[PATCH v5 10/14] tools/xenstore: switch transaction accounting to generic accounting

[Juergen Gross <jgross@xxxxxxxx>]

As transaction accounting is active for unprivileged domains only, it
can easily be added to the generic per-domain accounting.

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
---
V5:
- use list_empty(&conn->transaction_list) for detection of "no
  transaction active" (Julien Grall)
---
 tools/xenstore/xenstored_core.c        |  3 +--
 tools/xenstore/xenstored_core.h        |  1 -
 tools/xenstore/xenstored_domain.c      | 21 ++++++++++++++++++---
 tools/xenstore/xenstored_domain.h      |  4 ++++
 tools/xenstore/xenstored_transaction.c | 14 ++++++--------
 5 files changed, 29 insertions(+), 14 deletions(-)

diff --git a/tools/xenstore/xenstored_core.c b/tools/xenstore/xenstored_core.c
index 3caf9e45dc..c98d30561f 100644
--- a/tools/xenstore/xenstored_core.c
+++ b/tools/xenstore/xenstored_core.c
@@ -2087,7 +2087,7 @@ static void consider_message(struct connection *conn)
         * stalled. This will ignore new requests until Live-Update happened
         * or it was aborted.
         */
-       if (lu_is_pending() && conn->transaction_started == 0 &&
+       if (lu_is_pending() && list_empty(&conn->transaction_list) &&
            conn->in->hdr.msg.type == XS_TRANSACTION_START) {
                trace("Delaying transaction start for connection %p req_id 
%u\n",
                      conn, conn->in->hdr.msg.req_id);
@@ -2194,7 +2194,6 @@ struct connection *new_connection(const struct 
interface_funcs *funcs)
        new->funcs = funcs;
        new->is_ignored = false;
        new->is_stalled = false;
-       new->transaction_started = 0;
        INIT_LIST_HEAD(&new->out_list);
        INIT_LIST_HEAD(&new->acc_list);
        INIT_LIST_HEAD(&new->ref_list);
diff --git a/tools/xenstore/xenstored_core.h b/tools/xenstore/xenstored_core.h
index 5a11dc1231..3564d85d7d 100644
--- a/tools/xenstore/xenstored_core.h
+++ b/tools/xenstore/xenstored_core.h
@@ -151,7 +151,6 @@ struct connection
        /* List of in-progress transactions. */
        struct list_head transaction_list;
        uint32_t next_transaction_id;
-       unsigned int transaction_started;
        time_t ta_start_time;
 
        /* List of delayed requests. */
diff --git a/tools/xenstore/xenstored_domain.c 
b/tools/xenstore/xenstored_domain.c
index 03825ca24b..25c6d20036 100644
--- a/tools/xenstore/xenstored_domain.c
+++ b/tools/xenstore/xenstored_domain.c
@@ -417,12 +417,10 @@ int domain_get_quota(const void *ctx, struct connection 
*conn,
 {
        struct domain *d = find_domain_struct(domid);
        char *resp;
-       int ta;
 
        if (!d)
                return ENOENT;
 
-       ta = d->conn ? d->conn->transaction_started : 0;
        resp = talloc_asprintf(ctx, "Domain %u:\n", domid);
        if (!resp)
                return ENOMEM;
@@ -433,7 +431,7 @@ int domain_get_quota(const void *ctx, struct connection 
*conn,
 
        ent(nodes, d->acc[ACC_NODES]);
        ent(watches, d->acc[ACC_WATCH]);
-       ent(transactions, ta);
+       ent(transactions, d->acc[ACC_TRANS]);
        ent(outstanding, d->acc[ACC_OUTST]);
        ent(memory, d->acc[ACC_MEM]);
 
@@ -1298,6 +1296,23 @@ void domain_outstanding_dec(struct connection *conn, 
unsigned int domid)
        domain_acc_add(conn, domid, ACC_OUTST, -1, true);
 }
 
+void domain_transaction_inc(struct connection *conn)
+{
+       domain_acc_add(conn, conn->id, ACC_TRANS, 1, true);
+}
+
+void domain_transaction_dec(struct connection *conn)
+{
+       domain_acc_add(conn, conn->id, ACC_TRANS, -1, true);
+}
+
+unsigned int domain_transaction_get(struct connection *conn)
+{
+       return (domain_is_unprivileged(conn))
+               ? domain_acc_add(conn, conn->id, ACC_TRANS, 0, true)
+               : 0;
+}
+
 static wrl_creditt wrl_config_writecost      = WRL_FACTOR;
 static wrl_creditt wrl_config_rate           = WRL_RATE   * WRL_FACTOR;
 static wrl_creditt wrl_config_dburst         = WRL_DBURST * WRL_FACTOR;
diff --git a/tools/xenstore/xenstored_domain.h 
b/tools/xenstore/xenstored_domain.h
index 086133407b..01b6f1861b 100644
--- a/tools/xenstore/xenstored_domain.h
+++ b/tools/xenstore/xenstored_domain.h
@@ -32,6 +32,7 @@ enum accitem {
        ACC_WATCH = ACC_TR_N,
        ACC_OUTST,
        ACC_MEM,
+       ACC_TRANS,
        ACC_N,                  /* Number of elements per domain. */
 };
 
@@ -113,6 +114,9 @@ void domain_watch_dec(struct connection *conn);
 int domain_watch(struct connection *conn);
 void domain_outstanding_inc(struct connection *conn);
 void domain_outstanding_dec(struct connection *conn, unsigned int domid);
+void domain_transaction_inc(struct connection *conn);
+void domain_transaction_dec(struct connection *conn);
+unsigned int domain_transaction_get(struct connection *conn);
 int domain_get_quota(const void *ctx, struct connection *conn,
                     unsigned int domid);
 
diff --git a/tools/xenstore/xenstored_transaction.c 
b/tools/xenstore/xenstored_transaction.c
index 11c8bcec84..b9e9d76a1f 100644
--- a/tools/xenstore/xenstored_transaction.c
+++ b/tools/xenstore/xenstored_transaction.c
@@ -479,8 +479,7 @@ int do_transaction_start(const void *ctx, struct connection 
*conn,
        if (conn->transaction)
                return EBUSY;
 
-       if (domain_is_unprivileged(conn) &&
-           conn->transaction_started > quota_max_transaction)
+       if (domain_transaction_get(conn) > quota_max_transaction)
                return ENOSPC;
 
        /* Attach transaction to ctx for autofree until it's complete */
@@ -502,12 +501,12 @@ int do_transaction_start(const void *ctx, struct 
connection *conn,
        } while (!IS_ERR(exists));
 
        /* Now we own it. */
+       if (list_empty(&conn->transaction_list))
+               conn->ta_start_time = time(NULL);
        list_add_tail(&trans->list, &conn->transaction_list);
        talloc_steal(conn, trans);
        talloc_set_destructor(trans, destroy_transaction);
-       if (!conn->transaction_started)
-               conn->ta_start_time = time(NULL);
-       conn->transaction_started++;
+       domain_transaction_inc(conn);
        wrl_ntransactions++;
 
        snprintf(id_str, sizeof(id_str), "%u", trans->id);
@@ -533,8 +532,8 @@ int do_transaction_end(const void *ctx, struct connection 
*conn,
 
        conn->transaction = NULL;
        list_del(&trans->list);
-       conn->transaction_started--;
-       if (!conn->transaction_started)
+       domain_transaction_dec(conn);
+       if (list_empty(&conn->transaction_list))
                conn->ta_start_time = 0;
 
        chk_quota = trans->node_created && domain_is_unprivileged(conn);
@@ -588,7 +587,6 @@ void conn_delete_all_transactions(struct connection *conn)
 
        assert(conn->transaction == NULL);
 
-       conn->transaction_started = 0;
        conn->ta_start_time = 0;
 }
 
-- 
2.35.3