global_trace.buffer, val);
if (ret < 0) {
@ -3145,10 +3162,10 @@ static __init int tracer_init_debugfs(void)
if (!entry)
pr_warning("Could not create debugfs 'tracing_enabled' entry\n");
entry = debugfs_create_file("iter_ctrl", 0644, d_tracer,
entry = debugfs_create_file("trace_options", 0644, d_tracer,
NULL, &tracing_iter_fops);
if (!entry)
pr_warning("Could not create debugfs 'iter_ctrl' entry\n");
pr_warning("Could not create debugfs 'trace_options' entry\n");
entry = debugfs_create_file("tracing_cpumask", 0644, d_tracer,
NULL, &tracing_cpumask_fops);
@ -3198,11 +3215,11 @@ static __init int tracer_init_debugfs(void)
pr_warning("Could not create debugfs "
"'trace_pipe' entry\n");
entry = debugfs_create_file("trace_entries", 0644, d_tracer,
entry = debugfs_create_file("buffer_size_kb", 0644, d_tracer,
&global_trace, &tracing_entries_fops);
if (!entry)
pr_warning("Could not create debugfs "
"'trace_entries' entry\n");
"'buffer_size_kb' entry\n");
entry = debugfs_create_file("trace_marker", 0220, d_tracer,
NULL, &tracing_mark_fops);

View file

@ -473,6 +473,7 @@ enum trace_iterator_flags {
#ifdef CONFIG_BRANCH_TRACER
TRACE_ITER_BRANCH = 0x1000,
#endif
TRACE_ITER_ANNOTATE = 0x2000,
};
/*