X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=kernel%2Ftrace%2Ftrace.c;h=45068269ebb1746673f23c20b146ca9104a0b325;hb=49557e620339cb134127b5bfbcfecc06b77d0232;hp=0f0881676dc98f9cfdb0ac622d01ef9d6a24944d;hpb=5d4a9dba2d7fbab69f00dedd430d1788834a055a;p=safe%2Fjmp%2Flinux-2.6 diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 0f08816..4506826 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -125,13 +125,13 @@ int ftrace_dump_on_oops; static int tracing_set_tracer(const char *buf); -#define BOOTUP_TRACER_SIZE 100 -static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata; +#define MAX_TRACER_SIZE 100 +static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; static char *default_bootup_tracer; static int __init set_ftrace(char *str) { - strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE); + strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); default_bootup_tracer = bootup_tracer_buf; /* We are using ftrace early, expand it */ ring_buffer_expanded = 1; @@ -169,10 +169,11 @@ static struct trace_array global_trace; static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); -int filter_current_check_discard(struct ftrace_event_call *call, void *rec, +int filter_current_check_discard(struct ring_buffer *buffer, + struct ftrace_event_call *call, void *rec, struct ring_buffer_event *event) { - return filter_check_discard(call, rec, global_trace.buffer, event); + return filter_check_discard(call, rec, buffer, event); } EXPORT_SYMBOL_GPL(filter_current_check_discard); @@ -241,13 +242,6 @@ static struct tracer *trace_types __read_mostly; static struct tracer *current_trace __read_mostly; /* - * max_tracer_type_len is used to simplify the allocating of - * buffers to read userspace tracer names. We keep track of - * the longest tracer name registered. - */ -static int max_tracer_type_len; - -/* * trace_types_lock is used to protect the trace_types list. * This lock is also used to keep user access serialized. * Accesses from userspace will grab this lock while userspace @@ -263,6 +257,9 @@ unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | TRACE_ITER_GRAPH_TIME; +static int trace_stop_count; +static DEFINE_SPINLOCK(tracing_start_lock); + /** * trace_wake_up - wake up tasks waiting for trace input * @@ -271,12 +268,18 @@ unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | */ void trace_wake_up(void) { + int cpu; + + if (trace_flags & TRACE_ITER_BLOCK) + return; /* * The runqueue_is_locked() can fail, but this is the best we * have for now: */ - if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked()) + cpu = get_cpu(); + if (!runqueue_is_locked(cpu)) wake_up(&trace_wait); + put_cpu(); } static int __init set_buf_size(char *str) @@ -335,6 +338,112 @@ static struct { int trace_clock_id; +/* + * trace_parser_get_init - gets the buffer for trace parser + */ +int trace_parser_get_init(struct trace_parser *parser, int size) +{ + memset(parser, 0, sizeof(*parser)); + + parser->buffer = kmalloc(size, GFP_KERNEL); + if (!parser->buffer) + return 1; + + parser->size = size; + return 0; +} + +/* + * trace_parser_put - frees the buffer for trace parser + */ +void trace_parser_put(struct trace_parser *parser) +{ + kfree(parser->buffer); +} + +/* + * trace_get_user - reads the user input string separated by space + * (matched by isspace(ch)) + * + * For each string found the 'struct trace_parser' is updated, + * and the function returns. + * + * Returns number of bytes read. + * + * See kernel/trace/trace.h for 'struct trace_parser' details. + */ +int trace_get_user(struct trace_parser *parser, const char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + char ch; + size_t read = 0; + ssize_t ret; + + if (!*ppos) + trace_parser_clear(parser); + + ret = get_user(ch, ubuf++); + if (ret) + goto out; + + read++; + cnt--; + + /* + * The parser is not finished with the last write, + * continue reading the user input without skipping spaces. + */ + if (!parser->cont) { + /* skip white space */ + while (cnt && isspace(ch)) { + ret = get_user(ch, ubuf++); + if (ret) + goto out; + read++; + cnt--; + } + + /* only spaces were written */ + if (isspace(ch)) { + *ppos += read; + ret = read; + goto out; + } + + parser->idx = 0; + } + + /* read the non-space input */ + while (cnt && !isspace(ch)) { + if (parser->idx < parser->size - 1) + parser->buffer[parser->idx++] = ch; + else { + ret = -EINVAL; + goto out; + } + ret = get_user(ch, ubuf++); + if (ret) + goto out; + read++; + cnt--; + } + + /* We either got finished input or we have to wait for another call. */ + if (isspace(ch)) { + parser->buffer[parser->idx] = 0; + parser->cont = false; + } else { + parser->cont = true; + parser->buffer[parser->idx++] = ch; + } + + *ppos += read; + ret = read; + +out: + return ret; +} + ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) { int len; @@ -407,19 +516,22 @@ static void __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) { struct trace_array_cpu *data = tr->data[cpu]; + struct trace_array_cpu *max_data = tr->data[cpu]; max_tr.cpu = cpu; max_tr.time_start = data->preempt_timestamp; - data = max_tr.data[cpu]; - data->saved_latency = tracing_max_latency; + max_data = max_tr.data[cpu]; + max_data->saved_latency = tracing_max_latency; + max_data->critical_start = data->critical_start; + max_data->critical_end = data->critical_end; memcpy(data->comm, tsk->comm, TASK_COMM_LEN); - data->pid = tsk->pid; - data->uid = task_uid(tsk); - data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; - data->policy = tsk->policy; - data->rt_priority = tsk->rt_priority; + max_data->pid = tsk->pid; + max_data->uid = task_uid(tsk); + max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; + max_data->policy = tsk->policy; + max_data->rt_priority = tsk->rt_priority; /* record this tasks comm */ tracing_record_cmdline(tsk); @@ -439,16 +551,15 @@ update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) { struct ring_buffer *buf = tr->buffer; + if (trace_stop_count) + return; + WARN_ON_ONCE(!irqs_disabled()); __raw_spin_lock(&ftrace_max_lock); tr->buffer = max_tr.buffer; max_tr.buffer = buf; - ftrace_disable_cpu(); - ring_buffer_reset(tr->buffer); - ftrace_enable_cpu(); - __update_max_tr(tr, tsk, cpu); __raw_spin_unlock(&ftrace_max_lock); } @@ -466,17 +577,30 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) { int ret; + if (trace_stop_count) + return; + WARN_ON_ONCE(!irqs_disabled()); __raw_spin_lock(&ftrace_max_lock); ftrace_disable_cpu(); - ring_buffer_reset(max_tr.buffer); ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); + if (ret == -EBUSY) { + /* + * We failed to swap the buffer due to a commit taking + * place on this CPU. We fail to record, but we reset + * the max trace buffer (no one writes directly to it) + * and flag that it failed. + */ + trace_array_printk(&max_tr, _THIS_IP_, + "Failed to swap buffers due to commit in progress\n"); + } + ftrace_enable_cpu(); - WARN_ON_ONCE(ret && ret != -EAGAIN); + WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); __update_max_tr(tr, tsk, cpu); __raw_spin_unlock(&ftrace_max_lock); @@ -494,7 +618,6 @@ __releases(kernel_lock) __acquires(kernel_lock) { struct tracer *t; - int len; int ret = 0; if (!type->name) { @@ -502,6 +625,11 @@ __acquires(kernel_lock) return -1; } + if (strlen(type->name) > MAX_TRACER_SIZE) { + pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); + return -1; + } + /* * When this gets called we hold the BKL which means that * preemption is disabled. Various trace selftests however @@ -516,7 +644,7 @@ __acquires(kernel_lock) for (t = trace_types; t; t = t->next) { if (strcmp(type->name, t->name) == 0) { /* already found */ - pr_info("Trace %s already registered\n", + pr_info("Tracer %s already registered\n", type->name); ret = -1; goto out; @@ -538,7 +666,6 @@ __acquires(kernel_lock) if (type->selftest && !tracing_selftest_disabled) { struct tracer *saved_tracer = current_trace; struct trace_array *tr = &global_trace; - int i; /* * Run a selftest on this tracer. @@ -547,8 +674,7 @@ __acquires(kernel_lock) * internal tracing to verify that everything is in order. * If we fail, we do not register this tracer. */ - for_each_tracing_cpu(i) - tracing_reset(tr, i); + tracing_reset_online_cpus(tr); current_trace = type; /* the test is responsible for initializing and enabling */ @@ -561,8 +687,7 @@ __acquires(kernel_lock) goto out; } /* Only reset on passing, to avoid touching corrupted buffers */ - for_each_tracing_cpu(i) - tracing_reset(tr, i); + tracing_reset_online_cpus(tr); printk(KERN_CONT "PASSED\n"); } @@ -570,9 +695,6 @@ __acquires(kernel_lock) type->next = trace_types; trace_types = type; - len = strlen(type->name); - if (len > max_tracer_type_len) - max_tracer_type_len = len; out: tracing_selftest_running = false; @@ -581,7 +703,7 @@ __acquires(kernel_lock) if (ret || !default_bootup_tracer) goto out_unlock; - if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE)) + if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) goto out_unlock; printk(KERN_INFO "Starting tracer '%s'\n", type->name); @@ -603,14 +725,13 @@ __acquires(kernel_lock) void unregister_tracer(struct tracer *type) { struct tracer **t; - int len; mutex_lock(&trace_types_lock); for (t = &trace_types; *t; t = &(*t)->next) { if (*t == type) goto found; } - pr_info("Trace %s not registered\n", type->name); + pr_info("Tracer %s not registered\n", type->name); goto out; found: @@ -623,35 +744,46 @@ void unregister_tracer(struct tracer *type) current_trace->stop(&global_trace); current_trace = &nop_trace; } - - if (strlen(type->name) != max_tracer_type_len) - goto out; - - max_tracer_type_len = 0; - for (t = &trace_types; *t; t = &(*t)->next) { - len = strlen((*t)->name); - if (len > max_tracer_type_len) - max_tracer_type_len = len; - } - out: +out: mutex_unlock(&trace_types_lock); } -void tracing_reset(struct trace_array *tr, int cpu) +static void __tracing_reset(struct trace_array *tr, int cpu) { ftrace_disable_cpu(); ring_buffer_reset_cpu(tr->buffer, cpu); ftrace_enable_cpu(); } +void tracing_reset(struct trace_array *tr, int cpu) +{ + struct ring_buffer *buffer = tr->buffer; + + ring_buffer_record_disable(buffer); + + /* Make sure all commits have finished */ + synchronize_sched(); + __tracing_reset(tr, cpu); + + ring_buffer_record_enable(buffer); +} + void tracing_reset_online_cpus(struct trace_array *tr) { + struct ring_buffer *buffer = tr->buffer; int cpu; + ring_buffer_record_disable(buffer); + + /* Make sure all commits have finished */ + synchronize_sched(); + tr->time_start = ftrace_now(tr->cpu); for_each_online_cpu(cpu) - tracing_reset(tr, cpu); + __tracing_reset(tr, cpu); + + ring_buffer_record_enable(buffer); } void tracing_reset_current(int cpu) @@ -682,8 +814,10 @@ static void trace_init_cmdlines(void) cmdline_idx = 0; } -static int trace_stop_count; -static DEFINE_SPINLOCK(tracing_start_lock); +int is_tracing_stopped(void) +{ + return trace_stop_count; +} /** * ftrace_off_permanent - disable all ftrace code permanently @@ -852,7 +986,7 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, entry->preempt_count = pc & 0xff; entry->pid = (tsk) ? tsk->pid : 0; - entry->tgid = (tsk) ? tsk->tgid : 0; + entry->lock_depth = (tsk) ? tsk->lock_depth : 0; entry->flags = #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | @@ -865,14 +999,15 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, } EXPORT_SYMBOL_GPL(tracing_generic_entry_update); -struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr, - int type, - unsigned long len, - unsigned long flags, int pc) +struct ring_buffer_event * +trace_buffer_lock_reserve(struct ring_buffer *buffer, + int type, + unsigned long len, + unsigned long flags, int pc) { struct ring_buffer_event *event; - event = ring_buffer_lock_reserve(tr->buffer, len); + event = ring_buffer_lock_reserve(buffer, len); if (event != NULL) { struct trace_entry *ent = ring_buffer_event_data(event); @@ -883,53 +1018,59 @@ struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr, return event; } -static inline void __trace_buffer_unlock_commit(struct trace_array *tr, - struct ring_buffer_event *event, - unsigned long flags, int pc, - int wake) +static inline void +__trace_buffer_unlock_commit(struct ring_buffer *buffer, + struct ring_buffer_event *event, + unsigned long flags, int pc, + int wake) { - ring_buffer_unlock_commit(tr->buffer, event); + ring_buffer_unlock_commit(buffer, event); - ftrace_trace_stack(tr, flags, 6, pc); - ftrace_trace_userstack(tr, flags, pc); + ftrace_trace_stack(buffer, flags, 6, pc); + ftrace_trace_userstack(buffer, flags, pc); if (wake) trace_wake_up(); } -void trace_buffer_unlock_commit(struct trace_array *tr, - struct ring_buffer_event *event, - unsigned long flags, int pc) +void trace_buffer_unlock_commit(struct ring_buffer *buffer, + struct ring_buffer_event *event, + unsigned long flags, int pc) { - __trace_buffer_unlock_commit(tr, event, flags, pc, 1); + __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); } struct ring_buffer_event * -trace_current_buffer_lock_reserve(int type, unsigned long len, +trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, + int type, unsigned long len, unsigned long flags, int pc) { - return trace_buffer_lock_reserve(&global_trace, + *current_rb = global_trace.buffer; + return trace_buffer_lock_reserve(*current_rb, type, len, flags, pc); } EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); -void trace_current_buffer_unlock_commit(struct ring_buffer_event *event, +void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, + struct ring_buffer_event *event, unsigned long flags, int pc) { - __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 1); + __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); } EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); -void trace_nowake_buffer_unlock_commit(struct ring_buffer_event *event, - unsigned long flags, int pc) +void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer, + struct ring_buffer_event *event, + unsigned long flags, int pc) { - __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 0); + __trace_buffer_unlock_commit(buffer, event, flags, pc, 0); } EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); -void trace_current_buffer_discard_commit(struct ring_buffer_event *event) +void trace_current_buffer_discard_commit(struct ring_buffer *buffer, + struct ring_buffer_event *event) { - ring_buffer_discard_commit(global_trace.buffer, event); + ring_buffer_discard_commit(buffer, event); } EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); @@ -939,6 +1080,7 @@ trace_function(struct trace_array *tr, int pc) { struct ftrace_event_call *call = &event_function; + struct ring_buffer *buffer = tr->buffer; struct ring_buffer_event *event; struct ftrace_entry *entry; @@ -946,7 +1088,7 @@ trace_function(struct trace_array *tr, if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) return; - event = trace_buffer_lock_reserve(tr, TRACE_FN, sizeof(*entry), + event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), flags, pc); if (!event) return; @@ -954,8 +1096,8 @@ trace_function(struct trace_array *tr, entry->ip = ip; entry->parent_ip = parent_ip; - if (!filter_check_discard(call, entry, tr->buffer, event)) - ring_buffer_unlock_commit(tr->buffer, event); + if (!filter_check_discard(call, entry, buffer, event)) + ring_buffer_unlock_commit(buffer, event); } void @@ -968,7 +1110,7 @@ ftrace(struct trace_array *tr, struct trace_array_cpu *data, } #ifdef CONFIG_STACKTRACE -static void __ftrace_trace_stack(struct trace_array *tr, +static void __ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, int skip, int pc) { @@ -977,7 +1119,7 @@ static void __ftrace_trace_stack(struct trace_array *tr, struct stack_entry *entry; struct stack_trace trace; - event = trace_buffer_lock_reserve(tr, TRACE_STACK, + event = trace_buffer_lock_reserve(buffer, TRACE_STACK, sizeof(*entry), flags, pc); if (!event) return; @@ -990,26 +1132,27 @@ static void __ftrace_trace_stack(struct trace_array *tr, trace.entries = entry->caller; save_stack_trace(&trace); - if (!filter_check_discard(call, entry, tr->buffer, event)) - ring_buffer_unlock_commit(tr->buffer, event); + if (!filter_check_discard(call, entry, buffer, event)) + ring_buffer_unlock_commit(buffer, event); } -void ftrace_trace_stack(struct trace_array *tr, unsigned long flags, int skip, - int pc) +void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, + int skip, int pc) { if (!(trace_flags & TRACE_ITER_STACKTRACE)) return; - __ftrace_trace_stack(tr, flags, skip, pc); + __ftrace_trace_stack(buffer, flags, skip, pc); } void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, int pc) { - __ftrace_trace_stack(tr, flags, skip, pc); + __ftrace_trace_stack(tr->buffer, flags, skip, pc); } -void ftrace_trace_userstack(struct trace_array *tr, unsigned long flags, int pc) +void +ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) { struct ftrace_event_call *call = &event_user_stack; struct ring_buffer_event *event; @@ -1019,12 +1162,13 @@ void ftrace_trace_userstack(struct trace_array *tr, unsigned long flags, int pc) if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) return; - event = trace_buffer_lock_reserve(tr, TRACE_USER_STACK, + event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, sizeof(*entry), flags, pc); if (!event) return; entry = ring_buffer_event_data(event); + entry->tgid = current->tgid; memset(&entry->caller, 0, sizeof(entry->caller)); trace.nr_entries = 0; @@ -1033,8 +1177,8 @@ void ftrace_trace_userstack(struct trace_array *tr, unsigned long flags, int pc) trace.entries = entry->caller; save_stack_trace_user(&trace); - if (!filter_check_discard(call, entry, tr->buffer, event)) - ring_buffer_unlock_commit(tr->buffer, event); + if (!filter_check_discard(call, entry, buffer, event)) + ring_buffer_unlock_commit(buffer, event); } #ifdef UNUSED @@ -1051,11 +1195,13 @@ ftrace_trace_special(void *__tr, unsigned long arg1, unsigned long arg2, unsigned long arg3, int pc) { + struct ftrace_event_call *call = &event_special; struct ring_buffer_event *event; struct trace_array *tr = __tr; + struct ring_buffer *buffer = tr->buffer; struct special_entry *entry; - event = trace_buffer_lock_reserve(tr, TRACE_SPECIAL, + event = trace_buffer_lock_reserve(buffer, TRACE_SPECIAL, sizeof(*entry), 0, pc); if (!event) return; @@ -1063,7 +1209,9 @@ ftrace_trace_special(void *__tr, entry->arg1 = arg1; entry->arg2 = arg2; entry->arg3 = arg3; - trace_buffer_unlock_commit(tr, event, 0, pc); + + if (!filter_check_discard(call, entry, buffer, event)) + trace_buffer_unlock_commit(buffer, event, 0, pc); } void @@ -1109,6 +1257,7 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) struct ftrace_event_call *call = &event_bprint; struct ring_buffer_event *event; + struct ring_buffer *buffer; struct trace_array *tr = &global_trace; struct trace_array_cpu *data; struct bprint_entry *entry; @@ -1141,7 +1290,9 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) goto out_unlock; size = sizeof(*entry) + sizeof(u32) * len; - event = trace_buffer_lock_reserve(tr, TRACE_BPRINT, size, flags, pc); + buffer = tr->buffer; + event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, + flags, pc); if (!event) goto out_unlock; entry = ring_buffer_event_data(event); @@ -1149,8 +1300,8 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) entry->fmt = fmt; memcpy(entry->buf, trace_buf, sizeof(u32) * len); - if (!filter_check_discard(call, entry, tr->buffer, event)) - ring_buffer_unlock_commit(tr->buffer, event); + if (!filter_check_discard(call, entry, buffer, event)) + ring_buffer_unlock_commit(buffer, event); out_unlock: __raw_spin_unlock(&trace_buf_lock); @@ -1165,14 +1316,30 @@ out: } EXPORT_SYMBOL_GPL(trace_vbprintk); -int trace_vprintk(unsigned long ip, const char *fmt, va_list args) +int trace_array_printk(struct trace_array *tr, + unsigned long ip, const char *fmt, ...) +{ + int ret; + va_list ap; + + if (!(trace_flags & TRACE_ITER_PRINTK)) + return 0; + + va_start(ap, fmt); + ret = trace_array_vprintk(tr, ip, fmt, ap); + va_end(ap); + return ret; +} + +int trace_array_vprintk(struct trace_array *tr, + unsigned long ip, const char *fmt, va_list args) { static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED; static char trace_buf[TRACE_BUF_SIZE]; struct ftrace_event_call *call = &event_print; struct ring_buffer_event *event; - struct trace_array *tr = &global_trace; + struct ring_buffer *buffer; struct trace_array_cpu *data; int cpu, len = 0, size, pc; struct print_entry *entry; @@ -1200,7 +1367,9 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args) trace_buf[len] = 0; size = sizeof(*entry) + len + 1; - event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc); + buffer = tr->buffer; + event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, + irq_flags, pc); if (!event) goto out_unlock; entry = ring_buffer_event_data(event); @@ -1208,8 +1377,8 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args) memcpy(&entry->buf, trace_buf, len); entry->buf[len] = 0; - if (!filter_check_discard(call, entry, tr->buffer, event)) - ring_buffer_unlock_commit(tr->buffer, event); + if (!filter_check_discard(call, entry, buffer, event)) + ring_buffer_unlock_commit(buffer, event); out_unlock: __raw_spin_unlock(&trace_buf_lock); @@ -1221,6 +1390,11 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args) return len; } + +int trace_vprintk(unsigned long ip, const char *fmt, va_list args) +{ + return trace_array_printk(&global_trace, ip, fmt, args); +} EXPORT_SYMBOL_GPL(trace_vprintk); enum trace_file_type { @@ -1360,6 +1534,37 @@ static void *s_next(struct seq_file *m, void *v, loff_t *pos) return ent; } +static void tracing_iter_reset(struct trace_iterator *iter, int cpu) +{ + struct trace_array *tr = iter->tr; + struct ring_buffer_event *event; + struct ring_buffer_iter *buf_iter; + unsigned long entries = 0; + u64 ts; + + tr->data[cpu]->skipped_entries = 0; + + if (!iter->buffer_iter[cpu]) + return; + + buf_iter = iter->buffer_iter[cpu]; + ring_buffer_iter_reset(buf_iter); + + /* + * We could have the case with the max latency tracers + * that a reset never took place on a cpu. This is evident + * by the timestamp being before the start of the buffer. + */ + while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { + if (ts >= iter->tr->time_start) + break; + entries++; + ring_buffer_read(buf_iter, NULL); + } + + tr->data[cpu]->skipped_entries = entries; +} + /* * No necessary locking here. The worst thing which can * happen is loosing events consumed at the same time @@ -1398,10 +1603,9 @@ static void *s_start(struct seq_file *m, loff_t *pos) if (cpu_file == TRACE_PIPE_ALL_CPU) { for_each_tracing_cpu(cpu) - ring_buffer_iter_reset(iter->buffer_iter[cpu]); + tracing_iter_reset(iter, cpu); } else - ring_buffer_iter_reset(iter->buffer_iter[cpu_file]); - + tracing_iter_reset(iter, cpu_file); ftrace_enable_cpu(); @@ -1430,10 +1634,10 @@ static void print_lat_help_header(struct seq_file *m) seq_puts(m, "# | / _----=> need-resched \n"); seq_puts(m, "# || / _---=> hardirq/softirq \n"); seq_puts(m, "# ||| / _--=> preempt-depth \n"); - seq_puts(m, "# |||| / \n"); - seq_puts(m, "# ||||| delay \n"); - seq_puts(m, "# cmd pid ||||| time | caller \n"); - seq_puts(m, "# \\ / ||||| \\ | / \n"); + seq_puts(m, "# |||| /_--=> lock-depth \n"); + seq_puts(m, "# |||||/ delay \n"); + seq_puts(m, "# cmd pid |||||| time | caller \n"); + seq_puts(m, "# \\ / |||||| \\ | / \n"); } static void print_func_help_header(struct seq_file *m) @@ -1450,16 +1654,32 @@ print_trace_header(struct seq_file *m, struct trace_iterator *iter) struct trace_array *tr = iter->tr; struct trace_array_cpu *data = tr->data[tr->cpu]; struct tracer *type = current_trace; - unsigned long total; - unsigned long entries; + unsigned long entries = 0; + unsigned long total = 0; + unsigned long count; const char *name = "preemption"; + int cpu; if (type) name = type->name; - entries = ring_buffer_entries(iter->tr->buffer); - total = entries + - ring_buffer_overruns(iter->tr->buffer); + + for_each_tracing_cpu(cpu) { + count = ring_buffer_entries_cpu(tr->buffer, cpu); + /* + * If this buffer has skipped entries, then we hold all + * entries for the trace and we need to ignore the + * ones before the time stamp. + */ + if (tr->data[cpu]->skipped_entries) { + count -= tr->data[cpu]->skipped_entries; + /* total is the same as the entries */ + total += count; + } else + total += count + + ring_buffer_overrun_cpu(tr->buffer, cpu); + entries += count; + } seq_printf(m, "# %s latency trace v1.1.5 on %s\n", name, UTS_RELEASE); @@ -1501,7 +1721,7 @@ print_trace_header(struct seq_file *m, struct trace_iterator *iter) seq_puts(m, "\n# => ended at: "); seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); trace_print_seq(m, &iter->seq); - seq_puts(m, "#\n"); + seq_puts(m, "\n#\n"); } seq_puts(m, "#\n"); @@ -1520,6 +1740,9 @@ static void test_cpu_buff_start(struct trace_iterator *iter) if (cpumask_test_cpu(iter->cpu, iter->started)) return; + if (iter->tr->data[iter->cpu]->skipped_entries) + return; + cpumask_set_cpu(iter->cpu, iter->started); /* Don't print started cpu buffer for the first entry of the trace */ @@ -1726,7 +1949,7 @@ static int s_show(struct seq_file *m, void *v) return 0; } -static struct seq_operations tracer_seq_ops = { +static const struct seq_operations tracer_seq_ops = { .start = s_start, .next = s_next, .stop = s_stop, @@ -1761,11 +1984,9 @@ __tracing_open(struct inode *inode, struct file *file) if (current_trace) *iter->trace = *current_trace; - if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) + if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) goto fail; - cpumask_clear(iter->started); - if (current_trace && current_trace->print_max) iter->tr = &max_tr; else @@ -1782,19 +2003,23 @@ __tracing_open(struct inode *inode, struct file *file) if (ring_buffer_overruns(iter->tr->buffer)) iter->iter_flags |= TRACE_FILE_ANNOTATE; + /* stop the trace while dumping */ + tracing_stop(); + if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { for_each_tracing_cpu(cpu) { iter->buffer_iter[cpu] = ring_buffer_read_start(iter->tr->buffer, cpu); + tracing_iter_reset(iter, cpu); } } else { cpu = iter->cpu_file; iter->buffer_iter[cpu] = ring_buffer_read_start(iter->tr->buffer, cpu); + tracing_iter_reset(iter, cpu); } - /* TODO stop tracer */ ret = seq_open(file, &tracer_seq_ops); if (ret < 0) { fail_ret = ERR_PTR(ret); @@ -1804,9 +2029,6 @@ __tracing_open(struct inode *inode, struct file *file) m = file->private_data; m->private = iter; - /* stop the trace while dumping */ - tracing_stop(); - mutex_unlock(&trace_types_lock); return iter; @@ -1817,6 +2039,7 @@ __tracing_open(struct inode *inode, struct file *file) ring_buffer_read_finish(iter->buffer_iter[cpu]); } free_cpumask_var(iter->started); + tracing_start(); fail: mutex_unlock(&trace_types_lock); kfree(iter->trace); @@ -1938,7 +2161,7 @@ static int t_show(struct seq_file *m, void *v) return 0; } -static struct seq_operations show_traces_seq_ops = { +static const struct seq_operations show_traces_seq_ops = { .start = t_start, .next = t_next, .stop = t_stop, @@ -2368,7 +2591,7 @@ static ssize_t tracing_set_trace_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { - char buf[max_tracer_type_len+2]; + char buf[MAX_TRACER_SIZE+2]; int r; mutex_lock(&trace_types_lock); @@ -2518,15 +2741,15 @@ static ssize_t tracing_set_trace_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { - char buf[max_tracer_type_len+1]; + char buf[MAX_TRACER_SIZE+1]; int i; size_t ret; int err; ret = cnt; - if (cnt > max_tracer_type_len) - cnt = max_tracer_type_len; + if (cnt > MAX_TRACER_SIZE) + cnt = MAX_TRACER_SIZE; if (copy_from_user(&buf, ubuf, cnt)) return -EFAULT; @@ -3780,17 +4003,9 @@ trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, if (ret < 0) return ret; - switch (val) { - case 0: - trace_flags &= ~(1 << index); - break; - case 1: - trace_flags |= 1 << index; - break; - - default: + if (val != 0 && val != 1) return -EINVAL; - } + set_tracer_flags(1 << index, val); *ppos += cnt; @@ -4172,7 +4387,7 @@ __init static int tracer_alloc_buffers(void) if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) goto out_free_buffer_mask; - if (!alloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL)) + if (!zalloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL)) goto out_free_tracing_cpumask; /* To save memory, keep the ring buffer size to its minimum */ @@ -4183,7 +4398,6 @@ __init static int tracer_alloc_buffers(void) cpumask_copy(tracing_buffer_mask, cpu_possible_mask); cpumask_copy(tracing_cpumask, cpu_all_mask); - cpumask_clear(tracing_reader_cpumask); /* TODO: make the number of buffers hot pluggable with CPUS */ global_trace.buffer = ring_buffer_alloc(ring_buf_size,