cache: mark cache panic messages as safe from redaction

Previously, panic messages in the cache package containing ref counts
were being redacted when surfaced in CockroachDB logs, making it
impossible to diagnose cache value ref counting issues.

Wrap the panic format strings with errors.AssertionFailedf() so the
full message (including the ref count) is visible in redacted logs.

Informs: cockroachdb/cockroach#164740.

Co-Authored-By: roachdev-claude <roachdev-claude-bot@cockroachlabs.com>

Author: annrpom

internal/cache/cache.go

@@ -15,6 +15,7 @@ import (
 	"sync/atomic"
 	"time"
 
+	"github.com/cockroachdb/errors"
 	"github.com/cockroachdb/pebble/internal/base"
 	"github.com/cockroachdb/pebble/internal/invariants"
 	"github.com/cockroachdb/pebble/internal/metricsutil"
@@ -327,7 +328,7 @@ func (c *Handle) GetWithReadHandle(
 // REQUIRES: value.refs() == 1
 func (c *Handle) Set(fileNum base.DiskFileNum, offset uint64, value *Value) {
 	if n := value.refs(); n != 1 {
-		panic(fmt.Sprintf("pebble: Value has already been added to the cache: refs=%d", n))
+		panic(errors.AssertionFailedf("pebble: Value has already been added to the cache: refs=%d", n))
 	}
 	k := makeKey(c.id, fileNum, offset)
 	c.cache.getShard(k).set(k, value, false /*markAccessed*/)

internal/cache/read_shard.go

@@ -6,10 +6,10 @@ package cache
 
 import (
 	"context"
-	"fmt"
 	"sync"
 	"time"
 
+	"github.com/cockroachdb/errors"
 	"github.com/cockroachdb/pebble/internal/invariants"
 	"github.com/cockroachdb/swiss"
 )
@@ -295,7 +295,7 @@ func (e *readEntry) unrefAndTryRemoveFromMap() {
 
 func (e *readEntry) setReadValue(v *Value) {
 	if n := v.refs(); n != 1 {
-		panic(fmt.Sprintf("pebble: Value has already been added to the cache: refs=%d", n))
+		panic(errors.AssertionFailedf("pebble: Value has already been added to the cache: refs=%d", n))
 	}
 	concurrentRequesters := false
 	e.mu.Lock()

internal/cache/value.go

@@ -10,6 +10,7 @@ import (
 	"os"
 	"unsafe"
 
+	"github.com/cockroachdb/errors"
 	"github.com/cockroachdb/pebble/internal/buildtags"
 	"github.com/cockroachdb/pebble/internal/invariants"
 	"github.com/cockroachdb/pebble/internal/manual"
@@ -143,7 +144,7 @@ func (v *Value) Release() {
 // Free. Do not call Free on a value that has been added to the cache.
 func Free(v *Value) {
 	if n := v.refs(); n > 1 {
-		panic(fmt.Sprintf("pebble: Value has been added to the cache: refs=%d", n))
+		panic(errors.AssertionFailedf("pebble: Value has been added to the cache: refs=%d", n))
 	}
 	v.Release()
 }