Replace Status with IOStatus for block fetcher IO function (#8130)

Summary:
To propagate the IOStatus from file reads to RocksDB read logic, some of the existing status needs to be replaced by IOStatus.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8130

Test Plan: make check

Reviewed By: anand1976

Differential Revision: D27440188

Pulled By: zhichao-cao

fbshipit-source-id: bbe7622c2106fe4e46871d60f7c26944e5030d78

file/random_access_file_reader.cc

@@ -22,26 +22,26 @@
 #include "util/rate_limiter.h"
 
 namespace ROCKSDB_NAMESPACE {
-Status RandomAccessFileReader::Create(
+IOStatus RandomAccessFileReader::Create(
     const std::shared_ptr<FileSystem>& fs, const std::string& fname,
     const FileOptions& file_opts,
     std::unique_ptr<RandomAccessFileReader>* reader, IODebugContext* dbg) {
   std::unique_ptr<FSRandomAccessFile> file;
-  Status s = fs->NewRandomAccessFile(fname, file_opts, &file, dbg);
-  if (s.ok()) {
+  IOStatus io_s = fs->NewRandomAccessFile(fname, file_opts, &file, dbg);
+  if (io_s.ok()) {
     reader->reset(new RandomAccessFileReader(std::move(file), fname));
   }
-  return s;
+  return io_s;
 }
 
-Status RandomAccessFileReader::Read(const IOOptions& opts, uint64_t offset,
-                                    size_t n, Slice* result, char* scratch,
-                                    AlignedBuf* aligned_buf,
-                                    bool for_compaction) const {
+IOStatus RandomAccessFileReader::Read(const IOOptions& opts, uint64_t offset,
+                                      size_t n, Slice* result, char* scratch,
+                                      AlignedBuf* aligned_buf,
+                                      bool for_compaction) const {
   (void)aligned_buf;
 
   TEST_SYNC_POINT_CALLBACK("RandomAccessFileReader::Read", nullptr);
-  Status s;
+  IOStatus io_s;
   uint64_t elapsed = 0;
   {
     StopWatch sw(clock_, stats_, hist_type_,
@@ -86,22 +86,22 @@ Status RandomAccessFileReader::Read(const IOOptions& opts, uint64_t offset,
           // one iteration of this loop, so we don't need to check and adjust
           // the opts.timeout before calling file_->Read
           assert(!opts.timeout.count() || allowed == read_size);
-          s = file_->Read(aligned_offset + buf.CurrentSize(), allowed, opts,
-                          &tmp, buf.Destination(), nullptr);
+          io_s = file_->Read(aligned_offset + buf.CurrentSize(), allowed, opts,
+                             &tmp, buf.Destination(), nullptr);
         }
         if (ShouldNotifyListeners()) {
           auto finish_ts = FileOperationInfo::FinishNow();
           NotifyOnFileReadFinish(orig_offset, tmp.size(), start_ts, finish_ts,
-                                 s);
+                                 io_s);
         }
 
         buf.Size(buf.CurrentSize() + tmp.size());
-        if (!s.ok() || tmp.size() < allowed) {
+        if (!io_s.ok() || tmp.size() < allowed) {
           break;
         }
       }
       size_t res_len = 0;
-      if (s.ok() && offset_advance < buf.CurrentSize()) {
+      if (io_s.ok() && offset_advance < buf.CurrentSize()) {
         res_len = std::min(buf.CurrentSize() - offset_advance, n);
         if (aligned_buf == nullptr) {
           buf.Read(scratch, offset_advance, res_len);
@@ -146,14 +146,14 @@ Status RandomAccessFileReader::Read(const IOOptions& opts, uint64_t offset,
           // one iteration of this loop, so we don't need to check and adjust
           // the opts.timeout before calling file_->Read
           assert(!opts.timeout.count() || allowed == n);
-          s = file_->Read(offset + pos, allowed, opts, &tmp_result,
-                          scratch + pos, nullptr);
+          io_s = file_->Read(offset + pos, allowed, opts, &tmp_result,
+                             scratch + pos, nullptr);
         }
 #ifndef ROCKSDB_LITE
         if (ShouldNotifyListeners()) {
           auto finish_ts = FileOperationInfo::FinishNow();
           NotifyOnFileReadFinish(offset + pos, tmp_result.size(), start_ts,
-                                 finish_ts, s);
+                                 finish_ts, io_s);
         }
 #endif
 
@@ -166,11 +166,11 @@ Status RandomAccessFileReader::Read(const IOOptions& opts, uint64_t offset,
           assert(tmp_result.data() == res_scratch + pos);
         }
         pos += tmp_result.size();
-        if (!s.ok() || tmp_result.size() < allowed) {
+        if (!io_s.ok() || tmp_result.size() < allowed) {
           break;
         }
       }
-      *result = Slice(res_scratch, s.ok() ? pos : 0);
+      *result = Slice(res_scratch, io_s.ok() ? pos : 0);
     }
     IOSTATS_ADD_IF_POSITIVE(bytes_read, result->size());
     SetPerfLevel(prev_perf_level);
@@ -179,7 +179,7 @@ Status RandomAccessFileReader::Read(const IOOptions& opts, uint64_t offset,
     file_read_hist_->Add(elapsed);
   }
 
-  return s;
+  return io_s;
 }
 
 size_t End(const FSReadRequest& r) {
@@ -208,13 +208,13 @@ bool TryMerge(FSReadRequest* dest, const FSReadRequest& src) {
   return true;
 }
 
-Status RandomAccessFileReader::MultiRead(const IOOptions& opts,
-                                         FSReadRequest* read_reqs,
-                                         size_t num_reqs,
-                                         AlignedBuf* aligned_buf) const {
+IOStatus RandomAccessFileReader::MultiRead(const IOOptions& opts,
+                                           FSReadRequest* read_reqs,
+                                           size_t num_reqs,
+                                           AlignedBuf* aligned_buf) const {
   (void)aligned_buf;  // suppress warning of unused variable in LITE mode
   assert(num_reqs > 0);
-  Status s;
+  IOStatus io_s;
   uint64_t elapsed = 0;
   {
     StopWatch sw(clock_, stats_, hist_type_,
@@ -280,7 +280,7 @@ Status RandomAccessFileReader::MultiRead(const IOOptions& opts,
 
     {
       IOSTATS_CPU_TIMER_GUARD(cpu_read_nanos, clock_);
-      s = file_->MultiRead(fs_reqs, num_fs_reqs, opts, nullptr);
+      io_s = file_->MultiRead(fs_reqs, num_fs_reqs, opts, nullptr);
     }
 
 #ifndef ROCKSDB_LITE
@@ -321,7 +321,7 @@ Status RandomAccessFileReader::MultiRead(const IOOptions& opts,
     file_read_hist_->Add(elapsed);
   }
 
-  return s;
+  return io_s;
 }
 
 IOStatus RandomAccessFileReader::PrepareIOOptions(const ReadOptions& ro,

file/random_access_file_reader.h

@@ -103,10 +103,10 @@ class RandomAccessFileReader {
 #endif
   }
 
-  static Status Create(const std::shared_ptr<FileSystem>& fs,
-                       const std::string& fname, const FileOptions& file_opts,
-                       std::unique_ptr<RandomAccessFileReader>* reader,
-                       IODebugContext* dbg);
+  static IOStatus Create(const std::shared_ptr<FileSystem>& fs,
+                         const std::string& fname, const FileOptions& file_opts,
+                         std::unique_ptr<RandomAccessFileReader>* reader,
+                         IODebugContext* dbg);
   RandomAccessFileReader(const RandomAccessFileReader&) = delete;
   RandomAccessFileReader& operator=(const RandomAccessFileReader&) = delete;
 
@@ -120,19 +120,19 @@ class RandomAccessFileReader {
   // 2. Otherwise, scratch is not used and can be null, the aligned_buf owns
   // the internally allocated buffer on return, and the result refers to a
   // region in aligned_buf.
-  Status Read(const IOOptions& opts, uint64_t offset, size_t n, Slice* result,
-              char* scratch, AlignedBuf* aligned_buf,
-              bool for_compaction = false) const;
+  IOStatus Read(const IOOptions& opts, uint64_t offset, size_t n, Slice* result,
+                char* scratch, AlignedBuf* aligned_buf,
+                bool for_compaction = false) const;
 
   // REQUIRES:
   // num_reqs > 0, reqs do not overlap, and offsets in reqs are increasing.
   // In non-direct IO mode, aligned_buf should be null;
   // In direct IO mode, aligned_buf stores the aligned buffer allocated inside
   // MultiRead, the result Slices in reqs refer to aligned_buf.
-  Status MultiRead(const IOOptions& opts, FSReadRequest* reqs, size_t num_reqs,
-                   AlignedBuf* aligned_buf) const;
+  IOStatus MultiRead(const IOOptions& opts, FSReadRequest* reqs,
+                     size_t num_reqs, AlignedBuf* aligned_buf) const;
 
-  Status Prefetch(uint64_t offset, size_t n) const {
+  IOStatus Prefetch(uint64_t offset, size_t n) const {
     return file_->Prefetch(offset, n, IOOptions(), nullptr);
   }
 

table/block_fetcher.cc

@@ -29,9 +29,9 @@ namespace ROCKSDB_NAMESPACE {
 inline void BlockFetcher::CheckBlockChecksum() {
   // Check the crc of the type and the block contents
   if (read_options_.verify_checksums) {
-    status_ = ROCKSDB_NAMESPACE::VerifyBlockChecksum(
+    io_status_ = status_to_io_status(ROCKSDB_NAMESPACE::VerifyBlockChecksum(
         footer_.checksum(), slice_.data(), block_size_, file_->file_name(),
-        handle_.offset());
+        handle_.offset()));
   }
 }
 
@@ -59,18 +59,18 @@ inline bool BlockFetcher::TryGetUncompressBlockFromPersistentCache() {
 inline bool BlockFetcher::TryGetFromPrefetchBuffer() {
   if (prefetch_buffer_ != nullptr) {
     IOOptions opts;
-    Status s = file_->PrepareIOOptions(read_options_, opts);
-    if (s.ok() && prefetch_buffer_->TryReadFromCache(
-                      opts, handle_.offset(), block_size_with_trailer_, &slice_,
-                      &s, for_compaction_)) {
+    IOStatus io_s = file_->PrepareIOOptions(read_options_, opts);
+    if (io_s.ok() && prefetch_buffer_->TryReadFromCache(
+                         opts, handle_.offset(), block_size_with_trailer_,
+                         &slice_, &io_s, for_compaction_)) {
       CheckBlockChecksum();
-      if (!status_.ok()) {
+      if (!io_status_.ok()) {
         return true;
       }
       got_from_prefetch_buffer_ = true;
       used_buf_ = const_cast<char*>(slice_.data());
-    } else if (!s.ok()) {
-      status_ = s;
+    } else if (!io_s.ok()) {
+      io_status_ = io_s;
       return true;
     }
   }
@@ -82,18 +82,18 @@ inline bool BlockFetcher::TryGetCompressedBlockFromPersistentCache() {
       cache_options_.persistent_cache->IsCompressed()) {
     // lookup uncompressed cache mode p-cache
     std::unique_ptr<char[]> raw_data;
-    status_ = PersistentCacheHelper::LookupRawPage(
-        cache_options_, handle_, &raw_data, block_size_with_trailer_);
-    if (status_.ok()) {
+    io_status_ = status_to_io_status(PersistentCacheHelper::LookupRawPage(
+        cache_options_, handle_, &raw_data, block_size_with_trailer_));
+    if (io_status_.ok()) {
       heap_buf_ = CacheAllocationPtr(raw_data.release());
       used_buf_ = heap_buf_.get();
       slice_ = Slice(heap_buf_.get(), block_size_);
       return true;
-    } else if (!status_.IsNotFound() && ioptions_.info_log) {
-      assert(!status_.ok());
+    } else if (!io_status_.IsNotFound() && ioptions_.info_log) {
+      assert(!io_status_.ok());
       ROCKS_LOG_INFO(ioptions_.info_log,
                      "Error reading from persistent cache. %s",
-                     status_.ToString().c_str());
+                     io_status_.ToString().c_str());
     }
   }
   return false;
@@ -136,7 +136,7 @@ inline void BlockFetcher::PrepareBufferForBlockFromFile() {
 }
 
 inline void BlockFetcher::InsertCompressedBlockToPersistentCacheIfNeeded() {
-  if (status_.ok() && read_options_.fill_cache &&
+  if (io_status_.ok() && read_options_.fill_cache &&
       cache_options_.persistent_cache &&
       cache_options_.persistent_cache->IsCompressed()) {
     // insert to raw cache
@@ -146,8 +146,8 @@ inline void BlockFetcher::InsertCompressedBlockToPersistentCacheIfNeeded() {
 }
 
 inline void BlockFetcher::InsertUncompressedBlockToPersistentCacheIfNeeded() {
-  if (status_.ok() && !got_from_prefetch_buffer_ && read_options_.fill_cache &&
-      cache_options_.persistent_cache &&
+  if (io_status_.ok() && !got_from_prefetch_buffer_ &&
+      read_options_.fill_cache && cache_options_.persistent_cache &&
       !cache_options_.persistent_cache->IsCompressed()) {
     // insert to uncompressed cache
     PersistentCacheHelper::InsertUncompressedPage(cache_options_, handle_,
@@ -215,26 +215,26 @@ inline void BlockFetcher::GetBlockContents() {
 #endif
 }
 
-Status BlockFetcher::ReadBlockContents() {
+IOStatus BlockFetcher::ReadBlockContents() {
   if (TryGetUncompressBlockFromPersistentCache()) {
     compression_type_ = kNoCompression;
 #ifndef NDEBUG
     contents_->is_raw_block = true;
 #endif  // NDEBUG
-    return Status::OK();
+    return IOStatus::OK();
   }
   if (TryGetFromPrefetchBuffer()) {
-    if (!status_.ok()) {
-      return status_;
+    if (!io_status_.ok()) {
+      return io_status_;
     }
   } else if (!TryGetCompressedBlockFromPersistentCache()) {
     IOOptions opts;
-    status_ = file_->PrepareIOOptions(read_options_, opts);
+    io_status_ = file_->PrepareIOOptions(read_options_, opts);
     // Actual file read
-    if (status_.ok()) {
+    if (io_status_.ok()) {
       if (file_->use_direct_io()) {
         PERF_TIMER_GUARD(block_read_time);
-        status_ =
+        io_status_ =
             file_->Read(opts, handle_.offset(), block_size_with_trailer_,
                         &slice_, nullptr, &direct_io_buf_, for_compaction_);
         PERF_COUNTER_ADD(block_read_count, 1);
@@ -242,8 +242,9 @@ Status BlockFetcher::ReadBlockContents() {
       } else {
         PrepareBufferForBlockFromFile();
         PERF_TIMER_GUARD(block_read_time);
-        status_ = file_->Read(opts, handle_.offset(), block_size_with_trailer_,
-                              &slice_, used_buf_, nullptr, for_compaction_);
+        io_status_ =
+            file_->Read(opts, handle_.offset(), block_size_with_trailer_,
+                        &slice_, used_buf_, nullptr, for_compaction_);
         PERF_COUNTER_ADD(block_read_count, 1);
 #ifndef NDEBUG
         if (slice_.data() == &stack_buf_[0]) {
@@ -277,23 +278,23 @@ Status BlockFetcher::ReadBlockContents() {
     }
 
     PERF_COUNTER_ADD(block_read_byte, block_size_with_trailer_);
-    if (!status_.ok()) {
-      return status_;
+    if (!io_status_.ok()) {
+      return io_status_;
     }
 
     if (slice_.size() != block_size_with_trailer_) {
-      return Status::Corruption("truncated block read from " +
-                                file_->file_name() + " offset " +
-                                ToString(handle_.offset()) + ", expected " +
-                                ToString(block_size_with_trailer_) +
-                                " bytes, got " + ToString(slice_.size()));
+      return IOStatus::Corruption("truncated block read from " +
+                                  file_->file_name() + " offset " +
+                                  ToString(handle_.offset()) + ", expected " +
+                                  ToString(block_size_with_trailer_) +
+                                  " bytes, got " + ToString(slice_.size()));
     }
 
     CheckBlockChecksum();
-    if (status_.ok()) {
+    if (io_status_.ok()) {
       InsertCompressedBlockToPersistentCacheIfNeeded();
     } else {
-      return status_;
+      return io_status_;
     }
   }
 
@@ -304,9 +305,9 @@ Status BlockFetcher::ReadBlockContents() {
     // compressed page, uncompress, update cache
     UncompressionContext context(compression_type_);
     UncompressionInfo info(context, uncompression_dict_, compression_type_);
-    status_ = UncompressBlockContents(info, slice_.data(), block_size_,
-                                      contents_, footer_.version(), ioptions_,
-                                      memory_allocator_);
+    io_status_ = status_to_io_status(UncompressBlockContents(
+        info, slice_.data(), block_size_, contents_, footer_.version(),
+        ioptions_, memory_allocator_));
 #ifndef NDEBUG
     num_heap_buf_memcpy_++;
 #endif
@@ -317,7 +318,7 @@ Status BlockFetcher::ReadBlockContents() {
 
   InsertUncompressedBlockToPersistentCacheIfNeeded();
 
-  return status_;
+  return io_status_;
 }
 
 }  // namespace ROCKSDB_NAMESPACE

table/block_fetcher.h

@@ -64,7 +64,7 @@ class BlockFetcher {
         memory_allocator_compressed_(memory_allocator_compressed),
         for_compaction_(for_compaction) {}
 
-  Status ReadBlockContents();
+  IOStatus ReadBlockContents();
   CompressionType get_compression_type() const { return compression_type_; }
 
 #ifndef NDEBUG
@@ -100,7 +100,7 @@ class BlockFetcher {
   const PersistentCacheOptions& cache_options_;
   MemoryAllocator* memory_allocator_;
   MemoryAllocator* memory_allocator_compressed_;
-  Status status_;
+  IOStatus io_status_;
   Slice slice_;
   char* used_buf_ = nullptr;
   AlignedBuf direct_io_buf_;