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-rw-r--r--kernel/trace/blktrace.c8
-rw-r--r--kernel/trace/bpf_trace.c66
-rw-r--r--kernel/trace/ftrace.c37
-rw-r--r--kernel/trace/trace.c44
-rw-r--r--kernel/trace/trace.h5
-rw-r--r--kernel/trace/trace_entries.h6
-rw-r--r--kernel/trace/trace_functions.c12
-rw-r--r--kernel/trace/trace_hwlat.c14
-rw-r--r--kernel/trace/trace_kprobe.c19
-rw-r--r--kernel/trace/trace_output.c9
-rw-r--r--kernel/trace/trace_stack.c6
11 files changed, 143 insertions, 83 deletions
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index bd8ae8d5ae9c..bc364f86100a 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -867,7 +867,7 @@ static void blk_add_trace_split(void *ignore,
__blk_add_trace(bt, bio->bi_iter.bi_sector,
bio->bi_iter.bi_size, bio_op(bio), bio->bi_opf,
- BLK_TA_SPLIT, bio->bi_error, sizeof(rpdu),
+ BLK_TA_SPLIT, bio->bi_status, sizeof(rpdu),
&rpdu);
}
}
@@ -900,7 +900,7 @@ static void blk_add_trace_bio_remap(void *ignore,
r.sector_from = cpu_to_be64(from);
__blk_add_trace(bt, bio->bi_iter.bi_sector, bio->bi_iter.bi_size,
- bio_op(bio), bio->bi_opf, BLK_TA_REMAP, bio->bi_error,
+ bio_op(bio), bio->bi_opf, BLK_TA_REMAP, bio->bi_status,
sizeof(r), &r);
}
@@ -1662,14 +1662,14 @@ static ssize_t sysfs_blk_trace_attr_store(struct device *dev,
goto out;
if (attr == &dev_attr_act_mask) {
- if (sscanf(buf, "%llx", &value) != 1) {
+ if (kstrtoull(buf, 0, &value)) {
/* Assume it is a list of trace category names */
ret = blk_trace_str2mask(buf);
if (ret < 0)
goto out;
value = ret;
}
- } else if (sscanf(buf, "%llu", &value) != 1)
+ } else if (kstrtoull(buf, 0, &value))
goto out;
ret = -ENXIO;
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 460a031c77e5..37385193a608 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -122,8 +122,8 @@ static const struct bpf_func_proto *bpf_get_probe_write_proto(void)
}
/*
- * limited trace_printk()
- * only %d %u %x %ld %lu %lx %lld %llu %llx %p %s conversion specifiers allowed
+ * Only limited trace_printk() conversion specifiers allowed:
+ * %d %i %u %x %ld %li %lu %lx %lld %lli %llu %llx %p %s
*/
BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1,
u64, arg2, u64, arg3)
@@ -198,7 +198,8 @@ BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1,
i++;
}
- if (fmt[i] != 'd' && fmt[i] != 'u' && fmt[i] != 'x')
+ if (fmt[i] != 'i' && fmt[i] != 'd' &&
+ fmt[i] != 'u' && fmt[i] != 'x')
return -EINVAL;
fmt_cnt++;
}
@@ -234,7 +235,8 @@ BPF_CALL_2(bpf_perf_event_read, struct bpf_map *, map, u64, flags)
unsigned int cpu = smp_processor_id();
u64 index = flags & BPF_F_INDEX_MASK;
struct bpf_event_entry *ee;
- struct perf_event *event;
+ u64 value = 0;
+ int err;
if (unlikely(flags & ~(BPF_F_INDEX_MASK)))
return -EINVAL;
@@ -247,21 +249,14 @@ BPF_CALL_2(bpf_perf_event_read, struct bpf_map *, map, u64, flags)
if (!ee)
return -ENOENT;
- event = ee->event;
- if (unlikely(event->attr.type != PERF_TYPE_HARDWARE &&
- event->attr.type != PERF_TYPE_RAW))
- return -EINVAL;
-
- /* make sure event is local and doesn't have pmu::count */
- if (unlikely(event->oncpu != cpu || event->pmu->count))
- return -EINVAL;
-
+ err = perf_event_read_local(ee->event, &value);
/*
- * we don't know if the function is run successfully by the
- * return value. It can be judged in other places, such as
- * eBPF programs.
+ * this api is ugly since we miss [-22..-2] range of valid
+ * counter values, but that's uapi
*/
- return perf_event_read_local(event);
+ if (err)
+ return err;
+ return value;
}
static const struct bpf_func_proto bpf_perf_event_read_proto = {
@@ -272,14 +267,16 @@ static const struct bpf_func_proto bpf_perf_event_read_proto = {
.arg2_type = ARG_ANYTHING,
};
+static DEFINE_PER_CPU(struct perf_sample_data, bpf_sd);
+
static __always_inline u64
__bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map,
u64 flags, struct perf_raw_record *raw)
{
struct bpf_array *array = container_of(map, struct bpf_array, map);
+ struct perf_sample_data *sd = this_cpu_ptr(&bpf_sd);
unsigned int cpu = smp_processor_id();
u64 index = flags & BPF_F_INDEX_MASK;
- struct perf_sample_data sample_data;
struct bpf_event_entry *ee;
struct perf_event *event;
@@ -300,9 +297,9 @@ __bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map,
if (unlikely(event->oncpu != cpu))
return -EOPNOTSUPP;
- perf_sample_data_init(&sample_data, 0, 0);
- sample_data.raw = raw;
- perf_event_output(event, &sample_data, regs);
+ perf_sample_data_init(sd, 0, 0);
+ sd->raw = raw;
+ perf_event_output(event, sd, regs);
return 0;
}
@@ -483,7 +480,7 @@ static const struct bpf_func_proto *kprobe_prog_func_proto(enum bpf_func_id func
/* bpf+kprobe programs can access fields of 'struct pt_regs' */
static bool kprobe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
- enum bpf_reg_type *reg_type)
+ struct bpf_insn_access_aux *info)
{
if (off < 0 || off >= sizeof(struct pt_regs))
return false;
@@ -566,7 +563,7 @@ static const struct bpf_func_proto *tp_prog_func_proto(enum bpf_func_id func_id)
}
static bool tp_prog_is_valid_access(int off, int size, enum bpf_access_type type,
- enum bpf_reg_type *reg_type)
+ struct bpf_insn_access_aux *info)
{
if (off < sizeof(void *) || off >= PERF_MAX_TRACE_SIZE)
return false;
@@ -585,40 +582,47 @@ const struct bpf_verifier_ops tracepoint_prog_ops = {
};
static bool pe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
- enum bpf_reg_type *reg_type)
+ struct bpf_insn_access_aux *info)
{
+ const int size_sp = FIELD_SIZEOF(struct bpf_perf_event_data,
+ sample_period);
+
if (off < 0 || off >= sizeof(struct bpf_perf_event_data))
return false;
if (type != BPF_READ)
return false;
if (off % size != 0)
return false;
- if (off == offsetof(struct bpf_perf_event_data, sample_period)) {
- if (size != sizeof(u64))
+
+ switch (off) {
+ case bpf_ctx_range(struct bpf_perf_event_data, sample_period):
+ bpf_ctx_record_field_size(info, size_sp);
+ if (!bpf_ctx_narrow_access_ok(off, size, size_sp))
return false;
- } else {
+ break;
+ default:
if (size != sizeof(long))
return false;
}
+
return true;
}
static u32 pe_prog_convert_ctx_access(enum bpf_access_type type,
const struct bpf_insn *si,
struct bpf_insn *insn_buf,
- struct bpf_prog *prog)
+ struct bpf_prog *prog, u32 *target_size)
{
struct bpf_insn *insn = insn_buf;
switch (si->off) {
case offsetof(struct bpf_perf_event_data, sample_period):
- BUILD_BUG_ON(FIELD_SIZEOF(struct perf_sample_data, period) != sizeof(u64));
-
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
data), si->dst_reg, si->src_reg,
offsetof(struct bpf_perf_event_data_kern, data));
*insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
- offsetof(struct perf_sample_data, period));
+ bpf_target_off(struct perf_sample_data, period, 8,
+ target_size));
break;
default:
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 00077a57b746..b308be30dfb9 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -3631,22 +3631,20 @@ ftrace_match_record(struct dyn_ftrace *rec, struct ftrace_glob *func_g,
/* blank module name to match all modules */
if (!mod_g->len) {
/* blank module globbing: modname xor exclude_mod */
- if ((!exclude_mod) != (!modname))
+ if (!exclude_mod != !modname)
goto func_match;
return 0;
}
- /* not matching the module */
- if (!modname || !mod_matches) {
- if (exclude_mod)
- goto func_match;
- else
- return 0;
- }
-
- if (mod_matches && exclude_mod)
+ /*
+ * exclude_mod is set to trace everything but the given
+ * module. If it is set and the module matches, then
+ * return 0. If it is not set, and the module doesn't match
+ * also return 0. Otherwise, check the function to see if
+ * that matches.
+ */
+ if (!mod_matches == !exclude_mod)
return 0;
-
func_match:
/* blank search means to match all funcs in the mod */
if (!func_g->len)
@@ -4146,9 +4144,9 @@ unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
int i, ret = -ENODEV;
int size;
- if (glob && (strcmp(glob, "*") == 0 || !strlen(glob)))
+ if (!glob || !strlen(glob) || !strcmp(glob, "*"))
func_g.search = NULL;
- else if (glob) {
+ else {
int not;
func_g.type = filter_parse_regex(glob, strlen(glob),
@@ -4258,6 +4256,14 @@ unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
return ret;
}
+void clear_ftrace_function_probes(struct trace_array *tr)
+{
+ struct ftrace_func_probe *probe, *n;
+
+ list_for_each_entry_safe(probe, n, &tr->func_probes, list)
+ unregister_ftrace_function_probe_func(NULL, tr, probe->probe_ops);
+}
+
static LIST_HEAD(ftrace_commands);
static DEFINE_MUTEX(ftrace_cmd_mutex);
@@ -4331,9 +4337,6 @@ static int ftrace_process_regex(struct ftrace_iterator *iter,
command = strsep(&next, ":");
- if (WARN_ON_ONCE(!tr))
- return -EINVAL;
-
mutex_lock(&ftrace_cmd_mutex);
list_for_each_entry(p, &ftrace_commands, list) {
if (strcmp(p->name, command) == 0) {
@@ -5057,7 +5060,7 @@ ftrace_graph_release(struct inode *inode, struct file *file)
}
out:
- kfree(fgd->new_hash);
+ free_ftrace_hash(fgd->new_hash);
kfree(fgd);
return ret;
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 80eda7d254ed..091e801145c9 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1558,7 +1558,7 @@ static __init int init_trace_selftests(void)
return 0;
}
-early_initcall(init_trace_selftests);
+core_initcall(init_trace_selftests);
#else
static inline int run_tracer_selftest(struct tracer *type)
{
@@ -1976,7 +1976,7 @@ static void __trace_find_cmdline(int pid, char comm[])
map = savedcmd->map_pid_to_cmdline[pid];
if (map != NO_CMDLINE_MAP)
- strcpy(comm, get_saved_cmdlines(map));
+ strlcpy(comm, get_saved_cmdlines(map), TASK_COMM_LEN);
else
strcpy(comm, "<...>");
}
@@ -2568,7 +2568,36 @@ static inline void ftrace_trace_stack(struct trace_array *tr,
void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
int pc)
{
- __ftrace_trace_stack(tr->trace_buffer.buffer, flags, skip, pc, NULL);
+ struct ring_buffer *buffer = tr->trace_buffer.buffer;
+
+ if (rcu_is_watching()) {
+ __ftrace_trace_stack(buffer, flags, skip, pc, NULL);
+ return;
+ }
+
+ /*
+ * When an NMI triggers, RCU is enabled via rcu_nmi_enter(),
+ * but if the above rcu_is_watching() failed, then the NMI
+ * triggered someplace critical, and rcu_irq_enter() should
+ * not be called from NMI.
+ */
+ if (unlikely(in_nmi()))
+ return;
+
+ /*
+ * It is possible that a function is being traced in a
+ * location that RCU is not watching. A call to
+ * rcu_irq_enter() will make sure that it is, but there's
+ * a few internal rcu functions that could be traced
+ * where that wont work either. In those cases, we just
+ * do nothing.
+ */
+ if (unlikely(rcu_irq_enter_disabled()))
+ return;
+
+ rcu_irq_enter_irqson();
+ __ftrace_trace_stack(buffer, flags, skip, pc, NULL);
+ rcu_irq_exit_irqson();
}
/**
@@ -3311,13 +3340,14 @@ static void test_cpu_buff_start(struct trace_iterator *iter)
if (!(iter->iter_flags & TRACE_FILE_ANNOTATE))
return;
- if (iter->started && cpumask_test_cpu(iter->cpu, iter->started))
+ if (cpumask_available(iter->started) &&
+ cpumask_test_cpu(iter->cpu, iter->started))
return;
if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries)
return;
- if (iter->started)
+ if (cpumask_available(iter->started))
cpumask_set_cpu(iter->cpu, iter->started);
/* Don't print started cpu buffer for the first entry of the trace */
@@ -6851,6 +6881,9 @@ ftrace_trace_snapshot_callback(struct trace_array *tr, struct ftrace_hash *hash,
char *number;
int ret;
+ if (!tr)
+ return -ENODEV;
+
/* hash funcs only work with set_ftrace_filter */
if (!enable)
return -EINVAL;
@@ -7549,6 +7582,7 @@ static int instance_rmdir(const char *name)
}
tracing_set_nop(tr);
+ clear_ftrace_function_probes(tr);
event_trace_del_tracer(tr);
ftrace_clear_pids(tr);
ftrace_destroy_function_files(tr);
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 291a1bca5748..39fd77330aab 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -980,6 +980,7 @@ register_ftrace_function_probe(char *glob, struct trace_array *tr,
extern int
unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
struct ftrace_probe_ops *ops);
+extern void clear_ftrace_function_probes(struct trace_array *tr);
int register_ftrace_command(struct ftrace_func_command *cmd);
int unregister_ftrace_command(struct ftrace_func_command *cmd);
@@ -998,6 +999,10 @@ static inline __init int unregister_ftrace_command(char *cmd_name)
{
return -EINVAL;
}
+static inline void clear_ftrace_function_probes(struct trace_array *tr)
+{
+}
+
/*
* The ops parameter passed in is usually undefined.
* This must be a macro.
diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h
index c203ac4df791..adcdbbeae010 100644
--- a/kernel/trace/trace_entries.h
+++ b/kernel/trace/trace_entries.h
@@ -348,14 +348,14 @@ FTRACE_ENTRY(hwlat, hwlat_entry,
__field( u64, duration )
__field( u64, outer_duration )
__field( u64, nmi_total_ts )
- __field_struct( struct timespec, timestamp )
- __field_desc( long, timestamp, tv_sec )
+ __field_struct( struct timespec64, timestamp )
+ __field_desc( s64, timestamp, tv_sec )
__field_desc( long, timestamp, tv_nsec )
__field( unsigned int, nmi_count )
__field( unsigned int, seqnum )
),
- F_printk("cnt:%u\tts:%010lu.%010lu\tinner:%llu\touter:%llunmi-ts:%llu\tnmi-count:%u\n",
+ F_printk("cnt:%u\tts:%010llu.%010lu\tinner:%llu\touter:%llunmi-ts:%llu\tnmi-count:%u\n",
__entry->seqnum,
__entry->tv_sec,
__entry->tv_nsec,
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index a3bddbfd0874..a0910c0cdf2e 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -654,6 +654,9 @@ ftrace_trace_onoff_callback(struct trace_array *tr, struct ftrace_hash *hash,
{
struct ftrace_probe_ops *ops;
+ if (!tr)
+ return -ENODEV;
+
/* we register both traceon and traceoff to this callback */
if (strcmp(cmd, "traceon") == 0)
ops = param ? &traceon_count_probe_ops : &traceon_probe_ops;
@@ -670,6 +673,9 @@ ftrace_stacktrace_callback(struct trace_array *tr, struct ftrace_hash *hash,
{
struct ftrace_probe_ops *ops;
+ if (!tr)
+ return -ENODEV;
+
ops = param ? &stacktrace_count_probe_ops : &stacktrace_probe_ops;
return ftrace_trace_probe_callback(tr, ops, hash, glob, cmd,
@@ -682,6 +688,9 @@ ftrace_dump_callback(struct trace_array *tr, struct ftrace_hash *hash,
{
struct ftrace_probe_ops *ops;
+ if (!tr)
+ return -ENODEV;
+
ops = &dump_probe_ops;
/* Only dump once. */
@@ -695,6 +704,9 @@ ftrace_cpudump_callback(struct trace_array *tr, struct ftrace_hash *hash,
{
struct ftrace_probe_ops *ops;
+ if (!tr)
+ return -ENODEV;
+
ops = &cpudump_probe_ops;
/* Only dump once. */
diff --git a/kernel/trace/trace_hwlat.c b/kernel/trace/trace_hwlat.c
index 21ea6ae77d93..d7c8e4ec3d9d 100644
--- a/kernel/trace/trace_hwlat.c
+++ b/kernel/trace/trace_hwlat.c
@@ -79,12 +79,12 @@ static u64 last_tracing_thresh = DEFAULT_LAT_THRESHOLD * NSEC_PER_USEC;
/* Individual latency samples are stored here when detected. */
struct hwlat_sample {
- u64 seqnum; /* unique sequence */
- u64 duration; /* delta */
- u64 outer_duration; /* delta (outer loop) */
- u64 nmi_total_ts; /* Total time spent in NMIs */
- struct timespec timestamp; /* wall time */
- int nmi_count; /* # NMIs during this sample */
+ u64 seqnum; /* unique sequence */
+ u64 duration; /* delta */
+ u64 outer_duration; /* delta (outer loop) */
+ u64 nmi_total_ts; /* Total time spent in NMIs */
+ struct timespec64 timestamp; /* wall time */
+ int nmi_count; /* # NMIs during this sample */
};
/* keep the global state somewhere. */
@@ -250,7 +250,7 @@ static int get_sample(void)
s.seqnum = hwlat_data.count;
s.duration = sample;
s.outer_duration = outer_sample;
- s.timestamp = CURRENT_TIME;
+ ktime_get_real_ts64(&s.timestamp);
s.nmi_total_ts = nmi_total_ts;
s.nmi_count = nmi_count;
trace_hwlat_sample(&s);
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 8485f6738a87..b53c8d369163 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -707,20 +707,16 @@ static int create_trace_kprobe(int argc, char **argv)
pr_info("Probe point is not specified.\n");
return -EINVAL;
}
- if (isdigit(argv[1][0])) {
- /* an address specified */
- ret = kstrtoul(&argv[1][0], 0, (unsigned long *)&addr);
- if (ret) {
- pr_info("Failed to parse address.\n");
- return ret;
- }
- } else {
+
+ /* try to parse an address. if that fails, try to read the
+ * input as a symbol. */
+ if (kstrtoul(argv[1], 0, (unsigned long *)&addr)) {
/* a symbol specified */
symbol = argv[1];
/* TODO: support .init module functions */
ret = traceprobe_split_symbol_offset(symbol, &offset);
if (ret) {
- pr_info("Failed to parse symbol.\n");
+ pr_info("Failed to parse either an address or a symbol.\n");
return ret;
}
if (offset && is_return &&
@@ -1535,6 +1531,11 @@ static __init int kprobe_trace_self_tests_init(void)
end:
release_all_trace_kprobes();
+ /*
+ * Wait for the optimizer work to finish. Otherwise it might fiddle
+ * with probes in already freed __init text.
+ */
+ wait_for_kprobe_optimizer();
if (warn)
pr_cont("NG: Some tests are failed. Please check them.\n");
else
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 02a4aeb22c47..08f9bab8089e 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -4,7 +4,6 @@
* Copyright (C) 2008 Red Hat Inc, Steven Rostedt <[email protected]>
*
*/
-
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/ftrace.h>
@@ -1161,11 +1160,11 @@ trace_hwlat_print(struct trace_iterator *iter, int flags,
trace_assign_type(field, entry);
- trace_seq_printf(s, "#%-5u inner/outer(us): %4llu/%-5llu ts:%ld.%09ld",
+ trace_seq_printf(s, "#%-5u inner/outer(us): %4llu/%-5llu ts:%lld.%09ld",
field->seqnum,
field->duration,
field->outer_duration,
- field->timestamp.tv_sec,
+ (long long)field->timestamp.tv_sec,
field->timestamp.tv_nsec);
if (field->nmi_count) {
@@ -1195,10 +1194,10 @@ trace_hwlat_raw(struct trace_iterator *iter, int flags,
trace_assign_type(field, iter->ent);
- trace_seq_printf(s, "%llu %lld %ld %09ld %u\n",
+ trace_seq_printf(s, "%llu %lld %lld %09ld %u\n",
field->duration,
field->outer_duration,
- field->timestamp.tv_sec,
+ (long long)field->timestamp.tv_sec,
field->timestamp.tv_nsec,
field->seqnum);
diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index 76aa04d4c925..b4a751e8f9d6 100644
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -409,7 +409,9 @@ static const struct file_operations stack_trace_fops = {
static int
stack_trace_filter_open(struct inode *inode, struct file *file)
{
- return ftrace_regex_open(&trace_ops, FTRACE_ITER_FILTER,
+ struct ftrace_ops *ops = inode->i_private;
+
+ return ftrace_regex_open(ops, FTRACE_ITER_FILTER,
inode, file);
}
@@ -476,7 +478,7 @@ static __init int stack_trace_init(void)
NULL, &stack_trace_fops);
trace_create_file("stack_trace_filter", 0444, d_tracer,
- NULL, &stack_trace_filter_fops);
+ &trace_ops, &stack_trace_filter_fops);
if (stack_trace_filter_buf[0])
ftrace_set_early_filter(&trace_ops, stack_trace_filter_buf, 1);