Fix cachestat on kernel 5.15.x (eBPF) (#11833)

5 files changed, 36 insertions, 16 deletions

diff --git a/collectors/ebpf.plugin/ebpf_mdflush.c b/collectors/ebpf.plugin/ebpf_mdflush.c
index e2420ec8ee..38980713f5 100644
--- a/collectors/ebpf.plugin/ebpf_mdflush.c
+++ b/collectors/ebpf.plugin/ebpf_mdflush.c
@@ -294,6 +294,13 @@ void *ebpf_mdflush_thread(void *ptr)
     ebpf_module_t *em = (ebpf_module_t *)ptr;
     em->maps = mdflush_maps;
 
+    char *md_flush_request = ebpf_find_symbol("md_flush_request");
+    if (!md_flush_request) {
+        em->enabled = CONFIG_BOOLEAN_NO;
+        error("Cannot monitor MD devices, because md is not loaded.");
+    }
+    freez(md_flush_request);
+
     if (!em->enabled) {
         goto endmdflush;
     }
diff --git a/libnetdata/ebpf/ebpf.c b/libnetdata/ebpf/ebpf.c
index 1ccaa7b417..3aef243a47 100644
--- a/libnetdata/ebpf/ebpf.c
+++ b/libnetdata/ebpf/ebpf.c
@@ -257,7 +257,9 @@ char *ebpf_kernel_suffix(int version, int isrh)
         else
             return "3.10";
     } else {
-        if (version >= NETDATA_EBPF_KERNEL_5_11)
+        if (version >= NETDATA_EBPF_KERNEL_5_15)
+            return "5.15";
+        else if (version >= NETDATA_EBPF_KERNEL_5_11)
             return "5.11";
         else if (version >= NETDATA_EBPF_KERNEL_5_10)
             return "5.10";
@@ -375,18 +377,21 @@ static struct bpf_link **ebpf_attach_programs(struct bpf_object *obj, size_t len
     struct bpf_link **links = callocz(length , sizeof(struct bpf_link *));
     size_t i = 0;
     struct bpf_program *prog;
+    ebpf_specify_name_t *w;
     bpf_object__for_each_program(prog, obj)
     {
-        links[i] = bpf_program__attach(prog);
-        if (libbpf_get_error(links[i]) && names) {
+        if (names) {
             const char *name = bpf_program__name(prog);
-            ebpf_specify_name_t *w = ebpf_find_names(names, name);
-            if (w) {
-                enum bpf_prog_type type = bpf_program__get_type(prog);
-                if (type == BPF_PROG_TYPE_KPROBE)
-                    links[i] = bpf_program__attach_kprobe(prog, w->retprobe, w->optional);
-            }
-        }
+            w = ebpf_find_names(names, name);
+        } else
+            w = NULL;
+
+        if (w) {
+            enum bpf_prog_type type = bpf_program__get_type(prog);
+            if (type == BPF_PROG_TYPE_KPROBE)
+                links[i] = bpf_program__attach_kprobe(prog, w->retprobe, w->optional);
+        } else
+            links[i] = bpf_program__attach(prog);
 
         if (libbpf_get_error(links[i])) {
             links[i] = NULL;
@@ -483,7 +488,7 @@ struct bpf_link **ebpf_load_program(char *plugins_dir, ebpf_module_t *em, char *
     return ebpf_attach_programs(*obj, count_programs, em->names);
 }
 
-static char *ebpf_update_name(char *search)
+char *ebpf_find_symbol(char *search)
 {
     char filename[FILENAME_MAX + 1];
     char *ret = NULL;
@@ -521,7 +526,7 @@ void ebpf_update_names(ebpf_specify_name_t *opt, ebpf_module_t *em)
     size_t i = 0;
     while (opt[i].program_name) {
         opt[i].retprobe = (mode == MODE_RETURN);
-        opt[i].optional = ebpf_update_name(opt[i].function_to_attach);
+        opt[i].optional = ebpf_find_symbol(opt[i].function_to_attach);
 
         i++;
     }
diff --git a/libnetdata/ebpf/ebpf.h b/libnetdata/ebpf/ebpf.h
index 73128f529b..1da28d4cb3 100644
--- a/libnetdata/ebpf/ebpf.h
+++ b/libnetdata/ebpf/ebpf.h
@@ -46,6 +46,13 @@
 #define NETDATA_RH_8 2048
 
 /**
+ *  Kernel 5.15
+ *
+ *  331520 = 5*65536 + 15*256
+ */
+#define NETDATA_EBPF_KERNEL_5_15 331520
+
+/**
  *  Kernel 5.11
  *
  *  330240 = 5*65536 + 11*256
@@ -182,6 +189,7 @@ extern void ebpf_mount_config_name(char *filename, size_t length, char *path, co
 extern int ebpf_load_config(struct config *config, char *filename);
 extern void ebpf_update_module(ebpf_module_t *em);
 extern void ebpf_update_names(ebpf_specify_name_t *opt, ebpf_module_t *em);
+extern char *ebpf_find_symbol(char *search);
 extern void ebpf_load_addresses(ebpf_addresses_t *fa, int fd);
 extern void ebpf_fill_algorithms(int *algorithms, size_t length, int algorithm);
 extern char **ebpf_fill_histogram_dimension(size_t maximum);
diff --git a/packaging/ebpf.checksums b/packaging/ebpf.checksums
index 8ecbc9ce16..d98e99b0a8 100644
--- a/packaging/ebpf.checksums
+++ b/packaging/ebpf.checksums
@@ -1,3 +1,3 @@
-7ffd13d0f32df93bc7868a7cf040e75c40a9e041f6bb7f4a591cc6ce71b1cf72  netdata-kernel-collector-glibc-v0.8.6.tar.xz
-05c10d57252941b7f6dbb8a726a243416942c58738015014dd764b4bcb0c2f9c  netdata-kernel-collector-musl-v0.8.6.tar.xz
-2a607729a9093538624a94dfdbf2a3660eb4eb199f86962d38806d8e1e420a71  netdata-kernel-collector-static-v0.8.6.tar.xz
+44f21082c348b81f73034a986904207ee050379d51d6a6733a71323f2d36c8dd  netdata-kernel-collector-glibc-v0.9.0.tar.xz
+9589070de6b7fe29fb0ea8f23394625c2887ddf3007bca9e65cfdb11ce41a7f7  netdata-kernel-collector-musl-v0.9.0.tar.xz
+f39c5c97f10d08ce72551a64aef8f9264346608e7d215afc910a5fe2158db868  netdata-kernel-collector-static-v0.9.0.tar.xz
diff --git a/packaging/ebpf.version b/packaging/ebpf.version
index 85c3002dca..f979adec64 100644
--- a/packaging/ebpf.version
+++ b/packaging/ebpf.version
@@ -1 +1 @@
-v0.8.6
+v0.9.0