Commit 293d5b43 authored by Masami Hiramatsu's avatar Masami Hiramatsu Committed by Arnaldo Carvalho de Melo

perf probe: Support probing on offline cross-arch binary

Support probing on offline cross-architecture binary by adding getting
the target machine arch from ELF and choose correct register string for
the machine.

Here is an example:
  -----
  $ perf probe --vmlinux=./vmlinux-arm --definition 'do_sys_open $params'
  p:probe/do_sys_open do_sys_open+0 dfd=%r5:s32 filename=%r1:u32 flags=%r6:s32 mode=%r3:u16
  -----

Here, we can get probe/do_sys_open from above and append it to to the target
machine's tracing/kprobe_events file in the tracefs mountput, usually
/sys/kernel/debug/tracing/kprobe_events (or /sys/kernel/tracing/kprobe_events).
Signed-off-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/147214229717.23638.6440579792548044658.stgit@devbox
[ Add definition for EM_AARCH64 to fix the build on at least centos 6, debian 7 & ubuntu 12.04.5 ]
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 428aff82
#ifdef DEFINE_DWARF_REGSTR_TABLE
/* This is included in perf/util/dwarf-regs.c */
static const char * const arm_regstr_tbl[] = {
"%r0", "%r1", "%r2", "%r3", "%r4",
"%r5", "%r6", "%r7", "%r8", "%r9", "%r10",
"%fp", "%ip", "%sp", "%lr", "%pc",
};
#endif
#ifdef DEFINE_DWARF_REGSTR_TABLE
/* This is included in perf/util/dwarf-regs.c */
static const char * const aarch64_regstr_tbl[] = {
"%r0", "%r1", "%r2", "%r3", "%r4",
"%r5", "%r6", "%r7", "%r8", "%r9",
"%r10", "%r11", "%r12", "%r13", "%r14",
"%r15", "%r16", "%r17", "%r18", "%r19",
"%r20", "%r21", "%r22", "%r23", "%r24",
"%r25", "%r26", "%r27", "%r28", "%r29",
"%lr", "%sp",
};
#endif
#ifdef DEFINE_DWARF_REGSTR_TABLE
/* This is included in perf/util/dwarf-regs.c */
/*
* Reference:
* http://refspecs.linuxfoundation.org/ELF/ppc64/PPC-elf64abi-1.9.html
* http://refspecs.linux-foundation.org/elf/elfspec_ppc.pdf
*/
#define REG_DWARFNUM_NAME(reg, idx) [idx] = "%" #reg
static const char * const powerpc_regstr_tbl[] = {
"%gpr0", "%gpr1", "%gpr2", "%gpr3", "%gpr4",
"%gpr5", "%gpr6", "%gpr7", "%gpr8", "%gpr9",
"%gpr10", "%gpr11", "%gpr12", "%gpr13", "%gpr14",
"%gpr15", "%gpr16", "%gpr17", "%gpr18", "%gpr19",
"%gpr20", "%gpr21", "%gpr22", "%gpr23", "%gpr24",
"%gpr25", "%gpr26", "%gpr27", "%gpr28", "%gpr29",
"%gpr30", "%gpr31",
REG_DWARFNUM_NAME(msr, 66),
REG_DWARFNUM_NAME(ctr, 109),
REG_DWARFNUM_NAME(link, 108),
REG_DWARFNUM_NAME(xer, 101),
REG_DWARFNUM_NAME(dar, 119),
REG_DWARFNUM_NAME(dsisr, 118),
};
#endif
#ifdef DEFINE_DWARF_REGSTR_TABLE
/* This is included in perf/util/dwarf-regs.c */
static const char * const s390_regstr_tbl[] = {
"%r0", "%r1", "%r2", "%r3", "%r4", "%r5", "%r6", "%r7",
"%r8", "%r9", "%r10", "%r11", "%r12", "%r13", "%r14", "%r15",
};
#endif
#ifdef DEFINE_DWARF_REGSTR_TABLE
/* This is included in perf/util/dwarf-regs.c */
const char * const sh_regstr_tbl[] = {
"r0",
"r1",
"r2",
"r3",
"r4",
"r5",
"r6",
"r7",
"r8",
"r9",
"r10",
"r11",
"r12",
"r13",
"r14",
"r15",
"pc",
"pr",
};
#endif
#ifdef DEFINE_DWARF_REGSTR_TABLE
/* This is included in perf/util/dwarf-regs.c */
static const char * const sparc_regstr_tbl[] = {
"%g0", "%g1", "%g2", "%g3", "%g4", "%g5", "%g6", "%g7",
"%o0", "%o1", "%o2", "%o3", "%o4", "%o5", "%sp", "%o7",
"%l0", "%l1", "%l2", "%l3", "%l4", "%l5", "%l6", "%l7",
"%i0", "%i1", "%i2", "%i3", "%i4", "%i5", "%fp", "%i7",
"%f0", "%f1", "%f2", "%f3", "%f4", "%f5", "%f6", "%f7",
"%f8", "%f9", "%f10", "%f11", "%f12", "%f13", "%f14", "%f15",
"%f16", "%f17", "%f18", "%f19", "%f20", "%f21", "%f22", "%f23",
"%f24", "%f25", "%f26", "%f27", "%f28", "%f29", "%f30", "%f31",
"%f32", "%f33", "%f34", "%f35", "%f36", "%f37", "%f38", "%f39",
"%f40", "%f41", "%f42", "%f43", "%f44", "%f45", "%f46", "%f47",
"%f48", "%f49", "%f50", "%f51", "%f52", "%f53", "%f54", "%f55",
"%f56", "%f57", "%f58", "%f59", "%f60", "%f61", "%f62", "%f63",
};
#endif
#ifdef DEFINE_DWARF_REGSTR_TABLE
/* This is included in perf/util/dwarf-regs.c */
static const char * const x86_32_regstr_tbl[] = {
"%ax", "%cx", "%dx", "%bx", "$stack",/* Stack address instead of %sp */
"%bp", "%si", "%di",
};
static const char * const x86_64_regstr_tbl[] = {
"%ax", "dx", "%cx", "%bx", "%si", "%di",
"%bp", "%sp", "%r8", "%r9", "%r10", "%r11",
"%r12", "%r13", "%r14", "%r15",
};
#endif
#ifdef DEFINE_DWARF_REGSTR_TABLE
/* This is included in perf/util/dwarf-regs.c */
static const char * const xtensa_regstr_tbl[] = {
"a0", "a1", "a2", "a3", "a4", "a5", "a6", "a7",
"a8", "a9", "a10", "a11", "a12", "a13", "a14", "a15",
};
#endif
...@@ -98,6 +98,7 @@ endif ...@@ -98,6 +98,7 @@ endif
libperf-$(CONFIG_DWARF) += probe-finder.o libperf-$(CONFIG_DWARF) += probe-finder.o
libperf-$(CONFIG_DWARF) += dwarf-aux.o libperf-$(CONFIG_DWARF) += dwarf-aux.o
libperf-$(CONFIG_DWARF) += dwarf-regs.o
libperf-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o libperf-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o
libperf-$(CONFIG_LOCAL_LIBUNWIND) += unwind-libunwind-local.o libperf-$(CONFIG_LOCAL_LIBUNWIND) += unwind-libunwind-local.o
......
/*
* dwarf-regs.c : Mapping of DWARF debug register numbers into register names.
*
* Written by: Masami Hiramatsu <mhiramat@kernel.org>
*/
#include <util.h>
#include <debug.h>
#include <dwarf-regs.h>
#include <elf.h>
#ifndef EM_AARCH64
#define EM_AARCH64 183 /* ARM 64 bit */
#endif
/* Define const char * {arch}_register_tbl[] */
#define DEFINE_DWARF_REGSTR_TABLE
#include "../arch/x86/include/dwarf-regs-table.h"
#include "../arch/arm/include/dwarf-regs-table.h"
#include "../arch/arm64/include/dwarf-regs-table.h"
#include "../arch/sh/include/dwarf-regs-table.h"
#include "../arch/powerpc/include/dwarf-regs-table.h"
#include "../arch/s390/include/dwarf-regs-table.h"
#include "../arch/sparc/include/dwarf-regs-table.h"
#include "../arch/xtensa/include/dwarf-regs-table.h"
#define __get_dwarf_regstr(tbl, n) (((n) < ARRAY_SIZE(tbl)) ? (tbl)[(n)] : NULL)
/* Return architecture dependent register string (for kprobe-tracer) */
const char *get_dwarf_regstr(unsigned int n, unsigned int machine)
{
switch (machine) {
case EM_NONE: /* Generic arch - use host arch */
return get_arch_regstr(n);
case EM_386:
return __get_dwarf_regstr(x86_32_regstr_tbl, n);
case EM_X86_64:
return __get_dwarf_regstr(x86_64_regstr_tbl, n);
case EM_ARM:
return __get_dwarf_regstr(arm_regstr_tbl, n);
case EM_AARCH64:
return __get_dwarf_regstr(aarch64_regstr_tbl, n);
case EM_SH:
return __get_dwarf_regstr(sh_regstr_tbl, n);
case EM_S390:
return __get_dwarf_regstr(s390_regstr_tbl, n);
case EM_PPC:
case EM_PPC64:
return __get_dwarf_regstr(powerpc_regstr_tbl, n);
case EM_SPARC:
case EM_SPARCV9:
return __get_dwarf_regstr(sparc_regstr_tbl, n);
case EM_XTENSA:
return __get_dwarf_regstr(xtensa_regstr_tbl, n);
default:
pr_err("ELF MACHINE %x is not supported.\n", machine);
}
return NULL;
}
...@@ -3,6 +3,12 @@ ...@@ -3,6 +3,12 @@
#ifdef HAVE_DWARF_SUPPORT #ifdef HAVE_DWARF_SUPPORT
const char *get_arch_regstr(unsigned int n); const char *get_arch_regstr(unsigned int n);
/*
* get_dwarf_regstr - Returns ftrace register string from DWARF regnum
* n: DWARF register number
* machine: ELF machine signature (EM_*)
*/
const char *get_dwarf_regstr(unsigned int n, unsigned int machine);
#endif #endif
#ifdef HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET #ifdef HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET
......
...@@ -171,6 +171,7 @@ static struct probe_trace_arg_ref *alloc_trace_arg_ref(long offs) ...@@ -171,6 +171,7 @@ static struct probe_trace_arg_ref *alloc_trace_arg_ref(long offs)
*/ */
static int convert_variable_location(Dwarf_Die *vr_die, Dwarf_Addr addr, static int convert_variable_location(Dwarf_Die *vr_die, Dwarf_Addr addr,
Dwarf_Op *fb_ops, Dwarf_Die *sp_die, Dwarf_Op *fb_ops, Dwarf_Die *sp_die,
unsigned int machine,
struct probe_trace_arg *tvar) struct probe_trace_arg *tvar)
{ {
Dwarf_Attribute attr; Dwarf_Attribute attr;
...@@ -266,7 +267,7 @@ static int convert_variable_location(Dwarf_Die *vr_die, Dwarf_Addr addr, ...@@ -266,7 +267,7 @@ static int convert_variable_location(Dwarf_Die *vr_die, Dwarf_Addr addr,
if (!tvar) if (!tvar)
return ret2; return ret2;
regs = get_arch_regstr(regn); regs = get_dwarf_regstr(regn, machine);
if (!regs) { if (!regs) {
/* This should be a bug in DWARF or this tool */ /* This should be a bug in DWARF or this tool */
pr_warning("Mapping for the register number %u " pr_warning("Mapping for the register number %u "
...@@ -543,7 +544,7 @@ static int convert_variable(Dwarf_Die *vr_die, struct probe_finder *pf) ...@@ -543,7 +544,7 @@ static int convert_variable(Dwarf_Die *vr_die, struct probe_finder *pf)
dwarf_diename(vr_die)); dwarf_diename(vr_die));
ret = convert_variable_location(vr_die, pf->addr, pf->fb_ops, ret = convert_variable_location(vr_die, pf->addr, pf->fb_ops,
&pf->sp_die, pf->tvar); &pf->sp_die, pf->machine, pf->tvar);
if (ret == -ENOENT || ret == -EINVAL) { if (ret == -ENOENT || ret == -EINVAL) {
pr_err("Failed to find the location of the '%s' variable at this address.\n" pr_err("Failed to find the location of the '%s' variable at this address.\n"
" Perhaps it has been optimized out.\n" " Perhaps it has been optimized out.\n"
...@@ -1106,11 +1107,8 @@ static int debuginfo__find_probes(struct debuginfo *dbg, ...@@ -1106,11 +1107,8 @@ static int debuginfo__find_probes(struct debuginfo *dbg,
struct probe_finder *pf) struct probe_finder *pf)
{ {
int ret = 0; int ret = 0;
#if _ELFUTILS_PREREQ(0, 142)
Elf *elf; Elf *elf;
GElf_Ehdr ehdr; GElf_Ehdr ehdr;
GElf_Shdr shdr;
if (pf->cfi_eh || pf->cfi_dbg) if (pf->cfi_eh || pf->cfi_dbg)
return debuginfo__find_probe_location(dbg, pf); return debuginfo__find_probe_location(dbg, pf);
...@@ -1123,11 +1121,18 @@ static int debuginfo__find_probes(struct debuginfo *dbg, ...@@ -1123,11 +1121,18 @@ static int debuginfo__find_probes(struct debuginfo *dbg,
if (gelf_getehdr(elf, &ehdr) == NULL) if (gelf_getehdr(elf, &ehdr) == NULL)
return -EINVAL; return -EINVAL;
pf->machine = ehdr.e_machine;
#if _ELFUTILS_PREREQ(0, 142)
do {
GElf_Shdr shdr;
if (elf_section_by_name(elf, &ehdr, &shdr, ".eh_frame", NULL) && if (elf_section_by_name(elf, &ehdr, &shdr, ".eh_frame", NULL) &&
shdr.sh_type == SHT_PROGBITS) shdr.sh_type == SHT_PROGBITS)
pf->cfi_eh = dwarf_getcfi_elf(elf); pf->cfi_eh = dwarf_getcfi_elf(elf);
pf->cfi_dbg = dwarf_getcfi(dbg->dbg); pf->cfi_dbg = dwarf_getcfi(dbg->dbg);
} while (0);
#endif #endif
ret = debuginfo__find_probe_location(dbg, pf); ret = debuginfo__find_probe_location(dbg, pf);
...@@ -1155,7 +1160,7 @@ static int copy_variables_cb(Dwarf_Die *die_mem, void *data) ...@@ -1155,7 +1160,7 @@ static int copy_variables_cb(Dwarf_Die *die_mem, void *data)
(tag == DW_TAG_variable && vf->vars)) { (tag == DW_TAG_variable && vf->vars)) {
if (convert_variable_location(die_mem, vf->pf->addr, if (convert_variable_location(die_mem, vf->pf->addr,
vf->pf->fb_ops, &pf->sp_die, vf->pf->fb_ops, &pf->sp_die,
NULL) == 0) { pf->machine, NULL) == 0) {
vf->args[vf->nargs].var = (char *)dwarf_diename(die_mem); vf->args[vf->nargs].var = (char *)dwarf_diename(die_mem);
if (vf->args[vf->nargs].var == NULL) { if (vf->args[vf->nargs].var == NULL) {
vf->ret = -ENOMEM; vf->ret = -ENOMEM;
...@@ -1318,7 +1323,7 @@ static int collect_variables_cb(Dwarf_Die *die_mem, void *data) ...@@ -1318,7 +1323,7 @@ static int collect_variables_cb(Dwarf_Die *die_mem, void *data)
tag == DW_TAG_variable) { tag == DW_TAG_variable) {
ret = convert_variable_location(die_mem, af->pf.addr, ret = convert_variable_location(die_mem, af->pf.addr,
af->pf.fb_ops, &af->pf.sp_die, af->pf.fb_ops, &af->pf.sp_die,
NULL); af->pf.machine, NULL);
if (ret == 0 || ret == -ERANGE) { if (ret == 0 || ret == -ERANGE) {
int ret2; int ret2;
bool externs = !af->child; bool externs = !af->child;
......
...@@ -80,6 +80,7 @@ struct probe_finder { ...@@ -80,6 +80,7 @@ struct probe_finder {
Dwarf_CFI *cfi_dbg; Dwarf_CFI *cfi_dbg;
#endif #endif
Dwarf_Op *fb_ops; /* Frame base attribute */ Dwarf_Op *fb_ops; /* Frame base attribute */
unsigned int machine; /* Target machine arch */
struct perf_probe_arg *pvar; /* Current target variable */ struct perf_probe_arg *pvar; /* Current target variable */
struct probe_trace_arg *tvar; /* Current result variable */ struct probe_trace_arg *tvar; /* Current result variable */
}; };
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment