Adding upstream version 6.10.3.upstream/6.10.3

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 63 insertions, 44 deletions

diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 9e46136245..c98e3b3386 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -854,6 +854,7 @@ static const struct file_operations uprobe_profile_ops = {
 struct uprobe_cpu_buffer {
 	struct mutex mutex;
 	void *buf;
+	int dsize;
 };
 static struct uprobe_cpu_buffer __percpu *uprobe_cpu_buffer;
 static int uprobe_buffer_refcnt;
@@ -940,12 +941,36 @@ static struct uprobe_cpu_buffer *uprobe_buffer_get(void)
 
 static void uprobe_buffer_put(struct uprobe_cpu_buffer *ucb)
 {
+	if (!ucb)
+		return;
 	mutex_unlock(&ucb->mutex);
 }
 
+static struct uprobe_cpu_buffer *prepare_uprobe_buffer(struct trace_uprobe *tu,
+						       struct pt_regs *regs,
+						       struct uprobe_cpu_buffer **ucbp)
+{
+	struct uprobe_cpu_buffer *ucb;
+	int dsize, esize;
+
+	if (*ucbp)
+		return *ucbp;
+
+	esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
+	dsize = __get_data_size(&tu->tp, regs, NULL);
+
+	ucb = uprobe_buffer_get();
+	ucb->dsize = tu->tp.size + dsize;
+
+	store_trace_args(ucb->buf, &tu->tp, regs, NULL, esize, dsize);
+
+	*ucbp = ucb;
+	return ucb;
+}
+
 static void __uprobe_trace_func(struct trace_uprobe *tu,
 				unsigned long func, struct pt_regs *regs,
-				struct uprobe_cpu_buffer *ucb, int dsize,
+				struct uprobe_cpu_buffer *ucb,
 				struct trace_event_file *trace_file)
 {
 	struct uprobe_trace_entry_head *entry;
@@ -956,14 +981,14 @@ static void __uprobe_trace_func(struct trace_uprobe *tu,
 
 	WARN_ON(call != trace_file->event_call);
 
-	if (WARN_ON_ONCE(tu->tp.size + dsize > PAGE_SIZE))
+	if (WARN_ON_ONCE(ucb->dsize > PAGE_SIZE))
 		return;
 
 	if (trace_trigger_soft_disabled(trace_file))
 		return;
 
 	esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
-	size = esize + tu->tp.size + dsize;
+	size = esize + ucb->dsize;
 	entry = trace_event_buffer_reserve(&fbuffer, trace_file, size);
 	if (!entry)
 		return;
@@ -977,23 +1002,26 @@ static void __uprobe_trace_func(struct trace_uprobe *tu,
 		data = DATAOF_TRACE_ENTRY(entry, false);
 	}
 
-	memcpy(data, ucb->buf, tu->tp.size + dsize);
+	memcpy(data, ucb->buf, ucb->dsize);
 
 	trace_event_buffer_commit(&fbuffer);
 }
 
 /* uprobe handler */
 static int uprobe_trace_func(struct trace_uprobe *tu, struct pt_regs *regs,
-			     struct uprobe_cpu_buffer *ucb, int dsize)
+			     struct uprobe_cpu_buffer **ucbp)
 {
 	struct event_file_link *link;
+	struct uprobe_cpu_buffer *ucb;
 
 	if (is_ret_probe(tu))
 		return 0;
 
+	ucb = prepare_uprobe_buffer(tu, regs, ucbp);
+
 	rcu_read_lock();
 	trace_probe_for_each_link_rcu(link, &tu->tp)
-		__uprobe_trace_func(tu, 0, regs, ucb, dsize, link->file);
+		__uprobe_trace_func(tu, 0, regs, ucb, link->file);
 	rcu_read_unlock();
 
 	return 0;
@@ -1001,13 +1029,16 @@ static int uprobe_trace_func(struct trace_uprobe *tu, struct pt_regs *regs,
 
 static void uretprobe_trace_func(struct trace_uprobe *tu, unsigned long func,
 				 struct pt_regs *regs,
-				 struct uprobe_cpu_buffer *ucb, int dsize)
+				 struct uprobe_cpu_buffer **ucbp)
 {
 	struct event_file_link *link;
+	struct uprobe_cpu_buffer *ucb;
+
+	ucb = prepare_uprobe_buffer(tu, regs, ucbp);
 
 	rcu_read_lock();
 	trace_probe_for_each_link_rcu(link, &tu->tp)
-		__uprobe_trace_func(tu, func, regs, ucb, dsize, link->file);
+		__uprobe_trace_func(tu, func, regs, ucb, link->file);
 	rcu_read_unlock();
 }
 
@@ -1199,9 +1230,6 @@ __uprobe_perf_filter(struct trace_uprobe_filter *filter, struct mm_struct *mm)
 {
 	struct perf_event *event;
 
-	if (filter->nr_systemwide)
-		return true;
-
 	list_for_each_entry(event, &filter->perf_events, hw.tp_list) {
 		if (event->hw.target->mm == mm)
 			return true;
@@ -1326,6 +1354,13 @@ static bool uprobe_perf_filter(struct uprobe_consumer *uc,
 	tu = container_of(uc, struct trace_uprobe, consumer);
 	filter = tu->tp.event->filter;
 
+	/*
+	 * speculative short-circuiting check to avoid unnecessarily taking
+	 * filter->rwlock below, if the uprobe has system-wide consumer
+	 */
+	if (READ_ONCE(filter->nr_systemwide))
+		return true;
+
 	read_lock(&filter->rwlock);
 	ret = __uprobe_perf_filter(filter, mm);
 	read_unlock(&filter->rwlock);
@@ -1335,10 +1370,11 @@ static bool uprobe_perf_filter(struct uprobe_consumer *uc,
 
 static void __uprobe_perf_func(struct trace_uprobe *tu,
 			       unsigned long func, struct pt_regs *regs,
-			       struct uprobe_cpu_buffer *ucb, int dsize)
+			       struct uprobe_cpu_buffer **ucbp)
 {
 	struct trace_event_call *call = trace_probe_event_call(&tu->tp);
 	struct uprobe_trace_entry_head *entry;
+	struct uprobe_cpu_buffer *ucb;
 	struct hlist_head *head;
 	void *data;
 	int size, esize;
@@ -1356,7 +1392,8 @@ static void __uprobe_perf_func(struct trace_uprobe *tu,
 
 	esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
 
-	size = esize + tu->tp.size + dsize;
+	ucb = prepare_uprobe_buffer(tu, regs, ucbp);
+	size = esize + ucb->dsize;
 	size = ALIGN(size + sizeof(u32), sizeof(u64)) - sizeof(u32);
 	if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, "profile buffer not large enough"))
 		return;
@@ -1379,13 +1416,10 @@ static void __uprobe_perf_func(struct trace_uprobe *tu,
 		data = DATAOF_TRACE_ENTRY(entry, false);
 	}
 
-	memcpy(data, ucb->buf, tu->tp.size + dsize);
-
-	if (size - esize > tu->tp.size + dsize) {
-		int len = tu->tp.size + dsize;
+	memcpy(data, ucb->buf, ucb->dsize);
 
-		memset(data + len, 0, size - esize - len);
-	}
+	if (size - esize > ucb->dsize)
+		memset(data + ucb->dsize, 0, size - esize - ucb->dsize);
 
 	perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs,
 			      head, NULL);
@@ -1395,21 +1429,21 @@ static void __uprobe_perf_func(struct trace_uprobe *tu,
 
 /* uprobe profile handler */
 static int uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs,
-			    struct uprobe_cpu_buffer *ucb, int dsize)
+			    struct uprobe_cpu_buffer **ucbp)
 {
 	if (!uprobe_perf_filter(&tu->consumer, 0, current->mm))
 		return UPROBE_HANDLER_REMOVE;
 
 	if (!is_ret_probe(tu))
-		__uprobe_perf_func(tu, 0, regs, ucb, dsize);
+		__uprobe_perf_func(tu, 0, regs, ucbp);
 	return 0;
 }
 
 static void uretprobe_perf_func(struct trace_uprobe *tu, unsigned long func,
 				struct pt_regs *regs,
-				struct uprobe_cpu_buffer *ucb, int dsize)
+				struct uprobe_cpu_buffer **ucbp)
 {
-	__uprobe_perf_func(tu, func, regs, ucb, dsize);
+	__uprobe_perf_func(tu, func, regs, ucbp);
 }
 
 int bpf_get_uprobe_info(const struct perf_event *event, u32 *fd_type,
@@ -1474,11 +1508,9 @@ static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs)
 {
 	struct trace_uprobe *tu;
 	struct uprobe_dispatch_data udd;
-	struct uprobe_cpu_buffer *ucb;
-	int dsize, esize;
+	struct uprobe_cpu_buffer *ucb = NULL;
 	int ret = 0;
 
-
 	tu = container_of(con, struct trace_uprobe, consumer);
 	tu->nhit++;
 
@@ -1490,18 +1522,12 @@ static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs)
 	if (WARN_ON_ONCE(!uprobe_cpu_buffer))
 		return 0;
 
-	dsize = __get_data_size(&tu->tp, regs, NULL);
-	esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
-
-	ucb = uprobe_buffer_get();
-	store_trace_args(ucb->buf, &tu->tp, regs, NULL, esize, dsize);
-
 	if (trace_probe_test_flag(&tu->tp, TP_FLAG_TRACE))
-		ret |= uprobe_trace_func(tu, regs, ucb, dsize);
+		ret |= uprobe_trace_func(tu, regs, &ucb);
 
 #ifdef CONFIG_PERF_EVENTS
 	if (trace_probe_test_flag(&tu->tp, TP_FLAG_PROFILE))
-		ret |= uprobe_perf_func(tu, regs, ucb, dsize);
+		ret |= uprobe_perf_func(tu, regs, &ucb);
 #endif
 	uprobe_buffer_put(ucb);
 	return ret;
@@ -1512,8 +1538,7 @@ static int uretprobe_dispatcher(struct uprobe_consumer *con,
 {
 	struct trace_uprobe *tu;
 	struct uprobe_dispatch_data udd;
-	struct uprobe_cpu_buffer *ucb;
-	int dsize, esize;
+	struct uprobe_cpu_buffer *ucb = NULL;
 
 	tu = container_of(con, struct trace_uprobe, consumer);
 
@@ -1525,18 +1550,12 @@ static int uretprobe_dispatcher(struct uprobe_consumer *con,
 	if (WARN_ON_ONCE(!uprobe_cpu_buffer))
 		return 0;
 
-	dsize = __get_data_size(&tu->tp, regs, NULL);
-	esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
-
-	ucb = uprobe_buffer_get();
-	store_trace_args(ucb->buf, &tu->tp, regs, NULL, esize, dsize);
-
 	if (trace_probe_test_flag(&tu->tp, TP_FLAG_TRACE))
-		uretprobe_trace_func(tu, func, regs, ucb, dsize);
+		uretprobe_trace_func(tu, func, regs, &ucb);
 
 #ifdef CONFIG_PERF_EVENTS
 	if (trace_probe_test_flag(&tu->tp, TP_FLAG_PROFILE))
-		uretprobe_perf_func(tu, func, regs, ucb, dsize);
+		uretprobe_perf_func(tu, func, regs, &ucb);
 #endif
 	uprobe_buffer_put(ucb);
 	return 0;