diff options
Diffstat (limited to 'lib/system/gc.nim')
| -rw-r--r-- | lib/system/gc.nim | 73 |
1 files changed, 39 insertions, 34 deletions
diff --git a/lib/system/gc.nim b/lib/system/gc.nim index 703146484..8db60ab0f 100644 --- a/lib/system/gc.nim +++ b/lib/system/gc.nim @@ -12,9 +12,6 @@ # Refcounting + Mark&Sweep. Complex algorithms avoided. # Been there, done that, didn't work. -when defined(nimCoroutines): - import arch - {.push profiler:off.} const @@ -66,17 +63,24 @@ type cycleTableSize: int # max entries in cycle table maxPause: int64 # max measured GC pause in nanoseconds - GcStack {.final.} = object - prev: ptr GcStack - next: ptr GcStack - starts: pointer - pos: pointer - maxStackSize: int + GcStack {.final, pure.} = object + when nimCoroutines: + prev: ptr GcStack + next: ptr GcStack + maxStackSize: int # Used to track statistics because we can not use + # GcStat.maxStackSize when multiple stacks exist. + bottom: pointer + + when withRealTime or nimCoroutines: + pos: pointer # Used with `withRealTime` only for code clarity, see GC_Step(). + when withRealTime: + bottomSaved: pointer GcHeap {.final, pure.} = object # this contains the zero count and - # non-zero count table - stack: ptr GcStack - stackBottom: pointer + # non-zero count table + stack: GcStack + when nimCoroutines: + activeStack: ptr GcStack # current executing coroutine stack. cycleThreshold: int when useCellIds: idGenerator: int @@ -823,7 +827,10 @@ proc collectCTBody(gch: var GcHeap) = let t0 = getticks() sysAssert(allocInv(gch.region), "collectCT: begin") - when not defined(nimCoroutines): + when nimCoroutines: + for stack in gch.stack.items(): + gch.stat.maxStackSize = max(gch.stat.maxStackSize, stack.stackSize()) + else: gch.stat.maxStackSize = max(gch.stat.maxStackSize, stackSize()) sysAssert(gch.decStack.len == 0, "collectCT") prepareForInteriorPointerChecking(gch.region) @@ -849,19 +856,11 @@ proc collectCTBody(gch: var GcHeap) = if gch.maxPause > 0 and duration > gch.maxPause: c_fprintf(stdout, "[GC] missed deadline: %ld\n", duration) -when defined(nimCoroutines): - proc currentStackSizes(): int = - for stack in items(gch.stack): - result = result + stackSize(stack.starts, stack.pos) - proc collectCT(gch: var GcHeap) = # stackMarkCosts prevents some pathological behaviour: Stack marking # becomes more expensive with large stacks and large stacks mean that # cells with RC=0 are more likely to be kept alive by the stack. - when defined(nimCoroutines): - let stackMarkCosts = max(currentStackSizes() div (16*sizeof(int)), ZctThreshold) - else: - let stackMarkCosts = max(stackSize() div (16*sizeof(int)), ZctThreshold) + let stackMarkCosts = max(stackSize() div (16*sizeof(int)), ZctThreshold) if (gch.zct.len >= stackMarkCosts or (cycleGC and getOccupiedMem(gch.region)>=gch.cycleThreshold) or alwaysGC) and gch.recGcLock == 0: @@ -888,18 +887,24 @@ when withRealTime: release(gch) proc GC_step*(us: int, strongAdvice = false, stackSize = -1) {.noinline.} = - var stackTop {.volatile.}: pointer - let prevStackBottom = gch.stackBottom if stackSize >= 0: - stackTop = addr(stackTop) - when stackIncreases: - gch.stackBottom = cast[pointer]( - cast[ByteAddress](stackTop) - sizeof(pointer) * 6 - stackSize) - else: - gch.stackBottom = cast[pointer]( - cast[ByteAddress](stackTop) + sizeof(pointer) * 6 + stackSize) + var stackTop {.volatile.}: pointer + gch.getActiveStack().pos = addr(stackTop) + + for stack in gch.stack.items(): + stack.bottomSaved = stack.bottom + when stackIncreases: + stack.bottom = cast[pointer]( + cast[ByteAddress](stack.pos) - sizeof(pointer) * 6 - stackSize) + else: + stack.bottom = cast[pointer]( + cast[ByteAddress](stack.pos) + sizeof(pointer) * 6 + stackSize) + GC_step(gch, us, strongAdvice) - gch.stackBottom = prevStackBottom + + if stackSize >= 0: + for stack in gch.stack.items(): + stack.bottom = stack.bottomSaved when not defined(useNimRtl): proc GC_disable() = @@ -943,10 +948,10 @@ when not defined(useNimRtl): "[GC] zct capacity: " & $gch.zct.cap & "\n" & "[GC] max cycle table size: " & $gch.stat.cycleTableSize & "\n" & "[GC] max pause time [ms]: " & $(gch.stat.maxPause div 1000_000) & "\n" - when defined(nimCoroutines): + when nimCoroutines: result = result & "[GC] number of stacks: " & $gch.stack.len & "\n" for stack in items(gch.stack): - result = result & "[GC] stack " & stack.starts.repr & "[GC] max stack size " & $stack.maxStackSize & "\n" + result = result & "[GC] stack " & stack.bottom.repr & "[GC] max stack size " & cast[pointer](stack.maxStackSize).repr & "\n" else: result = result & "[GC] max stack size: " & $gch.stat.maxStackSize & "\n" GC_enable() |