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From d94645f1eb00e2703aef57cac19df9e86c54d275 Mon Sep 17 00:00:00 2001
From: Thomas Sanders <thomas.sanders@citrix.com>
Date: Tue, 14 Mar 2017 12:15:52 +0000
Subject: [PATCH 03/15] oxenstored: comments explaining some variables
It took a while of reading and reasoning to work out what these are
for, so here are comments to make life easier for everyone reading
this code in future.
Reported-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Sanders <thomas.sanders@citrix.com>
Reviewed-by: Jonathan Davies <jonathan.davies@citrix.com>
Reviewed-by: Ian Jackson <ian.jackson@eu.citrix.com>
Reviewed-by: Christian Lindig <christian.lindig@citrix.com>
---
tools/ocaml/xenstored/store.ml | 1 +
tools/ocaml/xenstored/transaction.ml | 10 +++++++---
2 files changed, 8 insertions(+), 3 deletions(-)
diff --git a/tools/ocaml/xenstored/store.ml b/tools/ocaml/xenstored/store.ml
index 223ee21..9f619b8 100644
--- a/tools/ocaml/xenstored/store.ml
+++ b/tools/ocaml/xenstored/store.ml
@@ -211,6 +211,7 @@ let apply rnode path fct =
lookup rnode path fct
end
+(* The Store.t type *)
type t =
{
mutable stat_transaction_coalesce: int;
diff --git a/tools/ocaml/xenstored/transaction.ml b/tools/ocaml/xenstored/transaction.ml
index 6b37fc2..51d5d6a 100644
--- a/tools/ocaml/xenstored/transaction.ml
+++ b/tools/ocaml/xenstored/transaction.ml
@@ -69,11 +69,15 @@ let can_coalesce oldroot currentroot path =
else
false
-type ty = No | Full of (int * Store.Node.t * Store.t)
+type ty = No | Full of (
+ int * (* Transaction id *)
+ Store.Node.t * (* Original root *)
+ Store.t (* A pointer to the canonical store: its root changes on each transaction-commit *)
+)
type t = {
ty: ty;
- store: Store.t;
+ store: Store.t; (* This is the store that we change in write operations. *)
quota: Quota.t;
mutable paths: (Xenbus.Xb.Op.operation * Store.Path.t) list;
mutable operations: (Packet.request * Packet.response) list;
@@ -155,7 +159,7 @@ let commit ~con t =
let has_commited =
match t.ty with
| No -> true
- | Full (id, oldroot, cstore) ->
+ | Full (id, oldroot, cstore) -> (* "cstore" meaning current canonical store *)
let commit_partial oldroot cstore store =
(* get the lowest path of the query and verify that it hasn't
been modified by others transactions. *)
--
2.1.4
|
