[Pfc] Fix error handling in File::ReadV().

src/XrdPfc/XrdPfcFile.cc

@@ -209,18 +209,13 @@ bool File::ioActive(IO *io)
          TRACE(Info, "ioActive for io " << io <<
                 ", active_prefetches "       << mi->second.m_active_prefetches <<
                 ", allow_prefetching "       << mi->second.m_allow_prefetching <<
-                ", ioactive_false_reported " << mi->second.m_ioactive_false_reported <<
                 ", ios_in_detach "           << m_ios_in_detach);
          TRACEF(Info,
                 "\tio_map.size() "           << m_io_map.size() <<
                 ", block_map.size() "        << m_block_map.size() << ", file");
 
          insert_remote_location(loc);
 
-         // XXX Intermediate check for 4.11 - 5.0 transition.
-         // Can be removed for 5.1, including member IODetals::m_ioactive_false_reported.
-         assert( ! mi->second.m_ioactive_false_reported && "ioActive already returned false");
-
          mi->second.m_allow_prefetching = false;
 
          // Check if any IO is still available for prfetching. If not, stop it.
@@ -249,7 +244,6 @@ bool File::ioActive(IO *io)
          if ( ! io_active_result)
          {
             ++m_ios_in_detach;
-            mi->second.m_ioactive_false_reported = true;
          }
 
          TRACEF(Info, "ioActive for io " << io << " returning " << io_active_result << ", file");
@@ -1093,12 +1087,11 @@ void File::inc_ref_count(Block* b)
 void File::dec_ref_count(Block* b)
 {
    // Method always called under lock.
+   assert(b->is_finished());
    b->m_refcnt--;
    assert(b->m_refcnt >= 0);
 
-   // File::Read() can decrease ref count before waiting for the block in case
-   // of an error. Prefetch starts with refcnt 0.
-   if (b->m_refcnt == 0 && b->is_finished())
+   if (b->m_refcnt == 0)
    {
       free_block(b);
    }

src/XrdPfc/XrdPfcFile.hh

@@ -264,13 +264,11 @@ private:
       time_t m_attach_time;
       int    m_active_prefetches;
       bool   m_allow_prefetching;
-      bool   m_ioactive_false_reported;
 
       IODetails(time_t at) :
          m_attach_time             (at),
          m_active_prefetches       (0),
-         m_allow_prefetching       (true),
-         m_ioactive_false_reported (false)
+         m_allow_prefetching       (true)
       {}
    };
 

src/XrdPfc/XrdPfcVRead.cc

@@ -348,8 +348,10 @@ int File::VReadProcessBlocks(IO *io, const XrdOucIOVec *readV, int n,
                              long long& bytes_hit,
                              long long& bytes_missed)
 {
-   int bytes_read = 0;
-   while ( ! blocks_to_process.empty() && bytes_read >= 0)
+   long long bytes_read = 0;
+   int       error_cond = 0; // to be set to -errno
+
+   while ( ! blocks_to_process.empty())
    {
       std::vector<ReadVChunkListRAM> finished;
       BlockList_t                    to_reissue;
@@ -418,10 +420,14 @@ int File::VReadProcessBlocks(IO *io, const XrdOucIOVec *readV, int n,
          }
          else
          {
-            bytes_read = bi->block->m_errno;
-            TRACEF(Error, "VReadProcessBlocks() io " << io << ", block "<< bi->block <<
-                   " finished with error " << -bytes_read << " " << XrdSysE2T(-bytes_read));
-            break;
+            // It has failed ... report only the first error.
+            if ( ! error_cond)
+            {
+               error_cond = bi->block->m_errno;
+               TRACEF(Error, "VReadProcessBlocks() io " << io << ", block "<< bi->block <<
+                     " finished with error " << -error_cond << " " << XrdSysE2T(-error_cond));
+               break;
+            }
          }
 
          ++bi;
@@ -432,7 +438,7 @@ int File::VReadProcessBlocks(IO *io, const XrdOucIOVec *readV, int n,
       finished.clear();
    }
 
-   TRACEF(Dump, "VReadProcessBlocks total read  " <<  bytes_read);
+   TRACEF(Dump, "VReadProcessBlocks status " << error_cond << ", total read " <<  bytes_read);
 
-   return bytes_read;
+   return error_cond ? error_cond : bytes_read;
 }