diff options
Diffstat (limited to 'kernel/trace/trace.c')
| -rw-r--r-- | kernel/trace/trace.c | 415 |
1 files changed, 279 insertions, 136 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 88de94da596b..47a44b055a1d 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -185,6 +185,7 @@ static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; static char *default_bootup_tracer; static bool allocate_snapshot; +static bool snapshot_at_boot; static int __init set_cmdline_ftrace(char *str) { @@ -230,12 +231,21 @@ static int __init boot_alloc_snapshot(char *str) __setup("alloc_snapshot", boot_alloc_snapshot); +static int __init boot_snapshot(char *str) +{ + snapshot_at_boot = true; + boot_alloc_snapshot(str); + return 1; +} +__setup("ftrace_boot_snapshot", boot_snapshot); + + static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; static int __init set_trace_boot_options(char *str) { strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); - return 0; + return 1; } __setup("trace_options=", set_trace_boot_options); @@ -246,12 +256,16 @@ static int __init set_trace_boot_clock(char *str) { strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE); trace_boot_clock = trace_boot_clock_buf; - return 0; + return 1; } __setup("trace_clock=", set_trace_boot_clock); static int __init set_tracepoint_printk(char *str) { + /* Ignore the "tp_printk_stop_on_boot" param */ + if (*str == '_') + return 0; + if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) tracepoint_printk = 1; return 1; @@ -707,13 +721,16 @@ int trace_pid_write(struct trace_pid_list *filtered_pids, pos = 0; ret = trace_get_user(&parser, ubuf, cnt, &pos); - if (ret < 0 || !trace_parser_loaded(&parser)) + if (ret < 0) break; read += ret; ubuf += ret; cnt -= ret; + if (!trace_parser_loaded(&parser)) + break; + ret = -EINVAL; if (kstrtoul(parser.buffer, 0, &val)) break; @@ -739,7 +756,6 @@ int trace_pid_write(struct trace_pid_list *filtered_pids, if (!nr_pids) { /* Cleared the list of pids */ trace_pid_list_free(pid_list); - read = ret; pid_list = NULL; } @@ -980,6 +996,8 @@ __buffer_unlock_commit(struct trace_buffer *buffer, struct ring_buffer_event *ev ring_buffer_write(buffer, event->array[0], &event->array[1]); /* Release the temp buffer */ this_cpu_dec(trace_buffered_event_cnt); + /* ring_buffer_unlock_commit() enables preemption */ + preempt_enable_notrace(); } else ring_buffer_unlock_commit(buffer, event); } @@ -1158,7 +1176,7 @@ void tracing_snapshot_cond(struct trace_array *tr, void *cond_data) EXPORT_SYMBOL_GPL(tracing_snapshot_cond); /** - * tracing_snapshot_cond_data - get the user data associated with a snapshot + * tracing_cond_snapshot_data - get the user data associated with a snapshot * @tr: The tracing instance * * When the user enables a conditional snapshot using @@ -1175,12 +1193,14 @@ void *tracing_cond_snapshot_data(struct trace_array *tr) { void *cond_data = NULL; + local_irq_disable(); arch_spin_lock(&tr->max_lock); if (tr->cond_snapshot) cond_data = tr->cond_snapshot->cond_data; arch_spin_unlock(&tr->max_lock); + local_irq_enable(); return cond_data; } @@ -1316,9 +1336,11 @@ int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, goto fail_unlock; } + local_irq_disable(); arch_spin_lock(&tr->max_lock); tr->cond_snapshot = cond_snapshot; arch_spin_unlock(&tr->max_lock); + local_irq_enable(); mutex_unlock(&trace_types_lock); @@ -1345,6 +1367,7 @@ int tracing_snapshot_cond_disable(struct trace_array *tr) { int ret = 0; + local_irq_disable(); arch_spin_lock(&tr->max_lock); if (!tr->cond_snapshot) @@ -1355,6 +1378,7 @@ int tracing_snapshot_cond_disable(struct trace_array *tr) } arch_spin_unlock(&tr->max_lock); + local_irq_enable(); return ret; } @@ -1468,10 +1492,12 @@ static int __init set_buf_size(char *str) if (!str) return 0; buf_size = memparse(str, &str); - /* nr_entries can not be zero */ - if (buf_size == 0) - return 0; - trace_buf_size = buf_size; + /* + * nr_entries can not be zero and the startup + * tests require some buffer space. Therefore + * ensure we have at least 4096 bytes of buffer. + */ + trace_buf_size = max(4096UL, buf_size); return 1; } __setup("trace_buf_size=", set_buf_size); @@ -1524,6 +1550,7 @@ static struct { { ktime_get_mono_fast_ns, "mono", 1 }, { ktime_get_raw_fast_ns, "mono_raw", 1 }, { ktime_get_boot_fast_ns, "boot", 1 }, + { ktime_get_tai_fast_ns, "tai", 1 }, ARCH_TRACE_CLOCKS }; @@ -2179,6 +2206,11 @@ static size_t tgid_map_max; #define SAVED_CMDLINES_DEFAULT 128 #define NO_CMDLINE_MAP UINT_MAX +/* + * Preemption must be disabled before acquiring trace_cmdline_lock. + * The various trace_arrays' max_lock must be acquired in a context + * where interrupt is disabled. + */ static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; struct saved_cmdlines_buffer { unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; @@ -2391,7 +2423,11 @@ static int trace_save_cmdline(struct task_struct *tsk) * the lock, but we also don't want to spin * nor do we want to disable interrupts, * so if we miss here, then better luck next time. + * + * This is called within the scheduler and wake up, so interrupts + * had better been disabled and run queue lock been held. */ + lockdep_assert_preemption_disabled(); if (!arch_spin_trylock(&trace_cmdline_lock)) return 0; @@ -2601,6 +2637,8 @@ unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status) trace_flags |= TRACE_FLAG_HARDIRQ; if (in_serving_softirq()) trace_flags |= TRACE_FLAG_SOFTIRQ; + if (softirq_count() >> (SOFTIRQ_SHIFT + 1)) + trace_flags |= TRACE_FLAG_BH_OFF; if (tif_need_resched()) trace_flags |= TRACE_FLAG_NEED_RESCHED; @@ -2745,8 +2783,8 @@ trace_event_buffer_lock_reserve(struct trace_buffer **current_rb, *current_rb = tr->array_buffer.buffer; if (!tr->no_filter_buffering_ref && - (trace_file->flags & (EVENT_FILE_FL_SOFT_DISABLED | EVENT_FILE_FL_FILTERED)) && - (entry = this_cpu_read(trace_buffered_event))) { + (trace_file->flags & (EVENT_FILE_FL_SOFT_DISABLED | EVENT_FILE_FL_FILTERED))) { + preempt_disable_notrace(); /* * Filtering is on, so try to use the per cpu buffer first. * This buffer will simulate a ring_buffer_event, @@ -2764,33 +2802,38 @@ trace_event_buffer_lock_reserve(struct trace_buffer **current_rb, * is still quicker than no copy on match, but having * to discard out of the ring buffer on a failed match. */ - int max_len = PAGE_SIZE - struct_size(entry, array, 1); + if ((entry = __this_cpu_read(trace_buffered_event))) { + int max_len = PAGE_SIZE - struct_size(entry, array, 1); - val = this_cpu_inc_return(trace_buffered_event_cnt); + val = this_cpu_inc_return(trace_buffered_event_cnt); - /* - * Preemption is disabled, but interrupts and NMIs - * can still come in now. If that happens after - * the above increment, then it will have to go - * back to the old method of allocating the event - * on the ring buffer, and if the filter fails, it - * will have to call ring_buffer_discard_commit() - * to remove it. - * - * Need to also check the unlikely case that the - * length is bigger than the temp buffer size. - * If that happens, then the reserve is pretty much - * guaranteed to fail, as the ring buffer currently - * only allows events less than a page. But that may - * change in the future, so let the ring buffer reserve - * handle the failure in that case. - */ - if (val == 1 && likely(len <= max_len)) { - trace_event_setup(entry, type, trace_ctx); - entry->array[0] = len; - return entry; + /* + * Preemption is disabled, but interrupts and NMIs + * can still come in now. If that happens after + * the above increment, then it will have to go + * back to the old method of allocating the event + * on the ring buffer, and if the filter fails, it + * will have to call ring_buffer_discard_commit() + * to remove it. + * + * Need to also check the unlikely case that the + * length is bigger than the temp buffer size. + * If that happens, then the reserve is pretty much + * guaranteed to fail, as the ring buffer currently + * only allows events less than a page. But that may + * change in the future, so let the ring buffer reserve + * handle the failure in that case. + */ + if (val == 1 && likely(len <= max_len)) { + trace_event_setup(entry, type, trace_ctx); + entry->array[0] = len; + /* Return with preemption disabled */ + return entry; + } + this_cpu_dec(trace_buffered_event_cnt); } - this_cpu_dec(trace_buffered_event_cnt); + /* __trace_buffer_lock_reserve() disables preemption */ + preempt_enable_notrace(); } entry = __trace_buffer_lock_reserve(*current_rb, type, len, @@ -2810,7 +2853,7 @@ trace_event_buffer_lock_reserve(struct trace_buffer **current_rb, } EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); -static DEFINE_SPINLOCK(tracepoint_iter_lock); +static DEFINE_RAW_SPINLOCK(tracepoint_iter_lock); static DEFINE_MUTEX(tracepoint_printk_mutex); static void output_printk(struct trace_event_buffer *fbuffer) @@ -2838,14 +2881,14 @@ static void output_printk(struct trace_event_buffer *fbuffer) event = &fbuffer->trace_file->event_call->event; - spin_lock_irqsave(&tracepoint_iter_lock, flags); + raw_spin_lock_irqsave(&tracepoint_iter_lock, flags); trace_seq_init(&iter->seq); iter->ent = fbuffer->entry; event_call->event.funcs->trace(iter, 0, event); trace_seq_putc(&iter->seq, 0); printk("%s", iter->seq.buffer); - spin_unlock_irqrestore(&tracepoint_iter_lock, flags); + raw_spin_unlock_irqrestore(&tracepoint_iter_lock, flags); } int tracepoint_printk_sysctl(struct ctl_table *table, int write, @@ -3077,17 +3120,17 @@ void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, } /* - * When an NMI triggers, RCU is enabled via rcu_nmi_enter(), + * When an NMI triggers, RCU is enabled via ct_nmi_enter(), * but if the above rcu_is_watching() failed, then the NMI - * triggered someplace critical, and rcu_irq_enter() should + * triggered someplace critical, and ct_irq_enter() should * not be called from NMI. */ if (unlikely(in_nmi())) return; - rcu_irq_enter_irqson(); + ct_irq_enter_irqson(); __ftrace_trace_stack(buffer, trace_ctx, skip, NULL); - rcu_irq_exit_irqson(); + ct_irq_exit_irqson(); } /** @@ -3207,7 +3250,7 @@ struct trace_buffer_struct { char buffer[4][TRACE_BUF_SIZE]; }; -static struct trace_buffer_struct *trace_percpu_buffer; +static struct trace_buffer_struct __percpu *trace_percpu_buffer; /* * This allows for lockless recording. If we're nested too deeply, then @@ -3217,7 +3260,7 @@ static char *get_trace_buf(void) { struct trace_buffer_struct *buffer = this_cpu_ptr(trace_percpu_buffer); - if (!buffer || buffer->nesting >= 4) + if (!trace_percpu_buffer || buffer->nesting >= 4) return NULL; buffer->nesting++; @@ -3236,7 +3279,7 @@ static void put_trace_buf(void) static int alloc_percpu_trace_buffer(void) { - struct trace_buffer_struct *buffers; + struct trace_buffer_struct __percpu *buffers; if (trace_percpu_buffer) return 0; @@ -3648,12 +3691,17 @@ static char *trace_iter_expand_format(struct trace_iterator *iter) } /* Returns true if the string is safe to dereference from an event */ -static bool trace_safe_str(struct trace_iterator *iter, const char *str) +static bool trace_safe_str(struct trace_iterator *iter, const char *str, + bool star, int len) { unsigned long addr = (unsigned long)str; struct trace_event *trace_event; struct trace_event_call *event; + /* Ignore strings with no length */ + if (star && !len) + return true; + /* OK if part of the event data */ if ((addr >= (unsigned long)iter->ent) && (addr < (unsigned long)iter->ent + iter->ent_size)) @@ -3839,7 +3887,7 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt, * instead. See samples/trace_events/trace-events-sample.h * for reference. */ - if (WARN_ONCE(!trace_safe_str(iter, str), + if (WARN_ONCE(!trace_safe_str(iter, str, star, len), "fmt: '%s' current_buffer: '%s'", fmt, show_buffer(&iter->seq))) { int ret; @@ -4183,7 +4231,7 @@ unsigned long trace_total_entries(struct trace_array *tr) static void print_lat_help_header(struct seq_file *m) { seq_puts(m, "# _------=> CPU# \n" - "# / _-----=> irqs-off \n" + "# / _-----=> irqs-off/BH-disabled\n" "# | / _----=> need-resched \n" "# || / _---=> hardirq/softirq \n" "# ||| / _--=> preempt-depth \n" @@ -4219,12 +4267,12 @@ static void print_func_help_header_irq(struct array_buffer *buf, struct seq_file unsigned int flags) { bool tgid = flags & TRACE_ITER_RECORD_TGID; - const char *space = " "; + static const char space[] = " "; int prec = tgid ? 12 : 2; print_event_info(buf, m); - seq_printf(m, "# %.*s _-----=> irqs-off\n", prec, space); + seq_printf(m, "# %.*s _-----=> irqs-off/BH-disabled\n", prec, space); seq_printf(m, "# %.*s / _----=> need-resched\n", prec, space); seq_printf(m, "# %.*s| / _---=> hardirq/softirq\n", prec, space); seq_printf(m, "# %.*s|| / _--=> preempt-depth\n", prec, space); @@ -4243,9 +4291,7 @@ print_trace_header(struct seq_file *m, struct trace_iterator *iter) struct tracer *type = iter->trace; unsigned long entries; unsigned long total; - const char *name = "preemption"; - - name = type->name; + const char *name = type->name; get_total_entries(buf, &total, &entries); @@ -4259,17 +4305,11 @@ print_trace_header(struct seq_file *m, struct trace_iterator *iter) entries, total, buf->cpu, -#if defined(CONFIG_PREEMPT_NONE) - "server", -#elif defined(CONFIG_PREEMPT_VOLUNTARY) - "desktop", -#elif defined(CONFIG_PREEMPT) - "preempt", -#elif defined(CONFIG_PREEMPT_RT) - "preempt_rt", -#else + preempt_model_none() ? "server" : + preempt_model_voluntary() ? "desktop" : + preempt_model_full() ? "preempt" : + preempt_model_rt() ? "preempt_rt" : "unknown", -#endif /* These are reserved for later use */ 0, 0, 0, 0); #ifdef CONFIG_SMP @@ -4834,6 +4874,12 @@ int tracing_open_generic_tr(struct inode *inode, struct file *filp) return 0; } +static int tracing_mark_open(struct inode *inode, struct file *filp) +{ + stream_open(inode, filp); + return tracing_open_generic_tr(inode, filp); +} + static int tracing_release(struct inode *inode, struct file *file) { struct trace_array *tr = inode->i_private; @@ -5439,7 +5485,7 @@ static const char readme_msg[] = " error_log\t- error log for failed commands (that support it)\n" " buffer_size_kb\t- view and modify size of per cpu buffer\n" " buffer_total_size_kb - view total size of all cpu buffers\n\n" - " trace_clock\t\t-change the clock used to order events\n" + " trace_clock\t\t- change the clock used to order events\n" " local: Per cpu clock but may not be synced across CPUs\n" " global: Synced across CPUs but slows tracing down.\n" " counter: Not a clock, but just an increment\n" @@ -5448,7 +5494,7 @@ static const char readme_msg[] = #ifdef CONFIG_X86_64 " x86-tsc: TSC cycle counter\n" #endif - "\n timestamp_mode\t-view the mode used to timestamp events\n" + "\n timestamp_mode\t- view the mode used to timestamp events\n" " delta: Delta difference against a buffer-wide timestamp\n" " absolute: Absolute (standalone) timestamp\n" "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n" @@ -5538,13 +5584,13 @@ static const char readme_msg[] = #endif #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) "\t accepts: event-definitions (one definition per line)\n" - "\t Format: p[:[<group>/]<event>] <place> [<args>]\n" - "\t r[maxactive][:[<group>/]<event>] <place> [<args>]\n" + "\t Format: p[:[<group>/][<event>]] <place> [<args>]\n" + "\t r[maxactive][:[<group>/][<event>]] <place> [<args>]\n" #ifdef CONFIG_HIST_TRIGGERS "\t s:[synthetic/]<event> <field> [<field>]\n" #endif - "\t e[:[<group>/]<event>] <attached-group>.<attached-event> [<args>]\n" - "\t -:[<group>/]<event>\n" + "\t e[:[<group>/][<event>]] <attached-group>.<attached-event> [<args>]\n" + "\t -:[<group>/][<event>]\n" #ifdef CONFIG_KPROBE_EVENTS "\t place: [<module>:]<symbol>[+<offset>]|<memaddr>\n" "place (kretprobe): [<module>:]<symbol>[+<offset>]%return|<memaddr>\n" @@ -5635,7 +5681,7 @@ static const char readme_msg[] = "\t - a numeric literal: e.g. ms_per_sec=1000,\n" "\t - an arithmetic expression: e.g. time_secs=current_timestamp/1000\n" "\n" - "\t hist trigger aritmethic expressions support addition(+), subtraction(-),\n" + "\t hist trigger arithmetic expressions support addition(+), subtraction(-),\n" "\t multiplication(*) and division(/) operators. An operand can be either a\n" "\t variable reference, field or numeric literal.\n" "\n" @@ -5859,9 +5905,11 @@ tracing_saved_cmdlines_size_read(struct file *filp, char __user *ubuf, char buf[64]; int r; + preempt_disable(); arch_spin_lock(&trace_cmdline_lock); r = scnprintf(buf, sizeof(buf), "%u\n", savedcmd->cmdline_num); arch_spin_unlock(&trace_cmdline_lock); + preempt_enable(); return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); } @@ -5886,10 +5934,12 @@ static int tracing_resize_saved_cmdlines(unsigned int val) return -ENOMEM; } + preempt_disable(); arch_spin_lock(&trace_cmdline_lock); savedcmd_temp = savedcmd; savedcmd = s; arch_spin_unlock(&trace_cmdline_lock); + preempt_enable(); free_saved_cmdlines_buffer(savedcmd_temp); return 0; @@ -6296,12 +6346,18 @@ static void tracing_set_nop(struct trace_array *tr) tr->current_trace = &nop_trace; } +static bool tracer_options_updated; + static void add_tracer_options(struct trace_array *tr, struct tracer *t) { /* Only enable if the directory has been created already. */ if (!tr->dir) return; + /* Only create trace option files after update_tracer_options finish */ + if (!tracer_options_updated) + return; + create_trace_option_files(tr, t); } @@ -6336,10 +6392,12 @@ int tracing_set_tracer(struct trace_array *tr, const char *buf) #ifdef CONFIG_TRACER_SNAPSHOT if (t->use_max_tr) { + local_irq_disable(); arch_spin_lock(&tr->max_lock); if (tr->cond_snapshot) ret = -EBUSY; arch_spin_unlock(&tr->max_lock); + local_irq_enable(); if (ret) goto out; } @@ -6370,12 +6428,12 @@ int tracing_set_tracer(struct trace_array *tr, const char *buf) if (tr->current_trace->reset) tr->current_trace->reset(tr); +#ifdef CONFIG_TRACER_MAX_TRACE + had_max_tr = tr->current_trace->use_max_tr; + /* Current trace needs to be nop_trace before synchronize_rcu */ tr->current_trace = &nop_trace; -#ifdef CONFIG_TRACER_MAX_TRACE - had_max_tr = tr->allocated_snapshot; - if (had_max_tr && !t->use_max_tr) { /* * We need to make sure that the update_max_tr sees that @@ -6387,14 +6445,14 @@ int tracing_set_tracer(struct trace_array *tr, const char *buf) synchronize_rcu(); free_snapshot(tr); } -#endif -#ifdef CONFIG_TRACER_MAX_TRACE - if (t->use_max_tr && !had_max_tr) { + if (t->use_max_tr && !tr->allocated_snapshot) { ret = tracing_alloc_snapshot_instance(tr); if (ret < 0) goto out; } +#else + tr->current_trace = &nop_trace; #endif if (t->init) { @@ -6418,7 +6476,7 @@ tracing_set_trace_write(struct file *filp, const char __user *ubuf, { struct trace_array *tr = filp->private_data; char buf[MAX_TRACER_SIZE+1]; - int i; + char *name; size_t ret; int err; @@ -6432,11 +6490,9 @@ tracing_set_trace_write(struct file *filp, const char __user *ubuf, buf[cnt] = 0; - /* strip ending whitespace. */ - for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) - buf[i] = 0; + name = strim(buf); - err = tracing_set_tracer(tr, buf); + err = tracing_set_tracer(tr, name); if (err) return err; @@ -6718,10 +6774,9 @@ waitagain: cnt = PAGE_SIZE - 1; /* reset all but tr, trace, and overruns */ - memset_startat(iter, 0, seq); + trace_iterator_reset(iter); cpumask_clear(iter->started); trace_seq_init(&iter->seq); - iter->pos = -1; trace_event_read_lock(); trace_access_lock(iter->cpu_file); @@ -7110,9 +7165,6 @@ tracing_mark_write(struct file *filp, const char __user *ubuf, if (tt) event_triggers_post_call(tr->trace_marker_file, tt); - if (written > 0) - *fpos += written; - return written; } @@ -7171,9 +7223,6 @@ tracing_mark_raw_write(struct file *filp, const char __user *ubuf, __buffer_unlock_commit(buffer, event); - if (written > 0) - *fpos += written; - return written; } @@ -7410,10 +7459,12 @@ tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, goto out; } + local_irq_disable(); arch_spin_lock(&tr->max_lock); if (tr->cond_snapshot) ret = -EBUSY; arch_spin_unlock(&tr->max_lock); + local_irq_enable(); if (ret) goto out; @@ -7573,16 +7624,14 @@ static const struct file_operations tracing_free_buffer_fops = { }; static const struct file_operations tracing_mark_fops = { - .open = tracing_open_generic_tr, + .open = tracing_mark_open, .write = tracing_mark_write, - .llseek = generic_file_llseek, .release = tracing_release_generic_tr, }; static const struct file_operations tracing_mark_raw_fops = { - .open = tracing_open_generic_tr, + .open = tracing_mark_open, .write = tracing_mark_raw_write, - .llseek = generic_file_llseek, .release = tracing_release_generic_tr, }; @@ -7713,7 +7762,7 @@ const struct file_operations trace_min_max_fops = { struct err_info { const char **errs; /* ptr to loc-specific array of err strings */ u8 type; /* index into errs -> specific err string */ - u8 pos; /* MAX_FILTER_STR_VAL = 256 */ + u16 pos; /* caret position */ u64 ts; }; @@ -7721,25 +7770,52 @@ struct tracing_log_err { struct list_head list; struct err_info info; char loc[TRACING_LOG_LOC_MAX]; /* err location */ - char cmd[MAX_FILTER_STR_VAL]; /* what caused err */ + char *cmd; /* what caused err */ }; static DEFINE_MUTEX(tracing_err_log_lock); -static struct tracing_log_err *get_tracing_log_err(struct trace_array *tr) +static struct tracing_log_err *alloc_tracing_log_err(int len) +{ + struct tracing_log_err *err; + + err = kzalloc(sizeof(*err), GFP_KERNEL); + if (!err) + return ERR_PTR(-ENOMEM); + + err->cmd = kzalloc(len, GFP_KERNEL); + if (!err->cmd) { + kfree(err); + return ERR_PTR(-ENOMEM); + } + + return err; +} + +static void free_tracing_log_err(struct tracing_log_err *err) +{ + kfree(err->cmd); + kfree(err); +} + +static struct tracing_log_err *get_tracing_log_err(struct trace_array *tr, + int len) { struct tracing_log_err *err; if (tr->n_err_log_entries < TRACING_LOG_ERRS_MAX) { - err = kzalloc(sizeof(*err), GFP_KERNEL); - if (!err) - err = ERR_PTR(-ENOMEM); - tr->n_err_log_entries++; + err = alloc_tracing_log_err(len); + if (PTR_ERR(err) != -ENOMEM) + tr->n_err_log_entries++; return err; } err = list_first_entry(&tr->err_log, struct tracing_log_err, list); + kfree(err->cmd); + err->cmd = kzalloc(len, GFP_KERNEL); + if (!err->cmd) + return ERR_PTR(-ENOMEM); list_del(&err->list); return err; @@ -7800,22 +7876,25 @@ unsigned int err_pos(char *cmd, const char *str) */ void tracing_log_err(struct trace_array *tr, const char *loc, const char *cmd, - const char **errs, u8 type, u8 pos) + const char **errs, u8 type, u16 pos) { struct tracing_log_err *err; + int len = 0; if (!tr) tr = &global_trace; + len += sizeof(CMD_PREFIX) + 2 * sizeof("\n") + strlen(cmd) + 1; + mutex_lock(&tracing_err_log_lock); - err = get_tracing_log_err(tr); + err = get_tracing_log_err(tr, len); if (PTR_ERR(err) == -ENOMEM) { mutex_unlock(&tracing_err_log_lock); return; } snprintf(err->loc, TRACING_LOG_LOC_MAX, "%s: error: ", loc); - snprintf(err->cmd, MAX_FILTER_STR_VAL,"\n" CMD_PREFIX "%s\n", cmd); + snprintf(err->cmd, len, "\n" CMD_PREFIX "%s\n", cmd); err->info.errs = errs; err->info.type = type; @@ -7833,7 +7912,7 @@ static void clear_tracing_err_log(struct trace_array *tr) mutex_lock(&tracing_err_log_lock); list_for_each_entry_safe(err, next, &tr->err_log, list) { list_del(&err->list); - kfree(err); + free_tracing_log_err(err); } tr->n_err_log_entries = 0; @@ -7861,9 +7940,9 @@ static void tracing_err_log_seq_stop(struct seq_file *m, void *v) mutex_unlock(&tracing_err_log_lock); } -static void tracing_err_log_show_pos(struct seq_file *m, u8 pos) +static void tracing_err_log_show_pos(struct seq_file *m, u16 pos) { - u8 i; + u16 i; for (i = 0; i < sizeof(CMD_PREFIX) - 1; i++) seq_putc(m, ' '); @@ -8083,6 +8162,12 @@ static int tracing_buffers_release(struct inode *inode, struct file *file) __trace_array_put(iter->tr); + iter->wait_index++; + /* Make sure the waiters see the new wait_index */ + smp_wmb(); + + ring_buffer_wake_waiters(iter->array_buffer->buffer, iter->cpu_file); + if (info->spare) ring_buffer_free_read_page(iter->array_buffer->buffer, info->spare_cpu, info->spare); @@ -8236,6 +8321,8 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos, /* did we read anything? */ if (!spd.nr_pages) { + long wait_index; + if (ret) goto out; @@ -8243,10 +8330,21 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos, if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) goto out; + wait_index = READ_ONCE(iter->wait_index); + ret = wait_on_pipe(iter, iter->tr->buffer_percent); if (ret) goto out; + /* No need to wait after waking up when tracing is off */ + if (!tracer_tracing_is_on(iter->tr)) + goto out; + + /* Make sure we see the new wait_index */ + smp_rmb(); + if (wait_index != iter->wait_index) + goto out; + goto again; } @@ -8257,12 +8355,34 @@ out: return ret; } +/* An ioctl call with cmd 0 to the ring buffer file will wake up all waiters */ +static long tracing_buffers_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + struct ftrace_buffer_info *info = file->private_data; + struct trace_iterator *iter = &info->iter; + + if (cmd) + return -ENOIOCTLCMD; + + mutex_lock(&trace_types_lock); + + iter->wait_index++; + /* Make sure the waiters see the new wait_index */ + smp_wmb(); + + ring_buffer_wake_waiters(iter->array_buffer->buffer, iter->cpu_file); + + mutex_unlock(&trace_types_lock); + return 0; +} + static const struct file_operations tracing_buffers_fops = { .open = tracing_buffers_open, .read = tracing_buffers_read, .poll = tracing_buffers_poll, .release = tracing_buffers_release, .splice_read = tracing_buffers_splice_read, + .unlocked_ioctl = tracing_buffers_ioctl, .llseek = no_llseek, }; @@ -8951,6 +9071,8 @@ rb_simple_write(struct file *filp, const char __user *ubuf, tracer_tracing_off(tr); if (tr->current_trace->stop) tr->current_trace->stop(tr); + /* Wake up any waiters */ + ring_buffer_wake_waiters(buffer, RING_BUFFER_ALL_CPUS); } mutex_unlock(&trace_types_lock); } @@ -9047,6 +9169,16 @@ allocate_trace_buffer(struct trace_array *tr, struct array_buffer *buf, int size return 0; } +static void free_trace_buffer(struct array_buffer *buf) +{ + if (buf->buffer) { + ring_buffer_free(buf->buffer); + buf->buffer = NULL; + free_percpu(buf->data); + buf->data = NULL; + } +} + static int allocate_trace_buffers(struct trace_array *tr, int size) { int ret; @@ -9059,10 +9191,7 @@ static int allocate_trace_buffers(struct trace_array *tr, int size) ret = allocate_trace_buffer(tr, &tr->max_buffer, allocate_snapshot ? size : 1); if (MEM_FAIL(ret, "Failed to allocate trace buffer\n")) { - ring_buffer_free(tr->array_buffer.buffer); - tr->array_buffer.buffer = NULL; - free_percpu(tr->array_buffer.data); - tr->array_buffer.data = NULL; + free_trace_buffer(&tr->array_buffer); return -ENOMEM; } tr->allocated_snapshot = allocate_snapshot; @@ -9077,16 +9206,6 @@ static int allocate_trace_buffers(struct trace_array *tr, int size) return 0; } -static void free_trace_buffer(struct array_buffer *buf) -{ - if (buf->buffer) { - ring_buffer_free(buf->buffer); - buf->buffer = NULL; - free_percpu(buf->data); - buf->data = NULL; - } -} - static void free_trace_buffers(struct trace_array *tr) { if (!tr) @@ -9119,6 +9238,7 @@ static void __update_tracer_options(struct trace_array *tr) static void update_tracer_options(struct trace_array *tr) { mutex_lock(&trace_types_lock); + tracer_options_updated = true; __update_tracer_options(tr); mutex_unlock(&trace_types_lock); } @@ -9551,6 +9671,7 @@ extern struct trace_eval_map *__stop_ftrace_eval_maps[]; static struct workqueue_struct *eval_map_wq __initdata; static struct work_struct eval_map_work __initdata; +static struct work_struct tracerfs_init_work __initdata; static void __init eval_map_work_func(struct work_struct *work) { @@ -9576,6 +9697,8 @@ static int __init trace_eval_init(void) return 0; } +subsys_initcall(trace_eval_init); + static int __init trace_eval_sync(void) { /* Make sure the eval map updates are finished */ @@ -9658,15 +9781,8 @@ static struct notifier_block trace_module_nb = { }; #endif /* CONFIG_MODULES */ -static __init int tracer_init_tracefs(void) +static __init void tracer_init_tracefs_work_func(struct work_struct *work) { - int ret; - - trace_access_lock_init(); - - ret = tracing_init_dentry(); - if (ret) - return 0; event_trace_init(); @@ -9688,8 +9804,6 @@ static __init int tracer_init_tracefs(void) trace_create_file("saved_tgids", TRACE_MODE_READ, NULL, NULL, &tracing_saved_tgids_fops); - trace_eval_init(); - trace_create_eval_file(NULL); #ifdef CONFIG_MODULES @@ -9704,6 +9818,26 @@ static __init int tracer_init_tracefs(void) create_trace_instances(NULL); update_tracer_options(&global_trace); +} + +static __init int tracer_init_tracefs(void) +{ + int ret; + + trace_access_lock_init(); + + ret = tracing_init_dentry(); + if (ret) + return 0; + + if (eval_map_wq) { + INIT_WORK(&tracerfs_init_work, tracer_init_tracefs_work_func); + queue_work(eval_map_wq, &tracerfs_init_work); + } else { + tracer_init_tracefs_work_func(NULL); + } + + rv_init_interface(); return 0; } @@ -9797,6 +9931,12 @@ void trace_init_global_iter(struct trace_iterator *iter) /* Output in nanoseconds only if we are using a clock in nanoseconds. */ if (trace_clocks[iter->tr->clock_id].in_ns) iter->iter_flags |= TRACE_FILE_TIME_IN_NS; + + /* Can not use kmalloc for iter.temp and iter.fmt */ + iter->temp = static_temp_buf; + iter->temp_size = STATIC_TEMP_BUF_SIZE; + iter->fmt = static_fmt_buf; + iter->fmt_size = STATIC_FMT_BUF_SIZE; } void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) @@ -9829,11 +9969,6 @@ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) /* Simulate the iterator */ trace_init_global_iter(&iter); - /* Can not use kmalloc for iter.temp and iter.fmt */ - iter.temp = static_temp_buf; - iter.temp_size = STATIC_TEMP_BUF_SIZE; - iter.fmt = static_fmt_buf; - iter.fmt_size = STATIC_FMT_BUF_SIZE; for_each_tracing_cpu(cpu) { atomic_inc(&per_cpu_ptr(iter.array_buffer->data, cpu)->disabled); @@ -10024,7 +10159,7 @@ __init static int tracer_alloc_buffers(void) * buffer. The memory will be removed once the "instance" is removed. */ ret = cpuhp_setup_state_multi(CPUHP_TRACE_RB_PREPARE, - "trace/RB:preapre", trace_rb_cpu_prepare, + "trace/RB:prepare", trace_rb_cpu_prepare, NULL); if (ret < 0) goto out_free_cpumask; @@ -10109,6 +10244,14 @@ out: return ret; } +void __init ftrace_boot_snapshot(void) +{ + if (snapshot_at_boot) { + tracing_snapshot(); + internal_trace_puts("** Boot snapshot taken **\n"); + } +} + void __init early_trace_init(void) { if (tracepoint_printk) { |