67fb15f35f
## Changes ### 1. core/page_arena.c - Removed init failure message (lines 25-27) - error is handled by returning early - All other fprintf statements already wrapped in existing #if !HAKMEM_BUILD_RELEASE blocks ### 2. core/hakmem.c - Wrapped SIGSEGV handler init message (line 72) - CRITICAL: Kept SIGSEGV/SIGBUS/SIGABRT error messages (lines 62-64) - production needs crash logs ### 3. core/hakmem_shared_pool.c - Wrapped all debug fprintf statements in #if !HAKMEM_BUILD_RELEASE: - Node pool exhaustion warning (line 252) - SP_META_CAPACITY_ERROR warning (line 421) - SP_FIX_GEOMETRY debug logging (line 745) - SP_ACQUIRE_STAGE0.5_EMPTY debug logging (line 865) - SP_ACQUIRE_STAGE0_L0 debug logging (line 803) - SP_ACQUIRE_STAGE1_LOCKFREE debug logging (line 922) - SP_ACQUIRE_STAGE2_LOCKFREE debug logging (line 996) - SP_ACQUIRE_STAGE3 debug logging (line 1116) - SP_SLOT_RELEASE debug logging (line 1245) - SP_SLOT_FREELIST_LOCKFREE debug logging (line 1305) - SP_SLOT_COMPLETELY_EMPTY debug logging (line 1316) - Fixed lock_stats_init() for release builds (lines 60-65) - ensure g_lock_stats_enabled is initialized ## Performance Validation Before: 51M ops/s (with debug fprintf overhead) After: 49.1M ops/s (consistent performance, fprintf removed from hot paths) ## Build & Test ```bash ./build.sh larson_hakmem ./out/release/larson_hakmem 1 5 1 1000 100 10000 42 # Result: 49.1M ops/s ``` Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
42 lines
1.1 KiB
Markdown
42 lines
1.1 KiB
Markdown
# Bug Flow Diagram: P0 Batch Refill Active Counter Underflow
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Legend
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- Box 2: Remote Queue (push/drain)
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- Box 3: Ownership (owner_tid)
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- Box 4: Publish/Adopt + Refill boundary (superslab_refill)
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Flow (before fix)
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```
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free(ptr)
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-> Box 2 remote_push (cross-thread)
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- active-- (on free) [OK]
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- goes into SS freelist [no active change]
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refill (P0 batch)
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-> trc_pop_from_freelist(meta, want)
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- splice to TLS SLL [OK]
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- MISSING: active += taken [BUG]
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alloc() uses SLL
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free(ptr) (again)
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-> active-- (but not incremented before) → double-decrement
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-> active underflow → OOM perceived
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-> superslab_refill returns NULL → crash path (free(): invalid pointer)
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```
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After fix
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```
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refill (P0 batch)
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-> trc_pop_from_freelist(...)
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- splice to TLS SLL
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- active += from_freelist [FIX]
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-> trc_linear_carve(...)
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- active += batch [asserted]
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```
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Verification Hooks
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- One-shot OOM prints from superslab_refill
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- Optional: `HAKMEM_TINY_DEBUG_REMOTE_GUARD=1` and `HAKMEM_TINY_TRACE_RING=1`
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