POC feat(symbolization): Add DWARF symbolization with debuginfod support

cmd/symbolization/main.go

@@ -0,0 +1,108 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"log"
+
+	pprof "github.com/google/pprof/profile"
+
+	"github.com/grafana/pyroscope/pkg/experiment/symbolization"
+)
+
+const (
+	debuginfodBaseURL = "https://debuginfod.elfutils.org"
+	buildID           = "2fa2055ef20fabc972d5751147e093275514b142"
+)
+
+func main() {
+	client := symbolization.NewDebuginfodClient(debuginfodBaseURL)
+
+	// Alternatively, use a local debug info file:
+	//client := &localDebuginfodClient{debugFilePath: "/path/to/your/debug/file"}
+
+	symbolizer := symbolization.NewSymbolizer(client)
+	ctx := context.Background()
+
+	_, err := client.FetchDebuginfo(buildID)
+	if err != nil {
+		log.Fatalf("Failed to fetch debug info: %v", err)
+	}
+	//defer os.Remove(debugFilePath)
+
+	// Create a request to symbolize specific addresses
+	req := symbolization.Request{
+		BuildID: buildID,
+		Mappings: []symbolization.RequestMapping{
+			{
+				Locations: []*symbolization.Location{
+					{
+						Address: 0x1500,
+						Mapping: &pprof.Mapping{},
+					},
+					{
+						Address: 0x3c5a,
+						Mapping: &pprof.Mapping{},
+					},
+					{
+						Address: 0x2745,
+						Mapping: &pprof.Mapping{},
+					},
+				},
+			},
+		},
+	}
+
+	if err := symbolizer.Symbolize(ctx, req); err != nil {
+		log.Fatalf("Failed to symbolize: %v", err)
+	}
+
+	fmt.Println("Symbolization Results:")
+	fmt.Printf("Build ID: %s\n", buildID)
+	fmt.Println("----------------------------------------")
+
+	for i, mapping := range req.Mappings {
+		fmt.Printf("Mapping #%d:\n", i+1)
+		for _, loc := range mapping.Locations {
+			fmt.Printf("\nAddress: 0x%x\n", loc.Address)
+			if len(loc.Lines) == 0 {
+				fmt.Println("  No symbolization information found")
+				continue
+			}
+
+			for j, line := range loc.Lines {
+				fmt.Printf("  Line %d:\n", j+1)
+				if line.Function != nil {
+					fmt.Printf("    Function:   %s\n", line.Function.Name)
+					fmt.Printf("    File:       %s\n", line.Function.Filename)
+					fmt.Printf("    Line:       %d\n", line.Line)
+					fmt.Printf("    StartLine:  %d\n", line.Function.StartLine)
+				} else {
+					fmt.Println("    No function information available")
+				}
+			}
+			fmt.Println("----------------------------------------")
+		}
+	}
+
+	// Alternatively: Symbolize all addresses in the binary
+	// Note: Comment out the above specific symbolization when using this
+	// as it's a different approach meant for exploring all available symbols
+	//if err := symbolizer.SymbolizeAll(ctx, buildID); err != nil {
+	//	log.Fatalf("Failed to symbolize all addresses: %v", err)
+	//}
+
+	fmt.Println("\nSymbolization completed successfully.")
+}
+
+// localDebuginfodClient provides a way to use local debug info files instead of fetching from a server
+//
+//nolint:all
+type localDebuginfodClient struct {
+	debugFilePath string
+}
+
+//nolint:all
+func (c *localDebuginfodClient) FetchDebuginfo(buildID string) (string, error) {
+	return c.debugFilePath, nil
+}

go.mod

@@ -19,6 +19,7 @@ require (
 	github.com/felixge/fgprof v0.9.4-0.20221116204635-ececf7638e93
 	github.com/felixge/httpsnoop v1.0.4
 	github.com/fsnotify/fsnotify v1.7.0
+	github.com/go-delve/delve v1.23.1
 	github.com/go-kit/log v0.2.1
 	github.com/gogo/protobuf v1.3.2
 	github.com/gogo/status v1.1.1

go.sum

@@ -241,6 +241,8 @@ github.com/fsnotify/fsnotify v1.7.0 h1:8JEhPFa5W2WU7YfeZzPNqzMP6Lwt7L2715Ggo0nos
 github.com/fsnotify/fsnotify v1.7.0/go.mod h1:40Bi/Hjc2AVfZrqy+aj+yEI+/bRxZnMJyTJwOpGvigM=
 github.com/fullstorydev/emulators/storage v0.0.0-20240401123056-edc69752f474 h1:TufioMBjkJ6/Oqmlye/ReuxHFS35HyLmypj/BNy/8GY=
 github.com/fullstorydev/emulators/storage v0.0.0-20240401123056-edc69752f474/go.mod h1:PQwxF4UU8wuL+srGxr3BOhIW5zXqgucwVlO/nPZLsxw=
+github.com/go-delve/delve v1.23.1 h1:MtZ13ppptttkqSuvVnwJ5CPhIAzDiOwRrYuCk3ES7fU=
+github.com/go-delve/delve v1.23.1/go.mod h1:S3SLuEE2mn7wipKilTvk1p9HdTMnXXElcEpiZ+VcuqU=
 github.com/go-fonts/dejavu v0.3.4 h1:Qqyx9IOs5CQFxyWTdvddeWzrX0VNwUAvbmAzL0fpjbc=
 github.com/go-fonts/dejavu v0.3.4/go.mod h1:D1z0DglIz+lmpeNYMYlxW4r22IhcdOYnt+R3PShU/Kg=
 github.com/go-fonts/latin-modern v0.3.3 h1:g2xNgI8yzdNzIVm+qvbMryB6yGPe0pSMss8QT3QwlJ0=

go.work.sum

@@ -628,13 +628,21 @@ github.com/containerd/log v0.1.0/go.mod h1:VRRf09a7mHDIRezVKTRCrOq78v577GXq3bSa3
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+github.com/cosiner/argv v0.1.0 h1:BVDiEL32lwHukgJKP87btEPenzrrHUjajs/8yzaqcXg=
+github.com/cosiner/argv v0.1.0/go.mod h1:EusR6TucWKX+zFgtdUsKT2Cvg45K5rtpCcWz4hK06d8=
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 github.com/davecgh/go-xdr v0.0.0-20161123171359-e6a2ba005892/go.mod h1:CTDl0pzVzE5DEzZhPfvhY/9sPFMQIxaJ9VAMs9AagrE=
+github.com/derekparker/trie v0.0.0-20230829180723-39f4de51ef7d h1:hUWoLdw5kvo2xCsqlsIBMvWUc1QCSsCYD2J2+Fg6YoU=
+github.com/derekparker/trie v0.0.0-20230829180723-39f4de51ef7d/go.mod h1:C7Es+DLenIpPc9J6IYw4jrK0h7S9bKj4DNl8+KxGEXU=
 github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f h1:lO4WD4F/rVNCu3HqELle0jiPLLBs70cWOduZpkS1E78=
 github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f/go.mod h1:cuUVRXasLTGF7a8hSLbxyZXjz+1KgoB3wDUb6vlszIc=
 github.com/digitalocean/godo v1.104.1/go.mod h1:VAI/L5YDzMuPRU01lEEUSQ/sp5Z//1HnnFv/RBTEdbg=
@@ -658,6 +666,8 @@ github.com/franela/goreq v0.0.0-20171204163338-bcd34c9993f8/go.mod h1:ZhphrRTfi2
 github.com/frankban/quicktest v1.14.3/go.mod h1:mgiwOwqx65TmIk1wJ6Q7wvnVMocbUorkibMOrVTHZps=
 github.com/ghodss/yaml v1.0.1-0.20190212211648-25d852aebe32 h1:Mn26/9ZMNWSw9C9ERFA1PUxfmGpolnw2v0bKOREu5ew=
 github.com/ghodss/yaml v1.0.1-0.20190212211648-25d852aebe32/go.mod h1:GIjDIg/heH5DOkXY3YJ/wNhfHsQHoXGjl8G8amsYQ1I=
+github.com/go-delve/liner v1.2.3-0.20231231155935-4726ab1d7f62 h1:IGtvsNyIuRjl04XAOFGACozgUD7A82UffYxZt4DWbvA=
+github.com/go-delve/liner v1.2.3-0.20231231155935-4726ab1d7f62/go.mod h1:biJCRbqp51wS+I92HMqn5H8/A0PAhxn2vyOT+JqhiGI=
 github.com/go-fonts/stix v0.2.2 h1:v9krocr13J1llaOHLEol1eaHsv8S43UuFX/1bFgEJJ4=
 github.com/go-fonts/stix v0.2.2/go.mod h1:SUxggC9dxd/Q+rb5PkJuvfvTbOPtNc2Qaua00fIp9iU=
 github.com/go-gl/glfw v0.0.0-20190409004039-e6da0acd62b1 h1:QbL/5oDUmRBzO9/Z7Seo6zf912W/a6Sr4Eu0G/3Jho0=
@@ -739,6 +749,8 @@ github.com/google/btree v1.0.1/go.mod h1:xXMiIv4Fb/0kKde4SpL7qlzvu5cMJDRkFDxJfI9
 github.com/google/flatbuffers v2.0.8+incompatible h1:ivUb1cGomAB101ZM1T0nOiWz9pSrTMoa9+EiY7igmkM=
 github.com/google/flatbuffers v2.0.8+incompatible/go.mod h1:1AeVuKshWv4vARoZatz6mlQ0JxURH0Kv5+zNeJKJCa8=
 github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
+github.com/google/go-dap v0.12.0 h1:rVcjv3SyMIrpaOoTAdFDyHs99CwVOItIJGKLQFQhNeM=
+github.com/google/go-dap v0.12.0/go.mod h1:tNjCASCm5cqePi/RVXXWEVqtnNLV1KTWtYOqu6rZNzc=
 github.com/google/go-pkcs11 v0.2.1-0.20230907215043-c6f79328ddf9 h1:OF1IPgv+F4NmqmJ98KTjdN97Vs1JxDPB3vbmYzV2dpk=
 github.com/google/go-pkcs11 v0.2.1-0.20230907215043-c6f79328ddf9/go.mod h1:6eQoGcuNJpa7jnd5pMGdkSaQpNDYvPlXWMcjXXThLlY=
 github.com/google/pprof v0.0.0-20230926050212-f7f687d19a98/go.mod h1:czg5+yv1E0ZGTi6S6vVK1mke0fV+FaUhNGcd6VRS9Ik=
@@ -793,6 +805,8 @@ github.com/hudl/fargo v1.4.0/go.mod h1:9Ai6uvFy5fQNq6VPKtg+Ceq1+eTY4nKUlR2JElEOc
 github.com/iancoleman/strcase v0.2.0 h1:05I4QRnGpI0m37iZQRuskXh+w77mr6Z41lwQzuHLwW0=
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+github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
+github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
 github.com/influxdata/influxdb1-client v0.0.0-20200827194710-b269163b24ab h1:HqW4xhhynfjrtEiiSGcQUd6vrK23iMam1FO8rI7mwig=
 github.com/influxdata/influxdb1-client v0.0.0-20200827194710-b269163b24ab/go.mod h1:qj24IKcXYK6Iy9ceXlo3Tc+vtHo9lIhSX5JddghvEPo=
 github.com/ionos-cloud/sdk-go/v6 v6.1.9/go.mod h1:EzEgRIDxBELvfoa/uBN0kOQaqovLjUWEB7iW4/Q+t4k=
@@ -963,6 +977,8 @@ github.com/rs/cors v1.10.1 h1:L0uuZVXIKlI1SShY2nhFfo44TYvDPQ1w4oFkUJNfhyo=
 github.com/rs/cors v1.10.1/go.mod h1:XyqrcTp5zjWr1wsJ8PIRZssZ8b/WMcMf71DJnit4EMU=
 github.com/russross/blackfriday v1.6.0 h1:KqfZb0pUVN2lYqZUYRddxF4OR8ZMURnJIG5Y3VRLtww=
 github.com/russross/blackfriday v1.6.0/go.mod h1:ti0ldHuxg49ri4ksnFxlkCfN+hvslNlmVHqNRXXJNAY=
+github.com/russross/blackfriday/v2 v2.1.0 h1:JIOH55/0cWyOuilr9/qlrm0BSXldqnqwMsf35Ld67mk=
+github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/ruudk/golang-pdf417 v0.0.0-20201230142125-a7e3863a1245 h1:K1Xf3bKttbF+koVGaX5xngRIZ5bVjbmPnaxE/dR08uY=
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 github.com/ryanuber/columnize v2.1.0+incompatible h1:j1Wcmh8OrK4Q7GXY+V7SVSY8nUWQxHW5TkBe7YUl+2s=
@@ -993,6 +1009,8 @@ github.com/spf13/cast v1.3.1/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkU
 github.com/spf13/cast v1.5.0 h1:rj3WzYc11XZaIZMPKmwP96zkFEnnAmV8s6XbB2aY32w=
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+github.com/spf13/cobra v1.7.0 h1:hyqWnYt1ZQShIddO5kBpj3vu05/++x6tJ6dg8EC572I=
+github.com/spf13/cobra v1.7.0/go.mod h1:uLxZILRyS/50WlhOIKD7W6V5bgeIt+4sICxh6uRMrb0=
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@@ -1082,9 +1100,13 @@ go.opentelemetry.io/otel/trace v1.17.0/go.mod h1:I/4vKTgFclIsXRVucpH25X0mpFSczM7
 go.opentelemetry.io/otel/trace v1.21.0/go.mod h1:LGbsEB0f9LGjN+OZaQQ26sohbOmiMR+BaslueVtS/qQ=
 go.opentelemetry.io/otel/trace v1.22.0/go.mod h1:RbbHXVqKES9QhzZq/fE5UnOSILqRt40a21sPw2He1xo=
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+go.starlark.net v0.0.0-20231101134539-556fd59b42f6 h1:+eC0F/k4aBLC4szgOcjd7bDTEnpxADJyWJE0yowgM3E=
+go.starlark.net v0.0.0-20231101134539-556fd59b42f6/go.mod h1:LcLNIzVOMp4oV+uusnpk+VU+SzXaJakUuBjoCSWH5dM=
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pkg/experiment/symbolization/addrmapper.go

@@ -0,0 +1,190 @@
+package symbolization
+
+import (
+	"debug/elf"
+	"fmt"
+)
+
+// BinaryLayout contains the information needed to translate between runtime addresses
+// and the addresses in the debug information. This is necessary because:
+// 1. Executables (ET_EXEC) use fixed addresses but may need segment offset adjustments
+// 2. Shared libraries (ET_DYN) can be loaded at any address, requiring base address calculations
+// 3. Relocatable files (ET_REL) need special handling for their relocations
+type BinaryLayout struct {
+	ElfType        uint16
+	ProgramHeaders []MemoryRegion
+}
+
+// MemoryRegion represents a loadable segment in the ELF file.
+// These segments define how the program should be loaded into memory:
+// - Off: where the segment data starts in the file
+// - Vaddr: the virtual address where the segment should be loaded
+// - Memsz: how much memory the segment occupies when loaded
+type MemoryRegion struct {
+	Off    uint64 // File offset
+	Vaddr  uint64 // Virtual address
+	Filesz uint64 // Size in file
+	Memsz  uint64 // Size in memory (may be larger than Filesz due to .bss)
+	Type   uint32
+}
+
+func ExecutableInfoFromELF(f *elf.File) (*BinaryLayout, error) {
+	loadableSegments := make([]MemoryRegion, 0, len(f.Progs))
+	for _, segment := range f.Progs {
+		if segment.Type == elf.PT_LOAD {
+			loadableSegments = append(loadableSegments, MemoryRegion{
+				Off:    segment.Off,
+				Vaddr:  segment.Vaddr,
+				Filesz: segment.Filesz,
+				Memsz:  segment.Memsz,
+				Type:   uint32(segment.Type),
+			})
+		}
+	}
+
+	return &BinaryLayout{
+		ElfType:        uint16(f.Type),
+		ProgramHeaders: loadableSegments,
+	}, nil
+}
+
+// MapRuntimeAddress translates a runtime address to its corresponding address
+// in the debug information. This translation is necessary because:
+// - The program might be loaded at a different address than it was linked for
+// - Different segments might need different adjustments
+// - Various ELF types (EXEC, DYN, REL) handle addressing differently
+func MapRuntimeAddress(runtimeAddr uint64, ei *BinaryLayout, m Mapping) (uint64, error) {
+	baseOffset, err := CalculateBase(ei, m, runtimeAddr)
+	if err != nil {
+		return runtimeAddr, fmt.Errorf("calculate base offset: %w", err)
+	}
+
+	return runtimeAddr - baseOffset, nil
+}
+
+// CalculateBase determines the base address adjustment needed for address translation.
+// The calculation varies depending on the ELF type:
+// - ET_EXEC: Uses fixed addresses with potential segment adjustments
+// - ET_DYN: Can be loaded anywhere, needs runtime base address adjustment
+// - ET_REL: Requires relocation processing
+func CalculateBase(ei *BinaryLayout, m Mapping, addr uint64) (uint64, error) {
+	segment, err := ei.FindProgramHeader(m, addr)
+	if err != nil {
+		return 0, fmt.Errorf("find program segment: %w", err)
+	}
+
+	if segment == nil {
+		return 0, nil
+	}
+
+	// Handle special case where mapping spans entire address space
+	if m.Start == 0 && m.Offset == 0 && (m.Limit == ^uint64(0) || m.Limit == 0) {
+		return 0, nil
+	}
+
+	switch elf.Type(ei.ElfType) {
+	case elf.ET_EXEC:
+		return calculateExecBase(m, segment)
+	case elf.ET_REL:
+		return calculateRelocatableBase(m)
+	case elf.ET_DYN:
+		return calculateDynamicBase(m, segment)
+	}
+
+	return 0, fmt.Errorf("unsupported ELF type: %v", elf.Type(ei.ElfType))
+}
+
+// FindProgramHeader finds the program header containing the given address.
+// It returns nil if no header is found.
+func (ei *BinaryLayout) FindProgramHeader(m Mapping, addr uint64) (*MemoryRegion, error) {
+	// Special case: if mapping is empty (all zeros), just look for any header containing the address
+	if m.Start == 0 && m.Limit == 0 {
+		for i := range ei.ProgramHeaders {
+			h := &ei.ProgramHeaders[i]
+			if h.Type == uint32(elf.PT_LOAD) {
+				if h.Vaddr <= addr && addr < h.Vaddr+h.Memsz {
+					return h, nil
+				}
+			}
+		}
+		return nil, nil
+	}
+
+	// Fast path: if address is invalid or outside reasonable range
+	if m.Start >= m.Limit {
+		return nil, fmt.Errorf("invalid mapping range: start %x >= limit %x", m.Start, m.Limit)
+	}
+
+	// Special case: kernel addresses or very high addresses
+	if m.Limit >= (1 << 63) {
+		return nil, nil
+	}
+
+	// No loadable segments
+	if len(ei.ProgramHeaders) == 0 {
+		return nil, nil
+	}
+
+	// Calculate file offset from the address
+	fileOffset := addr - m.Start + m.Offset
+
+	// Find all headers that could contain this address
+	var candidateHeaders []*MemoryRegion
+	for i := range ei.ProgramHeaders {
+		h := &ei.ProgramHeaders[i]
+		if h.Type != uint32(elf.PT_LOAD) {
+			continue
+		}
+
+		// Check if the file offset falls within this segment
+		if fileOffset >= h.Off && fileOffset < h.Off+h.Memsz {
+			candidateHeaders = append(candidateHeaders, h)
+		}
+	}
+
+	// No matching headers found
+	if len(candidateHeaders) == 0 {
+		return nil, nil
+	}
+
+	// If only one header matches, return it
+	if len(candidateHeaders) == 1 {
+		return candidateHeaders[0], nil
+	}
+
+	// Multiple headers - need to select the most appropriate one
+	// Choose the one with the closest starting address to our target
+	var bestHeader *MemoryRegion
+	bestDistance := uint64(^uint64(0)) // Max uint64 as initial distance
+
+	for _, h := range candidateHeaders {
+		distance := addr - h.Vaddr
+		if distance < bestDistance {
+			bestDistance = distance
+			bestHeader = h
+		}
+	}
+
+	return bestHeader, nil
+}
+
+func calculateExecBase(m Mapping, h *MemoryRegion) (uint64, error) {
+	if h == nil {
+		return 0, nil
+	}
+	return m.Start - m.Offset + h.Off - h.Vaddr, nil
+}
+
+func calculateRelocatableBase(m Mapping) (uint64, error) {
+	if m.Offset != 0 {
+		return 0, fmt.Errorf("relocatable files with non-zero offset not supported")
+	}
+	return m.Start, nil
+}
+
+func calculateDynamicBase(m Mapping, h *MemoryRegion) (uint64, error) {
+	if h == nil {
+		return m.Start - m.Offset, nil
+	}
+	return m.Start - m.Offset + h.Off - h.Vaddr, nil
+}