From 7c8a1cd31f174cd391f0b215c72f34ee24f7061f Mon Sep 17 00:00:00 2001
From: Sage Weil <sage@redhat.com>
Date: Fri, 7 Nov 2014 16:35:41 -0800
Subject: [PATCH] osd/Watch: drop redundant in_progress_watchers

This is essentially watchers.size() at all times and obfuscates the code.
In particular this makes the maybe_complete_notify() logic much clearer.

Signed-off-by: Sage Weil <sage@redhat.com>
---
 src/osd/ReplicatedPG.cc |  1 -
 src/osd/Watch.cc        | 17 +++++------------
 src/osd/Watch.h         |  7 ++-----
 3 files changed, 7 insertions(+), 18 deletions(-)

diff --git a/src/osd/ReplicatedPG.cc b/src/osd/ReplicatedPG.cc
index 90fa1d53bfe80..084f85102f2e7 100644
--- a/src/osd/ReplicatedPG.cc
+++ b/src/osd/ReplicatedPG.cc
@@ -5419,7 +5419,6 @@ void ReplicatedPG::do_osd_op_effects(OpContext *ctx)
       Notify::makeNotifyRef(
 	conn,
 	ctx->reqid.name.num(),
-	ctx->obc->watchers.size(),
 	p->bl,
 	p->timeout,
 	p->cookie,
diff --git a/src/osd/Watch.cc b/src/osd/Watch.cc
index 78d82993f300c..9ca852a2621de 100644
--- a/src/osd/Watch.cc
+++ b/src/osd/Watch.cc
@@ -29,7 +29,6 @@ static ostream& _prefix(
 Notify::Notify(
   ConnectionRef client,
   uint64_t client_gid,
-  unsigned num_watchers,
   bufferlist &payload,
   uint32_t timeout,
   uint64_t cookie,
@@ -37,7 +36,6 @@ Notify::Notify(
   uint64_t version,
   OSDService *osd)
   : client(client), client_gid(client_gid),
-    in_progress_watchers(num_watchers),
     complete(false),
     discarded(false),
     timed_out(false),
@@ -53,7 +51,6 @@ Notify::Notify(
 NotifyRef Notify::makeNotifyRef(
   ConnectionRef client,
   uint64_t client_gid,
-  unsigned num_watchers,
   bufferlist &payload,
   uint32_t timeout,
   uint64_t cookie,
@@ -62,7 +59,7 @@ NotifyRef Notify::makeNotifyRef(
   OSDService *osd) {
   NotifyRef ret(
     new Notify(
-      client, client_gid, num_watchers,
+      client, client_gid,
       payload, timeout,
       cookie, notify_id,
       version, osd));
@@ -100,7 +97,6 @@ void Notify::do_timeout()
     return;
   }
 
-  in_progress_watchers = 0; // we give up
   timed_out = true;         // we will send the client an error code
   maybe_complete_notify();
   assert(complete);
@@ -160,9 +156,8 @@ void Notify::complete_watcher(WatchRef watch, bufferlist& reply_bl)
   dout(10) << "complete_watcher" << dendl;
   if (is_discarded())
     return;
-  assert(in_progress_watchers > 0);
+  assert(watchers.count(watch));
   watchers.erase(watch);
-  --in_progress_watchers;
   notify_replies.insert(make_pair(watch->get_watcher_gid(), reply_bl));
   maybe_complete_notify();
 }
@@ -173,18 +168,17 @@ void Notify::complete_watcher_remove(WatchRef watch)
   dout(10) << __func__ << dendl;
   if (is_discarded())
     return;
-  assert(in_progress_watchers > 0);
+  assert(watchers.count(watch));
   watchers.erase(watch);
-  --in_progress_watchers;
   maybe_complete_notify();
 }
 
 void Notify::maybe_complete_notify()
 {
   dout(10) << "maybe_complete_notify -- "
-	   << in_progress_watchers
+	   << watchers.size()
 	   << " in progress watchers " << dendl;
-  if (!in_progress_watchers) {
+  if (watchers.empty() || timed_out) {
     bufferlist bl;
     ::encode(notify_replies, bl);
     bufferlist empty;
@@ -213,7 +207,6 @@ void Notify::init()
   Mutex::Locker l(lock);
   register_cb();
   maybe_complete_notify();
-  assert(in_progress_watchers == watchers.size());
 }
 
 #define dout_subsys ceph_subsys_osd
diff --git a/src/osd/Watch.h b/src/osd/Watch.h
index dee3e1e2f59c6..7eb42e13c6de3 100644
--- a/src/osd/Watch.h
+++ b/src/osd/Watch.h
@@ -56,7 +56,6 @@ class Notify {
   WNotifyRef self;
   ConnectionRef client;
   uint64_t client_gid;
-  unsigned in_progress_watchers;
   bool complete;
   bool discarded;
   bool timed_out;  ///< true if the notify timed out
@@ -80,7 +79,7 @@ class Notify {
     return discarded || complete;
   }
 
-  /// Sends notify completion if in_progress_watchers == 0
+  /// Sends notify completion if watchers.empty() or timeout
   void maybe_complete_notify();
 
   /// Called on Notify timeout
@@ -89,7 +88,6 @@ class Notify {
   Notify(
     ConnectionRef client,
     uint64_t client_gid,
-    unsigned num_watchers,
     bufferlist &payload,
     uint32_t timeout,
     uint64_t cookie,
@@ -107,7 +105,7 @@ public:
   string gen_dbg_prefix() {
     stringstream ss;
     ss << "Notify(" << make_pair(cookie, notify_id) << " "
-       << " in_progress_watchers=" << in_progress_watchers
+       << " watchers=" << watchers.size()
        << ") ";
     return ss.str();
   }
@@ -117,7 +115,6 @@ public:
   static NotifyRef makeNotifyRef(
     ConnectionRef client,
     uint64_t client_gid,
-    unsigned num_watchers,
     bufferlist &payload,
     uint32_t timeout,
     uint64_t cookie,
-- 
2.39.5