diff options
Diffstat (limited to 'kernel/trace/trace.c')
-rw-r--r-- | kernel/trace/trace.c | 307 |
1 files changed, 159 insertions, 148 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 874f289..8b9f20a 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -12,7 +12,7 @@ * Copyright (C) 2004 William Lee Irwin III */ #include <linux/ring_buffer.h> -#include <linux/utsrelease.h> +#include <generated/utsrelease.h> #include <linux/stacktrace.h> #include <linux/writeback.h> #include <linux/kallsyms.h> @@ -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(); } @@ -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; @@ -313,7 +313,6 @@ static const char *trace_options[] = { "bin", "block", "stacktrace", - "sched-tree", "trace_printk", "ftrace_preempt", "branch", @@ -493,15 +492,15 @@ static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) * protected by per_cpu spinlocks. But the action of the swap * needs its own lock. * - * This is defined as a raw_spinlock_t in order to help + * This is defined as a arch_spinlock_t in order to help * with performance when lockdep debugging is enabled. * * It is also used in other places outside the update_max_tr * so it needs to be defined outside of the * CONFIG_TRACER_MAX_TRACE. */ -static raw_spinlock_t ftrace_max_lock = - (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; +static arch_spinlock_t ftrace_max_lock = + (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; #ifdef CONFIG_TRACER_MAX_TRACE unsigned long __read_mostly tracing_max_latency; @@ -555,13 +554,13 @@ update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) return; WARN_ON_ONCE(!irqs_disabled()); - __raw_spin_lock(&ftrace_max_lock); + arch_spin_lock(&ftrace_max_lock); tr->buffer = max_tr.buffer; max_tr.buffer = buf; __update_max_tr(tr, tsk, cpu); - __raw_spin_unlock(&ftrace_max_lock); + arch_spin_unlock(&ftrace_max_lock); } /** @@ -581,7 +580,7 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) return; WARN_ON_ONCE(!irqs_disabled()); - __raw_spin_lock(&ftrace_max_lock); + arch_spin_lock(&ftrace_max_lock); ftrace_disable_cpu(); @@ -603,7 +602,7 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); __update_max_tr(tr, tsk, cpu); - __raw_spin_unlock(&ftrace_max_lock); + arch_spin_unlock(&ftrace_max_lock); } #endif /* CONFIG_TRACER_MAX_TRACE */ @@ -802,7 +801,7 @@ static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; static int cmdline_idx; -static raw_spinlock_t trace_cmdline_lock = __RAW_SPIN_LOCK_UNLOCKED; +static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; /* temporary disable recording */ static atomic_t trace_record_cmdline_disabled __read_mostly; @@ -915,7 +914,7 @@ static void trace_save_cmdline(struct task_struct *tsk) * nor do we want to disable interrupts, * so if we miss here, then better luck next time. */ - if (!__raw_spin_trylock(&trace_cmdline_lock)) + if (!arch_spin_trylock(&trace_cmdline_lock)) return; idx = map_pid_to_cmdline[tsk->pid]; @@ -940,7 +939,7 @@ static void trace_save_cmdline(struct task_struct *tsk) memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); - __raw_spin_unlock(&trace_cmdline_lock); + arch_spin_unlock(&trace_cmdline_lock); } void trace_find_cmdline(int pid, char comm[]) @@ -958,14 +957,14 @@ void trace_find_cmdline(int pid, char comm[]) } preempt_disable(); - __raw_spin_lock(&trace_cmdline_lock); + arch_spin_lock(&trace_cmdline_lock); map = map_pid_to_cmdline[pid]; if (map != NO_CMDLINE_MAP) strcpy(comm, saved_cmdlines[map]); else strcpy(comm, "<...>"); - __raw_spin_unlock(&trace_cmdline_lock); + arch_spin_unlock(&trace_cmdline_lock); preempt_enable(); } @@ -1085,7 +1084,7 @@ 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), @@ -1151,6 +1150,22 @@ void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, __ftrace_trace_stack(tr->buffer, flags, skip, pc); } +/** + * trace_dump_stack - record a stack back trace in the trace buffer + */ +void trace_dump_stack(void) +{ + unsigned long flags; + + if (tracing_disabled || tracing_selftest_running) + return; + + local_save_flags(flags); + + /* skipping 3 traces, seems to get us at the caller of this function */ + __ftrace_trace_stack(global_trace.buffer, flags, 3, preempt_count()); +} + void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) { @@ -1251,8 +1266,8 @@ ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) */ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) { - static raw_spinlock_t trace_buf_lock = - (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; + static arch_spinlock_t trace_buf_lock = + (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; static u32 trace_buf[TRACE_BUF_SIZE]; struct ftrace_event_call *call = &event_bprint; @@ -1283,7 +1298,7 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) /* Lockdep uses trace_printk for lock tracing */ local_irq_save(flags); - __raw_spin_lock(&trace_buf_lock); + arch_spin_lock(&trace_buf_lock); len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args); if (len > TRACE_BUF_SIZE || len < 0) @@ -1304,7 +1319,7 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) ring_buffer_unlock_commit(buffer, event); out_unlock: - __raw_spin_unlock(&trace_buf_lock); + arch_spin_unlock(&trace_buf_lock); local_irq_restore(flags); out: @@ -1334,7 +1349,7 @@ int trace_array_printk(struct trace_array *tr, 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 arch_spinlock_t trace_buf_lock = __ARCH_SPIN_LOCK_UNLOCKED; static char trace_buf[TRACE_BUF_SIZE]; struct ftrace_event_call *call = &event_print; @@ -1360,12 +1375,8 @@ int trace_array_vprintk(struct trace_array *tr, pause_graph_tracing(); raw_local_irq_save(irq_flags); - __raw_spin_lock(&trace_buf_lock); - if (args == NULL) { - strncpy(trace_buf, fmt, TRACE_BUF_SIZE); - len = strlen(trace_buf); - } else - len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); + arch_spin_lock(&trace_buf_lock); + len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); size = sizeof(*entry) + len + 1; buffer = tr->buffer; @@ -1382,7 +1393,7 @@ int trace_array_vprintk(struct trace_array *tr, ring_buffer_unlock_commit(buffer, event); out_unlock: - __raw_spin_unlock(&trace_buf_lock); + arch_spin_unlock(&trace_buf_lock); raw_local_irq_restore(irq_flags); unpause_graph_tracing(); out: @@ -1516,6 +1527,8 @@ 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 */ @@ -1614,8 +1627,16 @@ 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(); @@ -1923,6 +1944,7 @@ 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) { @@ -1942,9 +1964,27 @@ 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; @@ -2254,7 +2294,7 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf, mutex_lock(&tracing_cpumask_update_lock); local_irq_disable(); - __raw_spin_lock(&ftrace_max_lock); + arch_spin_lock(&ftrace_max_lock); for_each_tracing_cpu(cpu) { /* * Increase/decrease the disabled counter if we are @@ -2269,7 +2309,7 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf, atomic_dec(&global_trace.data[cpu]->disabled); } } - __raw_spin_unlock(&ftrace_max_lock); + arch_spin_unlock(&ftrace_max_lock); local_irq_enable(); cpumask_copy(tracing_cpumask, tracing_cpumask_new); @@ -2291,67 +2331,49 @@ static const struct file_operations tracing_cpumask_fops = { .write = tracing_cpumask_write, }; -static ssize_t -tracing_trace_options_read(struct file *filp, char __user *ubuf, - size_t cnt, loff_t *ppos) +static int tracing_trace_options_show(struct seq_file *m, void *v) { struct tracer_opt *trace_opts; u32 tracer_flags; - int len = 0; - char *buf; - int r = 0; int i; - - /* calculate max size */ - for (i = 0; trace_options[i]; i++) { - len += strlen(trace_options[i]); - len += 3; /* "no" and newline */ - } - mutex_lock(&trace_types_lock); tracer_flags = current_trace->flags->val; trace_opts = current_trace->flags->opts; - /* - * Increase the size with names of options specific - * of the current tracer. - */ - for (i = 0; trace_opts[i].name; i++) { - len += strlen(trace_opts[i].name); - len += 3; /* "no" and newline */ - } - - /* +1 for \0 */ - buf = kmalloc(len + 1, GFP_KERNEL); - if (!buf) { - mutex_unlock(&trace_types_lock); - return -ENOMEM; - } - for (i = 0; trace_options[i]; i++) { if (trace_flags & (1 << i)) - r += sprintf(buf + r, "%s\n", trace_options[i]); + seq_printf(m, "%s\n", trace_options[i]); else - r += sprintf(buf + r, "no%s\n", trace_options[i]); + seq_printf(m, "no%s\n", trace_options[i]); } for (i = 0; trace_opts[i].name; i++) { if (tracer_flags & trace_opts[i].bit) - r += sprintf(buf + r, "%s\n", - trace_opts[i].name); + seq_printf(m, "%s\n", trace_opts[i].name); else - r += sprintf(buf + r, "no%s\n", - trace_opts[i].name); + seq_printf(m, "no%s\n", trace_opts[i].name); } mutex_unlock(&trace_types_lock); - WARN_ON(r >= len + 1); + return 0; +} - r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); +static int __set_tracer_option(struct tracer *trace, + struct tracer_flags *tracer_flags, + struct tracer_opt *opts, int neg) +{ + int ret; - kfree(buf); - return r; + ret = trace->set_flag(tracer_flags->val, opts->bit, !neg); + if (ret) + return ret; + + if (neg) + tracer_flags->val &= ~opts->bit; + else + tracer_flags->val |= opts->bit; + return 0; } /* Try to assign a tracer specific option */ @@ -2359,33 +2381,17 @@ static int set_tracer_option(struct tracer *trace, char *cmp, int neg) { struct tracer_flags *tracer_flags = trace->flags; struct tracer_opt *opts = NULL; - int ret = 0, i = 0; - int len; + int i; for (i = 0; tracer_flags->opts[i].name; i++) { opts = &tracer_flags->opts[i]; - len = strlen(opts->name); - if (strncmp(cmp, opts->name, len) == 0) { - ret = trace->set_flag(tracer_flags->val, - opts->bit, !neg); - break; - } + if (strcmp(cmp, opts->name) == 0) + return __set_tracer_option(trace, trace->flags, + opts, neg); } - /* Not found */ - if (!tracer_flags->opts[i].name) - return -EINVAL; - - /* Refused to handle */ - if (ret) - return ret; - - if (neg) - tracer_flags->val &= ~opts->bit; - else - tracer_flags->val |= opts->bit; - return 0; + return -EINVAL; } static void set_tracer_flags(unsigned int mask, int enabled) @@ -2405,7 +2411,7 @@ tracing_trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { char buf[64]; - char *cmp = buf; + char *cmp; int neg = 0; int ret; int i; @@ -2417,16 +2423,15 @@ tracing_trace_options_write(struct file *filp, const char __user *ubuf, return -EFAULT; buf[cnt] = 0; + cmp = strstrip(buf); - if (strncmp(buf, "no", 2) == 0) { + if (strncmp(cmp, "no", 2) == 0) { neg = 1; cmp += 2; } for (i = 0; trace_options[i]; i++) { - int len = strlen(trace_options[i]); - - if (strncmp(cmp, trace_options[i], len) == 0) { + if (strcmp(cmp, trace_options[i]) == 0) { set_tracer_flags(1 << i, !neg); break; } @@ -2446,9 +2451,18 @@ tracing_trace_options_write(struct file *filp, const char __user *ubuf, return cnt; } +static int tracing_trace_options_open(struct inode *inode, struct file *file) +{ + if (tracing_disabled) + return -ENODEV; + return single_open(file, tracing_trace_options_show, NULL); +} + static const struct file_operations tracing_iter_fops = { - .open = tracing_open_generic, - .read = tracing_trace_options_read, + .open = tracing_trace_options_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, .write = tracing_trace_options_write, }; @@ -2898,6 +2912,10 @@ 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); @@ -3104,7 +3122,7 @@ static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, __free_page(spd->pages[idx]); } -static struct pipe_buf_operations tracing_pipe_buf_ops = { +static const struct pipe_buf_operations tracing_pipe_buf_ops = { .can_merge = 0, .map = generic_pipe_buf_map, .unmap = generic_pipe_buf_unmap, @@ -3320,6 +3338,16 @@ tracing_entries_write(struct file *filp, const char __user *ubuf, return cnt; } +static int mark_printk(const char *fmt, ...) +{ + int ret; + va_list args; + va_start(args, fmt); + ret = trace_vprintk(0, fmt, args); + va_end(args); + return ret; +} + static ssize_t tracing_mark_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *fpos) @@ -3346,28 +3374,25 @@ tracing_mark_write(struct file *filp, const char __user *ubuf, } else buf[cnt] = '\0'; - cnt = trace_vprintk(0, buf, NULL); + cnt = mark_printk("%s", buf); kfree(buf); *fpos += cnt; return cnt; } -static ssize_t tracing_clock_read(struct file *filp, char __user *ubuf, - size_t cnt, loff_t *ppos) +static int tracing_clock_show(struct seq_file *m, void *v) { - char buf[64]; - int bufiter = 0; int i; for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) - bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, + seq_printf(m, "%s%s%s%s", i ? " " : "", i == trace_clock_id ? "[" : "", trace_clocks[i].name, i == trace_clock_id ? "]" : ""); - bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, "\n"); + seq_putc(m, '\n'); - return simple_read_from_buffer(ubuf, cnt, ppos, buf, bufiter); + return 0; } static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, @@ -3409,6 +3434,13 @@ static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, return cnt; } +static int tracing_clock_open(struct inode *inode, struct file *file) +{ + if (tracing_disabled) + return -ENODEV; + return single_open(file, tracing_clock_show, NULL); +} + static const struct file_operations tracing_max_lat_fops = { .open = tracing_open_generic, .read = tracing_max_lat_read, @@ -3447,8 +3479,10 @@ static const struct file_operations tracing_mark_fops = { }; static const struct file_operations trace_clock_fops = { - .open = tracing_open_generic, - .read = tracing_clock_read, + .open = tracing_clock_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, .write = tracing_clock_write, }; @@ -3578,7 +3612,7 @@ static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, } /* Pipe buffer operations for a buffer. */ -static struct pipe_buf_operations buffer_pipe_buf_ops = { +static const struct pipe_buf_operations buffer_pipe_buf_ops = { .can_merge = 0, .map = generic_pipe_buf_map, .unmap = generic_pipe_buf_unmap, @@ -3909,39 +3943,16 @@ trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, if (ret < 0) return ret; - ret = 0; - switch (val) { - case 0: - /* do nothing if already cleared */ - if (!(topt->flags->val & topt->opt->bit)) - break; - - mutex_lock(&trace_types_lock); - if (current_trace->set_flag) - ret = current_trace->set_flag(topt->flags->val, - topt->opt->bit, 0); - mutex_unlock(&trace_types_lock); - if (ret) - return ret; - topt->flags->val &= ~topt->opt->bit; - break; - case 1: - /* do nothing if already set */ - if (topt->flags->val & topt->opt->bit) - break; + if (val != 0 && val != 1) + return -EINVAL; + if (!!(topt->flags->val & topt->opt->bit) != val) { mutex_lock(&trace_types_lock); - if (current_trace->set_flag) - ret = current_trace->set_flag(topt->flags->val, - topt->opt->bit, 1); + ret = __set_tracer_option(current_trace, topt->flags, + topt->opt, val); mutex_unlock(&trace_types_lock); if (ret) return ret; - topt->flags->val |= topt->opt->bit; - break; - - default: - return -EINVAL; } *ppos += cnt; @@ -4268,8 +4279,8 @@ trace_printk_seq(struct trace_seq *s) static void __ftrace_dump(bool disable_tracing) { - static raw_spinlock_t ftrace_dump_lock = - (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; + static arch_spinlock_t ftrace_dump_lock = + (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; /* use static because iter can be a bit big for the stack */ static struct trace_iterator iter; unsigned int old_userobj; @@ -4279,7 +4290,7 @@ static void __ftrace_dump(bool disable_tracing) /* only one dump */ local_irq_save(flags); - __raw_spin_lock(&ftrace_dump_lock); + arch_spin_lock(&ftrace_dump_lock); if (dump_ran) goto out; @@ -4354,7 +4365,7 @@ static void __ftrace_dump(bool disable_tracing) } out: - __raw_spin_unlock(&ftrace_dump_lock); + arch_spin_unlock(&ftrace_dump_lock); local_irq_restore(flags); } @@ -4415,7 +4426,7 @@ __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(); |