diff options
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/perf/Documentation/perf-probe.txt | 3 | ||||
| -rw-r--r-- | tools/perf/util/probe-event.c | 11 | ||||
| -rw-r--r-- | tools/perf/util/probe-event.h | 2 | ||||
| -rw-r--r-- | tools/perf/util/probe-file.c | 7 | ||||
| -rw-r--r-- | tools/perf/util/probe-file.h | 1 | ||||
| -rw-r--r-- | tools/perf/util/probe-finder.c | 19 | ||||
| -rwxr-xr-x | tools/testing/selftests/ftrace/ftracetest | 38 | ||||
| -rw-r--r-- | tools/testing/selftests/ftrace/test.d/functions | 4 | ||||
| -rw-r--r-- | tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_user.tc | 32 |
9 files changed, 101 insertions, 16 deletions
diff --git a/tools/perf/Documentation/perf-probe.txt b/tools/perf/Documentation/perf-probe.txt index b6866a05edd2..ed3ecfa422e1 100644 --- a/tools/perf/Documentation/perf-probe.txt +++ b/tools/perf/Documentation/perf-probe.txt @@ -194,12 +194,13 @@ PROBE ARGUMENT -------------- Each probe argument follows below syntax. - [NAME=]LOCALVAR|$retval|%REG|@SYMBOL[:TYPE] + [NAME=]LOCALVAR|$retval|%REG|@SYMBOL[:TYPE][@user] 'NAME' specifies the name of this argument (optional). You can use the name of local variable, local data structure member (e.g. var->field, var.field2), local array with fixed index (e.g. array[1], var->array[0], var->pointer[2]), or kprobe-tracer argument format (e.g. $retval, %ax, etc). Note that the name of this argument will be set as the last member name if you specify a local data structure member (e.g. field2 for 'var->field1.field2'.) '$vars' and '$params' special arguments are also available for NAME, '$vars' is expanded to the local variables (including function parameters) which can access at given probe point. '$params' is expanded to only the function parameters. 'TYPE' casts the type of this argument (optional). If omitted, perf probe automatically set the type based on debuginfo (*). Currently, basic types (u8/u16/u32/u64/s8/s16/s32/s64), hexadecimal integers (x/x8/x16/x32/x64), signedness casting (u/s), "string" and bitfield are supported. (see TYPES for detail) On x86 systems %REG is always the short form of the register: for example %AX. %RAX or %EAX is not valid. +"@user" is a special attribute which means the LOCALVAR will be treated as a user-space memory. This is only valid for kprobe event. TYPES ----- diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index 0c3b55d0617d..cd1eb73cfe83 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -1562,6 +1562,17 @@ static int parse_perf_probe_arg(char *str, struct perf_probe_arg *arg) str = tmp + 1; } + tmp = strchr(str, '@'); + if (tmp && tmp != str && strcmp(tmp + 1, "user")) { /* user attr */ + if (!user_access_is_supported()) { + semantic_error("ftrace does not support user access\n"); + return -EINVAL; + } + *tmp = '\0'; + arg->user_access = true; + pr_debug("user_access "); + } + tmp = strchr(str, ':'); if (tmp) { /* Type setting */ *tmp = '\0'; diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h index 05c8d571a901..96a319cd2378 100644 --- a/tools/perf/util/probe-event.h +++ b/tools/perf/util/probe-event.h @@ -37,6 +37,7 @@ struct probe_trace_point { struct probe_trace_arg_ref { struct probe_trace_arg_ref *next; /* Next reference */ long offset; /* Offset value */ + bool user_access; /* User-memory access */ }; /* kprobe-tracer and uprobe-tracer tracing argument */ @@ -82,6 +83,7 @@ struct perf_probe_arg { char *var; /* Variable name */ char *type; /* Type name */ struct perf_probe_arg_field *field; /* Structure fields */ + bool user_access; /* User-memory access */ }; /* Perf probe probing event (point + arg) */ diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c index c2998f90b23c..5b4d49382932 100644 --- a/tools/perf/util/probe-file.c +++ b/tools/perf/util/probe-file.c @@ -1005,6 +1005,7 @@ enum ftrace_readme { FTRACE_README_PROBE_TYPE_X = 0, FTRACE_README_KRETPROBE_OFFSET, FTRACE_README_UPROBE_REF_CTR, + FTRACE_README_USER_ACCESS, FTRACE_README_END, }; @@ -1017,6 +1018,7 @@ static struct { DEFINE_TYPE(FTRACE_README_PROBE_TYPE_X, "*type: * x8/16/32/64,*"), DEFINE_TYPE(FTRACE_README_KRETPROBE_OFFSET, "*place (kretprobe): *"), DEFINE_TYPE(FTRACE_README_UPROBE_REF_CTR, "*ref_ctr_offset*"), + DEFINE_TYPE(FTRACE_README_USER_ACCESS, "*[u]<offset>*"), }; static bool scan_ftrace_readme(enum ftrace_readme type) @@ -1077,3 +1079,8 @@ bool uprobe_ref_ctr_is_supported(void) { return scan_ftrace_readme(FTRACE_README_UPROBE_REF_CTR); } + +bool user_access_is_supported(void) +{ + return scan_ftrace_readme(FTRACE_README_USER_ACCESS); +} diff --git a/tools/perf/util/probe-file.h b/tools/perf/util/probe-file.h index 2a249182f2a6..986c1c94f64f 100644 --- a/tools/perf/util/probe-file.h +++ b/tools/perf/util/probe-file.h @@ -70,6 +70,7 @@ int probe_cache__show_all_caches(struct strfilter *filter); bool probe_type_is_available(enum probe_type type); bool kretprobe_offset_is_supported(void); bool uprobe_ref_ctr_is_supported(void); +bool user_access_is_supported(void); #else /* ! HAVE_LIBELF_SUPPORT */ static inline struct probe_cache *probe_cache__new(const char *tgt __maybe_unused, struct nsinfo *nsi __maybe_unused) { diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c index 7d8c99734928..025fc4491993 100644 --- a/tools/perf/util/probe-finder.c +++ b/tools/perf/util/probe-finder.c @@ -280,7 +280,7 @@ static_var: static int convert_variable_type(Dwarf_Die *vr_die, struct probe_trace_arg *tvar, - const char *cast) + const char *cast, bool user_access) { struct probe_trace_arg_ref **ref_ptr = &tvar->ref; Dwarf_Die type; @@ -320,7 +320,8 @@ static int convert_variable_type(Dwarf_Die *vr_die, pr_debug("%s type is %s.\n", dwarf_diename(vr_die), dwarf_diename(&type)); - if (cast && strcmp(cast, "string") == 0) { /* String type */ + if (cast && (!strcmp(cast, "string") || !strcmp(cast, "ustring"))) { + /* String type */ ret = dwarf_tag(&type); if (ret != DW_TAG_pointer_type && ret != DW_TAG_array_type) { @@ -343,6 +344,7 @@ static int convert_variable_type(Dwarf_Die *vr_die, pr_warning("Out of memory error\n"); return -ENOMEM; } + (*ref_ptr)->user_access = user_access; } if (!die_compare_name(&type, "char") && !die_compare_name(&type, "unsigned char")) { @@ -397,7 +399,7 @@ formatted: static int convert_variable_fields(Dwarf_Die *vr_die, const char *varname, struct perf_probe_arg_field *field, struct probe_trace_arg_ref **ref_ptr, - Dwarf_Die *die_mem) + Dwarf_Die *die_mem, bool user_access) { struct probe_trace_arg_ref *ref = *ref_ptr; Dwarf_Die type; @@ -434,6 +436,7 @@ static int convert_variable_fields(Dwarf_Die *vr_die, const char *varname, *ref_ptr = ref; } ref->offset += dwarf_bytesize(&type) * field->index; + ref->user_access = user_access; goto next; } else if (tag == DW_TAG_pointer_type) { /* Check the pointer and dereference */ @@ -505,17 +508,18 @@ static int convert_variable_fields(Dwarf_Die *vr_die, const char *varname, } } ref->offset += (long)offs; + ref->user_access = user_access; /* If this member is unnamed, we need to reuse this field */ if (!dwarf_diename(die_mem)) return convert_variable_fields(die_mem, varname, field, - &ref, die_mem); + &ref, die_mem, user_access); next: /* Converting next field */ if (field->next) return convert_variable_fields(die_mem, field->name, - field->next, &ref, die_mem); + field->next, &ref, die_mem, user_access); else return 0; } @@ -541,11 +545,12 @@ static int convert_variable(Dwarf_Die *vr_die, struct probe_finder *pf) else if (ret == 0 && pf->pvar->field) { ret = convert_variable_fields(vr_die, pf->pvar->var, pf->pvar->field, &pf->tvar->ref, - &die_mem); + &die_mem, pf->pvar->user_access); vr_die = &die_mem; } if (ret == 0) - ret = convert_variable_type(vr_die, pf->tvar, pf->pvar->type); + ret = convert_variable_type(vr_die, pf->tvar, pf->pvar->type, + pf->pvar->user_access); /* *expr will be cached in libdw. Don't free it. */ return ret; } diff --git a/tools/testing/selftests/ftrace/ftracetest b/tools/testing/selftests/ftrace/ftracetest index 6d5e9e87c4b7..063ecb290a5a 100755 --- a/tools/testing/selftests/ftrace/ftracetest +++ b/tools/testing/selftests/ftrace/ftracetest @@ -23,9 +23,15 @@ echo " If <dir> is -, all logs output in console only" exit $1 } +# default error +err_ret=1 + +# kselftest skip code is 4 +err_skip=4 + errexit() { # message echo "Error: $1" 1>&2 - exit 1 + exit $err_ret } # Ensuring user privilege @@ -116,11 +122,31 @@ parse_opts() { # opts } # Parameters -DEBUGFS_DIR=`grep debugfs /proc/mounts | cut -f2 -d' ' | head -1` -if [ -z "$DEBUGFS_DIR" ]; then - TRACING_DIR=`grep tracefs /proc/mounts | cut -f2 -d' ' | head -1` -else - TRACING_DIR=$DEBUGFS_DIR/tracing +TRACING_DIR=`grep tracefs /proc/mounts | cut -f2 -d' ' | head -1` +if [ -z "$TRACING_DIR" ]; then + DEBUGFS_DIR=`grep debugfs /proc/mounts | cut -f2 -d' ' | head -1` + if [ -z "$DEBUGFS_DIR" ]; then + # If tracefs exists, then so does /sys/kernel/tracing + if [ -d "/sys/kernel/tracing" ]; then + mount -t tracefs nodev /sys/kernel/tracing || + errexit "Failed to mount /sys/kernel/tracing" + TRACING_DIR="/sys/kernel/tracing" + # If debugfs exists, then so does /sys/kernel/debug + elif [ -d "/sys/kernel/debug" ]; then + mount -t debugfs nodev /sys/kernel/debug || + errexit "Failed to mount /sys/kernel/debug" + TRACING_DIR="/sys/kernel/debug/tracing" + else + err_ret=$err_skip + errexit "debugfs and tracefs are not configured in this kernel" + fi + else + TRACING_DIR="$DEBUGFS_DIR/tracing" + fi +fi +if [ ! -d "$TRACING_DIR" ]; then + err_ret=$err_skip + errexit "ftrace is not configured in this kernel" fi TOP_DIR=`absdir $0` diff --git a/tools/testing/selftests/ftrace/test.d/functions b/tools/testing/selftests/ftrace/test.d/functions index 779ec11f61bd..1d96c5f7e402 100644 --- a/tools/testing/selftests/ftrace/test.d/functions +++ b/tools/testing/selftests/ftrace/test.d/functions @@ -91,8 +91,8 @@ initialize_ftrace() { # Reset ftrace to initial-state reset_events_filter reset_ftrace_filter disable_events - echo > set_event_pid # event tracer is always on - echo > set_ftrace_pid + [ -f set_event_pid ] && echo > set_event_pid + [ -f set_ftrace_pid ] && echo > set_ftrace_pid [ -f set_ftrace_filter ] && echo | tee set_ftrace_* [ -f set_graph_function ] && echo | tee set_graph_* [ -f stack_trace_filter ] && echo > stack_trace_filter diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_user.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_user.tc new file mode 100644 index 000000000000..0f60087583d8 --- /dev/null +++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_args_user.tc @@ -0,0 +1,32 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 +# description: Kprobe event user-memory access + +[ -f kprobe_events ] || exit_unsupported # this is configurable + +grep -q '\$arg<N>' README || exit_unresolved # depends on arch +grep -A10 "fetcharg:" README | grep -q 'ustring' || exit_unsupported +grep -A10 "fetcharg:" README | grep -q '\[u\]<offset>' || exit_unsupported + +:;: "user-memory access syntax and ustring working on user memory";: +echo 'p:myevent do_sys_open path=+0($arg2):ustring path2=+u0($arg2):string' \ + > kprobe_events + +grep myevent kprobe_events | \ + grep -q 'path=+0($arg2):ustring path2=+u0($arg2):string' +echo 1 > events/kprobes/myevent/enable +echo > /dev/null +echo 0 > events/kprobes/myevent/enable + +grep myevent trace | grep -q 'path="/dev/null" path2="/dev/null"' + +:;: "user-memory access syntax and ustring not working with kernel memory";: +echo 'p:myevent vfs_symlink path=+0($arg3):ustring path2=+u0($arg3):string' \ + > kprobe_events +echo 1 > events/kprobes/myevent/enable +ln -s foo $TMPDIR/bar +echo 0 > events/kprobes/myevent/enable + +grep myevent trace | grep -q 'path=(fault) path2=(fault)' + +exit 0 |
