syz-manager: better encapsulate report generator

Avoid global variables and implicit dependencies on previous initialization.

4 files changed, 38 insertions, 36 deletions

diff --git a/pkg/cover/report.go b/pkg/cover/report.go
index 14c0b7422..e50e11d13 100644
--- a/pkg/cover/report.go
+++ b/pkg/cover/report.go
@@ -32,6 +32,9 @@ var (
 )
 
 func MakeReportGenerator(target *targets.Target, vm, objDir, srcDir, buildDir string) (*ReportGenerator, error) {
+	if objDir == "" {
+		return nil, fmt.Errorf("kernel obj directory is not specified")
+	}
 	impl, err := backend.Make(target, vm, objDir)
 	if err != nil {
 		return nil, err
diff --git a/syz-manager/cover.go b/syz-manager/cover.go
index 39f2ed001..f5ca86631 100644
--- a/syz-manager/cover.go
+++ b/syz-manager/cover.go
@@ -4,36 +4,30 @@
 package main
 
 import (
-	"fmt"
 	"sync"
 
 	"github.com/google/syzkaller/pkg/cover"
+	"github.com/google/syzkaller/pkg/log"
 	"github.com/google/syzkaller/pkg/mgrconfig"
-	"github.com/google/syzkaller/sys/targets"
 )
 
-var (
-	initCoverOnce   sync.Once
-	initCoverError  error
-	reportGenerator *cover.ReportGenerator
-)
-
-func initCover(cfg *mgrconfig.Config) error {
-	initCoverOnce.Do(func() {
-		if cfg.KernelObj == "" {
-			initCoverError = fmt.Errorf("kernel_obj is not specified")
-			return
-		}
-		reportGenerator, initCoverError = cover.MakeReportGenerator(
-			cfg.SysTarget, cfg.Type, cfg.KernelObj, cfg.KernelSrc, cfg.KernelBuildSrc)
-	})
-	return initCoverError
-}
+var getReportGenerator = func() func(cfg *mgrconfig.Config) (*cover.ReportGenerator, error) {
+	var once sync.Once
+	var rg *cover.ReportGenerator
+	var err error
+	return func(cfg *mgrconfig.Config) (*cover.ReportGenerator, error) {
+		once.Do(func() {
+			log.Logf(0, "initializing coverage information...")
+			rg, err = cover.MakeReportGenerator(cfg.SysTarget, cfg.Type, cfg.KernelObj, cfg.KernelSrc, cfg.KernelBuildSrc)
+		})
+		return rg, err
+	}
+}()
 
-func coverToPCs(target *targets.Target, cov []uint32) []uint64 {
+func coverToPCs(rg *cover.ReportGenerator, cov []uint32) []uint64 {
 	pcs := make([]uint64, 0, len(cov))
 	for _, pc := range cov {
-		pcs = append(pcs, reportGenerator.RestorePC(pc))
+		pcs = append(pcs, rg.RestorePC(pc))
 	}
 	return pcs
 }
diff --git a/syz-manager/covfilter.go b/syz-manager/covfilter.go
index 5b252603e..db4c5a64f 100644
--- a/syz-manager/covfilter.go
+++ b/syz-manager/covfilter.go
@@ -13,6 +13,7 @@ import (
 	"sort"
 	"strconv"
 
+	"github.com/google/syzkaller/pkg/cover"
 	"github.com/google/syzkaller/pkg/log"
 	"github.com/google/syzkaller/pkg/mgrconfig"
 	"github.com/google/syzkaller/pkg/osutil"
@@ -23,11 +24,11 @@ func createCoverageFilter(cfg *mgrconfig.Config) (string, map[uint32]uint32, err
 	pcs := make(map[uint32]uint32)
 	filter := &cfg.CovFilter
 	if len(filter.Files) != 0 || len(filter.Functions) != 0 {
-		log.Logf(0, "initializing coverage information...")
-		if err := initCover(cfg); err != nil {
+		rg, err := getReportGenerator(cfg)
+		if err != nil {
 			return "", nil, err
 		}
-		if err := initFilesFuncs(pcs, filter.Files, filter.Functions); err != nil {
+		if err := initFilesFuncs(pcs, filter.Files, filter.Functions, rg); err != nil {
 			return "", nil, err
 		}
 	}
@@ -48,7 +49,7 @@ func createCoverageFilter(cfg *mgrconfig.Config) (string, map[uint32]uint32, err
 	return filename, pcs, nil
 }
 
-func initFilesFuncs(pcs map[uint32]uint32, files, funcs []string) error {
+func initFilesFuncs(pcs map[uint32]uint32, files, funcs []string, rg *cover.ReportGenerator) error {
 	funcsRegexp, err := compileRegexps(funcs)
 	if err != nil {
 		return err
@@ -59,7 +60,7 @@ func initFilesFuncs(pcs map[uint32]uint32, files, funcs []string) error {
 	}
 	fileDedup := make(map[string]bool)
 	used := make(map[*regexp.Regexp][]string)
-	for _, sym := range reportGenerator.Symbols {
+	for _, sym := range rg.Symbols {
 		matched := false
 		for _, re := range funcsRegexp {
 			if re.MatchString(sym.Name) {
diff --git a/syz-manager/html.go b/syz-manager/html.go
index 24126adb5..0b606f099 100644
--- a/syz-manager/html.go
+++ b/syz-manager/html.go
@@ -214,22 +214,24 @@ func (mgr *Manager) httpCover(w http.ResponseWriter, r *http.Request) {
 	}
 	// Note: initCover is executed without mgr.mu because it takes very long time
 	// (but it only reads config and it protected by initCoverOnce).
-	if err := initCover(mgr.cfg); err != nil {
+	rg, err := getReportGenerator(mgr.cfg)
+	if err != nil {
 		http.Error(w, fmt.Sprintf("failed to generate coverage profile: %v", err), http.StatusInternalServerError)
 		return
 	}
 	mgr.mu.Lock()
 	defer mgr.mu.Unlock()
-	mgr.httpCoverCover(w, r, reportGenerator.DoHTML)
+	mgr.httpCoverCover(w, r, rg, rg.DoHTML)
 }
 
-func (mgr *Manager) httpCoverCover(w http.ResponseWriter, r *http.Request, do func(io.Writer, []cover.Prog) error) {
+func (mgr *Manager) httpCoverCover(w http.ResponseWriter, r *http.Request,
+	rg *cover.ReportGenerator, do func(io.Writer, []cover.Prog) error) {
 	var progs []cover.Prog
 	if sig := r.FormValue("input"); sig != "" {
 		inp := mgr.corpus[sig]
 		progs = append(progs, cover.Prog{
 			Data: string(inp.Prog),
-			PCs:  coverToPCs(mgr.sysTarget, inp.Cover),
+			PCs:  coverToPCs(rg, inp.Cover),
 		})
 	} else {
 		call := r.FormValue("call")
@@ -239,7 +241,7 @@ func (mgr *Manager) httpCoverCover(w http.ResponseWriter, r *http.Request, do fu
 			}
 			progs = append(progs, cover.Prog{
 				Data: string(inp.Prog),
-				PCs:  coverToPCs(mgr.sysTarget, inp.Cover),
+				PCs:  coverToPCs(rg, inp.Cover),
 			})
 		}
 	}
@@ -286,13 +288,14 @@ func (mgr *Manager) httpFuncCover(w http.ResponseWriter, r *http.Request) {
 		http.Error(w, "coverage is not enabled", http.StatusInternalServerError)
 		return
 	}
-	if err := initCover(mgr.cfg); err != nil {
+	rg, err := getReportGenerator(mgr.cfg)
+	if err != nil {
 		http.Error(w, fmt.Sprintf("failed to generate coverage profile: %v", err), http.StatusInternalServerError)
 		return
 	}
 	mgr.mu.Lock()
 	defer mgr.mu.Unlock()
-	mgr.httpCoverCover(w, r, reportGenerator.DoCSV)
+	mgr.httpCoverCover(w, r, rg, rg.DoCSV)
 }
 
 func (mgr *Manager) httpPrio(w http.ResponseWriter, r *http.Request) {
@@ -392,8 +395,9 @@ func (mgr *Manager) httpReport(w http.ResponseWriter, r *http.Request) {
 func (mgr *Manager) httpRawCover(w http.ResponseWriter, r *http.Request) {
 	// Note: initCover is executed without mgr.mu because it takes very long time
 	// (but it only reads config and it protected by initCoverOnce).
-	if err := initCover(mgr.cfg); err != nil {
-		http.Error(w, initCoverError.Error(), http.StatusInternalServerError)
+	rg, err := getReportGenerator(mgr.cfg)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
 		return
 	}
 	mgr.mu.Lock()
@@ -403,7 +407,7 @@ func (mgr *Manager) httpRawCover(w http.ResponseWriter, r *http.Request) {
 	for _, inp := range mgr.corpus {
 		cov.Merge(inp.Cover)
 	}
-	pcs := coverToPCs(mgr.sysTarget, cov.Serialize())
+	pcs := coverToPCs(rg, cov.Serialize())
 	sort.Slice(pcs, func(i, j int) bool {
 		return pcs[i] < pcs[j]
 	})