[PATCH 05/12] tracing/uprobes: Convert to struct trace_probe

Namhyung Kim
2013-07-03T12:35:56Z

Convert struct trace_uprobe to make use of the common trace_probe
structure.

Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
kernel/trace/trace_uprobe.c | 151 ++++++++++++++++++++++----------------------
1 file changed, 75 insertions(+), 76 deletions(-)

diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 32494fb0ee64..20c35e2a2339 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -51,22 +51,17 @@ struct trace_uprobe_filter {
*/
struct trace_uprobe {
struct list_head list;
- struct ftrace_event_class class;
- struct ftrace_event_call call;
struct trace_uprobe_filter filter;
struct uprobe_consumer consumer;
struct inode *inode;
char *filename;
unsigned long offset;
unsigned long nhit;
- unsigned int flags; /* For TP_FLAG_* */
- ssize_t size; /* trace entry size */
- unsigned int nr_args;
- struct probe_arg args[];
+ struct trace_probe p;
};

-#define SIZEOF_TRACE_UPROBE(n) \
- (offsetof(struct trace_uprobe, args) + \
+#define SIZEOF_TRACE_UPROBE(n) \
+ (offsetof(struct trace_uprobe, p.args) + \
(sizeof(struct probe_arg) * (n)))

static int register_uprobe_event(struct trace_uprobe *tu);
@@ -114,13 +109,13 @@ alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret)
if (!tu)
return ERR_PTR(-ENOMEM);

- tu->call.class = &tu->class;
- tu->call.name = kstrdup(event, GFP_KERNEL);
- if (!tu->call.name)
+ tu->p.call.class = &tu->p.class;
+ tu->p.call.name = kstrdup(event, GFP_KERNEL);
+ if (!tu->p.call.name)
goto error;

- tu->class.system = kstrdup(group, GFP_KERNEL);
- if (!tu->class.system)
+ tu->p.class.system = kstrdup(group, GFP_KERNEL);
+ if (!tu->p.class.system)
goto error;

INIT_LIST_HEAD(&tu->list);
@@ -131,7 +126,7 @@ alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret)
return tu;

error:
- kfree(tu->call.name);
+ kfree(tu->p.call.name);
kfree(tu);

return ERR_PTR(-ENOMEM);
@@ -141,12 +136,12 @@ static void free_trace_uprobe(struct trace_uprobe *tu)
{
int i;

- for (i = 0; i < tu->nr_args; i++)
- traceprobe_free_probe_arg(&tu->args[i]);
+ for (i = 0; i < tu->p.nr_args; i++)
+ traceprobe_free_probe_arg(&tu->p.args[i]);

iput(tu->inode);
- kfree(tu->call.class->system);
- kfree(tu->call.name);
+ kfree(tu->p.call.class->system);
+ kfree(tu->p.call.name);
kfree(tu->filename);
kfree(tu);
}
@@ -156,8 +151,8 @@ static struct trace_uprobe *find_probe_event(const char *event, const char *grou
struct trace_uprobe *tu;

list_for_each_entry(tu, &uprobe_list, list)
- if (strcmp(tu->call.name, event) == 0 &&
- strcmp(tu->call.class->system, group) == 0)
+ if (strcmp(tu->p.call.name, event) == 0 &&
+ strcmp(tu->p.call.class->system, group) == 0)
return tu;

return NULL;
@@ -180,7 +175,7 @@ static int register_trace_uprobe(struct trace_uprobe *tu)
mutex_lock(&uprobe_lock);

/* register as an event */
- old_tp = find_probe_event(tu->call.name, tu->call.class->system);
+ old_tp = find_probe_event(tu->p.call.name, tu->p.call.class->system);
if (old_tp)
/* delete old event */
unregister_trace_uprobe(old_tp);
@@ -346,34 +341,36 @@ static int create_trace_uprobe(int argc, char **argv)
/* parse arguments */
ret = 0;
for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
+ struct probe_arg *parg = &tu->p.args[i];
+
/* Increment count for freeing args in error case */
- tu->nr_args++;
+ tu->p.nr_args++;

/* Parse argument name */
arg = strchr(argv[i], '=');
if (arg) {
*arg++ = '\0';
- tu->args[i].name = kstrdup(argv[i], GFP_KERNEL);
+ parg->name = kstrdup(argv[i], GFP_KERNEL);
} else {
arg = argv[i];
/* If argument name is omitted, set "argN" */
snprintf(buf, MAX_EVENT_NAME_LEN, "arg%d", i + 1);
- tu->args[i].name = kstrdup(buf, GFP_KERNEL);
+ parg->name = kstrdup(buf, GFP_KERNEL);
}

- if (!tu->args[i].name) {
+ if (!parg->name) {
pr_info("Failed to allocate argument[%d] name.\n", i);
ret = -ENOMEM;
goto error;
}

- if (!is_good_name(tu->args[i].name)) {
- pr_info("Invalid argument[%d] name: %s\n", i, tu->args[i].name);
+ if (!is_good_name(parg->name)) {
+ pr_info("Invalid argument[%d] name: %s\n", i, parg->name);
ret = -EINVAL;
goto error;
}

- if (traceprobe_conflict_field_name(tu->args[i].name, tu->args, i)) {
+ if (traceprobe_conflict_field_name(parg->name, tu->p.args, i)) {
pr_info("Argument[%d] name '%s' conflicts with "
"another field.\n", i, argv[i]);
ret = -EINVAL;
@@ -381,7 +378,8 @@ static int create_trace_uprobe(int argc, char **argv)
}

/* Parse fetch argument */
- ret = traceprobe_parse_probe_arg(arg, &tu->size, &tu->args[i], false, false);
+ ret = traceprobe_parse_probe_arg(arg, &tu->p.size, parg,
+ false, false);
if (ret) {
pr_info("Parse error at argument[%d]. (%d)\n", i, ret);
goto error;
@@ -441,11 +439,11 @@ static int probes_seq_show(struct seq_file *m, void *v)
char c = is_ret_probe(tu) ? 'r' : 'p';
int i;

- seq_printf(m, "%c:%s/%s", c, tu->call.class->system, tu->call.name);
+ seq_printf(m, "%c:%s/%s", c, tu->p.call.class->system, tu->p.call.name);
seq_printf(m, " %s:0x%p", tu->filename, (void *)tu->offset);

- for (i = 0; i < tu->nr_args; i++)
- seq_printf(m, " %s=%s", tu->args[i].name, tu->args[i].comm);
+ for (i = 0; i < tu->p.nr_args; i++)
+ seq_printf(m, " %s=%s", tu->p.args[i].name, tu->p.args[i].comm);

seq_printf(m, "\n");
return 0;
@@ -486,7 +484,7 @@ static int probes_profile_seq_show(struct seq_file *m, void *v)
{
struct trace_uprobe *tu = v;

- seq_printf(m, " %s %-44s %15lu\n", tu->filename, tu->call.name, tu->nhit);
+ seq_printf(m, " %s %-44s %15lu\n", tu->filename, tu->p.call.name, tu->nhit);
return 0;
}

@@ -518,11 +516,11 @@ static void uprobe_trace_print(struct trace_uprobe *tu,
struct ring_buffer *buffer;
void *data;
int size, i;
- struct ftrace_event_call *call = &tu->call;
+ struct ftrace_event_call *call = &tu->p.call;

size = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
event = trace_current_buffer_lock_reserve(&buffer, call->event.type,
- size + tu->size, 0, 0);
+ size + tu->p.size, 0, 0);
if (!event)
return;

@@ -536,8 +534,10 @@ static void uprobe_trace_print(struct trace_uprobe *tu,
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);
+ for (i = 0; i < tu->p.nr_args; i++) {
+ call_fetch(&tu->p.args[i].fetch, regs,
+ data + tu->p.args[i].offset);
+ }

if (!filter_current_check_discard(buffer, call, entry, event))
trace_buffer_unlock_commit(buffer, event, 0, 0);
@@ -568,23 +568,24 @@ print_uprobe_event(struct trace_iterator *iter, int flags, struct trace_event *e
int i;

entry = (struct uprobe_trace_entry_head *)iter->ent;
- tu = container_of(event, struct trace_uprobe, call.event);
+ tu = container_of(event, struct trace_uprobe, p.call.event);

if (is_ret_probe(tu)) {
- if (!trace_seq_printf(s, "%s: (0x%lx <- 0x%lx)", tu->call.name,
+ if (!trace_seq_printf(s, "%s: (0x%lx <- 0x%lx)", tu->p.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,
+ if (!trace_seq_printf(s, "%s: (0x%lx)", tu->p.call.name,
entry->vaddr[0]))
goto partial;
data = DATAOF_TRACE_ENTRY(entry, false);
}

- for (i = 0; i < tu->nr_args; i++) {
- if (!tu->args[i].type->print(s, tu->args[i].name,
- data + tu->args[i].offset, entry))
+ for (i = 0; i < tu->p.nr_args; i++) {
+ struct probe_arg *parg = &tu->p.args[i];
+
+ if (!parg->type->print(s, parg->name, data + parg->offset, entry))
goto partial;
}

@@ -595,11 +596,6 @@ partial:
return TRACE_TYPE_PARTIAL_LINE;
}

-static inline bool is_trace_uprobe_enabled(struct trace_uprobe *tu)
-{
- return tu->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE);
-}
-
typedef bool (*filter_func_t)(struct uprobe_consumer *self,
enum uprobe_filter_ctx ctx,
struct mm_struct *mm);
@@ -609,29 +605,29 @@ probe_event_enable(struct trace_uprobe *tu, int flag, filter_func_t filter)
{
int ret = 0;

- if (is_trace_uprobe_enabled(tu))
+ if (trace_probe_is_enabled(&tu->p))
return -EINTR;

WARN_ON(!uprobe_filter_is_empty(&tu->filter));

- tu->flags |= flag;
+ tu->p.flags |= flag;
tu->consumer.filter = filter;
ret = uprobe_register(tu->inode, tu->offset, &tu->consumer);
if (ret)
- tu->flags &= ~flag;
+ tu->p.flags &= ~flag;

return ret;
}

static void probe_event_disable(struct trace_uprobe *tu, int flag)
{
- if (!is_trace_uprobe_enabled(tu))
+ if (!trace_probe_is_enabled(&tu->p))
return;

WARN_ON(!uprobe_filter_is_empty(&tu->filter));

uprobe_unregister(tu->inode, tu->offset, &tu->consumer);
- tu->flags &= ~flag;
+ tu->p.flags &= ~flag;
}

static int uprobe_event_define_fields(struct ftrace_event_call *event_call)
@@ -649,12 +645,12 @@ static int uprobe_event_define_fields(struct ftrace_event_call *event_call)
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,
- size + tu->args[i].offset,
- tu->args[i].type->size,
- tu->args[i].type->is_signed,
+ for (i = 0; i < tu->p.nr_args; i++) {
+ struct probe_arg *parg = &tu->p.args[i];
+
+ ret = trace_define_field(event_call, parg->type->fmttype,
+ parg->name, size + parg->offset,
+ parg->type->size, parg->type->is_signed,
FILTER_OTHER);

if (ret)
@@ -682,16 +678,16 @@ static int __set_print_fmt(struct trace_uprobe *tu, char *buf, int len)

pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt);

- for (i = 0; i < tu->nr_args; i++) {
+ for (i = 0; i < tu->p.nr_args; i++) {
pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%s",
- tu->args[i].name, tu->args[i].type->fmt);
+ tu->p.args[i].name, tu->p.args[i].type->fmt);
}

pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg);

- for (i = 0; i < tu->nr_args; i++) {
+ for (i = 0; i < tu->p.nr_args; i++) {
pos += snprintf(buf + pos, LEN_OR_ZERO, ", REC->%s",
- tu->args[i].name);
+ tu->p.args[i].name);
}

return pos; /* return the length of print_fmt */
@@ -711,7 +707,7 @@ static int set_print_fmt(struct trace_uprobe *tu)

/* Second: actually write the @print_fmt */
__set_print_fmt(tu, print_fmt, len + 1);
- tu->call.print_fmt = print_fmt;
+ tu->p.call.print_fmt = print_fmt;

return 0;
}
@@ -808,14 +804,14 @@ static bool uprobe_perf_filter(struct uprobe_consumer *uc,
static void uprobe_perf_print(struct trace_uprobe *tu,
unsigned long func, struct pt_regs *regs)
{
- struct ftrace_event_call *call = &tu->call;
+ struct ftrace_event_call *call = &tu->p.call;
struct uprobe_trace_entry_head *entry;
struct hlist_head *head;
void *data;
int size, rctx, i;

size = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
- size = ALIGN(size + tu->size + sizeof(u32), sizeof(u64)) - sizeof(u32);
+ size = ALIGN(size + tu->p.size + sizeof(u32), sizeof(u64)) - sizeof(u32);
if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, "profile buffer not large enough"))
return;

@@ -837,8 +833,11 @@ static void uprobe_perf_print(struct trace_uprobe *tu,
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);
+ for (i = 0; i < tu->p.nr_args; i++) {
+ struct probe_arg *parg = &tu->p.args[i];
+
+ call_fetch(&parg->fetch, regs, data + parg->offset);
+ }

perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL);
out:
@@ -905,11 +904,11 @@ static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs)
tu = container_of(con, struct trace_uprobe, consumer);
tu->nhit++;

- if (tu->flags & TP_FLAG_TRACE)
+ if (tu->p.flags & TP_FLAG_TRACE)
ret |= uprobe_trace_func(tu, regs);

#ifdef CONFIG_PERF_EVENTS
- if (tu->flags & TP_FLAG_PROFILE)
+ if (tu->p.flags & TP_FLAG_PROFILE)
ret |= uprobe_perf_func(tu, regs);
#endif
return ret;
@@ -922,11 +921,11 @@ static int uretprobe_dispatcher(struct uprobe_consumer *con,

tu = container_of(con, struct trace_uprobe, consumer);

- if (tu->flags & TP_FLAG_TRACE)
+ if (tu->p.flags & TP_FLAG_TRACE)
uretprobe_trace_func(tu, func, regs);

#ifdef CONFIG_PERF_EVENTS
- if (tu->flags & TP_FLAG_PROFILE)
+ if (tu->p.flags & TP_FLAG_PROFILE)
uretprobe_perf_func(tu, func, regs);
#endif
return 0;
@@ -938,7 +937,7 @@ static struct trace_event_functions uprobe_funcs = {

static int register_uprobe_event(struct trace_uprobe *tu)
{
- struct ftrace_event_call *call = &tu->call;
+ struct ftrace_event_call *call = &tu->p.call;
int ret;

/* Initialize ftrace_event_call */
@@ -971,9 +970,9 @@ static int register_uprobe_event(struct trace_uprobe *tu)
static void unregister_uprobe_event(struct trace_uprobe *tu)
{
/* tu->event is unregistered in trace_remove_event_call() */
- trace_remove_event_call(&tu->call);
- kfree(tu->call.print_fmt);
- tu->call.print_fmt = NULL;
+ trace_remove_event_call(&tu->p.call);
+ kfree(tu->p.call.print_fmt);
+ tu->p.call.print_fmt = NULL;
}

/* Make a trace interface for controling probe points */
--
1.7.11.7