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Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

Browse source 
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (24 commits)
  tracing/urgent: warn in case of ftrace_start_up inbalance
  tracing/urgent: fix unbalanced ftrace_start_up
  function-graph: add stack frame test
  function-graph: disable when both x86_32 and optimize for size are configured
  ring-buffer: have benchmark test print to trace buffer
  ring-buffer: do not grab locks in nmi
  ring-buffer: add locks around rb_per_cpu_empty
  ring-buffer: check for less than two in size allocation
  ring-buffer: remove useless compile check for buffer_page size
  ring-buffer: remove useless warn on check
  ring-buffer: use BUF_PAGE_HDR_SIZE in calculating index
  tracing: update sample event documentation
  tracing/filters: fix race between filter setting and module unload
  tracing/filters: free filter_string in destroy_preds()
  ring-buffer: use commit counters for commit pointer accounting
  ring-buffer: remove unused variable
  ring-buffer: have benchmark test handle discarded events
  ring-buffer: prevent adding write in discarded area
  tracing/filters: strloc should be unsigned short
  tracing/filters: operand can be negative
  ...

Fix up kmemcheck-induced conflict in kernel/trace/ring_buffer.c manually
This commit is contained in:
Linus Torvalds 2009-06-20 10:56:46 -07:00
commit b0b7065b64
19 changed files with 333 additions and 187 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
arch/powerpc/kernel/ftrace.c
View file

@ -586,7 +586,7 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr)
return;
}
if (ftrace_push_return_trace(old, self_addr, &trace.depth) == -EBUSY) {
if (ftrace_push_return_trace(old, self_addr, &trace.depth, 0) == -EBUSY) {
*parent = old;
return;
}

2
arch/s390/kernel/ftrace.c
View file

@ -190,7 +190,7 @@ unsigned long prepare_ftrace_return(unsigned long ip, unsigned long parent)
goto out;
if (unlikely(atomic_read(&current->tracing_graph_pause)))
goto out;
if (ftrace_push_return_trace(parent, ip, &trace.depth) == -EBUSY)
if (ftrace_push_return_trace(parent, ip, &trace.depth, 0) == -EBUSY)
goto out;
trace.func = ftrace_mcount_call_adjust(ip) & PSW_ADDR_INSN;
/* Only trace if the calling function expects to. */

1
arch/x86/Kconfig
View file

@ -34,6 +34,7 @@ config X86
select HAVE_DYNAMIC_FTRACE
select HAVE_FUNCTION_TRACER
select HAVE_FUNCTION_GRAPH_TRACER
select HAVE_FUNCTION_GRAPH_FP_TEST
select HAVE_FUNCTION_TRACE_MCOUNT_TEST
select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
select HAVE_FTRACE_SYSCALLS

2
arch/x86/kernel/entry_32.S
View file

@ -1174,6 +1174,7 @@ ENTRY(ftrace_graph_caller)
pushl %edx
movl 0xc(%esp), %edx
lea 0x4(%ebp), %eax
movl (%ebp), %ecx
subl $MCOUNT_INSN_SIZE, %edx
call prepare_ftrace_return
popl %edx
@ -1188,6 +1189,7 @@ return_to_handler:
pushl %eax
pushl %ecx
pushl %edx
movl %ebp, %eax
call ftrace_return_to_handler
movl %eax, 0xc(%esp)
popl %edx

2
arch/x86/kernel/entry_64.S
View file

@ -135,6 +135,7 @@ ENTRY(ftrace_graph_caller)
leaq 8(%rbp), %rdi
movq 0x38(%rsp), %rsi
movq (%rbp), %rdx
subq $MCOUNT_INSN_SIZE, %rsi
call prepare_ftrace_return
@ -150,6 +151,7 @@ GLOBAL(return_to_handler)
/* Save the return values */
movq %rax, (%rsp)
movq %rdx, 8(%rsp)
movq %rbp, %rdi
call ftrace_return_to_handler

6
arch/x86/kernel/ftrace.c
View file

@ -408,7 +408,8 @@ int ftrace_disable_ftrace_graph_caller(void)
* Hook the return address and push it in the stack of return addrs
* in current thread info.
*/
void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr)
void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr,
unsigned long frame_pointer)
{
unsigned long old;
int faulted;
@ -453,7 +454,8 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr)
return;
}
if (ftrace_push_return_trace(old, self_addr, &trace.depth) == -EBUSY) {
if (ftrace_push_return_trace(old, self_addr, &trace.depth,
frame_pointer) == -EBUSY) {
*parent = old;
return;
}

4
include/linux/ftrace.h
View file

@ -362,6 +362,7 @@ struct ftrace_ret_stack {
unsigned long func;
unsigned long long calltime;
unsigned long long subtime;
unsigned long fp;
};
/*
@ -372,7 +373,8 @@ struct ftrace_ret_stack {
extern void return_to_handler(void);
extern int
ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth);
ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
unsigned long frame_pointer);
/*
* Sometimes we don't want to trace a function with the function

2
include/linux/trace_seq.h
View file

@ -3,6 +3,8 @@
#include <linux/fs.h>
#include <asm/page.h>
/*
* Trace sequences are used to allow a function to call several other functions
* to create a string of data to use (up to a max of PAGE_SIZE.

8
kernel/trace/Kconfig
View file

@ -18,6 +18,13 @@ config HAVE_FUNCTION_TRACER
config HAVE_FUNCTION_GRAPH_TRACER
bool
config HAVE_FUNCTION_GRAPH_FP_TEST
bool
help
An arch may pass in a unique value (frame pointer) to both the
entering and exiting of a function. On exit, the value is compared
and if it does not match, then it will panic the kernel.
config HAVE_FUNCTION_TRACE_MCOUNT_TEST
bool
help
@ -121,6 +128,7 @@ config FUNCTION_GRAPH_TRACER
bool "Kernel Function Graph Tracer"
depends on HAVE_FUNCTION_GRAPH_TRACER
depends on FUNCTION_TRACER
depends on !X86_32 || !CC_OPTIMIZE_FOR_SIZE
default y
help
Enable the kernel to trace a function at both its return

7
kernel/trace/ftrace.c
View file

@ -1224,6 +1224,13 @@ static void ftrace_shutdown(int command)
return;
ftrace_start_up--;
/*
* Just warn in case of unbalance, no need to kill ftrace, it's not
* critical but the ftrace_call callers may be never nopped again after
* further ftrace uses.
*/
WARN_ON_ONCE(ftrace_start_up < 0);
if (!ftrace_start_up)
command |= FTRACE_DISABLE_CALLS;

2
kernel/trace/kmemtrace.c
View file

@ -186,7 +186,7 @@ static int kmem_trace_init(struct trace_array *tr)
int cpu;
kmemtrace_array = tr;
for_each_cpu_mask(cpu, cpu_possible_map)
for_each_cpu(cpu, cpu_possible_mask)
tracing_reset(tr, cpu);
kmemtrace_start_probes();

313
kernel/trace/ring_buffer.c
View file

@ -206,6 +206,7 @@ EXPORT_SYMBOL_GPL(tracing_is_on);
#define RB_EVNT_HDR_SIZE (offsetof(struct ring_buffer_event, array))
#define RB_ALIGNMENT 4U
#define RB_MAX_SMALL_DATA (RB_ALIGNMENT * RINGBUF_TYPE_DATA_TYPE_LEN_MAX)
#define RB_EVNT_MIN_SIZE 8U /* two 32bit words */
/* define RINGBUF_TYPE_DATA for 'case RINGBUF_TYPE_DATA:' */
#define RINGBUF_TYPE_DATA 0 ... RINGBUF_TYPE_DATA_TYPE_LEN_MAX
@ -415,6 +416,8 @@ struct ring_buffer_per_cpu {
unsigned long overrun;
unsigned long read;
local_t entries;
local_t committing;
local_t commits;
u64 write_stamp;
u64 read_stamp;
atomic_t record_disabled;
@ -618,12 +621,6 @@ static void rb_free_cpu_buffer(struct ring_buffer_per_cpu *cpu_buffer)
kfree(cpu_buffer);
}
/*
* Causes compile errors if the struct buffer_page gets bigger
* than the struct page.
*/
extern int ring_buffer_page_too_big(void);
#ifdef CONFIG_HOTPLUG_CPU
static int rb_cpu_notify(struct notifier_block *self,
unsigned long action, void *hcpu);
@ -646,11 +643,6 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags,
int bsize;
int cpu;
/* Paranoid! Optimizes out when all is well */
if (sizeof(struct buffer_page) > sizeof(struct page))
ring_buffer_page_too_big();
/* keep it in its own cache line */
buffer = kzalloc(ALIGN(sizeof(*buffer), cache_line_size()),
GFP_KERNEL);
@ -666,8 +658,8 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags,
buffer->reader_lock_key = key;
/* need at least two pages */
if (buffer->pages == 1)
buffer->pages++;
if (buffer->pages < 2)
buffer->pages = 2;
/*
* In case of non-hotplug cpu, if the ring-buffer is allocated
@ -1011,12 +1003,12 @@ rb_event_index(struct ring_buffer_event *event)
{
unsigned long addr = (unsigned long)event;
return (addr & ~PAGE_MASK) - (PAGE_SIZE - BUF_PAGE_SIZE);
return (addr & ~PAGE_MASK) - BUF_PAGE_HDR_SIZE;
}
static inline int
rb_is_commit(struct ring_buffer_per_cpu *cpu_buffer,
struct ring_buffer_event *event)
rb_event_is_commit(struct ring_buffer_per_cpu *cpu_buffer,
struct ring_buffer_event *event)
{
unsigned long addr = (unsigned long)event;
unsigned long index;
@ -1028,31 +1020,6 @@ rb_is_commit(struct ring_buffer_per_cpu *cpu_buffer,
rb_commit_index(cpu_buffer) == index;
}
static void
rb_set_commit_event(struct ring_buffer_per_cpu *cpu_buffer,
struct ring_buffer_event *event)
{
unsigned long addr = (unsigned long)event;
unsigned long index;
index = rb_event_index(event);
addr &= PAGE_MASK;
while (cpu_buffer->commit_page->page != (void *)addr) {
if (RB_WARN_ON(cpu_buffer,
cpu_buffer->commit_page == cpu_buffer->tail_page))
return;
cpu_buffer->commit_page->page->commit =
cpu_buffer->commit_page->write;
rb_inc_page(cpu_buffer, &cpu_buffer->commit_page);
cpu_buffer->write_stamp =
cpu_buffer->commit_page->page->time_stamp;
}
/* Now set the commit to the event's index */
local_set(&cpu_buffer->commit_page->page->commit, index);
}
static void
rb_set_commit_to_write(struct ring_buffer_per_cpu *cpu_buffer)
{
@ -1171,6 +1138,60 @@ static unsigned rb_calculate_event_length(unsigned length)
return length;
}
static inline void
rb_reset_tail(struct ring_buffer_per_cpu *cpu_buffer,
struct buffer_page *tail_page,
unsigned long tail, unsigned long length)
{
struct ring_buffer_event *event;
/*
* Only the event that crossed the page boundary
* must fill the old tail_page with padding.
*/
if (tail >= BUF_PAGE_SIZE) {
local_sub(length, &tail_page->write);
return;
}
event = __rb_page_index(tail_page, tail);
kmemcheck_annotate_bitfield(event, bitfield);
/*
* If this event is bigger than the minimum size, then
* we need to be careful that we don't subtract the
* write counter enough to allow another writer to slip
* in on this page.
* We put in a discarded commit instead, to make sure
* that this space is not used again.
*
* If we are less than the minimum size, we don't need to
* worry about it.
*/
if (tail > (BUF_PAGE_SIZE - RB_EVNT_MIN_SIZE)) {
/* No room for any events */
/* Mark the rest of the page with padding */
rb_event_set_padding(event);
/* Set the write back to the previous setting */
local_sub(length, &tail_page->write);
return;
}
/* Put in a discarded event */
event->array[0] = (BUF_PAGE_SIZE - tail) - RB_EVNT_HDR_SIZE;
event->type_len = RINGBUF_TYPE_PADDING;
/* time delta must be non zero */
event->time_delta = 1;
/* Account for this as an entry */
local_inc(&tail_page->entries);
local_inc(&cpu_buffer->entries);
/* Set write to end of buffer */
length = (tail + length) - BUF_PAGE_SIZE;
local_sub(length, &tail_page->write);
}
static struct ring_buffer_event *
rb_move_tail(struct ring_buffer_per_cpu *cpu_buffer,
@ -1180,7 +1201,6 @@ rb_move_tail(struct ring_buffer_per_cpu *cpu_buffer,
{
struct buffer_page *next_page, *head_page, *reader_page;
struct ring_buffer *buffer = cpu_buffer->buffer;
struct ring_buffer_event *event;
bool lock_taken = false;
unsigned long flags;
@ -1265,27 +1285,7 @@ rb_move_tail(struct ring_buffer_per_cpu *cpu_buffer,
cpu_buffer->tail_page->page->time_stamp = *ts;
}
/*
* The actual tail page has moved forward.
*/
if (tail < BUF_PAGE_SIZE) {
/* Mark the rest of the page with padding */
event = __rb_page_index(tail_page, tail);
kmemcheck_annotate_bitfield(event, bitfield);
rb_event_set_padding(event);
}
/* Set the write back to the previous setting */
local_sub(length, &tail_page->write);
/*
* If this was a commit entry that failed,
* increment that too
*/
if (tail_page == cpu_buffer->commit_page &&
tail == rb_commit_index(cpu_buffer)) {
rb_set_commit_to_write(cpu_buffer);
}
rb_reset_tail(cpu_buffer, tail_page, tail, length);
__raw_spin_unlock(&cpu_buffer->lock);
local_irq_restore(flags);
@ -1295,7 +1295,7 @@ rb_move_tail(struct ring_buffer_per_cpu *cpu_buffer,
out_reset:
/* reset write */
local_sub(length, &tail_page->write);
rb_reset_tail(cpu_buffer, tail_page, tail, length);
if (likely(lock_taken))
__raw_spin_unlock(&cpu_buffer->lock);
@ -1325,9 +1325,6 @@ __rb_reserve_next(struct ring_buffer_per_cpu *cpu_buffer,
/* We reserved something on the buffer */
if (RB_WARN_ON(cpu_buffer, write > BUF_PAGE_SIZE))
return NULL;
event = __rb_page_index(tail_page, tail);
kmemcheck_annotate_bitfield(event, bitfield);
rb_update_event(event, type, length);
@ -1337,11 +1334,11 @@ __rb_reserve_next(struct ring_buffer_per_cpu *cpu_buffer,
local_inc(&tail_page->entries);
/*
* If this is a commit and the tail is zero, then update
* this page's time stamp.
* If this is the first commit on the page, then update
* its timestamp.
*/
if (!tail && rb_is_commit(cpu_buffer, event))
cpu_buffer->commit_page->page->time_stamp = *ts;
if (!tail)
tail_page->page->time_stamp = *ts;
return event;
}
@ -1410,16 +1407,16 @@ rb_add_time_stamp(struct ring_buffer_per_cpu *cpu_buffer,
return -EAGAIN;
/* Only a commited time event can update the write stamp */
if (rb_is_commit(cpu_buffer, event)) {
if (rb_event_is_commit(cpu_buffer, event)) {
/*
* If this is the first on the page, then we need to
* update the page itself, and just put in a zero.
* If this is the first on the page, then it was
* updated with the page itself. Try to discard it
* and if we can't just make it zero.
*/
if (rb_event_index(event)) {
event->time_delta = *delta & TS_MASK;
event->array[0] = *delta >> TS_SHIFT;
} else {
cpu_buffer->commit_page->page->time_stamp = *ts;
/* try to discard, since we do not need this */
if (!rb_try_to_discard(cpu_buffer, event)) {
/* nope, just zero it */
@ -1445,6 +1442,44 @@ rb_add_time_stamp(struct ring_buffer_per_cpu *cpu_buffer,
return ret;
}
static void rb_start_commit(struct ring_buffer_per_cpu *cpu_buffer)
{
local_inc(&cpu_buffer->committing);
local_inc(&cpu_buffer->commits);
}
static void rb_end_commit(struct ring_buffer_per_cpu *cpu_buffer)
{
unsigned long commits;
if (RB_WARN_ON(cpu_buffer,
!local_read(&cpu_buffer->committing)))
return;
again:
commits = local_read(&cpu_buffer->commits);
/* synchronize with interrupts */
barrier();
if (local_read(&cpu_buffer->committing) == 1)
rb_set_commit_to_write(cpu_buffer);
local_dec(&cpu_buffer->committing);
/* synchronize with interrupts */
barrier();
/*
* Need to account for interrupts coming in between the
* updating of the commit page and the clearing of the
* committing counter.
*/
if (unlikely(local_read(&cpu_buffer->commits) != commits) &&
!local_read(&cpu_buffer->committing)) {
local_inc(&cpu_buffer->committing);
goto again;
}
}
static struct ring_buffer_event *
rb_reserve_next_event(struct ring_buffer_per_cpu *cpu_buffer,
unsigned long length)
@ -1454,6 +1489,8 @@ rb_reserve_next_event(struct ring_buffer_per_cpu *cpu_buffer,
int commit = 0;
int nr_loops = 0;
rb_start_commit(cpu_buffer);
length = rb_calculate_event_length(length);
again:
/*
@ -1466,7 +1503,7 @@ rb_reserve_next_event(struct ring_buffer_per_cpu *cpu_buffer,
* Bail!
*/
if (RB_WARN_ON(cpu_buffer, ++nr_loops > 1000))
return NULL;
goto out_fail;
ts = rb_time_stamp(cpu_buffer->buffer, cpu_buffer->cpu);
@ -1497,7 +1534,7 @@ rb_reserve_next_event(struct ring_buffer_per_cpu *cpu_buffer,
commit = rb_add_time_stamp(cpu_buffer, &ts, &delta);
if (commit == -EBUSY)
return NULL;
goto out_fail;
if (commit == -EAGAIN)
goto again;
@ -1511,28 +1548,19 @@ rb_reserve_next_event(struct ring_buffer_per_cpu *cpu_buffer,
if (unlikely(PTR_ERR(event) == -EAGAIN))
goto again;
if (!event) {
if (unlikely(commit))
/*
* Ouch! We needed a timestamp and it was commited. But
* we didn't get our event reserved.
*/
rb_set_commit_to_write(cpu_buffer);
return NULL;
}
if (!event)
goto out_fail;
/*
* If the timestamp was commited, make the commit our entry
* now so that we will update it when needed.
*/
if (unlikely(commit))
rb_set_commit_event(cpu_buffer, event);
else if (!rb_is_commit(cpu_buffer, event))
if (!rb_event_is_commit(cpu_buffer, event))
delta = 0;
event->time_delta = delta;
return event;
out_fail:
rb_end_commit(cpu_buffer);
return NULL;
}
#define TRACE_RECURSIVE_DEPTH 16
@ -1642,13 +1670,14 @@ static void rb_commit(struct ring_buffer_per_cpu *cpu_buffer,
{
local_inc(&cpu_buffer->entries);
/* Only process further if we own the commit */
if (!rb_is_commit(cpu_buffer, event))
return;
/*
* The event first in the commit queue updates the
* time stamp.
*/
if (rb_event_is_commit(cpu_buffer, event))
cpu_buffer->write_stamp += event->time_delta;
cpu_buffer->write_stamp += event->time_delta;
rb_set_commit_to_write(cpu_buffer);
rb_end_commit(cpu_buffer);
}
/**
@ -1737,15 +1766,15 @@ void ring_buffer_discard_commit(struct ring_buffer *buffer,
/* The event is discarded regardless */
rb_event_discard(event);
cpu = smp_processor_id();
cpu_buffer = buffer->buffers[cpu];
/*
* This must only be called if the event has not been
* committed yet. Thus we can assume that preemption
* is still disabled.
*/
RB_WARN_ON(buffer, preemptible());
cpu = smp_processor_id();
cpu_buffer = buffer->buffers[cpu];
RB_WARN_ON(buffer, !local_read(&cpu_buffer->committing));
if (!rb_try_to_discard(cpu_buffer, event))
goto out;
@ -1756,13 +1785,7 @@ void ring_buffer_discard_commit(struct ring_buffer *buffer,
*/
local_inc(&cpu_buffer->entries);
out:
/*
* If a write came in and pushed the tail page
* we still need to update the commit pointer
* if we were the commit.
*/
if (rb_is_commit(cpu_buffer, event))
rb_set_commit_to_write(cpu_buffer);
rb_end_commit(cpu_buffer);
trace_recursive_unlock();
@ -2446,6 +2469,21 @@ rb_iter_peek(struct ring_buffer_iter *iter, u64 *ts)
}
EXPORT_SYMBOL_GPL(ring_buffer_iter_peek);
static inline int rb_ok_to_lock(void)
{
/*
* If an NMI die dumps out the content of the ring buffer
* do not grab locks. We also permanently disable the ring
* buffer too. A one time deal is all you get from reading
* the ring buffer from an NMI.
*/
if (likely(!in_nmi() && !oops_in_progress))
return 1;
tracing_off_permanent();
return 0;
}
/**
* ring_buffer_peek - peek at the next event to be read
* @buffer: The ring buffer to read
@ -2461,14 +2499,20 @@ ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts)
struct ring_buffer_per_cpu *cpu_buffer = buffer->buffers[cpu];
struct ring_buffer_event *event;
unsigned long flags;
int dolock;
if (!cpumask_test_cpu(cpu, buffer->cpumask))
return NULL;
dolock = rb_ok_to_lock();
again:
spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
local_irq_save(flags);
if (dolock)
spin_lock(&cpu_buffer->reader_lock);
event = rb_buffer_peek(buffer, cpu, ts);
spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
if (dolock)
spin_unlock(&cpu_buffer->reader_lock);
local_irq_restore(flags);
if (event && event->type_len == RINGBUF_TYPE_PADDING) {
cpu_relax();
@ -2520,6 +2564,9 @@ ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts)
struct ring_buffer_per_cpu *cpu_buffer;
struct ring_buffer_event *event = NULL;
unsigned long flags;
int dolock;
dolock = rb_ok_to_lock();
again:
/* might be called in atomic */
@ -2529,7 +2576,9 @@ ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts)
goto out;
cpu_buffer = buffer->buffers[cpu];
spin_lock_irqsave(&cpu_buffer->reader_lock, flags);
local_irq_save(flags);
if (dolock)
spin_lock(&cpu_buffer->reader_lock);
event = rb_buffer_peek(buffer, cpu, ts);
if (!event)
@ -2538,7 +2587,9 @@ ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts)
rb_advance_reader(cpu_buffer);
out_unlock:
spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
if (dolock)
spin_unlock(&cpu_buffer->reader_lock);
local_irq_restore(flags);
out:
preempt_enable();
@ -2680,6 +2731,8 @@ rb_reset_cpu(struct ring_buffer_per_cpu *cpu_buffer)
cpu_buffer->overrun = 0;
cpu_buffer->read = 0;
local_set(&cpu_buffer->entries, 0);
local_set(&cpu_buffer->committing, 0);
local_set(&cpu_buffer->commits, 0);
cpu_buffer->write_stamp = 0;
cpu_buffer->read_stamp = 0;
@ -2734,12 +2787,25 @@ EXPORT_SYMBOL_GPL(ring_buffer_reset);
int ring_buffer_empty(struct ring_buffer *buffer)
{
struct ring_buffer_per_cpu *cpu_buffer;
unsigned long flags;
int dolock;
int cpu;
int ret;
dolock = rb_ok_to_lock();
/* yes this is racy, but if you don't like the race, lock the buffer */
for_each_buffer_cpu(buffer, cpu) {
cpu_buffer = buffer->buffers[cpu];
if (!rb_per_cpu_empty(cpu_buffer))
local_irq_save(flags);
if (dolock)
spin_lock(&cpu_buffer->reader_lock);
ret = rb_per_cpu_empty(cpu_buffer);
if (dolock)
spin_unlock(&cpu_buffer->reader_lock);
local_irq_restore(flags);
if (!ret)
return 0;
}
@ -2755,14 +2821,23 @@ EXPORT_SYMBOL_GPL(ring_buffer_empty);
int ring_buffer_empty_cpu(struct ring_buffer *buffer, int cpu)
{
struct ring_buffer_per_cpu *cpu_buffer;
unsigned long flags;
int dolock;
int ret;
if (!cpumask_test_cpu(cpu, buffer->cpumask))
return 1;
cpu_buffer = buffer->buffers[cpu];
ret = rb_per_cpu_empty(cpu_buffer);
dolock = rb_ok_to_lock();
cpu_buffer = buffer->buffers[cpu];
local_irq_save(flags);
if (dolock)
spin_lock(&cpu_buffer->reader_lock);
ret = rb_per_cpu_empty(cpu_buffer);
if (dolock)
spin_unlock(&cpu_buffer->reader_lock);
local_irq_restore(flags);
return ret;
}
@ -3108,7 +3183,7 @@ static int rb_cpu_notify(struct notifier_block *self,
switch (action) {
case CPU_UP_PREPARE:
case CPU_UP_PREPARE_FROZEN:
if (cpu_isset(cpu, *buffer->cpumask))
if (cpumask_test_cpu(cpu, buffer->cpumask))
return NOTIFY_OK;
buffer->buffers[cpu] =
@ -3119,7 +3194,7 @@ static int rb_cpu_notify(struct notifier_block *self,
return NOTIFY_OK;
}
smp_wmb();
cpu_set(cpu, *buffer->cpumask);
cpumask_set_cpu(cpu, buffer->cpumask);
break;
case CPU_DOWN_PREPARE:
case CPU_DOWN_PREPARE_FROZEN:

45
kernel/trace/ring_buffer_benchmark.c
View file

@ -102,8 +102,10 @@ static enum event_status read_page(int cpu)
event = (void *)&rpage->data[i];
switch (event->type_len) {
case RINGBUF_TYPE_PADDING:
/* We don't expect any padding */
KILL_TEST();
/* failed writes may be discarded events */
if (!event->time_delta)
KILL_TEST();
inc = event->array[0] + 4;
break;
case RINGBUF_TYPE_TIME_EXTEND:
inc = 8;
@ -119,7 +121,7 @@ static enum event_status read_page(int cpu)
KILL_TEST();
break;
}
inc = event->array[0];
inc = event->array[0] + 4;
break;
default:
entry = ring_buffer_event_data(event);
@ -201,7 +203,7 @@ static void ring_buffer_producer(void)
* Hammer the buffer for 10 secs (this may
* make the system stall)
*/
pr_info("Starting ring buffer hammer\n");
trace_printk("Starting ring buffer hammer\n");
do_gettimeofday(&start_tv);
do {
struct ring_buffer_event *event;
@ -237,7 +239,7 @@ static void ring_buffer_producer(void)
#endif
} while (end_tv.tv_sec < (start_tv.tv_sec + RUN_TIME) && !kill_test);
pr_info("End ring buffer hammer\n");
trace_printk("End ring buffer hammer\n");
if (consumer) {
/* Init both completions here to avoid races */
@ -260,49 +262,50 @@ static void ring_buffer_producer(void)
overruns = ring_buffer_overruns(buffer);
if (kill_test)
pr_info("ERROR!\n");
pr_info("Time: %lld (usecs)\n", time);
pr_info("Overruns: %lld\n", overruns);
trace_printk("ERROR!\n");
trace_printk("Time: %lld (usecs)\n", time);
trace_printk("Overruns: %lld\n", overruns);
if (disable_reader)
pr_info("Read: (reader disabled)\n");
trace_printk("Read: (reader disabled)\n");
else
pr_info("Read: %ld (by %s)\n", read,
trace_printk("Read: %ld (by %s)\n", read,
read_events ? "events" : "pages");
pr_info("Entries: %lld\n", entries);
pr_info("Total: %lld\n", entries + overruns + read);
pr_info("Missed: %ld\n", missed);
pr_info("Hit: %ld\n", hit);
trace_printk("Entries: %lld\n", entries);
trace_printk("Total: %lld\n", entries + overruns + read);
trace_printk("Missed: %ld\n", missed);
trace_printk("Hit: %ld\n", hit);
/* Convert time from usecs to millisecs */
do_div(time, USEC_PER_MSEC);
if (time)
hit /= (long)time;
else
pr_info("TIME IS ZERO??\n");
trace_printk("TIME IS ZERO??\n");
pr_info("Entries per millisec: %ld\n", hit);
trace_printk("Entries per millisec: %ld\n", hit);
if (hit) {
/* Calculate the average time in nanosecs */
avg = NSEC_PER_MSEC / hit;
pr_info("%ld ns per entry\n", avg);
trace_printk("%ld ns per entry\n", avg);
}
if (missed) {
if (time)
missed /= (long)time;
pr_info("Total iterations per millisec: %ld\n", hit + missed);
trace_printk("Total iterations per millisec: %ld\n",
hit + missed);
/* it is possible that hit + missed will overflow and be zero */
if (!(hit + missed)) {
pr_info("hit + missed overflowed and totalled zero!\n");
trace_printk("hit + missed overflowed and totalled zero!\n");
hit--; /* make it non zero */
}
/* Caculate the average time in nanosecs */
avg = NSEC_PER_MSEC / (hit + missed);
pr_info("%ld ns per entry\n", avg);
trace_printk("%ld ns per entry\n", avg);
}
}
@ -353,7 +356,7 @@ static int ring_buffer_producer_thread(void *arg)
ring_buffer_producer();
pr_info("Sleeping for 10 secs\n");
trace_printk("Sleeping for 10 secs\n");
set_current_state(TASK_INTERRUPTIBLE);
schedule_timeout(HZ * SLEEP_TIME);
__set_current_state(TASK_RUNNING);

8
kernel/trace/trace.c
View file

@ -2191,11 +2191,12 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL))
return -ENOMEM;
mutex_lock(&tracing_cpumask_update_lock);
err = cpumask_parse_user(ubuf, count, tracing_cpumask_new);
if (err)
goto err_unlock;
mutex_lock(&tracing_cpumask_update_lock);
local_irq_disable();
__raw_spin_lock(&ftrace_max_lock);
for_each_tracing_cpu(cpu) {
@ -2223,8 +2224,7 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
return count;
err_unlock:
mutex_unlock(&tracing_cpumask_update_lock);
free_cpumask_var(tracing_cpumask);
free_cpumask_var(tracing_cpumask_new);
return err;
}
@ -3626,7 +3626,7 @@ tracing_stats_read(struct file *filp, char __user *ubuf,
struct trace_seq *s;
unsigned long cnt;
s = kmalloc(sizeof(*s), GFP_ATOMIC);
s = kmalloc(sizeof(*s), GFP_KERNEL);
if (!s)
return ENOMEM;

37
kernel/trace/trace_events_filter.c
View file

@ -27,8 +27,6 @@
#include "trace.h"
#include "trace_output.h"
static DEFINE_MUTEX(filter_mutex);
enum filter_op_ids
{
OP_OR,
@ -178,7 +176,7 @@ static int filter_pred_string(struct filter_pred *pred, void *event,
static int filter_pred_strloc(struct filter_pred *pred, void *event,
int val1, int val2)
{
int str_loc = *(int *)(event + pred->offset);
unsigned short str_loc = *(unsigned short *)(event + pred->offset);
char *addr = (char *)(event + str_loc);
int cmp, match;
@ -294,12 +292,12 @@ void print_event_filter(struct ftrace_event_call *call, struct trace_seq *s)
{
struct event_filter *filter = call->filter;
mutex_lock(&filter_mutex);
mutex_lock(&event_mutex);
if (filter->filter_string)
trace_seq_printf(s, "%s\n", filter->filter_string);
else
trace_seq_printf(s, "none\n");
mutex_unlock(&filter_mutex);
mutex_unlock(&event_mutex);
}
void print_subsystem_event_filter(struct event_subsystem *system,
@ -307,12 +305,12 @@ void print_subsystem_event_filter(struct event_subsystem *system,
{
struct event_filter *filter = system->filter;
mutex_lock(&filter_mutex);
mutex_lock(&event_mutex);
if (filter->filter_string)
trace_seq_printf(s, "%s\n", filter->filter_string);
else
trace_seq_printf(s, "none\n");
mutex_unlock(&filter_mutex);
mutex_unlock(&event_mutex);
}
static struct ftrace_event_field *
@ -381,6 +379,7 @@ void destroy_preds(struct ftrace_event_call *call)
filter_free_pred(filter->preds[i]);
}
kfree(filter->preds);
kfree(filter->filter_string);
kfree(filter);
call->filter = NULL;
}
@ -433,7 +432,6 @@ static void filter_free_subsystem_preds(struct event_subsystem *system)
filter->n_preds = 0;
}
mutex_lock(&event_mutex);
list_for_each_entry(call, &ftrace_events, list) {
if (!call->define_fields)
continue;
@ -443,7 +441,6 @@ static void filter_free_subsystem_preds(struct event_subsystem *system)
remove_filter_string(call->filter);
}
}
mutex_unlock(&event_mutex);
}
static int filter_add_pred_fn(struct filter_parse_state *ps,
@ -546,6 +543,7 @@ static int filter_add_pred(struct filter_parse_state *ps,
filter_pred_fn_t fn;
unsigned long long val;
int string_type;
int ret;
pred->fn = filter_pred_none;
@ -581,7 +579,11 @@ static int filter_add_pred(struct filter_parse_state *ps,
pred->not = 1;
return filter_add_pred_fn(ps, call, pred, fn);
} else {
if (strict_strtoull(pred->str_val, 0, &val)) {
if (field->is_signed)
ret = strict_strtoll(pred->str_val, 0, &val);
else
ret = strict_strtoull(pred->str_val, 0, &val);
if (ret) {
parse_error(ps, FILT_ERR_ILLEGAL_INTVAL, 0);
return -EINVAL;
}
@ -625,7 +627,6 @@ static int filter_add_subsystem_pred(struct filter_parse_state *ps,
filter->preds[filter->n_preds] = pred;
filter->n_preds++;
mutex_lock(&event_mutex);
list_for_each_entry(call, &ftrace_events, list) {
if (!call->define_fields)
@ -636,14 +637,12 @@ static int filter_add_subsystem_pred(struct filter_parse_state *ps,
err = filter_add_pred(ps, call, pred);
if (err) {
mutex_unlock(&event_mutex);
filter_free_subsystem_preds(system);
parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0);
goto out;
}
replace_filter_string(call->filter, filter_string);
}
mutex_unlock(&event_mutex);
out:
return err;
}
@ -1070,12 +1069,12 @@ int apply_event_filter(struct ftrace_event_call *call, char *filter_string)
struct filter_parse_state *ps;
mutex_lock(&filter_mutex);
mutex_lock(&event_mutex);
if (!strcmp(strstrip(filter_string), "0")) {
filter_disable_preds(call);
remove_filter_string(call->filter);
mutex_unlock(&filter_mutex);
mutex_unlock(&event_mutex);
return 0;
}
@ -1103,7 +1102,7 @@ out:
postfix_clear(ps);
kfree(ps);
out_unlock:
mutex_unlock(&filter_mutex);
mutex_unlock(&event_mutex);
return err;
}
@ -1115,12 +1114,12 @@ int apply_subsystem_event_filter(struct event_subsystem *system,
struct filter_parse_state *ps;
mutex_lock(&filter_mutex);
mutex_lock(&event_mutex);
if (!strcmp(strstrip(filter_string), "0")) {
filter_free_subsystem_preds(system);
remove_filter_string(system->filter);
mutex_unlock(&filter_mutex);
mutex_unlock(&event_mutex);
return 0;
}
@ -1148,7 +1147,7 @@ out:
postfix_clear(ps);
kfree(ps);
out_unlock:
mutex_unlock(&filter_mutex);
mutex_unlock(&event_mutex);
return err;
}

8
kernel/trace/trace_functions.c
View file

@ -193,9 +193,11 @@ static void tracing_start_function_trace(void)
static void tracing_stop_function_trace(void)
{
ftrace_function_enabled = 0;
/* OK if they are not registered */
unregister_ftrace_function(&trace_stack_ops);
unregister_ftrace_function(&trace_ops);
if (func_flags.val & TRACE_FUNC_OPT_STACK)
unregister_ftrace_function(&trace_stack_ops);
else
unregister_ftrace_function(&trace_ops);
}
static int func_set_flag(u32 old_flags, u32 bit, int set)

36
kernel/trace/trace_functions_graph.c
View file

@ -57,7 +57,8 @@ static struct tracer_flags tracer_flags = {
/* Add a function return address to the trace stack on thread info.*/
int
ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth)
ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
unsigned long frame_pointer)
{
unsigned long long calltime;
int index;
@ -85,6 +86,7 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth)
current->ret_stack[index].func = func;
current->ret_stack[index].calltime = calltime;
current->ret_stack[index].subtime = 0;
current->ret_stack[index].fp = frame_pointer;
*depth = index;
return 0;
@ -92,7 +94,8 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth)
/* Retrieve a function return address to the trace stack on thread info.*/
static void
ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret)
ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret,
unsigned long frame_pointer)
{
int index;
@ -106,6 +109,31 @@ ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret)
return;
}
#ifdef CONFIG_HAVE_FUNCTION_GRAPH_FP_TEST
/*
* The arch may choose to record the frame pointer used
* and check it here to make sure that it is what we expect it
* to be. If gcc does not set the place holder of the return
* address in the frame pointer, and does a copy instead, then
* the function graph trace will fail. This test detects this
* case.
*
* Currently, x86_32 with optimize for size (-Os) makes the latest
* gcc do the above.
*/
if (unlikely(current->ret_stack[index].fp != frame_pointer)) {
ftrace_graph_stop();
WARN(1, "Bad frame pointer: expected %lx, received %lx\n"
" from func %pF return to %lx\n",
current->ret_stack[index].fp,
frame_pointer,
(void *)current->ret_stack[index].func,
current->ret_stack[index].ret);
*ret = (unsigned long)panic;
return;
}
#endif
*ret = current->ret_stack[index].ret;
trace->func = current->ret_stack[index].func;
trace->calltime = current->ret_stack[index].calltime;
@ -117,12 +145,12 @@ ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret)
* Send the trace to the ring-buffer.
* @return the original return address.
*/
unsigned long ftrace_return_to_handler(void)
unsigned long ftrace_return_to_handler(unsigned long frame_pointer)
{
struct ftrace_graph_ret trace;
unsigned long ret;
ftrace_pop_return_trace(&trace, &ret);
ftrace_pop_return_trace(&trace, &ret, frame_pointer);
trace.rettime = trace_clock_local();
ftrace_graph_return(&trace);
barrier();

8
samples/trace_events/Makefile
View file

@ -1,6 +1,14 @@
# builds the trace events example kernel modules;
# then to use one (as root): insmod <module_name.ko>
# If you include a trace header outside of include/trace/events
# then the file that does the #define CREATE_TRACE_POINTS must
# have that tracer file in its main search path. This is because
# define_trace.h will include it, and must be able to find it from
# the include/trace directory.
#
# Here trace-events-sample.c does the CREATE_TRACE_POINTS.
#
CFLAGS_trace-events-sample.o := -I$(src)
obj-$(CONFIG_SAMPLE_TRACE_EVENTS) += trace-events-sample.o

27
samples/trace_events/trace-events-sample.h
View file

@ -19,16 +19,21 @@
* If TRACE_SYSTEM is defined, that will be the directory created
* in the ftrace directory under /debugfs/tracing/events/<system>
*
* The define_trace.h belowe will also look for a file name of
* The define_trace.h below will also look for a file name of
* TRACE_SYSTEM.h where TRACE_SYSTEM is what is defined here.
* In this case, it would look for sample.h
*
* If you want a different system than file name, you can override
* the header name by defining TRACE_INCLUDE_FILE
* If the header name will be different than the system name
* (as in this case), then you can override the header name that
* define_trace.h will look up by defining TRACE_INCLUDE_FILE
*
* If this file was called, goofy.h, then we would define:
* This file is called trace-events-sample.h but we want the system
* to be called "sample". Therefore we must define the name of this
* file:
*
* #define TRACE_INCLUDE_FILE goofy
* #define TRACE_INCLUDE_FILE trace-events-sample
*
* As we do an the bottom of this file.
*/
#undef TRACE_SYSTEM
#define TRACE_SYSTEM sample
@ -99,13 +104,13 @@ TRACE_EVENT(foo_bar,
*
* #define TRACE_INCLUDE_PATH ../../samples/trace_events
*
* But I chose to simply make it use the current directory and then in
* the Makefile I added:
* But the safest and easiest way to simply make it use the directory
* that the file is in is to add in the Makefile:
*
* CFLAGS_trace-events-sample.o := -I$(PWD)/samples/trace_events/
* CFLAGS_trace-events-sample.o := -I$(src)
*
* This will make sure the current path is part of the include
* structure for our file so that we can find it.
* structure for our file so that define_trace.h can find it.
*
* I could have made only the top level directory the include:
*
@ -115,8 +120,8 @@ TRACE_EVENT(foo_bar,
*
* #define TRACE_INCLUDE_PATH samples/trace_events
*
* But then if something defines "samples" or "trace_events" then we
* could risk that being converted too, and give us an unexpected
* But then if something defines "samples" or "trace_events" as a macro
* then we could risk that being converted too, and give us an unexpected
* result.
*/
#undef TRACE_INCLUDE_PATH