Commit 9518e10c authored by Ian Rogers's avatar Ian Rogers Committed by Arnaldo Carvalho de Melo
Browse files

perf dso: Move read_symbol() from llvm/capstone to dso 



Move the read_symbol function to dso.h, make the return type const and
add a mutable out_buf out parameter.

In future changes this will allow a code pointer to be returned without
necessary allocating memory.

Signed-off-by: default avatarIan Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexandre Ghiti <alexghiti@rivosinc.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.ibm.com>
Cc: Bill Wendling <morbo@google.com>
Cc: Charlie Jenkins <charlie@rivosinc.com>
Cc: Collin Funk <collin.funk1@gmail.com>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Dr. David Alan Gilbert <linux@treblig.org>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: Haibo Xu <haibo1.xu@intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Justin Stitt <justinstitt@google.com>
Cc: Li Huafei <lihuafei1@huawei.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <nick.desaulniers+lkml@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 0e52f3f9

tools/perf/util/capstone.c

+11 −55
Original line number Diff line number Diff line
@@ -215,55 +215,6 @@ static int find_file_offset(u64 start, u64 len, u64 pgoff, void *arg) 
}

#endif



#ifdef HAVE_LIBCAPSTONE_SUPPORT

static u8 *

read_symbol(const char *filename, struct map *map, struct symbol *sym,

	    u64 *len, bool *is_64bit)

{

	struct dso *dso = map__dso(map);

	struct nscookie nsc;

	u64 start = map__rip_2objdump(map, sym->start);

	u64 end = map__rip_2objdump(map, sym->end);

	int fd, count;

	u8 *buf = NULL;

	struct find_file_offset_data data = {

		.ip = start,

	};



	*is_64bit = false;



	nsinfo__mountns_enter(dso__nsinfo(dso), &nsc);

	fd = open(filename, O_RDONLY);

	nsinfo__mountns_exit(&nsc);

	if (fd < 0)

		return NULL;



	if (file__read_maps(fd, /*exe=*/true, find_file_offset, &data,

			    is_64bit) == 0)

		goto err;



	*len = end - start;

	buf = malloc(*len);

	if (buf == NULL)

		goto err;



	count = pread(fd, buf, *len, data.offset);

	close(fd);

	fd = -1;



	if ((u64)count != *len)

		goto err;



	return buf;



err:

	if (fd >= 0)

		close(fd);

	free(buf);

	return NULL;

}

#endif



int symbol__disassemble_capstone(const char *filename __maybe_unused,

				 struct symbol *sym __maybe_unused,

				 struct annotate_args *args __maybe_unused)
@@ -271,13 +222,17 @@ int symbol__disassemble_capstone(const char *filename __maybe_unused, 
#ifdef HAVE_LIBCAPSTONE_SUPPORT

	struct annotation *notes = symbol__annotation(sym);

	struct map *map = args->ms.map;

	struct dso *dso = map__dso(map);

	u64 start = map__rip_2objdump(map, sym->start);

	u64 len;

	u64 offset;

	int i, count, free_count;

	bool is_64bit = false;

	bool needs_cs_close = false;

	u8 *buf = NULL;

	/* Malloc-ed buffer containing instructions read from disk. */

	u8 *code_buf = NULL;

	/* Pointer to code to be disassembled. */

	const u8 *buf;

	u64 buf_len;

	csh handle;

	cs_insn *insn = NULL;

	char disasm_buf[512];
@@ -287,7 +242,8 @@ int symbol__disassemble_capstone(const char *filename __maybe_unused, 
	if (args->options->objdump_path)

		return -1;



	buf = read_symbol(filename, map, sym, &len, &is_64bit);

	buf = dso__read_symbol(dso, filename, map, sym,

			       &code_buf, &buf_len, &is_64bit);

	if (buf == NULL)

		return -1;
@@ -316,7 +272,7 @@ int symbol__disassemble_capstone(const char *filename __maybe_unused, 


	needs_cs_close = true;



	free_count = count = cs_disasm(handle, buf, len, start, len, &insn);

	free_count = count = cs_disasm(handle, buf, buf_len, start, buf_len, &insn);

	for (i = 0, offset = 0; i < count; i++) {

		int printed;
@@ -340,7 +296,7 @@ int symbol__disassemble_capstone(const char *filename __maybe_unused, 
	}



	/* It failed in the middle: probably due to unknown instructions */

	if (offset != len) {

	if (offset != buf_len) {

		struct list_head *list = &notes->src->source;



		/* Discard all lines and fallback to objdump */
@@ -359,7 +315,7 @@ int symbol__disassemble_capstone(const char *filename __maybe_unused, 
		if (free_count > 0)

			cs_free(insn, free_count);

	}

	free(buf);

	free(code_buf);

	return count < 0 ? count : 0;



err:

tools/perf/util/dso.c

+67 −0
Original line number Diff line number Diff line
@@ -1798,3 +1798,70 @@ bool is_perf_pid_map_name(const char *dso_name) 


	return perf_pid_map_tid(dso_name, &tid);

}



struct find_file_offset_data {

	u64 ip;

	u64 offset;

};



/* This will be called for each PHDR in an ELF binary */

static int find_file_offset(u64 start, u64 len, u64 pgoff, void *arg)

{

	struct find_file_offset_data *data = arg;



	if (start <= data->ip && data->ip < start + len) {

		data->offset = pgoff + data->ip - start;

		return 1;

	}

	return 0;

}



const u8 *dso__read_symbol(struct dso *dso, const char *symfs_filename,

			   const struct map *map, const struct symbol *sym,

			   u8 **out_buf, u64 *out_buf_len, bool *is_64bit)

{

	struct nscookie nsc;

	u64 start = map__rip_2objdump(map, sym->start);

	u64 end = map__rip_2objdump(map, sym->end);

	int fd, count;

	u8 *buf = NULL;

	size_t len;

	struct find_file_offset_data data = {

		.ip = start,

	};



	*out_buf = NULL;

	*out_buf_len = 0;

	*is_64bit = false;



	nsinfo__mountns_enter(dso__nsinfo(dso), &nsc);

	fd = open(symfs_filename, O_RDONLY);

	nsinfo__mountns_exit(&nsc);

	if (fd < 0)

		return NULL;



	if (file__read_maps(fd, /*exe=*/true, find_file_offset, &data, is_64bit) == 0)

		goto err;



	len = end - start;

	buf = malloc(len);

	if (buf == NULL)

		goto err;



	count = pread(fd, buf, len, data.offset);

	close(fd);

	fd = -1;



	if ((u64)count != len)

		goto err;



	*out_buf = buf;

	*out_buf_len = len;

	return buf;



err:

	if (fd >= 0)

		close(fd);

	free(buf);

	return NULL;

}

tools/perf/util/dso.h

+4 −0
Original line number Diff line number Diff line
@@ -924,4 +924,8 @@ static inline struct debuginfo *dso__debuginfo(struct dso *dso) 
	return debuginfo__new(dso__long_name(dso));

}



const u8 *dso__read_symbol(struct dso *dso, const char *symfs_filename,

			   const struct map *map, const struct symbol *sym,

			   u8 **out_buf, u64 *out_buf_len, bool *is_64bit);



#endif /* __PERF_DSO */

tools/perf/util/llvm.c

+15 −73
Original line number Diff line number Diff line
@@ -87,71 +87,6 @@ static void init_llvm(void) 
	}

}



struct find_file_offset_data {

	u64 ip;

	u64 offset;

};



/* This will be called for each PHDR in an ELF binary */

static int find_file_offset(u64 start, u64 len, u64 pgoff, void *arg)

{

	struct find_file_offset_data *data = arg;



	if (start <= data->ip && data->ip < start + len) {

		data->offset = pgoff + data->ip - start;

		return 1;

	}

	return 0;

}



static u8 *

read_symbol(const char *filename, struct map *map, struct symbol *sym,

	    u64 *len, bool *is_64bit)

{

	struct dso *dso = map__dso(map);

	struct nscookie nsc;

	u64 start = map__rip_2objdump(map, sym->start);

	u64 end = map__rip_2objdump(map, sym->end);

	int fd, count;

	u8 *buf = NULL;

	struct find_file_offset_data data = {

		.ip = start,

	};



	*is_64bit = false;



	nsinfo__mountns_enter(dso__nsinfo(dso), &nsc);

	fd = open(filename, O_RDONLY);

	nsinfo__mountns_exit(&nsc);

	if (fd < 0)

		return NULL;



	if (file__read_maps(fd, /*exe=*/true, find_file_offset, &data,

			    is_64bit) == 0)

		goto err;



	*len = end - start;

	buf = malloc(*len);

	if (buf == NULL)

		goto err;



	count = pread(fd, buf, *len, data.offset);

	close(fd);

	fd = -1;



	if ((u64)count != *len)

		goto err;



	return buf;



err:

	if (fd >= 0)

		close(fd);

	free(buf);

	return NULL;

}

#endif



/*

 * Whenever LLVM wants to resolve an address into a symbol, it calls this

 * callback. We don't ever actually _return_ anything (in particular, because
@@ -160,7 +95,6 @@ read_symbol(const char *filename, struct map *map, struct symbol *sym, 
 * should add some textual annotation for after the instruction. The caller

 * will use this information to add the actual annotation.

 */

#ifdef HAVE_LIBLLVM_SUPPORT

struct symbol_lookup_storage {

	u64 branch_addr;

	u64 pcrel_load_addr;
@@ -191,8 +125,11 @@ int symbol__disassemble_llvm(const char *filename, struct symbol *sym, 
	struct map *map = args->ms.map;

	struct dso *dso = map__dso(map);

	u64 start = map__rip_2objdump(map, sym->start);

	u8 *buf;

	u64 len;

	/* Malloc-ed buffer containing instructions read from disk. */

	u8 *code_buf = NULL;

	/* Pointer to code to be disassembled. */

	const u8 *buf;

	u64 buf_len;

	u64 pc;

	bool is_64bit;

	char disasm_buf[2048];
@@ -207,7 +144,8 @@ int symbol__disassemble_llvm(const char *filename, struct symbol *sym, 
	if (args->options->objdump_path)

		return -1;



	buf = read_symbol(filename, map, sym, &len, &is_64bit);

	buf = dso__read_symbol(dso, filename, map, sym,

			       &code_buf, &buf_len, &is_64bit);

	if (buf == NULL)

		return -1;
@@ -259,14 +197,18 @@ int symbol__disassemble_llvm(const char *filename, struct symbol *sym, 
	annotation_line__add(&dl->al, &notes->src->source);



	pc = start;

	for (u64 offset = 0; offset < len; ) {

	for (u64 offset = 0; offset < buf_len; ) {

		unsigned int ins_len;



		storage.branch_addr = 0;

		storage.pcrel_load_addr = 0;



		ins_len = LLVMDisasmInstruction(disasm, buf + offset,

						len - offset, pc,

		/*

		 * LLVM's API has the code be disassembled as non-const, cast

		 * here as we may be disassembling from mapped read-only memory.

		 */

		ins_len = LLVMDisasmInstruction(disasm, (u8 *)(buf + offset),

						buf_len - offset, pc,

						disasm_buf, sizeof(disasm_buf));

		if (ins_len == 0)

			goto err;
@@ -324,7 +266,7 @@ int symbol__disassemble_llvm(const char *filename, struct symbol *sym, 


err:

	LLVMDisasmDispose(disasm);

	free(buf);

	free(code_buf);

	free(line_storage);

	return ret;

#else // HAVE_LIBLLVM_SUPPORT