diff options
Diffstat (limited to 'kernel/trace/trace.c')
-rw-r--r-- | kernel/trace/trace.c | 80 |
1 files changed, 54 insertions, 26 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index b20d3ec75de9..c82dfd92fdfd 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -86,17 +86,17 @@ static int dummy_set_flag(u32 old_flags, u32 bit, int set) */ static int tracing_disabled = 1; -DEFINE_PER_CPU(local_t, ftrace_cpu_disabled); +DEFINE_PER_CPU(int, ftrace_cpu_disabled); static inline void ftrace_disable_cpu(void) { preempt_disable(); - local_inc(&__get_cpu_var(ftrace_cpu_disabled)); + __this_cpu_inc(per_cpu_var(ftrace_cpu_disabled)); } static inline void ftrace_enable_cpu(void) { - local_dec(&__get_cpu_var(ftrace_cpu_disabled)); + __this_cpu_dec(per_cpu_var(ftrace_cpu_disabled)); preempt_enable(); } @@ -129,7 +129,7 @@ static int tracing_set_tracer(const char *buf); static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; static char *default_bootup_tracer; -static int __init set_ftrace(char *str) +static int __init set_cmdline_ftrace(char *str) { strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); default_bootup_tracer = bootup_tracer_buf; @@ -137,7 +137,7 @@ static int __init set_ftrace(char *str) ring_buffer_expanded = 1; return 1; } -__setup("ftrace=", set_ftrace); +__setup("ftrace=", set_cmdline_ftrace); static int __init set_ftrace_dump_on_oops(char *str) { @@ -203,7 +203,7 @@ cycle_t ftrace_now(int cpu) */ static struct trace_array max_tr; -static DEFINE_PER_CPU(struct trace_array_cpu, max_data); +static DEFINE_PER_CPU(struct trace_array_cpu, max_tr_data); /* tracer_enabled is used to toggle activation of a tracer */ static int tracer_enabled = 1; @@ -1085,7 +1085,7 @@ trace_function(struct trace_array *tr, struct ftrace_entry *entry; /* If we are reading the ring buffer, don't trace */ - if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) + if (unlikely(__this_cpu_read(per_cpu_var(ftrace_cpu_disabled)))) return; event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), @@ -1363,9 +1363,6 @@ int trace_array_vprintk(struct trace_array *tr, __raw_spin_lock(&trace_buf_lock); len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); - len = min(len, TRACE_BUF_SIZE-1); - trace_buf[len] = 0; - size = sizeof(*entry) + len + 1; buffer = tr->buffer; event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, @@ -1373,10 +1370,10 @@ int trace_array_vprintk(struct trace_array *tr, if (!event) goto out_unlock; entry = ring_buffer_event_data(event); - entry->ip = ip; + entry->ip = ip; memcpy(&entry->buf, trace_buf, len); - entry->buf[len] = 0; + entry->buf[len] = '\0'; if (!filter_check_discard(call, entry, buffer, event)) ring_buffer_unlock_commit(buffer, event); @@ -1515,6 +1512,8 @@ static void *s_next(struct seq_file *m, void *v, loff_t *pos) int i = (int)*pos; void *ent; + WARN_ON_ONCE(iter->leftover); + (*pos)++; /* can't go backwards */ @@ -1613,8 +1612,16 @@ static void *s_start(struct seq_file *m, loff_t *pos) ; } else { - l = *pos - 1; - p = s_next(m, p, &l); + /* + * If we overflowed the seq_file before, then we want + * to just reuse the trace_seq buffer again. + */ + if (iter->leftover) + p = iter; + else { + l = *pos - 1; + p = s_next(m, p, &l); + } } trace_event_read_lock(); @@ -1922,6 +1929,7 @@ static enum print_line_t print_trace_line(struct trace_iterator *iter) static int s_show(struct seq_file *m, void *v) { struct trace_iterator *iter = v; + int ret; if (iter->ent == NULL) { if (iter->tr) { @@ -1941,9 +1949,27 @@ static int s_show(struct seq_file *m, void *v) if (!(trace_flags & TRACE_ITER_VERBOSE)) print_func_help_header(m); } + } else if (iter->leftover) { + /* + * If we filled the seq_file buffer earlier, we + * want to just show it now. + */ + ret = trace_print_seq(m, &iter->seq); + + /* ret should this time be zero, but you never know */ + iter->leftover = ret; + } else { print_trace_line(iter); - trace_print_seq(m, &iter->seq); + ret = trace_print_seq(m, &iter->seq); + /* + * If we overflow the seq_file buffer, then it will + * ask us for this data again at start up. + * Use that instead. + * ret is 0 if seq_file write succeeded. + * -1 otherwise. + */ + iter->leftover = ret; } return 0; @@ -2897,6 +2923,10 @@ static int tracing_release_pipe(struct inode *inode, struct file *file) else cpumask_clear_cpu(iter->cpu_file, tracing_reader_cpumask); + + if (iter->trace->pipe_close) + iter->trace->pipe_close(iter); + mutex_unlock(&trace_types_lock); free_cpumask_var(iter->started); @@ -3334,7 +3364,6 @@ tracing_mark_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *fpos) { char *buf; - char *end; if (tracing_disabled) return -EINVAL; @@ -3342,7 +3371,7 @@ tracing_mark_write(struct file *filp, const char __user *ubuf, if (cnt > TRACE_BUF_SIZE) cnt = TRACE_BUF_SIZE; - buf = kmalloc(cnt + 1, GFP_KERNEL); + buf = kmalloc(cnt + 2, GFP_KERNEL); if (buf == NULL) return -ENOMEM; @@ -3350,14 +3379,13 @@ tracing_mark_write(struct file *filp, const char __user *ubuf, kfree(buf); return -EFAULT; } + if (buf[cnt-1] != '\n') { + buf[cnt] = '\n'; + buf[cnt+1] = '\0'; + } else + buf[cnt] = '\0'; - /* Cut from the first nil or newline. */ - buf[cnt] = '\0'; - end = strchr(buf, '\n'); - if (end) - *end = '\0'; - - cnt = mark_printk("%s\n", buf); + cnt = mark_printk("%s", buf); kfree(buf); *fpos += cnt; @@ -3730,7 +3758,7 @@ tracing_stats_read(struct file *filp, char __user *ubuf, s = kmalloc(sizeof(*s), GFP_KERNEL); if (!s) - return ENOMEM; + return -ENOMEM; trace_seq_init(s); @@ -4426,7 +4454,7 @@ __init static int tracer_alloc_buffers(void) /* Allocate the first page for all buffers */ for_each_tracing_cpu(i) { global_trace.data[i] = &per_cpu(global_trace_cpu, i); - max_tr.data[i] = &per_cpu(max_data, i); + max_tr.data[i] = &per_cpu(max_tr_data, i); } trace_init_cmdlines(); |