terminal/command: add -per-g-hitcount option to condition command (#3055)

Support use per goroutine hitcount as hintcond operand.

Fixes #3050

Co-authored-by: roketyyang <roketyyang@tencent.com>

Documentation/cli/README.md

@@ -180,6 +180,7 @@ Set breakpoint condition.
 
 	condition <breakpoint name or id> <boolean expression>.
 	condition -hitcount <breakpoint name or id> <operator> <argument>.
+	condition -per-g-hitcount <breakpoint name or id> <operator> <argument>.
 	condition -clear <breakpoint name or id>.
 
 Specifies that the breakpoint, tracepoint or watchpoint should break only if the boolean expression is true.
@@ -196,6 +197,8 @@ With the -hitcount option a condition on the breakpoint hit count can be set, th
 	condition -hitcount bp != n
 	condition -hitcount bp % n
 
+The -per-g-hitcount option works like -hitcount, but use per goroutine hitcount to compare with n.
+
 With the -clear option a condtion on the breakpoint can removed.
 	
 The '% n' form means we should stop at the breakpoint when the hitcount is a multiple of n.

_fixtures/condperghitcount.go

@@ -0,0 +1,25 @@
+package main
+
+import (
+	"sync"
+	"time"
+)
+
+func main() {
+	var wg sync.WaitGroup
+	wg.Add(2)
+	for i := 0; i < 2; i++ {
+		go func() {
+			j := 0
+			for {
+				j++
+				if j > 10 {
+					break
+				}
+			}
+			wg.Done()
+		}()
+		time.Sleep(time.Second)
+	}
+	wg.Wait()
+}

pkg/proc/breakpoints.go

@@ -264,14 +264,16 @@ func (bpstate *BreakpointState) checkCond(tgt *Target, breaklet *Breaklet, threa
 
 	switch breaklet.Kind {
 	case UserBreakpoint:
+		var goroutineID int
 		lbp := bpstate.Breakpoint.Logical
 		if lbp != nil {
 			if g, err := GetG(thread); err == nil {
-				lbp.HitCount[g.ID]++
+				goroutineID = g.ID
+				lbp.HitCount[goroutineID]++
 			}
 			lbp.TotalHitCount++
 		}
-		active = checkHitCond(lbp)
+		active = checkHitCond(lbp, goroutineID)
 
 	case StepBreakpoint, NextBreakpoint, NextDeferBreakpoint:
 		nextDeferOk := true
@@ -318,26 +320,30 @@ func (bpstate *BreakpointState) checkCond(tgt *Target, breaklet *Breaklet, threa
 }
 
 // checkHitCond evaluates bp's hit condition on thread.
-func checkHitCond(lbp *LogicalBreakpoint) bool {
+func checkHitCond(lbp *LogicalBreakpoint, goroutineID int) bool {
 	if lbp == nil || lbp.HitCond == nil {
 		return true
 	}
+	hitCount := int(lbp.TotalHitCount)
+	if lbp.HitCondPerG && goroutineID > 0 {
+		hitCount = int(lbp.HitCount[goroutineID])
+	}
 	// Evaluate the breakpoint condition.
 	switch lbp.HitCond.Op {
 	case token.EQL:
-		return int(lbp.TotalHitCount) == lbp.HitCond.Val
+		return hitCount == lbp.HitCond.Val
 	case token.NEQ:
-		return int(lbp.TotalHitCount) != lbp.HitCond.Val
+		return hitCount != lbp.HitCond.Val
 	case token.GTR:
-		return int(lbp.TotalHitCount) > lbp.HitCond.Val
+		return hitCount > lbp.HitCond.Val
 	case token.LSS:
-		return int(lbp.TotalHitCount) < lbp.HitCond.Val
+		return hitCount < lbp.HitCond.Val
 	case token.GEQ:
-		return int(lbp.TotalHitCount) >= lbp.HitCond.Val
+		return hitCount >= lbp.HitCond.Val
 	case token.LEQ:
-		return int(lbp.TotalHitCount) <= lbp.HitCond.Val
+		return hitCount <= lbp.HitCond.Val
 	case token.REM:
-		return int(lbp.TotalHitCount)%lbp.HitCond.Val == 0
+		return hitCount%lbp.HitCond.Val == 0
 	}
 	return false
 }
@@ -971,6 +977,7 @@ type LogicalBreakpoint struct {
 
 	HitCount      map[int]uint64 // Number of times a breakpoint has been reached in a certain goroutine
 	TotalHitCount uint64         // Number of times a breakpoint has been reached
+	HitCondPerG   bool           // Use per goroutine hitcount as HitCond operand, instead of total hitcount
 
 	// HitCond: if not nil the breakpoint will be triggered only if the evaluated HitCond returns
 	// true with the TotalHitCount.

pkg/terminal/command.go

@@ -451,6 +451,7 @@ The command 'on x -edit' can be used to edit the list of commands executed when
 
 	condition <breakpoint name or id> <boolean expression>.
 	condition -hitcount <breakpoint name or id> <operator> <argument>.
+	condition -per-g-hitcount <breakpoint name or id> <operator> <argument>.
 	condition -clear <breakpoint name or id>.
 
 Specifies that the breakpoint, tracepoint or watchpoint should break only if the boolean expression is true.
@@ -467,6 +468,8 @@ With the -hitcount option a condition on the breakpoint hit count can be set, th
 	condition -hitcount bp != n
 	condition -hitcount bp % n
 
+The -per-g-hitcount option works like -hitcount, but use per goroutine hitcount to compare with n.
+
 With the -clear option a condtion on the breakpoint can removed.
 	
 The '% n' form means we should stop at the breakpoint when the hitcount is a multiple of n.
@@ -1654,7 +1657,11 @@ func formatBreakpointAttrs(prefix string, bp *api.Breakpoint, includeTrace bool)
 		attrs = append(attrs, fmt.Sprintf("%scond %s", prefix, bp.Cond))
 	}
 	if bp.HitCond != "" {
-		attrs = append(attrs, fmt.Sprintf("%scond -hitcount %s", prefix, bp.HitCond))
+		if bp.HitCondPerG {
+			attrs = append(attrs, fmt.Sprintf("%scond -per-g-hitcount %s", prefix, bp.HitCond))
+		} else {
+			attrs = append(attrs, fmt.Sprintf("%scond -hitcount %s", prefix, bp.HitCond))
+		}
 	}
 	if bp.Stacktrace > 0 {
 		attrs = append(attrs, fmt.Sprintf("%sstack %d", prefix, bp.Stacktrace))
@@ -2814,11 +2821,13 @@ func conditionCmd(t *Term, ctx callContext, argstr string) error {
 		return fmt.Errorf("not enough arguments")
 	}
 
-	if args[0] == "-hitcount" {
+	hitCondPerG := args[0] == "-per-g-hitcount"
+	if args[0] == "-hitcount" || hitCondPerG {
 		// hitcount breakpoint
 
 		if ctx.Prefix == onPrefix {
 			ctx.Breakpoint.HitCond = args[1]
+			ctx.Breakpoint.HitCondPerG = hitCondPerG
 			return nil
 		}
 
@@ -2833,6 +2842,7 @@ func conditionCmd(t *Term, ctx callContext, argstr string) error {
 		}
 
 		bp.HitCond = args[1]
+		bp.HitCondPerG = hitCondPerG
 
 		return t.client.AmendBreakpoint(bp)
 	}

pkg/terminal/command_test.go

@@ -1158,6 +1158,26 @@ func TestHitCondBreakpoint(t *testing.T) {
 			t.Fatalf("wrong value of i")
 		}
 	})
+
+	withTestTerminal("condperghitcount", t, func(term *FakeTerminal) {
+		term.MustExec("break bp1 main.main:8")
+		term.MustExec("condition -per-g-hitcount bp1 == 2")
+		listIsAt(t, term, "continue", 16, -1, -1)
+		// first g hit
+		out := term.MustExec("print j")
+		t.Logf("%q", out)
+		if !strings.Contains(out, "2\n") {
+			t.Fatalf("wrong value of j")
+		}
+		term.MustExec("toggle bp1")
+		listIsAt(t, term, "continue", 16, -1, -1)
+		// second g hit
+		out = term.MustExec("print j")
+		t.Logf("%q", out)
+		if !strings.Contains(out, "2\n") {
+			t.Fatalf("wrong value of j")
+		}
+	})
 }
 
 func TestClearCondBreakpoint(t *testing.T) {

service/api/conversions.go

@@ -43,6 +43,7 @@ func ConvertLogicalBreakpoint(lbp *proc.LogicalBreakpoint) *Breakpoint {
 
 	if lbp.HitCond != nil {
 		b.HitCond = fmt.Sprintf("%s %d", lbp.HitCond.Op.String(), lbp.HitCond.Val)
+		b.HitCondPerG = lbp.HitCondPerG
 	}
 
 	var buf bytes.Buffer

service/api/types.go

@@ -92,6 +92,8 @@ type Breakpoint struct {
 	// Breakpoint hit count condition.
 	// Supported hit count conditions are "NUMBER" and "OP NUMBER".
 	HitCond string
+	// HitCondPerG use per goroutine hitcount as HitCond operand, instead of total hitcount
+	HitCondPerG bool
 
 	// Tracepoint flag, signifying this is a tracepoint.
 	Tracepoint bool `json:"continue"`

service/debugger/debugger.go

@@ -900,6 +900,7 @@ func copyLogicalBreakpointInfo(lbp *proc.LogicalBreakpoint, requested *api.Break
 			Op  token.Token
 			Val int
 		}{opTok, val}
+		lbp.HitCondPerG = requested.HitCondPerG
 	}
 
 	return nil