(2012/04/25 14:54), Prashanth Nageshappa wrote: > This patch is to augment Srikar's perf support for uprobes patch > (https://lkml.org/lkml/2012/4/11/191) with the following features: > > a. Instruction verification for user space tracing > b. Function boundary validation support to uprobes as its kernel > counterpart (Commit-ID: 1c1bc922). > > This will help in ensuring uprobe is placed at right location inside > the intended function. > > To verify instructions in perf before adding a uprobe, we need to use > arch/x86/lib/insn.c. Since perf Makefile enables -Wswitch-default flag > it causes build warnings/failures. Masami's patch > https://lkml.org/lkml/2012/4/12/598 addresses those warnings and it is > a pre-req for this patch. > > v3 addresses Arnaldo's review comments. > > v2 addresses Masami's review comments: Rebuild insn.c and inat.c while > building perf and a few other minor ones. This looks good for me :) > > Signed-off-by: Prashanth Nageshappa <prashanth@xxxxxxxxxxxxxxxxxx> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx> Thanks! > --- > > tools/perf/Makefile | 1 > tools/perf/arch/x86/Makefile | 20 ++++++++ > tools/perf/arch/x86/util/probe-event.c | 81 ++++++++++++++++++++++++++++++++ > tools/perf/util/include/linux/string.h | 1 > tools/perf/util/probe-event.c | 23 +++++++++ > tools/perf/util/probe-event.h | 2 + > tools/perf/util/symbol.c | 2 + > tools/perf/util/symbol.h | 1 > 8 files changed, 130 insertions(+), 1 deletions(-) > create mode 100644 tools/perf/arch/x86/util/probe-event.c > > diff --git a/tools/perf/Makefile b/tools/perf/Makefile > index 820371f..94879b9 100644 > --- a/tools/perf/Makefile > +++ b/tools/perf/Makefile > @@ -61,6 +61,7 @@ ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/i386/ -e s/sun4u/sparc64/ \ > > CC = $(CROSS_COMPILE)gcc > AR = $(CROSS_COMPILE)ar > +AWK = awk > > # Additional ARCH settings for x86 > ifeq ($(ARCH),i386) > diff --git a/tools/perf/arch/x86/Makefile b/tools/perf/arch/x86/Makefile > index 744e629..1a7215b 100644 > --- a/tools/perf/arch/x86/Makefile > +++ b/tools/perf/arch/x86/Makefile > @@ -1,5 +1,25 @@ > +inat_tables_script = ../../arch/$(ARCH)/tools/gen-insn-attr-x86.awk > +inat_tables_maps = ../../arch/$(ARCH)/lib/x86-opcode-map.txt > +cmd_inat_tables = $(AWK) -f $(inat_tables_script) $(inat_tables_maps) > $@ || rm -f $@ > + > +BASIC_CFLAGS += -I. -I../../arch/$(ARCH)/include > + > ifndef NO_DWARF > PERF_HAVE_DWARF_REGS := 1 > LIB_OBJS += $(OUTPUT)arch/$(ARCH)/util/dwarf-regs.o > endif > LIB_OBJS += $(OUTPUT)arch/$(ARCH)/util/header.o > +LIB_OBJS += $(OUTPUT)arch/$(ARCH)/util/probe-event.o > +LIB_OBJS += $(OUTPUT)arch/$(ARCH)/inat.o > +LIB_OBJS += $(OUTPUT)arch/$(ARCH)/insn.o > + > +$(OUTPUT)arch/$(ARCH)/inat.o:../../arch/$(ARCH)/lib/inat-tables.c > + > +../../arch/$(ARCH)/lib/inat-tables.c: $(inat_tables_script) $(inat_tables_maps) > + $(cmd_inat_tables) > + > +$(OUTPUT)arch/$(ARCH)/inat.o:../../arch/$(ARCH)/lib/inat.c $(OUTPUT)PERF-CFLAGS > + $(QUIET_CC)$(CC) -o $@ -c $(ALL_CFLAGS) $< > + > +$(OUTPUT)arch/$(ARCH)/insn.o:../../arch/$(ARCH)/lib/insn.c $(OUTPUT)PERF-CFLAGS > + $(QUIET_CC)$(CC) -o $@ -c $(ALL_CFLAGS) $< > diff --git a/tools/perf/arch/x86/util/probe-event.c b/tools/perf/arch/x86/util/probe-event.c > new file mode 100644 > index 0000000..f1ebf90 > --- /dev/null > +++ b/tools/perf/arch/x86/util/probe-event.c > @@ -0,0 +1,81 @@ > +/* > + * probe-event.c : x86 specific perf-probe definition > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; either version 2 of the License, or > + * (at your option) any later version. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program; if not, write to the Free Software > + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. > + * > + * Copyright (C) IBM Corporation, 2011-2012 > + * Authors: > + * Prashanth Nageshappa > + */ > + > +#include <util/types.h> > +#include <util/probe-event.h> > +#include <sys/types.h> > +#include <sys/stat.h> > +#include <unistd.h> > +#include <fcntl.h> > +#include <string.h> > +#include <errno.h> > +#include <asm/insn.h> > +#include <elf.h> > + > +/* > + * Check if a given offset from start of a function is valid or not > + */ > +bool can_probe(char *name, u64 vaddr, unsigned long offset, > + u8 class) > +{ > + u64 eaddr, saddr; > + unsigned long fileoffset, readbytes; > + int fd = 0; > + bool ret = false; > + char *buf = NULL; > + struct insn insn; > + > + fd = open(name, O_RDONLY); > + if (fd == -1) { > + pr_warning("Failed to open %s: %s\n", name, strerror(errno)); > + return ret; > + } > + buf = malloc(offset + MAX_INSN_SIZE); > + if (buf == NULL) { > + pr_warning("Failed to allocate memory"); > + goto out_close; > + } > + fileoffset = lseek(fd, vaddr, SEEK_SET); > + if (fileoffset != vaddr) { > + pr_warning("Failed to lseek %s: %s\n", name, strerror(errno)); > + goto out_free; > + } > + saddr = (u64)buf; > + eaddr = (u64)buf + offset; > + readbytes = read(fd, buf, offset + MAX_INSN_SIZE); > + if (readbytes != offset + MAX_INSN_SIZE) { > + pr_warning("Failed to read %s: %s\n", name, strerror(errno)); > + goto out_free; > + } > + while (saddr < eaddr) { > + insn_init(&insn, (void *)saddr, class == ELFCLASS64); > + insn_get_length(&insn); > + saddr += insn.length; > + } > + ret = (saddr == eaddr); > + > +out_free: > + free(buf); > +out_close: > + close(fd); > + return ret; > +} > diff --git a/tools/perf/util/include/linux/string.h b/tools/perf/util/include/linux/string.h > index 3b2f590..9d5eb21 100644 > --- a/tools/perf/util/include/linux/string.h > +++ b/tools/perf/util/include/linux/string.h > @@ -1 +1,2 @@ > #include <string.h> > +#include <perf.h> > diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c > index b7dec82..57f9eae 100644 > --- a/tools/perf/util/probe-event.c > +++ b/tools/perf/util/probe-event.c > @@ -2254,6 +2254,17 @@ int show_available_funcs(const char *target, struct strfilter *_filter, > } > > /* > + * Check if a given offset from start of a function is valid or not > + */ > +bool __attribute__((weak)) can_probe(char *name __used, > + u64 vaddr __used, > + unsigned long offset __used, > + u8 class __used) > +{ > + return true; > +} > + > +/* > * uprobe_events only accepts address: > * Convert function and any offset to address > */ > @@ -2307,7 +2318,17 @@ static int convert_name_to_addr(struct perf_probe_event *pev, const char *exec) > > if (map->start > sym->start) > vaddr = map->start; > - vaddr += sym->start + pp->offset + map->pgoff; > + > + vaddr += sym->start + map->pgoff; > + if (pp->offset) { > + if ((vaddr + pp->offset > sym->end) || > + !can_probe(name, vaddr, pp->offset, > + map->dso->class)) { > + pr_err("Failed to insert probe, ensure offset is within function and on insn boundary.\n"); > + return -EINVAL; > + } > + } > + vaddr += pp->offset; > pp->offset = 0; > > if (!pev->event) { > diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h > index f9f3de8..9ec2f8c 100644 > --- a/tools/perf/util/probe-event.h > +++ b/tools/perf/util/probe-event.h > @@ -137,4 +137,6 @@ extern int show_available_funcs(const char *module, struct strfilter *filter, > /* Maximum index number of event-name postfix */ > #define MAX_EVENT_INDEX 1024 > > +extern bool can_probe(char *name, u64 vaddr, unsigned long offset, > + u8 class); > #endif /*_PROBE_EVENT_H */ > diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c > index caaf75a..be58b06 100644 > --- a/tools/perf/util/symbol.c > +++ b/tools/perf/util/symbol.c > @@ -1184,6 +1184,7 @@ static int dso__load_sym(struct dso *dso, struct map *map, const char *name, > goto out_close; > } > > + dso->class = gelf_getclass(elf); > if (gelf_getehdr(elf, &ehdr) == NULL) { > pr_debug("%s: cannot get elf header.\n", __func__); > goto out_elf_end; > @@ -1326,6 +1327,7 @@ static int dso__load_sym(struct dso *dso, struct map *map, const char *name, > curr_dso->kernel = dso->kernel; > curr_dso->long_name = dso->long_name; > curr_dso->long_name_len = dso->long_name_len; > + curr_dso->class = dso->class; > curr_map = map__new2(start, curr_dso, > map->type); > if (curr_map == NULL) { > diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h > index 9e7742c..1d0cc28 100644 > --- a/tools/perf/util/symbol.h > +++ b/tools/perf/util/symbol.h > @@ -174,6 +174,7 @@ struct dso { > char *long_name; > u16 long_name_len; > u16 short_name_len; > + u8 class; > char name[0]; > }; > > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ -- Masami HIRAMATSU Software Platform Research Dept. Linux Technology Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: masami.hiramatsu.pt@xxxxxxxxxxx -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>