DP: Add Generic DP Request Probes

Add the ability to analyze performance and monitor Data Provider
requests at a high-level, probes fire when a request is sent and when
a request is completed.

Request name, domain, target, method, and return code information
is passed as target variables to the systemtap probe tapsets which
can be used in systemtap scripts.

Resolves:
https://pagure.io/SSSD/sssd/issue/3061

Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>

4 files changed, 96 insertions, 0 deletions

diff --git a/src/providers/data_provider/dp_request.c b/src/providers/data_provider/dp_request.c
index 6c0a0b72d..a6bc020e0 100644
--- a/src/providers/data_provider/dp_request.c
+++ b/src/providers/data_provider/dp_request.c
@@ -27,6 +27,7 @@
 #include "providers/backend.h"
 #include "util/dlinklist.h"
 #include "util/util.h"
+#include "util/probes.h"
 
 struct dp_req {
     struct data_provider *provider;
@@ -309,6 +310,7 @@ struct tevent_req *dp_req_send(TALLOC_CTX *mem_ctx,
         goto immediately;
     }
 
+    PROBE(DP_REQ_SEND, domain, dp_req->name, target, method);
     state->dp_req = dp_req;
     if (_request_name != NULL) {
         request_name = talloc_strdup(mem_ctx, dp_req->name);
@@ -363,6 +365,9 @@ static void dp_req_done(struct tevent_req *subreq)
     talloc_zfree(subreq);
     state->dp_req->handler_req = NULL;
 
+    PROBE(DP_REQ_DONE, state->dp_req->name, state->dp_req->target,
+          state->dp_req->method, ret, sss_strerror(ret));
+
     DP_REQ_DEBUG(SSSDBG_TRACE_FUNC, state->dp_req->name,
                  "Request handler finished [%d]: %s", ret, sss_strerror(ret));
 
diff --git a/src/systemtap/sssd.stp.in b/src/systemtap/sssd.stp.in
index 199916383..25a68cd04 100644
--- a/src/systemtap/sssd.stp.in
+++ b/src/systemtap/sssd.stp.in
@@ -254,3 +254,21 @@ probe sdap_nested_group_process_recv = process("@libdir@/sssd/libsss_ldap_common
     probestr = sprintf("-> %s(orig_dn=[%s])",
                        $$name, orig_dn);
 }
+
+## Data Provider Request Probes
+probe dp_req_send = process("@libexecdir@/sssd/sssd_be").mark("dp_req_send")
+{
+    dp_req_domain = user_string($arg1, "NULL");
+    dp_req_name = user_string($arg2, "NULL");
+    dp_req_target = $arg3;
+    dp_req_method = $arg4;
+}
+
+probe dp_req_done = process("@libexecdir@/sssd/sssd_be").mark("dp_req_done")
+{
+    dp_req_name = user_string($arg1, "NULL");
+    dp_req_target = $arg2;
+    dp_req_method = $arg3;
+    dp_ret = $arg4;
+    dp_errorstr = user_string($arg5, "NULL");
+}
diff --git a/src/systemtap/sssd_functions.stp b/src/systemtap/sssd_functions.stp
index bad194ead..e249aac98 100644
--- a/src/systemtap/sssd_functions.stp
+++ b/src/systemtap/sssd_functions.stp
@@ -1,3 +1,13 @@
+// constants
+global TARGET_ID=0, TARGET_AUTH=1, TARGET_ACCESS=2, TARGET_CHPASS=3,
+       TARGET_SUDO=4, TARGET_AUTOFS=5, TARGET_SELINUX=6, TARGET_HOSTID=7,
+       TARGET_SUBDOMAINS=8, TARGET_SENTINEL=9
+
+global METHOD_CHECK_ONLINE=0, METHOD_ACCOUNT_HANDLER=1, METHOD_AUTH_HANDLER=2,
+       METHOD_ACCESS_HANDLER=3, METHOD_SELINUX_HANDLER=4, METHOD_SUDO_HANDLER=5,
+       METHOD_AUTOFS_HANDLER=6, METHOD_HOSTID_HANDLER=7, METHOD_DOMAINS_HANDLER=8,
+       METHOD_SENTINEL=9
+
 function acct_req_desc(entry_type)
 {
     if (entry_type == 0x0001) {
@@ -64,3 +74,61 @@ function sssd_acct_req_probestr(fc_name, entry_type, filter_type,
                        filter_value, extra_value)
     return probestr
 }
+
+function dp_target_str(target)
+{
+    if (target == TARGET_ID) {
+        str_target = "ID"
+    } else if (target == TARGET_AUTH) {
+        str_target = "AUTH"
+    } else if (target == TARGET_ACCESS) {
+        str_target = "ACCESS"
+    } else if (target == TARGET_CHPASS) {
+        str_target = "CHPASS"
+    } else if (target == TARGET_SUDO) {
+        str_target = "SUDO"
+    } else if (target == TARGET_AUTOFS) {
+        str_target = "AUTOFS"
+    } else if (target == TARGET_SELINUX) {
+        str_target = "SELINUX"
+    } else if (target == TARGET_HOSTID) {
+        str_target = "HOSTID"
+    } else if (target == TARGET_SUBDOMAINS) {
+        str_target = "SUBDOMAINS"
+    } else if (target == TARGET_SENTINEL) {
+        str_target = "TARGET_SENTINEL"
+    } else {
+        str_target = "UNKNOWN"
+    }
+
+    return str_target
+}
+
+function dp_method_str(method)
+{
+    if (method == METHOD_CHECK_ONLINE) {
+        str_method = "Check Online"
+    } else if (method == METHOD_ACCOUNT_HANDLER) {
+        str_method = "Account Handler"
+    } else if (method == METHOD_AUTH_HANDLER) {
+        str_method = "Auth Handler"
+    } else if (method == METHOD_ACCESS_HANDLER) {
+        str_method = "Access Handler"
+    } else if (method == METHOD_SELINUX_HANDLER) {
+        str_method = "SELinux Handler"
+    } else if (method == METHOD_SUDO_HANDLER) {
+        str_method = "Sudo Handler"
+    } else if (method == METHOD_AUTOFS_HANDLER) {
+        str_method = "Autofs Handler"
+    } else if (method == METHOD_HOSTID_HANDLER) {
+        str_method = "HostID Handler"
+    } else if (method == METHOD_DOMAINS_HANDLER) {
+        str_method = "Domains Handler"
+    } else if (method == METHOD_SENTINEL) {
+        str_method = "Method Sentinel"
+    } else {
+        str_method = "UNKNOWN"
+    }
+
+    return str_method
+}
diff --git a/src/systemtap/sssd_probes.d b/src/systemtap/sssd_probes.d
index 33339b415..c0d526871 100644
--- a/src/systemtap/sssd_probes.d
+++ b/src/systemtap/sssd_probes.d
@@ -65,4 +65,9 @@ provider sssd {
     probe sdap_nested_group_sysdb_search_groups_post();
     probe sdap_nested_group_populate_search_users_pre();
     probe sdap_nested_group_populate_search_users_post();
+
+    probe dp_req_send(const char *domain, const char *dp_req_name,
+                      int target, int method);
+    probe dp_req_done(const char *dp_req_name, int target, int method,
+                      int ret, const char *errorstr);
 }