2 files changed, 39 insertions, 14 deletions

diff --git a/samples/bpf/tracex3_kern.c b/samples/bpf/tracex3_kern.c
index bde6591cb20c..af235bd6615b 100644
--- a/samples/bpf/tracex3_kern.c
+++ b/samples/bpf/tracex3_kern.c
@@ -11,6 +11,12 @@
 #include <bpf/bpf_helpers.h>
 #include <bpf/bpf_tracing.h>
 
+struct start_key {
+	dev_t dev;
+	u32 _pad;
+	sector_t sector;
+};
+
 struct {
 	__uint(type, BPF_MAP_TYPE_HASH);
 	__type(key, long);
@@ -18,16 +24,17 @@ struct {
 	__uint(max_entries, 4096);
 } my_map SEC(".maps");
 
-/* kprobe is NOT a stable ABI. If kernel internals change this bpf+kprobe
- * example will no longer be meaningful
- */
-SEC("kprobe/blk_mq_start_request")
-int bpf_prog1(struct pt_regs *ctx)
+/* from /sys/kernel/tracing/events/block/block_io_start/format */
+SEC("tracepoint/block/block_io_start")
+int bpf_prog1(struct trace_event_raw_block_rq *ctx)
 {
-	long rq = PT_REGS_PARM1(ctx);
 	u64 val = bpf_ktime_get_ns();
+	struct start_key key = {
+		.dev = ctx->dev,
+		.sector = ctx->sector
+	};
 
-	bpf_map_update_elem(&my_map, &rq, &val, BPF_ANY);
+	bpf_map_update_elem(&my_map, &key, &val, BPF_ANY);
 	return 0;
 }
 
@@ -49,21 +56,26 @@ struct {
 	__uint(max_entries, SLOTS);
 } lat_map SEC(".maps");
 
-SEC("kprobe/__blk_account_io_done")
-int bpf_prog2(struct pt_regs *ctx)
+/* from /sys/kernel/tracing/events/block/block_io_done/format */
+SEC("tracepoint/block/block_io_done")
+int bpf_prog2(struct trace_event_raw_block_rq *ctx)
 {
-	long rq = PT_REGS_PARM1(ctx);
+	struct start_key key = {
+		.dev = ctx->dev,
+		.sector = ctx->sector
+	};
+
 	u64 *value, l, base;
 	u32 index;
 
-	value = bpf_map_lookup_elem(&my_map, &rq);
+	value = bpf_map_lookup_elem(&my_map, &key);
 	if (!value)
 		return 0;
 
 	u64 cur_time = bpf_ktime_get_ns();
 	u64 delta = cur_time - *value;
 
-	bpf_map_delete_elem(&my_map, &rq);
+	bpf_map_delete_elem(&my_map, &key);
 
 	/* the lines below are computing index = log10(delta)*10
 	 * using integer arithmetic
diff --git a/samples/bpf/tracex6_kern.c b/samples/bpf/tracex6_kern.c
index acad5712d8b4..fd602c2774b8 100644
--- a/samples/bpf/tracex6_kern.c
+++ b/samples/bpf/tracex6_kern.c
@@ -2,6 +2,8 @@
 #include <linux/version.h>
 #include <uapi/linux/bpf.h>
 #include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+#include <bpf/bpf_core_read.h>
 
 struct {
 	__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
@@ -45,13 +47,24 @@ int bpf_prog1(struct pt_regs *ctx)
 	return 0;
 }
 
-SEC("kprobe/htab_map_lookup_elem")
-int bpf_prog2(struct pt_regs *ctx)
+/*
+ * Since *_map_lookup_elem can't be expected to trigger bpf programs
+ * due to potential deadlocks (bpf_disable_instrumentation), this bpf
+ * program will be attached to bpf_map_copy_value (which is called
+ * from map_lookup_elem) and will only filter the hashtable type.
+ */
+SEC("kprobe/bpf_map_copy_value")
+int BPF_KPROBE(bpf_prog2, struct bpf_map *map)
 {
 	u32 key = bpf_get_smp_processor_id();
 	struct bpf_perf_event_value *val, buf;
+	enum bpf_map_type type;
 	int error;
 
+	type = BPF_CORE_READ(map, map_type);
+	if (type != BPF_MAP_TYPE_HASH)
+		return 0;
+
 	error = bpf_perf_event_read_value(&counters, key, &buf, sizeof(buf));
 	if (error)
 		return 0;