perf, bpf: Add BPF support to all perf_event types

Allow BPF_PROG_TYPE_PERF_EVENT program types to attach to all
perf_event types, including HW_CACHE, RAW, and dynamic pmu events.
Only tracepoint/kprobe events are treated differently which require
BPF_PROG_TYPE_TRACEPOINT/BPF_PROG_TYPE_KPROBE program types accordingly.

Also add support for reading all event counters using
bpf_perf_event_read() helper.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 7 insertions, 21 deletions

diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index 172dc8ee0e3b..ecb43542246e 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -452,38 +452,24 @@ static void bpf_event_entry_free_rcu(struct bpf_event_entry *ee)
 static void *perf_event_fd_array_get_ptr(struct bpf_map *map,
                                          struct file *map_file, int fd)
 {
-        const struct perf_event_attr *attr;
         struct bpf_event_entry *ee;
         struct perf_event *event;
         struct file *perf_file;
+        u64 value;
 
         perf_file = perf_event_get(fd);
         if (IS_ERR(perf_file))
                 return perf_file;
 
+        ee = ERR_PTR(-EOPNOTSUPP);
         event = perf_file->private_data;
-        ee = ERR_PTR(-EINVAL);
-
-        attr = perf_event_attrs(event);
-        if (IS_ERR(attr) || attr->inherit)
+        if (perf_event_read_local(event, &value) == -EOPNOTSUPP)
                 goto err_out;
 
-        switch (attr->type) {
-        case PERF_TYPE_SOFTWARE:
-                if (attr->config != PERF_COUNT_SW_BPF_OUTPUT)
-                        goto err_out;
-                /* fall-through */
-        case PERF_TYPE_RAW:
-        case PERF_TYPE_HARDWARE:
-                ee = bpf_event_entry_gen(perf_file, map_file);
-                if (ee)
-                        return ee;
-                ee = ERR_PTR(-ENOMEM);
-                /* fall-through */
-        default:
-                break;
-        }
-
+        ee = bpf_event_entry_gen(perf_file, map_file);
+        if (ee)
+                return ee;
+        ee = ERR_PTR(-ENOMEM);
 err_out:
         fput(perf_file);
         return ee;