Hi,

there are mostly stabilization, refactoring and cleanup changes. There rest are minor performance optimizations due to caching or lock contention reduction and a few notable fixes.

Please pull, thanks.

Performance improvements:

• minor speedup in logging when repeatedly allocated structure is preallocated only once, improves latency and decreases lock contention
• minor throughput increase (+6%), reduced lock contention after clearing delayed allocation bits, applies to several common workload types
• skip full quota rescan if a new relation is added in the same transaction

Fixes:

• zstd fix for inline compressed file in subpage mode, updated version from the 6.8 time
• proper qgroup inheritance ioctl parameter validation
• more fiemap followup fixes after reduced locking done in 6.8
  • fix race when detecting delalloc ranges

Core changes:

• more debugging code
  • added assertions for a very rare crash in raid56 calculation
  • tree-checker dumps page state to give more insights into possible reference counting issues
• add checksum calculation offloading sysfs knob, for now enabled under DEBUG only to determine a good heuristic for deciding the offload or synchronous, depends on various factors (block group profile, device speed) and is not as clear as initially thought (checksum type)
• error handling improvements, added assertions
• more page to folio conversion (defrag, truncate), cached size and shift
• preparation for more fine grained locking of sectors in subpage mode
• cleanups and refactoring
  • include cleanups, forward declarations
  • pointer-to-structure helpers
  • redundant argument removals
  • removed unused code
  • slab cache updates, last use of SLAB_MEM_SPREAD removed