fix: handle non-pointer values in the flag parser (#3720)

pkg/experiment/compactor/compaction_worker.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"runtime"
 	"strconv"
 	"strings"
 	"sync"
@@ -19,6 +20,7 @@ import (
 	"github.com/opentracing/opentracing-go"
 	"github.com/pkg/errors"
 	"github.com/prometheus/client_golang/prometheus"
+	_ "go.uber.org/automaxprocs"
 	"golang.org/x/sync/errgroup"
 
 	metastorev1 "github.com/grafana/pyroscope/api/gen/proto/go/metastore/v1"
@@ -47,17 +49,17 @@ type Worker struct {
 }
 
 type Config struct {
-	JobConcurrency  util.ConcurrencyLimit `yaml:"job_capacity"`
-	JobPollInterval time.Duration         `yaml:"job_poll_interval"`
-	SmallObjectSize int                   `yaml:"small_object_size_bytes"`
-	TempDir         string                `yaml:"temp_dir"`
-	RequestTimeout  time.Duration         `yaml:"request_timeout"`
+	JobConcurrency  int           `yaml:"job_capacity"`
+	JobPollInterval time.Duration `yaml:"job_poll_interval"`
+	SmallObjectSize int           `yaml:"small_object_size_bytes"`
+	TempDir         string        `yaml:"temp_dir"`
+	RequestTimeout  time.Duration `yaml:"request_timeout"`
 }
 
 func (cfg *Config) RegisterFlags(f *flag.FlagSet) {
 	const prefix = "compaction-worker."
 	tempdir := filepath.Join(os.TempDir(), "pyroscope-compactor")
-	f.TextVar(&cfg.JobConcurrency, prefix+"job-concurrency", util.GoMaxProcsConcurrencyLimit(), "Number of concurrent jobs compaction worker will run. Defaults to the number of CPU cores.")
+	f.IntVar(&cfg.JobConcurrency, prefix+"job-concurrency", 0, "Number of concurrent jobs compaction worker will run. Defaults to the number of CPU cores.")
 	f.DurationVar(&cfg.JobPollInterval, prefix+"job-poll-interval", 5*time.Second, "Interval between job requests")
 	f.DurationVar(&cfg.RequestTimeout, prefix+"request-timeout", 5*time.Second, "Job request timeout.")
 	f.IntVar(&cfg.SmallObjectSize, prefix+"small-object-size-bytes", 8<<20, "Size of the object that can be loaded in memory.")
@@ -95,7 +97,10 @@ func New(
 		storage: storage,
 		metrics: newMetrics(reg),
 	}
-	w.threads = int(config.JobConcurrency)
+	w.threads = config.JobConcurrency
+	if w.threads < 1 {
+		w.threads = runtime.GOMAXPROCS(-1)
+	}
 	w.queue = make(chan *compactionJob, 2*w.threads)
 	w.jobs = make(map[string]*compactionJob, 2*w.threads)
 	w.capacity.Store(int32(w.threads))

tools/doc-generator/parse/parser.go

@@ -13,6 +13,7 @@ import (
 	"strings"
 	"time"
 	"unicode"
+	"unsafe"
 
 	"github.com/go-kit/log"
 	"github.com/grafana/dskit/flagext"
@@ -115,8 +116,16 @@ func Flags(cfg flagext.Registerer, logger log.Logger) map[uintptr]*flag.Flag {
 			return
 		}
 
-		ptr := reflect.ValueOf(f.Value).Pointer()
-		flags[ptr] = f
+		val := reflect.ValueOf(f.Value)
+		if val.Kind() == reflect.Ptr {
+			flags[val.Pointer()] = f
+		} else if val.CanAddr() {
+			flags[val.UnsafeAddr()] = f
+		} else if val.CanInterface() {
+			flags[uintptr(unsafe.Pointer(&f.Value))] = f
+		} else {
+			panic("cannot get pointer to flag value")
+		}
 	})
 
 	return flags