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authorLinus Torvalds <torvalds@linux-foundation.org>2013-04-30 16:41:01 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2013-04-30 16:41:01 +0200
commite0972916e8fe943f342b0dd1c9d43dbf5bc261c2 (patch)
tree690c436f1f9b839c4ba34d17ab3efa63b97a2dce /kernel/trace
parentMerge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kerne... (diff)
parentperf/x86/intel/P4: Robistify P4 PMU types (diff)
downloadlinux-e0972916e8fe943f342b0dd1c9d43dbf5bc261c2.tar.xz
linux-e0972916e8fe943f342b0dd1c9d43dbf5bc261c2.zip
Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar: "Features: - Add "uretprobes" - an optimization to uprobes, like kretprobes are an optimization to kprobes. "perf probe -x file sym%return" now works like kretprobes. By Oleg Nesterov. - Introduce per core aggregation in 'perf stat', from Stephane Eranian. - Add memory profiling via PEBS, from Stephane Eranian. - Event group view for 'annotate' in --stdio, --tui and --gtk, from Namhyung Kim. - Add support for AMD NB and L2I "uncore" counters, by Jacob Shin. - Add Ivy Bridge-EP uncore support, by Zheng Yan - IBM zEnterprise EC12 oprofile support patchlet from Robert Richter. - Add perf test entries for checking breakpoint overflow signal handler issues, from Jiri Olsa. - Add perf test entry for for checking number of EXIT events, from Namhyung Kim. - Add perf test entries for checking --cpu in record and stat, from Jiri Olsa. - Introduce perf stat --repeat forever, from Frederik Deweerdt. - Add --no-demangle to report/top, from Namhyung Kim. - PowerPC fixes plus a couple of cleanups/optimizations in uprobes and trace_uprobes, by Oleg Nesterov. Various fixes and refactorings: - Fix dependency of the python binding wrt libtraceevent, from Naohiro Aota. - Simplify some perf_evlist methods and to allow 'stat' to share code with 'record' and 'trace', by Arnaldo Carvalho de Melo. - Remove dead code in related to libtraceevent integration, from Namhyung Kim. - Revert "perf sched: Handle PERF_RECORD_EXIT events" to get 'perf sched lat' back working, by Arnaldo Carvalho de Melo - We don't use Newt anymore, just plain libslang, by Arnaldo Carvalho de Melo. - Kill a bunch of die() calls, from Namhyung Kim. - Fix build on non-glibc systems due to libio.h absence, from Cody P Schafer. - Remove some perf_session and tracing dead code, from David Ahern. - Honor parallel jobs, fix from Borislav Petkov - Introduce tools/lib/lk library, initially just removing duplication among tools/perf and tools/vm. from Borislav Petkov ... and many more I missed to list, see the shortlog and git log for more details." * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (136 commits) perf/x86/intel/P4: Robistify P4 PMU types perf/x86/amd: Fix AMD NB and L2I "uncore" support perf/x86/amd: Remove old-style NB counter support from perf_event_amd.c perf/x86: Check all MSRs before passing hw check perf/x86/amd: Add support for AMD NB and L2I "uncore" counters perf/x86/intel: Add Ivy Bridge-EP uncore support perf/x86/intel: Fix SNB-EP CBO and PCU uncore PMU filter management perf/x86: Avoid kfree() in CPU_{STARTING,DYING} uprobes/perf: Avoid perf_trace_buf_prepare/submit if ->perf_events is empty uprobes/tracing: Don't pass addr=ip to perf_trace_buf_submit() uprobes/tracing: Change create_trace_uprobe() to support uretprobes uprobes/tracing: Make seq_printf() code uretprobe-friendly uprobes/tracing: Make register_uprobe_event() paths uretprobe-friendly uprobes/tracing: Make uprobe_{trace,perf}_print() uretprobe-friendly uprobes/tracing: Introduce is_ret_probe() and uretprobe_dispatcher() uprobes/tracing: Introduce uprobe_{trace,perf}_print() helpers uprobes/tracing: Generalize struct uprobe_trace_entry_head uprobes/tracing: Kill the pointless local_save_flags/preempt_count calls uprobes/tracing: Kill the pointless seq_print_ip_sym() call uprobes/tracing: Kill the pointless task_pt_regs() calls ...
Diffstat (limited to 'kernel/trace')
-rw-r--r--kernel/trace/trace.h5
-rw-r--r--kernel/trace/trace_uprobe.c203
2 files changed, 146 insertions, 62 deletions
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 9e014582e763..711ca7d3e7f1 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -109,11 +109,6 @@ struct kretprobe_trace_entry_head {
unsigned long ret_ip;
};
-struct uprobe_trace_entry_head {
- struct trace_entry ent;
- unsigned long ip;
-};
-
/*
* trace_flag_type is an enumeration that holds different
* states when a trace occurs. These are:
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 8dad2a92dee9..32494fb0ee64 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -28,6 +28,18 @@
#define UPROBE_EVENT_SYSTEM "uprobes"
+struct uprobe_trace_entry_head {
+ struct trace_entry ent;
+ unsigned long vaddr[];
+};
+
+#define SIZEOF_TRACE_ENTRY(is_return) \
+ (sizeof(struct uprobe_trace_entry_head) + \
+ sizeof(unsigned long) * (is_return ? 2 : 1))
+
+#define DATAOF_TRACE_ENTRY(entry, is_return) \
+ ((void*)(entry) + SIZEOF_TRACE_ENTRY(is_return))
+
struct trace_uprobe_filter {
rwlock_t rwlock;
int nr_systemwide;
@@ -64,6 +76,8 @@ static DEFINE_MUTEX(uprobe_lock);
static LIST_HEAD(uprobe_list);
static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs);
+static int uretprobe_dispatcher(struct uprobe_consumer *con,
+ unsigned long func, struct pt_regs *regs);
static inline void init_trace_uprobe_filter(struct trace_uprobe_filter *filter)
{
@@ -77,11 +91,16 @@ static inline bool uprobe_filter_is_empty(struct trace_uprobe_filter *filter)
return !filter->nr_systemwide && list_empty(&filter->perf_events);
}
+static inline bool is_ret_probe(struct trace_uprobe *tu)
+{
+ return tu->consumer.ret_handler != NULL;
+}
+
/*
* Allocate new trace_uprobe and initialize it (including uprobes).
*/
static struct trace_uprobe *
-alloc_trace_uprobe(const char *group, const char *event, int nargs)
+alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret)
{
struct trace_uprobe *tu;
@@ -106,6 +125,8 @@ alloc_trace_uprobe(const char *group, const char *event, int nargs)
INIT_LIST_HEAD(&tu->list);
tu->consumer.handler = uprobe_dispatcher;
+ if (is_ret)
+ tu->consumer.ret_handler = uretprobe_dispatcher;
init_trace_uprobe_filter(&tu->filter);
return tu;
@@ -180,7 +201,7 @@ end:
/*
* Argument syntax:
- * - Add uprobe: p[:[GRP/]EVENT] PATH:SYMBOL[+offs] [FETCHARGS]
+ * - Add uprobe: p|r[:[GRP/]EVENT] PATH:SYMBOL [FETCHARGS]
*
* - Remove uprobe: -:[GRP/]EVENT
*/
@@ -192,20 +213,23 @@ static int create_trace_uprobe(int argc, char **argv)
char buf[MAX_EVENT_NAME_LEN];
struct path path;
unsigned long offset;
- bool is_delete;
+ bool is_delete, is_return;
int i, ret;
inode = NULL;
ret = 0;
is_delete = false;
+ is_return = false;
event = NULL;
group = NULL;
/* argc must be >= 1 */
if (argv[0][0] == '-')
is_delete = true;
+ else if (argv[0][0] == 'r')
+ is_return = true;
else if (argv[0][0] != 'p') {
- pr_info("Probe definition must be started with 'p' or '-'.\n");
+ pr_info("Probe definition must be started with 'p', 'r' or '-'.\n");
return -EINVAL;
}
@@ -303,7 +327,7 @@ static int create_trace_uprobe(int argc, char **argv)
kfree(tail);
}
- tu = alloc_trace_uprobe(group, event, argc);
+ tu = alloc_trace_uprobe(group, event, argc, is_return);
if (IS_ERR(tu)) {
pr_info("Failed to allocate trace_uprobe.(%d)\n", (int)PTR_ERR(tu));
ret = PTR_ERR(tu);
@@ -414,9 +438,10 @@ static void probes_seq_stop(struct seq_file *m, void *v)
static int probes_seq_show(struct seq_file *m, void *v)
{
struct trace_uprobe *tu = v;
+ char c = is_ret_probe(tu) ? 'r' : 'p';
int i;
- seq_printf(m, "p:%s/%s", tu->call.class->system, tu->call.name);
+ seq_printf(m, "%c:%s/%s", c, tu->call.class->system, tu->call.name);
seq_printf(m, " %s:0x%p", tu->filename, (void *)tu->offset);
for (i = 0; i < tu->nr_args; i++)
@@ -485,65 +510,81 @@ static const struct file_operations uprobe_profile_ops = {
.release = seq_release,
};
-/* uprobe handler */
-static int uprobe_trace_func(struct trace_uprobe *tu, struct pt_regs *regs)
+static void uprobe_trace_print(struct trace_uprobe *tu,
+ unsigned long func, struct pt_regs *regs)
{
struct uprobe_trace_entry_head *entry;
struct ring_buffer_event *event;
struct ring_buffer *buffer;
- u8 *data;
- int size, i, pc;
- unsigned long irq_flags;
+ void *data;
+ int size, i;
struct ftrace_event_call *call = &tu->call;
- local_save_flags(irq_flags);
- pc = preempt_count();
-
- size = sizeof(*entry) + tu->size;
-
+ size = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
event = trace_current_buffer_lock_reserve(&buffer, call->event.type,
- size, irq_flags, pc);
+ size + tu->size, 0, 0);
if (!event)
- return 0;
+ return;
entry = ring_buffer_event_data(event);
- entry->ip = instruction_pointer(task_pt_regs(current));
- data = (u8 *)&entry[1];
+ if (is_ret_probe(tu)) {
+ entry->vaddr[0] = func;
+ entry->vaddr[1] = instruction_pointer(regs);
+ data = DATAOF_TRACE_ENTRY(entry, true);
+ } else {
+ entry->vaddr[0] = instruction_pointer(regs);
+ data = DATAOF_TRACE_ENTRY(entry, false);
+ }
+
for (i = 0; i < tu->nr_args; i++)
call_fetch(&tu->args[i].fetch, regs, data + tu->args[i].offset);
if (!filter_current_check_discard(buffer, call, entry, event))
- trace_buffer_unlock_commit(buffer, event, irq_flags, pc);
+ trace_buffer_unlock_commit(buffer, event, 0, 0);
+}
+/* uprobe handler */
+static int uprobe_trace_func(struct trace_uprobe *tu, struct pt_regs *regs)
+{
+ if (!is_ret_probe(tu))
+ uprobe_trace_print(tu, 0, regs);
return 0;
}
+static void uretprobe_trace_func(struct trace_uprobe *tu, unsigned long func,
+ struct pt_regs *regs)
+{
+ uprobe_trace_print(tu, func, regs);
+}
+
/* Event entry printers */
static enum print_line_t
print_uprobe_event(struct trace_iterator *iter, int flags, struct trace_event *event)
{
- struct uprobe_trace_entry_head *field;
+ struct uprobe_trace_entry_head *entry;
struct trace_seq *s = &iter->seq;
struct trace_uprobe *tu;
u8 *data;
int i;
- field = (struct uprobe_trace_entry_head *)iter->ent;
+ entry = (struct uprobe_trace_entry_head *)iter->ent;
tu = container_of(event, struct trace_uprobe, call.event);
- if (!trace_seq_printf(s, "%s: (", tu->call.name))
- goto partial;
-
- if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET))
- goto partial;
-
- if (!trace_seq_puts(s, ")"))
- goto partial;
+ if (is_ret_probe(tu)) {
+ if (!trace_seq_printf(s, "%s: (0x%lx <- 0x%lx)", tu->call.name,
+ entry->vaddr[1], entry->vaddr[0]))
+ goto partial;
+ data = DATAOF_TRACE_ENTRY(entry, true);
+ } else {
+ if (!trace_seq_printf(s, "%s: (0x%lx)", tu->call.name,
+ entry->vaddr[0]))
+ goto partial;
+ data = DATAOF_TRACE_ENTRY(entry, false);
+ }
- data = (u8 *)&field[1];
for (i = 0; i < tu->nr_args; i++) {
if (!tu->args[i].type->print(s, tu->args[i].name,
- data + tu->args[i].offset, field))
+ data + tu->args[i].offset, entry))
goto partial;
}
@@ -595,16 +636,23 @@ static void probe_event_disable(struct trace_uprobe *tu, int flag)
static int uprobe_event_define_fields(struct ftrace_event_call *event_call)
{
- int ret, i;
+ int ret, i, size;
struct uprobe_trace_entry_head field;
- struct trace_uprobe *tu = (struct trace_uprobe *)event_call->data;
+ struct trace_uprobe *tu = event_call->data;
- DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0);
+ if (is_ret_probe(tu)) {
+ DEFINE_FIELD(unsigned long, vaddr[0], FIELD_STRING_FUNC, 0);
+ DEFINE_FIELD(unsigned long, vaddr[1], FIELD_STRING_RETIP, 0);
+ size = SIZEOF_TRACE_ENTRY(true);
+ } else {
+ DEFINE_FIELD(unsigned long, vaddr[0], FIELD_STRING_IP, 0);
+ size = SIZEOF_TRACE_ENTRY(false);
+ }
/* Set argument names as fields */
for (i = 0; i < tu->nr_args; i++) {
ret = trace_define_field(event_call, tu->args[i].type->fmttype,
tu->args[i].name,
- sizeof(field) + tu->args[i].offset,
+ size + tu->args[i].offset,
tu->args[i].type->size,
tu->args[i].type->is_signed,
FILTER_OTHER);
@@ -622,8 +670,13 @@ static int __set_print_fmt(struct trace_uprobe *tu, char *buf, int len)
int i;
int pos = 0;
- fmt = "(%lx)";
- arg = "REC->" FIELD_STRING_IP;
+ if (is_ret_probe(tu)) {
+ fmt = "(%lx <- %lx)";
+ arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP;
+ } else {
+ fmt = "(%lx)";
+ arg = "REC->" FIELD_STRING_IP;
+ }
/* When len=0, we just calculate the needed length */
@@ -752,49 +805,68 @@ static bool uprobe_perf_filter(struct uprobe_consumer *uc,
return ret;
}
-/* uprobe profile handler */
-static int uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs)
+static void uprobe_perf_print(struct trace_uprobe *tu,
+ unsigned long func, struct pt_regs *regs)
{
struct ftrace_event_call *call = &tu->call;
struct uprobe_trace_entry_head *entry;
struct hlist_head *head;
- u8 *data;
- int size, __size, i;
- int rctx;
+ void *data;
+ int size, rctx, i;
- if (!uprobe_perf_filter(&tu->consumer, 0, current->mm))
- return UPROBE_HANDLER_REMOVE;
-
- __size = sizeof(*entry) + tu->size;
- size = ALIGN(__size + sizeof(u32), sizeof(u64));
- size -= sizeof(u32);
+ size = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
+ size = ALIGN(size + tu->size + sizeof(u32), sizeof(u64)) - sizeof(u32);
if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, "profile buffer not large enough"))
- return 0;
+ return;
preempt_disable();
+ head = this_cpu_ptr(call->perf_events);
+ if (hlist_empty(head))
+ goto out;
entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx);
if (!entry)
goto out;
- entry->ip = instruction_pointer(task_pt_regs(current));
- data = (u8 *)&entry[1];
+ if (is_ret_probe(tu)) {
+ entry->vaddr[0] = func;
+ entry->vaddr[1] = instruction_pointer(regs);
+ data = DATAOF_TRACE_ENTRY(entry, true);
+ } else {
+ entry->vaddr[0] = instruction_pointer(regs);
+ data = DATAOF_TRACE_ENTRY(entry, false);
+ }
+
for (i = 0; i < tu->nr_args; i++)
call_fetch(&tu->args[i].fetch, regs, data + tu->args[i].offset);
- head = this_cpu_ptr(call->perf_events);
- perf_trace_buf_submit(entry, size, rctx, entry->ip, 1, regs, head, NULL);
-
+ perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL);
out:
preempt_enable();
+}
+
+/* uprobe profile handler */
+static int uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs)
+{
+ if (!uprobe_perf_filter(&tu->consumer, 0, current->mm))
+ return UPROBE_HANDLER_REMOVE;
+
+ if (!is_ret_probe(tu))
+ uprobe_perf_print(tu, 0, regs);
return 0;
}
+
+static void uretprobe_perf_func(struct trace_uprobe *tu, unsigned long func,
+ struct pt_regs *regs)
+{
+ uprobe_perf_print(tu, func, regs);
+}
#endif /* CONFIG_PERF_EVENTS */
static
int trace_uprobe_register(struct ftrace_event_call *event, enum trace_reg type, void *data)
{
- struct trace_uprobe *tu = (struct trace_uprobe *)event->data;
+ struct trace_uprobe *tu = event->data;
switch (type) {
case TRACE_REG_REGISTER:
@@ -843,6 +915,23 @@ static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs)
return ret;
}
+static int uretprobe_dispatcher(struct uprobe_consumer *con,
+ unsigned long func, struct pt_regs *regs)
+{
+ struct trace_uprobe *tu;
+
+ tu = container_of(con, struct trace_uprobe, consumer);
+
+ if (tu->flags & TP_FLAG_TRACE)
+ uretprobe_trace_func(tu, func, regs);
+
+#ifdef CONFIG_PERF_EVENTS
+ if (tu->flags & TP_FLAG_PROFILE)
+ uretprobe_perf_func(tu, func, regs);
+#endif
+ return 0;
+}
+
static struct trace_event_functions uprobe_funcs = {
.trace = print_uprobe_event
};