From a724ceba0ccbf46eecb515d66f9b1ad852656550 Mon Sep 17 00:00:00 2001
From: Casey Bodley <cbodley@redhat.com>
Date: Mon, 23 Jan 2017 15:17:32 -0500
Subject: [PATCH] rgw: add PurgePeriodLogsCR to purge entire mdlog periods

Conflicts: rgw_raw_obj
        src/rgw/rgw_sync.cc

Signed-off-by: Casey Bodley <cbodley@redhat.com>
(cherry picked from commit 32d16a9557fe61fe35b1670e86b20b0a4184e7ca)
---
 src/rgw/rgw_sync.cc | 105 +++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 104 insertions(+), 1 deletion(-)

diff --git a/src/rgw/rgw_sync.cc b/src/rgw/rgw_sync.cc
index 24917baee133a..91424a1c47024 100644
--- a/src/rgw/rgw_sync.cc
+++ b/src/rgw/rgw_sync.cc
@@ -2290,10 +2290,113 @@ int RGWCloneMetaLogCoroutine::state_store_mdlog_entries_complete()
 #undef dout_prefix
 #define dout_prefix (*_dout << "meta trim: ")
 
-namespace {
+/// purge all log shards for the given mdlog
+class PurgeLogShardsCR : public RGWShardCollectCR {
+  RGWRados *const store;
+  const RGWMetadataLog* mdlog;
+  const int num_shards;
+  const rgw_bucket& pool;
+  int i{0};
+
+  static constexpr int max_concurrent = 16;
+
+ public:
+  PurgeLogShardsCR(RGWRados *store, const RGWMetadataLog* mdlog,
+                   const rgw_bucket& pool, int num_shards)
+    : RGWShardCollectCR(store->ctx(), max_concurrent),
+      store(store), mdlog(mdlog), num_shards(num_shards), pool(pool)
+  {}
+
+  bool spawn_next() override {
+    if (i == num_shards) {
+      return false;
+    }
+    std::string oid;
+    mdlog->get_shard_oid(i++, oid);
+    spawn(new RGWRadosRemoveCR(store, pool, oid), false);
+    return true;
+  }
+};
 
 using Cursor = RGWPeriodHistory::Cursor;
 
+/// purge mdlogs from the oldest up to (but not including) the given realm_epoch
+class PurgePeriodLogsCR : public RGWCoroutine {
+  RGWRados *const store;
+  RGWMetadataManager *const metadata;
+  RGWObjVersionTracker objv;
+  Cursor cursor;
+  epoch_t realm_epoch;
+  epoch_t *last_trim_epoch; //< update last trim on success
+
+ public:
+  PurgePeriodLogsCR(RGWRados *store, epoch_t realm_epoch, epoch_t *last_trim)
+    : RGWCoroutine(store->ctx()), store(store), metadata(store->meta_mgr),
+      realm_epoch(realm_epoch), last_trim_epoch(last_trim)
+  {}
+
+  int operate();
+};
+
+int PurgePeriodLogsCR::operate()
+{
+  reenter(this) {
+    // read our current oldest log period
+    yield call(metadata->read_oldest_log_period_cr(&cursor, &objv));
+    if (retcode < 0) {
+      return set_cr_error(retcode);
+    }
+    assert(cursor);
+    ldout(cct, 20) << "oldest log realm_epoch=" << cursor.get_epoch()
+        << " period=" << cursor.get_period().get_id() << dendl;
+
+    // trim -up to- the given realm_epoch
+    while (cursor.get_epoch() < realm_epoch) {
+      ldout(cct, 4) << "purging log shards for realm_epoch=" << cursor.get_epoch()
+          << " period=" << cursor.get_period().get_id() << dendl;
+      yield {
+        const auto mdlog = metadata->get_log(cursor.get_period().get_id());
+        const auto& pool = store->get_zone_params().log_pool;
+        auto num_shards = cct->_conf->rgw_md_log_max_shards;
+        call(new PurgeLogShardsCR(store, mdlog, pool, num_shards));
+      }
+      if (retcode < 0) {
+        ldout(cct, 1) << "failed to remove log shards: "
+            << cpp_strerror(retcode) << dendl;
+        return set_cr_error(retcode);
+      }
+      ldout(cct, 10) << "removed log shards for realm_epoch=" << cursor.get_epoch()
+          << " period=" << cursor.get_period().get_id() << dendl;
+
+      // update our mdlog history
+      yield call(metadata->trim_log_period_cr(cursor, &objv));
+      if (retcode == -ENOENT) {
+        // must have raced to update mdlog history. return success and allow the
+        // winner to continue purging
+        ldout(cct, 10) << "already removed log shards for realm_epoch=" << cursor.get_epoch()
+            << " period=" << cursor.get_period().get_id() << dendl;
+        return set_cr_done();
+      } else if (retcode < 0) {
+        ldout(cct, 1) << "failed to remove log shards for realm_epoch="
+            << cursor.get_epoch() << " period=" << cursor.get_period().get_id()
+            << " with: " << cpp_strerror(retcode) << dendl;
+        return set_cr_error(retcode);
+      }
+
+      if (*last_trim_epoch < cursor.get_epoch()) {
+        *last_trim_epoch = cursor.get_epoch();
+      }
+
+      assert(cursor.has_next()); // get_current() should always come after
+      cursor.next();
+    }
+    return set_cr_done();
+  }
+  return 0;
+}
+
+namespace {
+
 using connection_map = std::map<std::string, std::unique_ptr<RGWRESTConn>>;
 
 /// construct a RGWRESTConn for each zone in the realm
-- 
2.39.5