Files
hakmem/core/hakmem_tiny_tls_ops.h
Moe Charm (CI) 6859d589ea Add Box 3 (Pointer Conversion Layer) and fix POOL_TLS_PHASE1 default
## Major Changes

### 1. Box 3: Pointer Conversion Module (NEW)
- File: core/box/ptr_conversion_box.h
- Purpose: Unified BASE ↔ USER pointer conversion (single source of truth)
- API: PTR_BASE_TO_USER(), PTR_USER_TO_BASE()
- Features: Zero-overhead inline, debug mode, NULL-safe, class 7 headerless support
- Design: Header-only, fully modular, no external dependencies

### 2. POOL_TLS_PHASE1 Default OFF (CRITICAL FIX)
- File: build.sh
- Change: POOL_TLS_PHASE1 now defaults to 0 (was hardcoded to 1)
- Impact: Eliminates pthread_mutex overhead on every free() (was causing 3.3x slowdown)
- Usage: Set POOL_TLS_PHASE1=1 env var to enable if needed

### 3. Pointer Conversion Fixes (PARTIAL)
- Files: core/box/front_gate_box.c, core/tiny_alloc_fast.inc.h, etc.
- Status: Partial implementation using Box 3 API
- Note: Work in progress, some conversions still need review

### 4. Performance Investigation Report (NEW)
- File: HOTPATH_PERFORMANCE_INVESTIGATION.md
- Findings:
  - Hotpath works (+24% vs baseline) after POOL_TLS fix
  - Still 9.2x slower than system malloc due to:
    * Heavy initialization (23.85% of cycles)
    * Syscall overhead (2,382 syscalls per 100K ops)
    * Workload mismatch (C7 1KB is 49.8%, but only C5 256B has hotpath)
    * 9.4x more instructions than system malloc

### 5. Known Issues
- SEGV at 20K-30K iterations (pre-existing bug, not related to pointer conversions)
- Root cause: Likely active counter corruption or TLS-SLL chain issues
- Status: Under investigation

## Performance Results (100K iterations, 256B)
- Baseline (Hotpath OFF): 7.22M ops/s
- Hotpath ON: 8.98M ops/s (+24% improvement ✓)
- System malloc: 82.2M ops/s (still 9.2x faster)

## Next Steps
- P0: Fix 20K-30K SEGV bug (GDB investigation needed)
- P1: Lazy initialization (+20-25% expected)
- P1: C7 (1KB) hotpath (+30-40% expected, biggest win)
- P2: Reduce syscalls (+15-20% expected)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>
2025-11-12 01:01:23 +09:00

280 lines
10 KiB
C

#ifndef HAKMEM_TINY_TLS_OPS_H
#define HAKMEM_TINY_TLS_OPS_H
#include "hakmem_tiny.h"
#include "hakmem_tiny_superslab.h"
#include "hakmem_super_registry.h"
#include "tiny_remote.h"
#include <stdint.h>
// Forward declarations for external dependencies
extern int g_use_superslab;
extern const size_t g_tiny_class_sizes[TINY_NUM_CLASSES];
extern __thread TinyTLSSlab g_tls_slabs[TINY_NUM_CLASSES];
extern __thread void* g_tls_sll_head[TINY_NUM_CLASSES];
extern __thread uint32_t g_tls_sll_count[TINY_NUM_CLASSES];
extern __thread void* g_fast_head[TINY_NUM_CLASSES];
extern __thread uint16_t g_fast_count[TINY_NUM_CLASSES];
extern __thread TinyTLSList g_tls_lists[TINY_NUM_CLASSES];
extern __thread TinySlab* g_tls_active_slab_a[TINY_NUM_CLASSES];
extern __thread TinySlab* g_tls_active_slab_b[TINY_NUM_CLASSES];
extern PaddedLock g_tiny_class_locks[TINY_NUM_CLASSES];
#if !HAKMEM_BUILD_RELEASE
extern __thread TinyTLSMag g_tls_mags[TINY_NUM_CLASSES];
void tiny_small_mags_init_once(void);
void tiny_mag_init_if_needed(int class_idx);
#endif
#if HAKMEM_BUILD_DEBUG
extern uint64_t g_tls_spill_ss_count[TINY_NUM_CLASSES];
extern uint64_t g_tls_spill_owner_count[TINY_NUM_CLASSES];
extern uint64_t g_tls_spill_mag_count[TINY_NUM_CLASSES];
extern uint64_t g_tls_spill_requeue_count[TINY_NUM_CLASSES];
#endif
// NOTE: Helper functions are defined in hakmem_tiny.c before this header is included
// No forward declarations needed - functions are already visible
// ============================================================================
// TLS Operations - Hot Path Functions (Inline for Performance)
// ============================================================================
// Refill TLS list from TLS-bound SuperSlab (100-line hot path)
static inline int tls_refill_from_tls_slab(int class_idx, TinyTLSList* tls, uint32_t want) {
if (!g_use_superslab || tls == NULL) return 0;
TinyTLSSlab* tls_slab = &g_tls_slabs[class_idx];
if (!tls_slab->ss) {
if (superslab_refill(class_idx) == NULL) return 0;
}
TinySlabMeta* meta = tls_slab->meta;
if (!meta) return 0;
uint32_t cap = tls_list_spill_threshold(tls);
if (tls->count >= cap) return 0;
uint32_t room = cap - tls->count;
if (want == 0u || want > room) want = room;
if (want == 0u) return 0;
// Use stride (class_size + header for C0-6, headerless for C7)
size_t block_stride = tiny_stride_for_class(class_idx);
// Header-aware TLS list next offset for chains we build here
#if HAKMEM_TINY_HEADER_CLASSIDX
const size_t next_off_tls = (class_idx == 7) ? 0 : 1;
#else
const size_t next_off_tls = 0;
#endif
void* accum_head = NULL;
void* accum_tail = NULL;
uint32_t total = 0u;
uint8_t* slab_base = tls_slab->slab_base ? tls_slab->slab_base
: (tls_slab->ss ? tiny_slab_base_for(tls_slab->ss, tls_slab->slab_idx) : NULL);
while (total < want) {
// 1) 再利用フリーリスト
if (meta->freelist) {
void* local_head = NULL;
void* local_tail = NULL;
uint32_t local = 0u;
uint32_t need = want - total;
while (local < need && meta->freelist) {
void* node = meta->freelist;
meta->freelist = *(void**)node; // freelist is base-linked
*(void**)((uint8_t*)node + next_off_tls) = local_head;
local_head = node;
if (!local_tail) local_tail = node;
local++;
}
if (local > 0u) {
// Do not adjust active here (blocks not yet returned to user)
meta->used += local;
if (!accum_head) {
accum_head = local_head;
accum_tail = local_tail;
} else {
*(void**)((uint8_t*)local_tail + next_off_tls) = accum_head;
accum_head = local_head;
}
total += local;
continue;
}
}
// 2) Superslab の線形領域からまとめて切り出す
if (meta->used >= meta->capacity) {
if (superslab_refill(class_idx) == NULL) break;
meta = tls_slab->meta;
if (!meta) break;
// Refresh stride/base after refill
block_stride = tiny_stride_for_class(class_idx);
slab_base = tls_slab->slab_base ? tls_slab->slab_base
: (tls_slab->ss ? tiny_slab_base_for(tls_slab->ss, tls_slab->slab_idx) : NULL);
continue;
}
uint32_t need = want - total;
uint32_t available = meta->capacity - meta->used;
if (available == 0u) continue;
if (need > available) need = available;
if (!slab_base) {
slab_base = tiny_slab_base_for(tls_slab->ss, tls_slab->slab_idx);
}
uint8_t* base_cursor = slab_base + ((size_t)meta->used * block_stride);
void* local_head = (void*)base_cursor;
uint8_t* cursor = base_cursor;
for (uint32_t i = 1; i < need; ++i) {
uint8_t* next = cursor + block_stride;
*(void**)(cursor + next_off_tls) = (void*)next;
cursor = next;
}
void* local_tail = (void*)cursor;
meta->used += need;
// Do not adjust active here (blocks not yet returned to user)
if (!accum_head) {
accum_head = local_head;
accum_tail = local_tail;
} else {
*(void**)((uint8_t*)local_tail + next_off_tls) = accum_head;
accum_head = local_head;
}
total += need;
}
if (total > 0u && accum_head) {
tls_list_bulk_put(tls, accum_head, accum_tail, total, class_idx);
return (int)total;
}
return 0;
}
// Spill excess TLS list back to owners (96-line hot path)
static inline void tls_list_spill_excess(int class_idx, TinyTLSList* tls) {
uint32_t cap = tls_list_spill_threshold(tls);
if (tls->count <= cap) return;
uint32_t excess = tls->count - cap;
void* head = NULL;
void* tail = NULL;
uint32_t taken = tls_list_bulk_take(tls, excess, &head, &tail, class_idx);
if (taken == 0u || head == NULL) return;
#if HAKMEM_PROF_STATIC && HAKMEM_BUILD_DEBUG
struct timespec ts_tls;
int prof_sample = hkm_prof_begin(&ts_tls);
#endif
#if !HAKMEM_BUILD_RELEASE
tiny_small_mags_init_once();
if (class_idx > 3) tiny_mag_init_if_needed(class_idx);
TinyTLSMag* mag = &g_tls_mags[class_idx];
#else
TinyTLSMag* mag = NULL;
(void)mag;
#endif
void* requeue_head = NULL;
void* requeue_tail = NULL;
uint32_t requeue_count = 0;
uint32_t self_tid = tiny_self_u32();
void* node = head;
#if HAKMEM_TINY_HEADER_CLASSIDX
const size_t next_off_tls = (class_idx == 7) ? 0 : 1;
#else
const size_t next_off_tls = 0;
#endif
while (node) {
void* next = *(void**)((uint8_t*)node + next_off_tls);
int handled = 0;
// Phase 1: Try SuperSlab first (registry-based lookup, no false positives)
SuperSlab* ss = hak_super_lookup(node);
if (ss && ss->magic == SUPERSLAB_MAGIC) {
int slab_idx = slab_index_for(ss, node);
TinySlabMeta* meta = &ss->slabs[slab_idx];
if (!tiny_remote_guard_allow_local_push(ss, slab_idx, meta, node, "tls_spill_ss", self_tid)) {
(void)ss_remote_push(ss, slab_idx, node);
if (meta->used > 0) meta->used--;
handled = 1;
} else {
void* prev = meta->freelist;
*(void**)((uint8_t*)node + 0) = prev; // freelist within slab uses base link
meta->freelist = node;
tiny_failfast_log("tls_spill_ss", ss->size_class, ss, meta, node, prev);
if (meta->used > 0) meta->used--;
// Active was decremented at free time
handled = 1;
}
#if HAKMEM_BUILD_DEBUG
g_tls_spill_ss_count[class_idx]++;
#endif
tiny_obs_record(3, class_idx); // TINY_OBS_SPILL_SS
}
if (!handled) {
TinySlab* owner = tls_active_owner_for_ptr(class_idx, node);
if (owner && !mini_mag_is_full(&owner->mini_mag)) {
mini_mag_push(&owner->mini_mag, node);
handled = 1;
#if HAKMEM_BUILD_DEBUG
g_tls_spill_owner_count[class_idx]++;
#endif
tiny_obs_record(4, class_idx); // TINY_OBS_SPILL_OWNER
}
}
#if !HAKMEM_BUILD_RELEASE
if (!handled) {
if (mag && mag->cap > 0 && mag->top < mag->cap) {
mag->items[mag->top].ptr = node;
#if HAKMEM_TINY_MAG_OWNER
TinySlab* owner_hint = tls_active_owner_for_ptr(class_idx, node);
mag->items[mag->top].owner = owner_hint;
#endif
mag->top++;
if (__builtin_expect(tiny_remote_watch_is(node), 0)) {
SuperSlab* watch_ss = hak_super_lookup(node);
int watch_idx = (watch_ss && watch_ss->magic == SUPERSLAB_MAGIC) ? slab_index_for(watch_ss, node) : -1;
tiny_remote_watch_note("mag_push", watch_ss, watch_idx, node, 0xA242u, 0, 0);
}
handled = 1;
#if HAKMEM_BUILD_DEBUG
g_tls_spill_mag_count[class_idx]++;
#endif
tiny_obs_record(5, class_idx); // TINY_OBS_SPILL_MAG
}
}
#endif
if (!handled) {
*(void**)((uint8_t*)node + next_off_tls) = requeue_head;
if (!requeue_head) requeue_tail = node;
requeue_head = node;
requeue_count++;
#if HAKMEM_BUILD_DEBUG
g_tls_spill_requeue_count[class_idx]++;
#endif
tiny_obs_record(6, class_idx); // TINY_OBS_SPILL_REQUEUE
}
node = next;
}
if (requeue_head) {
tls_list_bulk_put(tls, requeue_head, requeue_tail, requeue_count, class_idx);
}
#if HAKMEM_PROF_STATIC && HAKMEM_BUILD_DEBUG
hkm_prof_end(prof_sample, HKP_TINY_TLS_SPILL, &ts_tls);
#endif
}
// ============================================================================
// TLS Operations - Cold Path Functions (Implemented in .c)
// ============================================================================
// Drain all TLS caches back to global pool (cold path, 89 lines)
void tiny_tls_cache_drain(int class_idx);
#endif // HAKMEM_TINY_TLS_OPS_H