From c2f9d088d5363c234ddcb7b931460c23b0ce18ab Mon Sep 17 00:00:00 2001
From: Leonid Yuriev <leo@yuriev.ru>
Date: Sat, 22 Jun 2019 18:46:41 +0300
Subject: [PATCH] mdbx: rework RECLAIMING inside update_gc().

Change-Id: I9cf592476780bfdb346472baa12497d68a3d5aad
---
 src/mdbx.c | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/src/mdbx.c b/src/mdbx.c
index 9036d7c0..6c5f1560 100644
--- a/src/mdbx.c
+++ b/src/mdbx.c
@@ -3755,6 +3755,7 @@ static int mdbx_prep_backlog(MDBX_txn *txn, MDBX_cursor *mc) {
   const int extra = mdbx_backlog_extragap(txn->mt_env);
 
   if (mdbx_backlog_size(txn) < mc->mc_db->md_depth + extra) {
+    mc->mc_flags &= ~C_RECLAIMING;
     int rc = mdbx_cursor_touch(mc);
     if (unlikely(rc))
       return rc;
@@ -3768,6 +3769,7 @@ static int mdbx_prep_backlog(MDBX_txn *txn, MDBX_cursor *mc) {
         break;
       }
     }
+    mc->mc_flags |= C_RECLAIMING;
   }
 
   return MDBX_SUCCESS;
@@ -3880,6 +3882,7 @@ static int mdbx_update_gc(MDBX_txn *txn) {
   if (unlikely(rc != MDBX_SUCCESS))
     goto bailout_notracking;
 
+  mc.mc_flags |= C_RECLAIMING;
   mc.mc_next = txn->mt_cursors[FREE_DBI];
   txn->mt_cursors[FREE_DBI] = &mc;
 
@@ -3925,9 +3928,7 @@ retry:
           mdbx_tassert(txn, cleaned_gc_id < *env->me_oldest);
           mdbx_trace("%s.cleanup-reclaimed-id [%u]%" PRIaTXN, dbg_prefix_mode,
                      cleaned_gc_slot, cleaned_gc_id);
-          mc.mc_flags |= C_RECLAIMING;
           rc = mdbx_cursor_del(&mc, 0);
-          mc.mc_flags ^= C_RECLAIMING;
           if (unlikely(rc != MDBX_SUCCESS))
             goto bailout;
         } while (cleaned_gc_slot < MDBX_PNL_SIZE(txn->mt_lifo_reclaimed));
@@ -3949,9 +3950,7 @@ retry:
         mdbx_tassert(txn, cleaned_gc_id < *env->me_oldest);
         mdbx_trace("%s.cleanup-reclaimed-id %" PRIaTXN, dbg_prefix_mode,
                    cleaned_gc_id);
-        mc.mc_flags |= C_RECLAIMING;
         rc = mdbx_cursor_del(&mc, 0);
-        mc.mc_flags ^= C_RECLAIMING;
         if (unlikely(rc != MDBX_SUCCESS))
           goto bailout;
         settled = 0;
@@ -4104,7 +4103,9 @@ retry:
     if (befree_stored < MDBX_PNL_SIZE(txn->mt_befree_pages)) {
       if (unlikely(!befree_stored)) {
         /* Make sure last page of freeDB is touched and on befree-list */
+        mc.mc_flags &= ~C_RECLAIMING;
         rc = mdbx_page_search(&mc, NULL, MDBX_PS_LAST | MDBX_PS_MODIFY);
+        mc.mc_flags |= C_RECLAIMING;
         if (unlikely(rc != MDBX_SUCCESS && rc != MDBX_NOTFOUND))
           goto bailout;
       }
@@ -4198,7 +4199,9 @@ retry:
                   reused_gc_slot) *
                      env->me_maxgc_ov1page) {
         /* LY: need just a txn-id for save page list. */
+        mc.mc_flags &= ~C_RECLAIMING;
         rc = mdbx_page_alloc(&mc, 0, NULL, MDBX_ALLOC_GC | MDBX_ALLOC_KICK);
+        mc.mc_flags |= C_RECLAIMING;
         if (likely(rc == MDBX_SUCCESS)) {
           /* LY: ok, reclaimed from freedb. */
           mdbx_trace("%s: took @%" PRIaTXN " from GC, continue",
@@ -4320,9 +4323,7 @@ retry:
     data.iov_len = (chunk + 1) * sizeof(pgno_t);
     mdbx_trace("%s.reserve: %u [%u...%u] @%" PRIaTXN, dbg_prefix_mode, chunk,
                settled + 1, settled + chunk + 1, reservation_gc_id);
-    mc.mc_flags |= C_RECLAIMING;
     rc = mdbx_cursor_put(&mc, &key, &data, MDBX_RESERVE | MDBX_NOOVERWRITE);
-    mc.mc_flags -= C_RECLAIMING;
     mdbx_tassert(txn, mdbx_pnl_check(env->me_reclaimed_pglist, true));
     if (unlikely(rc != MDBX_SUCCESS))
       goto bailout;
@@ -4414,7 +4415,7 @@ retry:
       key.iov_len = sizeof(fill_gc_id);
 
       mdbx_tassert(txn, data.iov_len >= sizeof(pgno_t) * 2);
-      mc.mc_flags |= C_RECLAIMING | C_GCFREEZE;
+      mc.mc_flags |= C_GCFREEZE;
       unsigned chunk = (unsigned)(data.iov_len / sizeof(pgno_t)) - 1;
       if (unlikely(chunk > left)) {
         mdbx_trace("%s: chunk %u > left %u, @%" PRIaTXN, dbg_prefix_mode, chunk,
@@ -4422,12 +4423,12 @@ retry:
         if (loop < 5 || chunk - left > env->me_maxgc_ov1page) {
           data.iov_len = (left + 1) * sizeof(pgno_t);
           if (loop < 21)
-            mc.mc_flags -= C_GCFREEZE;
+            mc.mc_flags &= ~C_GCFREEZE;
         }
         chunk = left;
       }
       rc = mdbx_cursor_put(&mc, &key, &data, MDBX_CURRENT | MDBX_RESERVE);
-      mc.mc_flags &= ~(C_RECLAIMING | C_GCFREEZE);
+      mc.mc_flags &= ~C_GCFREEZE;
       if (unlikely(rc != MDBX_SUCCESS))
         goto bailout;