perf tools: add support for reading object code

index b7b4049..f5af192 100644
@@ -100,6 +100,10 @@ static struct test {
 	},
 #endif
 	{
+		.desc = "Test object code reading",
+		.func = test__code_reading,
+	},
+	{
 		.func = NULL,
 	},
 };

509 lines not on this page · raw message

index d22202a..c748f53 100644
@@ -36,5 +36,6 @@ int test__bp_signal_overflow(void);
 int test__task_exit(void);
 int test__sw_clock_freq(void);
 int test__perf_time_to_tsc(void);
+int test__code_reading(void);
 
 #endif /* TESTS_H */

index 1d8de2e..f012a98 100644
@@ -206,7 +206,7 @@ static int perf_event__inject_buildid(struct perf_tool *tool,
 	}
 
 	thread__find_addr_map(thread, machine, cpumode, MAP__FUNCTION,
-			      event->ip.ip, &al);
+			      event->ip.ip, &al, NULL);
 
 	if (al.map != NULL) {
 		if (!al.map->dso->hit) {

index 1cad370..cd616ff 100644
@@ -341,10 +341,10 @@ static void print_sample_addr(union perf_event *event,
 		return;
 
 	thread__find_addr_map(thread, machine, cpumode, MAP__FUNCTION,
-			      sample->addr, &al);
+			      sample->addr, &al, NULL);
 	if (!al.map)
 		thread__find_addr_map(thread, machine, cpumode, MAP__VARIABLE,
-				      sample->addr, &al);
+				      sample->addr, &al, NULL);
 
 	al.cpu = sample->cpu;
 	al.sym = NULL;

index 28bee62..0c7b052 100644
@@ -138,7 +138,7 @@ static int read_object_code(u64 addr, size_t len, u8 cpumode,
 	pr_debug("Reading object code for memory address: %#"PRIx64"\n", addr);
 
 	thread__find_addr_map(thread, machine, cpumode, MAP__FUNCTION, addr,
-			      &al);
+			      &al, NULL);
 	if (!al.map || !al.map->dso) {
 		pr_debug("thread__find_addr_map failed\n");
 		return -1;

index 5295625..3a0f508 100644
@@ -33,7 +33,7 @@ int build_id__mark_dso_hit(struct perf_tool *tool __maybe_unused,
 	}
 
 	thread__find_addr_map(thread, machine, cpumode, MAP__FUNCTION,
-			      event->ip.ip, &al);
+			      event->ip.ip, &al, NULL);
 
 	if (al.map != NULL)
 		al.map->dso->hit = 1;

index 9541270..cc7c0c9 100644
@@ -592,9 +592,10 @@ int perf_event__process(struct perf_tool *tool __maybe_unused,
 void thread__find_addr_map(struct thread *self,
 			   struct machine *machine, u8 cpumode,
 			   enum map_type type, u64 addr,
-			   struct addr_location *al)
+			   struct addr_location *al, symbol_filter_t filter)
 {
 	struct map_groups *mg = &self->mg;
+	bool load_map = false;
 
 	al->thread = self;
 	al->addr = addr;

@@ -609,11 +610,13 @@ void thread__find_addr_map(struct thread *self,
 	if (cpumode == PERF_RECORD_MISC_KERNEL && perf_host) {
 		al->level = 'k';
 		mg = &machine->kmaps;
+		load_map = true;
 	} else if (cpumode == PERF_RECORD_MISC_USER && perf_host) {
 		al->level = '.';
 	} else if (cpumode == PERF_RECORD_MISC_GUEST_KERNEL && perf_guest) {
 		al->level = 'g';
 		mg = &machine->kmaps;
+		load_map = true;
 	} else {
 		/*
 		 * 'u' means guest os user space.

@@ -654,8 +657,15 @@ try_again:
 			mg = &machine->kmaps;
 			goto try_again;
 		}
-	} else
+	} else {
+		/*
+		 * Kernel maps might be changed when loading symbols so loading
+		 * must be done prior to using kernel maps.
+		 */
+		if (load_map)
+			map__load(al->map, filter);
 		al->addr = al->map->map_ip(al->map, al->addr);
+	}
 }
 
 void thread__find_addr_location(struct thread *thread, struct machine *machine,

@@ -663,7 +673,7 @@ void thread__find_addr_location(struct thread *thread, struct machine *machine,
 				struct addr_location *al,
 				symbol_filter_t filter)
 {
-	thread__find_addr_map(thread, machine, cpumode, type, addr, al);
+	thread__find_addr_map(thread, machine, cpumode, type, addr, al, filter);
 	if (al->map != NULL)
 		al->sym = map__find_symbol(al->map, al->addr, filter);
 	else

@@ -699,7 +709,7 @@ int perf_event__preprocess_sample(const union perf_event *event,
 		machine__create_kernel_maps(machine);
 
 	thread__find_addr_map(thread, machine, cpumode, MAP__FUNCTION,
-			      event->ip.ip, al);
+			      event->ip.ip, al, filter);
 	dump_printf(" ...... dso: %s\n",
 		    al->map ? al->map->dso->long_name :
 			al->level == 'H' ? "[hypervisor]" : "<not found>");

index 0fe1f9c..f98d1d9 100644
@@ -41,7 +41,7 @@ static inline struct map *thread__find_map(struct thread *self,
 
 void thread__find_addr_map(struct thread *thread, struct machine *machine,
 			   u8 cpumode, enum map_type type, u64 addr,
-			   struct addr_location *al);
+			   struct addr_location *al, symbol_filter_t filter);
 
 void thread__find_addr_location(struct thread *thread, struct machine *machine,
 				u8 cpumode, enum map_type type, u64 addr,

index 958723b..5bbd494 100644
@@ -272,7 +272,7 @@ static struct map *find_map(unw_word_t ip, struct unwind_info *ui)
 	struct addr_location al;
 
 	thread__find_addr_map(ui->thread, ui->machine, PERF_RECORD_MISC_USER,
-			      MAP__FUNCTION, ip, &al);
+			      MAP__FUNCTION, ip, &al, NULL);
 	return al.map;
 }
 

@@ -349,7 +349,7 @@ static int access_dso_mem(struct unwind_info *ui, unw_word_t addr,
 	ssize_t size;
 
 	thread__find_addr_map(ui->thread, ui->machine, PERF_RECORD_MISC_USER,
-			      MAP__FUNCTION, addr, &al);
+			      MAP__FUNCTION, addr, &al, NULL);
 	if (!al.map) {
 		pr_debug("unwind: no map for %lx\n", (unsigned long)addr);
 		return -1;

index c4374f0..121583d 100644
@@ -78,6 +78,8 @@ int dso__binary_type_file(struct dso *dso, enum dso_binary_type type,
 			 symbol_conf.symfs, build_id_hex, build_id_hex + 2);
 		break;
 
+	case DSO_BINARY_TYPE__VMLINUX:
+	case DSO_BINARY_TYPE__GUEST_VMLINUX:
 	case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
 		snprintf(file, size, "%s%s",
 			 symbol_conf.symfs, dso->long_name);

@@ -95,9 +97,7 @@ int dso__binary_type_file(struct dso *dso, enum dso_binary_type type,
 
 	default:
 	case DSO_BINARY_TYPE__KALLSYMS:
-	case DSO_BINARY_TYPE__VMLINUX:
 	case DSO_BINARY_TYPE__GUEST_KALLSYMS:
-	case DSO_BINARY_TYPE__GUEST_VMLINUX:
 	case DSO_BINARY_TYPE__JAVA_JIT:
 	case DSO_BINARY_TYPE__NOT_FOUND:
 		ret = -1;

index d51aaf2..02aadaf 100644
@@ -3,6 +3,7 @@
 
 #include <linux/types.h>
 #include <linux/rbtree.h>
+#include <stdbool.h>
 #include "types.h"
 #include "map.h"
 

@@ -146,4 +147,11 @@ size_t dso__fprintf_buildid(struct dso *dso, FILE *fp);
 size_t dso__fprintf_symbols_by_name(struct dso *dso,
 				    enum map_type type, FILE *fp);
 size_t dso__fprintf(struct dso *dso, enum map_type type, FILE *fp);
+
+static inline bool dso__is_vmlinux(struct dso *dso)
+{
+	return dso->data_type == DSO_BINARY_TYPE__VMLINUX ||
+	       dso->data_type == DSO_BINARY_TYPE__GUEST_VMLINUX;
+}
+
 #endif /* __PERF_DSO */

index f9f9d63..dc35dcf 100644
@@ -628,10 +628,8 @@ int machine__load_vmlinux_path(struct machine *machine, enum map_type type,
 	struct map *map = machine->vmlinux_maps[type];
 	int ret = dso__load_vmlinux_path(map->dso, map, filter);
 
-	if (ret > 0) {
+	if (ret > 0)
 		dso__set_loaded(map->dso, type);
-		map__reloc_vmlinux(map);
-	}
 
 	return ret;
 }

index 8bcdf9e..5f662a3 100644
@@ -182,12 +182,6 @@ int map__load(struct map *map, symbol_filter_t filter)
 #endif
 		return -1;
 	}
-	/*
-	 * Only applies to the kernel, as its symtabs aren't relative like the
-	 * module ones.
-	 */
-	if (map->dso->kernel)
-		map__reloc_vmlinux(map);
 
 	return 0;
 }

@@ -513,35 +507,6 @@ int map_groups__clone(struct map_groups *mg,
 	return 0;
 }
 
-static u64 map__reloc_map_ip(struct map *map, u64 ip)
-{
-	return ip + (s64)map->pgoff;
-}
-
-static u64 map__reloc_unmap_ip(struct map *map, u64 ip)
-{
-	return ip - (s64)map->pgoff;
-}
-
-void map__reloc_vmlinux(struct map *map)
-{
-	struct kmap *kmap = map__kmap(map);
-	s64 reloc;
-
-	if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->unrelocated_addr)
-		return;
-
-	reloc = (kmap->ref_reloc_sym->unrelocated_addr -
-		 kmap->ref_reloc_sym->addr);
-
-	if (!reloc)
-		return;
-
-	map->map_ip   = map__reloc_map_ip;
-	map->unmap_ip = map__reloc_unmap_ip;
-	map->pgoff    = reloc;
-}
-
 void maps__insert(struct rb_root *maps, struct map *map)
 {
 	struct rb_node **p = &maps->rb_node;

150 lines not on this page · raw message

index ea62ecd..04300dd 100644
@@ -917,6 +917,10 @@ int dso__load_vmlinux(struct dso *dso, struct map *map,
 	symsrc__destroy(&ss);
 
 	if (err > 0) {
+		if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
+			dso->data_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
+		else
+			dso->data_type = DSO_BINARY_TYPE__VMLINUX;
 		dso__set_long_name(dso, (char *)vmlinux);
 		dso__set_loaded(dso, map->type);
 		pr_debug("Using %s for symbols\n", symfs_vmlinux);

@@ -989,7 +993,7 @@ static int dso__load_kernel_sym(struct dso *dso, struct map *map,
 			dso__set_long_name(dso,
 					   strdup(symbol_conf.vmlinux_name));
 			dso->lname_alloc = 1;
-			goto out_fixup;
+			return err;
 		}
 		return err;
 	}

@@ -997,7 +1001,7 @@ static int dso__load_kernel_sym(struct dso *dso, struct map *map,
 	if (vmlinux_path != NULL) {
 		err = dso__load_vmlinux_path(dso, map, filter);
 		if (err > 0)
-			goto out_fixup;
+			return err;
 	}
 
 	/* do not try local files if a symfs was given */

@@ -1058,7 +1062,6 @@ do_kallsyms:
 
 	if (err > 0) {
 		dso__set_long_name(dso, strdup("[kernel.kallsyms]"));
-out_fixup:
 		map__fixup_start(map);
 		map__fixup_end(map);
 	}

@@ -1089,7 +1092,7 @@ static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
 		if (symbol_conf.default_guest_vmlinux_name != NULL) {
 			err = dso__load_vmlinux(dso, map,
 				symbol_conf.default_guest_vmlinux_name, filter);
-			goto out_try_fixup;
+			return err;
 		}
 
 		kallsyms_filename = symbol_conf.default_guest_kallsyms;

@@ -1101,15 +1104,10 @@ static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
 	}
 
 	err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
-	if (err > 0)
-		pr_debug("Using %s for symbols\n", kallsyms_filename);
-
-out_try_fixup:
 	if (err > 0) {
-		if (kallsyms_filename != NULL) {
-			machine__mmap_name(machine, path, sizeof(path));
-			dso__set_long_name(dso, strdup(path));
-		}
+		pr_debug("Using %s for symbols\n", kallsyms_filename);
+		machine__mmap_name(machine, path, sizeof(path));
+		dso__set_long_name(dso, strdup(path));
 		map__fixup_start(map);
 		map__fixup_end(map);
 	}

index add1539..e2e1498 100644
@@ -25,6 +25,7 @@ int test__vmlinux_matches_kallsyms(void)
 	struct machine kallsyms, vmlinux;
 	enum map_type type = MAP__FUNCTION;
 	struct ref_reloc_sym ref_reloc_sym = { .name = "_stext", };
+	u64 mem_start, mem_end;
 
 	/*
 	 * Step 1:

@@ -123,10 +124,14 @@ int test__vmlinux_matches_kallsyms(void)
 		if (sym->start == sym->end)
 			continue;
 
-		first_pair = machine__find_kernel_symbol(&kallsyms, type, sym->start, NULL, NULL);
+		mem_start = vmlinux_map->unmap_ip(vmlinux_map, sym->start);
+		mem_end = vmlinux_map->unmap_ip(vmlinux_map, sym->end);
+
+		first_pair = machine__find_kernel_symbol(&kallsyms, type,
+							 mem_start, NULL, NULL);
 		pair = first_pair;
 
-		if (pair && pair->start == sym->start) {
+		if (pair && pair->start == mem_start) {
 next_pair:
 			if (strcmp(sym->name, pair->name) == 0) {
 				/*

@@ -138,10 +143,11 @@ next_pair:
 				 * off the real size. More than that and we
 				 * _really_ have a problem.
 				 */
-				s64 skew = sym->end - pair->end;
+				s64 skew = mem_end - pair->end;
 				if (llabs(skew) >= page_size)
 					pr_debug("%#" PRIx64 ": diff end addr for %s v: %#" PRIx64 " k: %#" PRIx64 "\n",
-						 sym->start, sym->name, sym->end, pair->end);
+						 mem_start, sym->name, mem_end,
+						 pair->end);
 
 				/*
 				 * Do not count this as a failure, because we

@@ -159,7 +165,7 @@ detour:
 				if (nnd) {
 					struct symbol *next = rb_entry(nnd, struct symbol, rb_node);
 
-					if (next->start == sym->start) {
+					if (next->start == mem_start) {
 						pair = next;
 						goto next_pair;
 					}

@@ -172,10 +178,11 @@ detour:
 				}
 
 				pr_debug("%#" PRIx64 ": diff name v: %s k: %s\n",
-					 sym->start, sym->name, pair->name);
+					 mem_start, sym->name, pair->name);
 			}
 		} else
-			pr_debug("%#" PRIx64 ": %s not on kallsyms\n", sym->start, sym->name);
+			pr_debug("%#" PRIx64 ": %s not on kallsyms\n",
+				 mem_start, sym->name);
 
 		err = -1;
 	}

@@ -208,16 +215,19 @@ detour:
 	for (nd = rb_first(&vmlinux.kmaps.maps[type]); nd; nd = rb_next(nd)) {
 		struct map *pos = rb_entry(nd, struct map, rb_node), *pair;
 
-		pair = map_groups__find(&kallsyms.kmaps, type, pos->start);
+		mem_start = vmlinux_map->unmap_ip(vmlinux_map, pos->start);
+		mem_end = vmlinux_map->unmap_ip(vmlinux_map, pos->end);
+
+		pair = map_groups__find(&kallsyms.kmaps, type, mem_start);
 		if (pair == NULL || pair->priv)
 			continue;
 
-		if (pair->start == pos->start) {
+		if (pair->start == mem_start) {
 			pair->priv = 1;
 			pr_info(" %" PRIx64 "-%" PRIx64 " %" PRIx64 " %s in kallsyms as",
 				pos->start, pos->end, pos->pgoff, pos->dso->name);
-			if (pos->pgoff != pair->pgoff || pos->end != pair->end)
-				pr_info(": \n*%" PRIx64 "-%" PRIx64 " %" PRIx64 "",
+			if (mem_end != pair->end)
+				pr_info(":\n*%" PRIx64 "-%" PRIx64 " %" PRIx64,
 					pair->start, pair->end, pair->pgoff);
 			pr_info(" %s\n", pair->dso->name);
 			pair->priv = 1;

index 02718e7..ea62ecd 100644
@@ -87,6 +87,7 @@ static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
 {
 	s64 a;
 	s64 b;
+	size_t na, nb;
 
 	/* Prefer a symbol with non zero length */
 	a = syma->end - syma->start;

@@ -120,11 +121,21 @@ static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
 	else if (a > b)
 		return SYMBOL_B;
 
-	/* If all else fails, choose the symbol with the longest name */
-	if (strlen(syma->name) >= strlen(symb->name))
+	/* Choose the symbol with the longest name */
+	na = strlen(syma->name);
+	nb = strlen(symb->name);
+	if (na > nb)
 		return SYMBOL_A;
-	else
+	else if (na < nb)
+		return SYMBOL_B;
+
+	/* Avoid "SyS" kernel syscall aliases */
+	if (na >= 3 && !strncmp(syma->name, "SyS", 3))
 		return SYMBOL_B;
+	if (na >= 10 && !strncmp(syma->name, "compat_SyS", 10))
+		return SYMBOL_B;
+
+	return SYMBOL_A;
 }
 
 void symbols__fixup_duplicate(struct rb_root *symbols)

index 121583d..1955804 100644
@@ -419,6 +419,7 @@ struct dso *dso__new(const char *name)
 		dso->symtab_type = DSO_BINARY_TYPE__NOT_FOUND;
 		dso->data_type   = DSO_BINARY_TYPE__NOT_FOUND;
 		dso->loaded = 0;
+		dso->rel = 0;
 		dso->sorted_by_name = 0;
 		dso->has_build_id = 0;
 		dso->kernel = DSO_TYPE_USER;

index 02aadaf..735a837 100644
@@ -85,6 +85,7 @@ struct dso {
 	u8		 lname_alloc:1;
 	u8		 sorted_by_name;
 	u8		 loaded;
+	u8		 rel;
 	u8		 build_id[BUILD_ID_SIZE];
 	const char	 *short_name;
 	char		 *long_name;

index 5f662a3..4d599fe 100644
@@ -248,14 +248,18 @@ size_t map__fprintf_dsoname(struct map *map, FILE *fp)
 
 /*
  * objdump wants/reports absolute IPs for ET_EXEC, and RIPs for ET_DYN.
- * map->dso->adjust_symbols==1 for ET_EXEC-like cases.
+ * map->dso->adjust_symbols==1 for ET_EXEC-like cases except ET_REL which is
+ * relative to section start.
  */
 u64 map__rip_2objdump(struct map *map, u64 rip)
 {
-	u64 addr = map->dso->adjust_symbols ?
-			map->unmap_ip(map, rip) :	/* RIP -> IP */
-			rip;
-	return addr;
+	if (!map->dso->adjust_symbols)
+		return rip;
+
+	if (map->dso->rel)
+		return rip - map->pgoff;
+
+	return map->unmap_ip(map, rip);
 }
 
 void map_groups__init(struct map_groups *mg)

index ed6f443..3eaa7b4 100644
@@ -599,11 +599,13 @@ int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name,
 	if (dso->kernel == DSO_TYPE_USER) {
 		GElf_Shdr shdr;
 		ss->adjust_symbols = (ehdr.e_type == ET_EXEC ||
+				ehdr.e_type == ET_REL ||
 				elf_section_by_name(elf, &ehdr, &shdr,
 						     ".gnu.prelink_undo",
 						     NULL) != NULL);
 	} else {
-		ss->adjust_symbols = ehdr.e_type == ET_EXEC;
+		ss->adjust_symbols = ehdr.e_type == ET_EXEC ||
+				     ehdr.e_type == ET_REL;
 	}
 
 	ss->name   = strdup(name);

@@ -676,6 +678,14 @@ int dso__load_sym(struct dso *dso, struct map *map,
 	bool remap_kernel = false, adjust_kernel_syms = false;
 
 	dso->symtab_type = syms_ss->type;
+	dso->rel = syms_ss->ehdr.e_type == ET_REL;
+
+	/*
+	 * Modules may already have symbols from kallsyms, but those symbols
+	 * have the wrong values for the dso maps, so remove them.
+	 */
+	if (kmodule && syms_ss->symtab)
+		symbols__delete(&dso->symbols[map->type]);
 
 	if (!syms_ss->symtab) {
 		syms_ss->symtab  = syms_ss->dynsym;

@@ -828,11 +838,24 @@ int dso__load_sym(struct dso *dso, struct map *map,
 					map_groups__insert(kmap->kmaps, map);
 				}
 
+				/*
+				 * The initial module mapping is based on
+				 * /proc/modules mapped to offset zero.
+				 * Overwrite it to map to the module dso.
+				 */
+				if (remap_kernel && kmodule) {
+					remap_kernel = false;
+					map->pgoff = shdr.sh_offset;
+				}
+
 				curr_map = map;
 				curr_dso = dso;
 				goto new_symbol;
 			}
 
+			if (!kmap)
+				goto new_symbol;
+
 			snprintf(dso_name, sizeof(dso_name),
 				 "%s%s", dso->short_name, section_name);
 

index 04300dd..b9056a8 100644
@@ -854,10 +854,15 @@ int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter)
 	if (!runtime_ss && syms_ss)
 		runtime_ss = syms_ss;
 
-	if (syms_ss)
-		ret = dso__load_sym(dso, map, syms_ss, runtime_ss, filter, 0);
-	else
+	if (syms_ss) {
+		int km;
+
+		km = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
+		     dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE;
+		ret = dso__load_sym(dso, map, syms_ss, runtime_ss, filter, km);
+	} else {
 		ret = -1;
+	}
 
 	if (ret > 0) {
 		int nr_plt;

index 1955804..e3c1ff8 100644
@@ -95,6 +95,11 @@ int dso__binary_type_file(struct dso *dso, enum dso_binary_type type,
 			 dso->long_name);
 		break;
 
+	case DSO_BINARY_TYPE__KCORE:
+	case DSO_BINARY_TYPE__GUEST_KCORE:
+		snprintf(file, size, "%s", dso->long_name);
+		break;
+
 	default:
 	case DSO_BINARY_TYPE__KALLSYMS:
 	case DSO_BINARY_TYPE__GUEST_KALLSYMS:

index 735a837..b793053 100644
@@ -21,6 +21,8 @@ enum dso_binary_type {
 	DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
 	DSO_BINARY_TYPE__GUEST_KMODULE,
 	DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
+	DSO_BINARY_TYPE__KCORE,
+	DSO_BINARY_TYPE__GUEST_KCORE,
 	DSO_BINARY_TYPE__NOT_FOUND,
 };
 

@@ -155,4 +157,10 @@ static inline bool dso__is_vmlinux(struct dso *dso)
 	       dso->data_type == DSO_BINARY_TYPE__GUEST_VMLINUX;
 }
 
+static inline bool dso__is_kcore(struct dso *dso)
+{
+	return dso->data_type == DSO_BINARY_TYPE__KCORE ||
+	       dso->data_type == DSO_BINARY_TYPE__GUEST_KCORE;
+}
+
 #endif /* __PERF_DSO */

index dc35dcf..ef3b49c 100644
@@ -856,6 +856,18 @@ static void machine__set_kernel_mmap_len(struct machine *machine,
 	}
 }
 
+static bool machine__uses_kcore(struct machine *machine)
+{
+	struct dso *dso;
+
+	list_for_each_entry(dso, &machine->kernel_dsos, node) {
+		if (dso__is_kcore(dso))
+			return true;
+	}
+
+	return false;
+}
+
 static int machine__process_kernel_mmap_event(struct machine *machine,
 					      union perf_event *event)
 {

@@ -864,6 +876,10 @@ static int machine__process_kernel_mmap_event(struct machine *machine,
 	enum dso_kernel_type kernel_type;
 	bool is_kernel_mmap;
 
+	/* If we have maps from kcore then we do not need or want any others */
+	if (machine__uses_kcore(machine))
+		return 0;
+
 	machine__mmap_name(machine, kmmap_prefix, sizeof(kmmap_prefix));
 	if (machine__is_host(machine))
 		kernel_type = DSO_TYPE_KERNEL;

index 4d599fe..9e8304c 100644
@@ -555,3 +555,21 @@ struct map *maps__find(struct rb_root *maps, u64 ip)
 
 	return NULL;
 }
+
+struct map *maps__first(struct rb_root *maps)
+{
+	struct rb_node *first = rb_first(maps);
+
+	if (first)
+		return rb_entry(first, struct map, rb_node);
+	return NULL;
+}
+
+struct map *maps__next(struct map *map)
+{
+	struct rb_node *next = rb_next(&map->rb_node);
+
+	if (next)
+		return rb_entry(next, struct map, rb_node);
+	return NULL;
+}

index a887f2c..2cc93cb 100644
@@ -112,6 +112,8 @@ size_t __map_groups__fprintf_maps(struct map_groups *mg,
 void maps__insert(struct rb_root *maps, struct map *map);
 void maps__remove(struct rb_root *maps, struct map *map);
 struct map *maps__find(struct rb_root *maps, u64 addr);
+struct map *maps__first(struct rb_root *maps);
+struct map *maps__next(struct map *map);
 void map_groups__init(struct map_groups *mg);
 void map_groups__exit(struct map_groups *mg);
 int map_groups__clone(struct map_groups *mg,

@@ -139,6 +141,17 @@ static inline struct map *map_groups__find(struct map_groups *mg,
 	return maps__find(&mg->maps[type], addr);
 }
 
+static inline struct map *map_groups__first(struct map_groups *mg,
+					    enum map_type type)
+{
+	return maps__first(&mg->maps[type]);
+}
+
+static inline struct map *map_groups__next(struct map *map)
+{
+	return maps__next(map);
+}
+
 struct symbol *map_groups__find_symbol(struct map_groups *mg,
 				       enum map_type type, u64 addr,
 				       struct map **mapp,

57 lines not on this page · raw message

index a7390cd..3a802c3 100644
@@ -301,6 +301,13 @@ int dso__load_sym(struct dso *dso, struct map *map __maybe_unused,
 	return 0;
 }
 
+int file__read_maps(int fd __maybe_unused, bool exe __maybe_unused,
+		    mapfn_t mapfn __maybe_unused, void *data __maybe_unused,
+		    bool *is_64_bit __maybe_unused)
+{
+	return -1;
+}
+
 void symbol__elf_init(void)
 {
 }

270 lines not on this page · raw message

index 5f720dc..fd5b70e 100644
@@ -215,6 +215,7 @@ struct symbol *dso__find_symbol(struct dso *dso, enum map_type type,
 				u64 addr);
 struct symbol *dso__find_symbol_by_name(struct dso *dso, enum map_type type,
 					const char *name);
+struct symbol *dso__first_symbol(struct dso *dso, enum map_type type);
 
 int filename__read_build_id(const char *filename, void *bf, size_t size);
 int sysfs__read_build_id(const char *filename, void *bf, size_t size);

@@ -247,4 +248,8 @@ void symbols__fixup_duplicate(struct rb_root *symbols);
 void symbols__fixup_end(struct rb_root *symbols);
 void __map_groups__fixup_end(struct map_groups *mg, enum map_type type);
 
+typedef int (*mapfn_t)(u64 start, u64 len, u64 pgoff, void *data);
+int file__read_maps(int fd, bool exe, mapfn_t mapfn, void *data,
+		    bool *is_64_bit);
+
 #endif /* __PERF_SYMBOL */

index fe7a27d..e9e1c03 100644
@@ -186,7 +186,7 @@ void parse_proc_kallsyms(struct pevent *pevent,
 	char *next = NULL;
 	char *addr_str;
 	char *mod;
-	char *fmt;
+	char *fmt = NULL;
 
 	line = strtok_r(file, "\n", &next);
 	while (line) {

index e2e1498..2bd13ed 100644
@@ -16,6 +16,8 @@ static int vmlinux_matches_kallsyms_filter(struct map *map __maybe_unused,
 	return 0;
 }
 
+#define UM(x) kallsyms_map->unmap_ip(kallsyms_map, (x))
+
 int test__vmlinux_matches_kallsyms(void)
 {
 	int err = -1;

@@ -74,7 +76,7 @@ int test__vmlinux_matches_kallsyms(void)
 		goto out;
 	}
 
-	ref_reloc_sym.addr = sym->start;
+	ref_reloc_sym.addr = UM(sym->start);
 
 	/*
 	 * Step 5:

@@ -131,7 +133,7 @@ int test__vmlinux_matches_kallsyms(void)
 							 mem_start, NULL, NULL);
 		pair = first_pair;
 
-		if (pair && pair->start == mem_start) {
+		if (pair && UM(pair->start) == mem_start) {
 next_pair:
 			if (strcmp(sym->name, pair->name) == 0) {
 				/*

@@ -143,11 +145,11 @@ next_pair:
 				 * off the real size. More than that and we
 				 * _really_ have a problem.
 				 */
-				s64 skew = mem_end - pair->end;
+				s64 skew = mem_end - UM(pair->end);
 				if (llabs(skew) >= page_size)
 					pr_debug("%#" PRIx64 ": diff end addr for %s v: %#" PRIx64 " k: %#" PRIx64 "\n",
 						 mem_start, sym->name, mem_end,
-						 pair->end);
+						 UM(pair->end));
 
 				/*
 				 * Do not count this as a failure, because we

@@ -165,7 +167,7 @@ detour:
 				if (nnd) {
 					struct symbol *next = rb_entry(nnd, struct symbol, rb_node);
 
-					if (next->start == mem_start) {
+					if (UM(next->start) == mem_start) {
 						pair = next;
 						goto next_pair;
 					}

index 0c7b052..8e0943b 100644
@@ -20,6 +20,11 @@
 #define BUFSZ	1024
 #define READLEN	128
 
+struct state {
+	u64 done[1024];
+	size_t done_cnt;
+};
+
 static unsigned int hex(char c)
 {
 	if (c >= '0' && c <= '9')

@@ -107,6 +112,9 @@ static int read_via_objdump(const char *filename, u64 addr, void *buf,
 
 	pr_debug("Objdump command is: %s\n", cmd);
 
+	/* Ignore objdump errors */
+	strcat(cmd, " 2>/dev/null");
+
 	f = popen(cmd, "r");
 	if (!f) {
 		pr_debug("popen failed\n");

@@ -126,7 +134,8 @@ static int read_via_objdump(const char *filename, u64 addr, void *buf,
 }
 
 static int read_object_code(u64 addr, size_t len, u8 cpumode,
-			    struct thread *thread, struct machine *machine)
+			    struct thread *thread, struct machine *machine,
+			    struct state *state)
 {
 	struct addr_location al;
 	unsigned char buf1[BUFSZ];

@@ -146,7 +155,8 @@ static int read_object_code(u64 addr, size_t len, u8 cpumode,
 
 	pr_debug("File is: %s\n", al.map->dso->long_name);
 
-	if (al.map->dso->symtab_type == DSO_BINARY_TYPE__KALLSYMS) {
+	if (al.map->dso->symtab_type == DSO_BINARY_TYPE__KALLSYMS &&
+	    !dso__is_kcore(al.map->dso)) {
 		pr_debug("Unexpected kernel address - skipping\n");
 		return 0;
 	}

@@ -175,6 +185,24 @@ static int read_object_code(u64 addr, size_t len, u8 cpumode,
 	if (map__load(al.map, NULL))
 		return -1;
 
+	/* objdump struggles with kcore - try each map only once */
+	if (dso__is_kcore(al.map->dso)) {
+		size_t d;
+
+		for (d = 0; d < state->done_cnt; d++) {
+			if (state->done[d] == al.map->start) {
+				pr_debug("kcore map tested already");
+				pr_debug(" - skipping\n");
+				return 0;
+			}
+		}
+		if (state->done_cnt >= ARRAY_SIZE(state->done)) {
+			pr_debug("Too many kcore maps - skipping\n");
+			return 0;
+		}
+		state->done[state->done_cnt++] = al.map->start;
+	}
+
 	/* Read the object code using objdump */
 	objdump_addr = map__rip_2objdump(al.map, al.addr);
 	ret = read_via_objdump(al.map->dso->long_name, objdump_addr, buf2, len);

@@ -186,10 +214,19 @@ static int read_object_code(u64 addr, size_t len, u8 cpumode,
 		if (cpumode == PERF_RECORD_MISC_KERNEL ||
 		    cpumode == PERF_RECORD_MISC_GUEST_KERNEL) {
 			len -= ret;
-			if (len)
+			if (len) {
 				pr_debug("Reducing len to %zu\n", len);
-			else
+			} else if (dso__is_kcore(al.map->dso)) {
+				/*
+				 * objdump cannot handle very large segments
+				 * that may be found in kcore.
+				 */
+				pr_debug("objdump failed for kcore");
+				pr_debug(" - skipping\n");
+				return 0;
+			} else {
 				return -1;
+			}
 		}
 	}
 	if (ret < 0) {

@@ -209,7 +246,7 @@ static int read_object_code(u64 addr, size_t len, u8 cpumode,
 
 static int process_sample_event(struct machine *machine,
 				struct perf_evlist *evlist,
-				union perf_event *event)
+				union perf_event *event, struct state *state)
 {
 	struct perf_sample sample;
 	struct thread *thread;

@@ -228,14 +265,15 @@ static int process_sample_event(struct machine *machine,
 
 	cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
 
-	return read_object_code(sample.ip, READLEN, cpumode, thread, machine);
+	return read_object_code(sample.ip, READLEN, cpumode, thread, machine,
+				state);
 }
 
 static int process_event(struct machine *machine, struct perf_evlist *evlist,
-			 union perf_event *event)
+			 union perf_event *event, struct state *state)
 {
 	if (event->header.type == PERF_RECORD_SAMPLE)
-		return process_sample_event(machine, evlist, event);
+		return process_sample_event(machine, evlist, event, state);
 
 	if (event->header.type < PERF_RECORD_MAX)
 		return machine__process_event(machine, event);

@@ -243,14 +281,15 @@ static int process_event(struct machine *machine, struct perf_evlist *evlist,
 	return 0;
 }
 
-static int process_events(struct machine *machine, struct perf_evlist *evlist)
+static int process_events(struct machine *machine, struct perf_evlist *evlist,
+			  struct state *state)
 {
 	union perf_event *event;
 	int i, ret;
 
 	for (i = 0; i < evlist->nr_mmaps; i++) {
 		while ((event = perf_evlist__mmap_read(evlist, i)) != NULL) {
-			ret = process_event(machine, evlist, event);
+			ret = process_event(machine, evlist, event, state);
 			if (ret < 0)
 				return ret;
 		}

@@ -331,10 +370,12 @@ static void do_something(void)
 enum {
 	TEST_CODE_READING_OK,
 	TEST_CODE_READING_NO_VMLINUX,
+	TEST_CODE_READING_NO_KCORE,
 	TEST_CODE_READING_NO_ACCESS,
+	TEST_CODE_READING_NO_KERNEL_OBJ,
 };
 
-static int do_test_code_reading(void)
+static int do_test_code_reading(bool try_kcore)
 {
 	struct machines machines;
 	struct machine *machine;

@@ -348,6 +389,9 @@ static int do_test_code_reading(void)
 			.uses_mmap   = true,
 		},
 	};
+	struct state state = {
+		.done_cnt = 0,
+	};
 	struct thread_map *threads = NULL;
 	struct cpu_map *cpus = NULL;
 	struct perf_evlist *evlist = NULL;

@@ -355,7 +399,7 @@ static int do_test_code_reading(void)
 	int err = -1, ret;
 	pid_t pid;
 	struct map *map;
-	bool have_vmlinux, excl_kernel = false;
+	bool have_vmlinux, have_kcore, excl_kernel = false;
 
 	pid = getpid();
 

@@ -368,6 +412,10 @@ static int do_test_code_reading(void)
 		goto out_err;
 	}
 
+	/* Force the use of kallsyms instead of vmlinux to try kcore */
+	if (try_kcore)
+		symbol_conf.kallsyms_name = "/proc/kallsyms";
+
 	/* Load kernel map */
 	map = machine->vmlinux_maps[MAP__FUNCTION];
 	ret = map__load(map, NULL);

@@ -375,9 +423,15 @@ static int do_test_code_reading(void)
 		pr_debug("map__load failed\n");
 		goto out_err;
 	}
-	have_vmlinux = map->dso->symtab_type == DSO_BINARY_TYPE__VMLINUX;
-	/* No point getting kernel events if there is no vmlinux */
-	if (!have_vmlinux)
+	have_vmlinux = dso__is_vmlinux(map->dso);
+	have_kcore = dso__is_kcore(map->dso);
+
+	/* 2nd time through we just try kcore */
+	if (try_kcore && !have_kcore)
+		return TEST_CODE_READING_NO_KCORE;
+
+	/* No point getting kernel events if there is no kernel object */
+	if (!have_vmlinux && !have_kcore)
 		excl_kernel = true;
 
 	threads = thread_map__new_by_tid(pid);

@@ -461,11 +515,13 @@ static int do_test_code_reading(void)
 
 	perf_evlist__disable(evlist);
 
-	ret = process_events(machine, evlist);
+	ret = process_events(machine, evlist, &state);
 	if (ret < 0)
 		goto out_err;
 
-	if (!have_vmlinux)
+	if (!have_vmlinux && !have_kcore && !try_kcore)
+		err = TEST_CODE_READING_NO_KERNEL_OBJ;
+	else if (!have_vmlinux && !try_kcore)
 		err = TEST_CODE_READING_NO_VMLINUX;
 	else if (excl_kernel)
 		err = TEST_CODE_READING_NO_ACCESS;

@@ -492,7 +548,9 @@ int test__code_reading(void)
 {
 	int ret;
 
-	ret = do_test_code_reading();
+	ret = do_test_code_reading(false);
+	if (!ret)
+		ret = do_test_code_reading(true);
 
 	switch (ret) {
 	case TEST_CODE_READING_OK:

@@ -500,9 +558,15 @@ int test__code_reading(void)
 	case TEST_CODE_READING_NO_VMLINUX:
 		fprintf(stderr, " (no vmlinux)");
 		return 0;
+	case TEST_CODE_READING_NO_KCORE:
+		fprintf(stderr, " (no kcore)");
+		return 0;
 	case TEST_CODE_READING_NO_ACCESS:
 		fprintf(stderr, " (no access)");
 		return 0;
+	case TEST_CODE_READING_NO_KERNEL_OBJ:
+		fprintf(stderr, " (no kernel obj)");
+		return 0;
 	default:
 		return -1;
 	};

index 9101f7c..440c3b3 100644
@@ -103,7 +103,8 @@ static int perf_top__parse_source(struct perf_top *top, struct hist_entry *he)
 	/*
 	 * We can't annotate with just /proc/kallsyms
 	 */
-	if (map->dso->symtab_type == DSO_BINARY_TYPE__KALLSYMS) {
+	if (map->dso->symtab_type == DSO_BINARY_TYPE__KALLSYMS &&
+	    !dso__is_kcore(map->dso)) {
 		pr_err("Can't annotate %s: No vmlinux file was found in the "
 		       "path\n", sym->name);
 		sleep(1);

index d102716..4ab2f11 100644
@@ -110,10 +110,10 @@ static int jump__parse(struct ins_operands *ops)
 {
 	const char *s = strchr(ops->raw, '+');
 
-	ops->target.addr = strtoll(ops->raw, NULL, 16);
+	ops->target.addr = strtoull(ops->raw, NULL, 16);
 
 	if (s++ != NULL)
-		ops->target.offset = strtoll(s, NULL, 16);
+		ops->target.offset = strtoull(s, NULL, 16);
 	else
 		ops->target.offset = UINT64_MAX;
 

@@ -821,6 +821,10 @@ static int symbol__parse_objdump_line(struct symbol *sym, struct map *map,
 	if (dl == NULL)
 		return -1;
 
+	if (dl->ops.target.offset == UINT64_MAX)
+		dl->ops.target.offset = dl->ops.target.addr -
+					map__rip_2objdump(map, sym->start);
+
 	disasm__add(&notes->src->source, dl);
 
 	return 0;

@@ -864,7 +868,8 @@ fallback:
 		free_filename = false;
 	}
 
-	if (dso->symtab_type == DSO_BINARY_TYPE__KALLSYMS) {
+	if (dso->symtab_type == DSO_BINARY_TYPE__KALLSYMS &&
+	    !dso__is_kcore(dso)) {
 		char bf[BUILD_ID_SIZE * 2 + 16] = " with build id ";
 		char *build_id_msg = NULL;
 

@@ -898,7 +903,7 @@ fallback:
 	snprintf(command, sizeof(command),
 		 "%s %s%s --start-address=0x%016" PRIx64
 		 " --stop-address=0x%016" PRIx64
-		 " -d %s %s -C %s|grep -v %s|expand",
+		 " -d %s %s -C %s 2>/dev/null|grep -v %s|expand",
 		 objdump_path ? objdump_path : "objdump",
 		 disassembler_style ? "-M " : "",
 		 disassembler_style ? disassembler_style : "",

index cc64d3f..0f88a77 100644
@@ -428,6 +428,14 @@ static void annotate_browser__init_asm_mode(struct annotate_browser *browser)
 	browser->b.nr_entries = browser->nr_asm_entries;
 }
 
+#define SYM_TITLE_MAX_SIZE (PATH_MAX + 64)
+
+static int sym_title(struct symbol *sym, struct map *map, char *title,
+		     size_t sz)
+{
+	return snprintf(title, sz, "%s  %s", sym->name, map->dso->long_name);
+}
+
 static bool annotate_browser__callq(struct annotate_browser *browser,
 				    struct perf_evsel *evsel,
 				    struct hist_browser_timer *hbt)

@@ -438,6 +446,7 @@ static bool annotate_browser__callq(struct annotate_browser *browser,
 	struct annotation *notes;
 	struct symbol *target;
 	u64 ip;
+	char title[SYM_TITLE_MAX_SIZE];
 
 	if (!ins__is_call(dl->ins))
 		return false;

@@ -461,7 +470,8 @@ static bool annotate_browser__callq(struct annotate_browser *browser,
 
 	pthread_mutex_unlock(&notes->lock);
 	symbol__tui_annotate(target, ms->map, evsel, hbt);
-	ui_browser__show_title(&browser->b, sym->name);
+	sym_title(sym, ms->map, title, sizeof(title));
+	ui_browser__show_title(&browser->b, title);
 	return true;
 }
 

@@ -653,8 +663,10 @@ static int annotate_browser__run(struct annotate_browser *browser,
 	const char *help = "Press 'h' for help on key bindings";
 	int delay_secs = hbt ? hbt->refresh : 0;
 	int key;
+	char title[SYM_TITLE_MAX_SIZE];
 
-	if (ui_browser__show(&browser->b, sym->name, help) < 0)
+	sym_title(sym, ms->map, title, sizeof(title));
+	if (ui_browser__show(&browser->b, title, help) < 0)
 		return -1;
 
 	annotate_browser__calc_percent(browser, evsel);

index 4ab2f11..646e38d 100644
@@ -830,6 +830,30 @@ static int symbol__parse_objdump_line(struct symbol *sym, struct map *map,
 	return 0;
 }
 
+static void delete_last_nop(struct symbol *sym)
+{
+	struct annotation *notes = symbol__annotation(sym);
+	struct list_head *list = &notes->src->source;
+	struct disasm_line *dl;
+
+	while (!list_empty(list)) {
+		dl = list_entry(list->prev, struct disasm_line, node);
+
+		if (dl->ins && dl->ins->ops) {
+			if (dl->ins->ops != &nop_ops)
+				return;
+		} else {
+			if (!strstr(dl->line, " nop ") &&
+			    !strstr(dl->line, " nopl ") &&
+			    !strstr(dl->line, " nopw "))
+				return;
+		}
+
+		list_del(&dl->node);
+		disasm_line__free(dl);
+	}
+}
+
 int symbol__annotate(struct symbol *sym, struct map *map, size_t privsize)
 {
 	struct dso *dso = map->dso;

@@ -923,6 +947,13 @@ fallback:
 		if (symbol__parse_objdump_line(sym, map, file, privsize) < 0)
 			break;
 
+	/*
+	 * kallsyms does not have symbol sizes so there may a nop at the end.
+	 * Remove it.
+	 */
+	if (dso__is_kcore(dso))
+		delete_last_nop(sym);
+
 	pclose(file);
 out_free_filename:
 	if (free_filename)

index 646e38d..bfc5a27 100644
@@ -825,6 +825,22 @@ static int symbol__parse_objdump_line(struct symbol *sym, struct map *map,
 		dl->ops.target.offset = dl->ops.target.addr -
 					map__rip_2objdump(map, sym->start);
 
+	/*
+	 * kcore has no symbols, so add the call target name if it is on the
+	 * same map.
+	 */
+	if (dl->ins && ins__is_call(dl->ins) && !dl->ops.target.name) {
+		struct symbol *s;
+		u64 ip = dl->ops.target.addr;
+
+		if (ip >= map->start && ip <= map->end) {
+			ip = map->map_ip(map, ip);
+			s = map__find_symbol(map, ip, NULL);
+			if (s && s->start == ip)
+				dl->ops.target.name = strdup(s->name);
+		}
+	}
+
 	disasm__add(&notes->src->source, dl);
 
 	return 0;