Re: [PATCH 4/5] tracing/core: drop the old ftrace_printk implementation in favour of ftrace_bprintk

From: Frédéric Weisbecker
Date: Mon Mar 02 2009 - 12:48:18 EST


2009/3/2 Steven Rostedt <rostedt@xxxxxxxxxxx>:
>
> On Sat, 28 Feb 2009, Frederic Weisbecker wrote:
>
>> Impact: faster and lighter tracing
>>
>> Now that we have ftrace_bprintk() which is faster and consume lesser
>> memory than ftrace_printk() and has the same purpose, we can now drop
>> the old implementation in favour of the binary one from ftrace_bprintk(),
>> which means we move all the implementation of ftrace_bprintk() to
>> ftrace_printk(), so the Api doesn't change except that we must now use
>> trace_seq_bprintk() to print the TRACE_PRINT entries.
>>
>> Some changes result of this:
>>
>> - Previously, ftrace_bprintk depended of a single tracer and couldn't
>>   work without. This tracer has been dropped and the whole implementation
>>   of ftrace_printk() (like the module formats management) is now integrated
>>   in the tracing core (comes with CONFIG_TRACING), though we keep the file
>>   trace_bprintk (previously trace_bprintk.c) where we can find the module
>
>    ^^^^^^^^^^^^^
>
>  Do you mean trace_printk.c ?

Exact :-)
I will resend a new iteration of this serie to address your reviews.

Thanks!


>
>>   management. Thus we don't overflow trace.c
>>
>> - changes some parts to use trace_seq_bprintk() to print TRACE_PRINT entries.
>>
>> - change a bit ftrace_printk/ftrace_vprintk macros to support non-builtin formats
>>   constants, and fix 'const' qualifiers warnings. But this is all transparent for
>>   developers.
>>
>> - etc...
>>
>> Signed-off-by: Frederic Weisbecker <fweisbec@xxxxxxxxx>
>> ---
>>  include/linux/ftrace.h                           |   68 ++++----
>>  include/linux/module.h                           |    2 +-
>>  kernel/trace/Kconfig                             |    7 +-
>>  kernel/trace/Makefile                            |    2 +-
>>  kernel/trace/trace.c                             |  209 +++++++---------------
>>  kernel/trace/trace.h                             |   14 +--
>>  kernel/trace/trace_functions_graph.c             |    6 +-
>>  kernel/trace/trace_mmiotrace.c                   |    9 +-
>>  kernel/trace/trace_output.c                      |   69 +------
>>  kernel/trace/trace_output.h                      |    2 +
>>  kernel/trace/{trace_bprintk.c => trace_printk.c} |  113 ++++--------
>>  11 files changed, 162 insertions(+), 339 deletions(-)
>>
>> diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
>> index f82b986..696a09b 100644
>> --- a/include/linux/ftrace.h
>> +++ b/include/linux/ftrace.h
>> @@ -222,31 +222,6 @@ extern int ftrace_make_nop(struct module *mod,
>>   */
>>  extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr);
>>
>> -#ifdef CONFIG_TRACE_BPRINTK
>> -extern int trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
>> -extern int __ftrace_bprintk(unsigned long ip, const char *fmt, ...)
>> -             __attribute__ ((format (printf, 2, 3)));
>> -
>> -static inline void  ____ftrace_bprintk_check_format(const char *fmt, ...)
>> -             __attribute__ ((format (printf, 1, 2)));
>> -static inline void ____ftrace_bprintk_check_format(const char *fmt, ...) {}
>> -#define __ftrace_bprintk_check_format(fmt, args...)                  \
>> -do {                                                                 \
>> -     if (0)                                                          \
>> -             ____ftrace_bprintk_check_format(fmt, ##args);           \
>> -} while (0)
>> -
>> -#define ftrace_bprintk(fmt, args...)                                 \
>> -do {                                                                 \
>> -     static char *__attribute__((section("__trace_bprintk_fmt")))    \
>> -                     ftrace_bprintk_fmt = fmt;                       \
>> -     __ftrace_bprintk_check_format(fmt, ##args);                     \
>> -     __ftrace_bprintk(_THIS_IP_, ftrace_bprintk_fmt, ##args);        \
>> -} while (0)
>> -#else
>> -#define ftrace_bprintk ftrace_printk
>> -#endif
>> -
>>  /* May be defined in arch */
>>  extern int ftrace_arch_read_dyn_info(char *buf, int size);
>>
>> @@ -367,15 +342,40 @@ ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3);
>>   * Please refrain from leaving ftrace_printks scattered around in
>>   * your code.
>>   */
>> -# define ftrace_printk(fmt...) __ftrace_printk(_THIS_IP_, fmt)
>> -extern int
>> -__ftrace_printk(unsigned long ip, const char *fmt, ...)
>> -     __attribute__ ((format (printf, 2, 3)));
>> -# define ftrace_vprintk(fmt, ap) __ftrace_printk(_THIS_IP_, fmt, ap)
>> -extern int
>> -__ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
>> +extern int __ftrace_vprintk(unsigned long ip, const char *fmt, va_list args);
>> +extern int __ftrace_printk(unsigned long ip, const char *fmt, ...)
>> +             __attribute__ ((format (printf, 2, 3)));
>> +
>> +static inline void  ____ftrace_printk_check_format(const char *fmt, ...)
>> +             __attribute__ ((format (printf, 1, 2)));
>> +static inline void ____ftrace_printk_check_format(const char *fmt, ...) {}
>> +#define __ftrace_printk_check_format(fmt, args...)                   \
>> +do {                                                                 \
>> +     if (0)                                                          \
>> +             ____ftrace_printk_check_format(fmt, ##args);            \
>> +} while (0)
>> +
>> +#define ftrace_vprintk(fmt, vargs)                                   \
>> +do {                                                                 \
>> +     static const char *ftrace_printk_fmt                            \
>> +     __attribute__((section("__trace_bprintk_fmt")));                \
>> +     ftrace_printk_fmt = fmt;                                        \
>> +     __ftrace_vprintk(_THIS_IP_, ftrace_printk_fmt, vargs);          \
>> +} while (0)
>> +
>> +#define ftrace_printk(fmt, args...)                                  \
>> +do {                                                                 \
>> +     static const char *ftrace_printk_fmt                            \
>> +     __attribute__((section("__trace_bprintk_fmt")));                \
>> +     ftrace_printk_fmt = fmt;                                        \
>> +     __ftrace_printk_check_format(fmt, ##args);                      \
>> +     __ftrace_printk(_THIS_IP_, ftrace_printk_fmt, ##args);          \
>> +} while (0)
>> +
>>  extern void ftrace_dump(void);
>> -#else
>> +
>> +#else /* !CONFIG_TRACING */
>> +
>>  static inline void
>>  ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) { }
>>  static inline int
>> @@ -395,7 +395,7 @@ ftrace_vprintk(const char *fmt, va_list ap)
>>       return 0;
>>  }
>>  static inline void ftrace_dump(void) { }
>> -#endif
>> +#endif /* CONFIG_TRACING */
>>
>>  #ifdef CONFIG_FTRACE_MCOUNT_RECORD
>>  extern void ftrace_init(void);
>> diff --git a/include/linux/module.h b/include/linux/module.h
>> index c4f2845..e418da1 100644
>> --- a/include/linux/module.h
>> +++ b/include/linux/module.h
>> @@ -347,7 +347,7 @@ struct module
>>       unsigned int num_tracepoints;
>>  #endif
>>
>> -#ifdef CONFIG_TRACE_BPRINTK
>> +#ifdef CONFIG_TRACING
>>       const char **trace_bprintk_fmt_start;
>>       unsigned int num_trace_bprintk_fmt;
>>  #endif
>> diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
>> index 2e84fc7..52439c8 100644
>> --- a/kernel/trace/Kconfig
>> +++ b/kernel/trace/Kconfig
>> @@ -52,6 +52,7 @@ config TRACING
>>       select STACKTRACE if STACKTRACE_SUPPORT
>>       select TRACEPOINTS
>>       select NOP_TRACER
>> +     select BINARY_PRINTF
>>
>>  menu "Tracers"
>>
>> @@ -86,12 +87,6 @@ config FUNCTION_GRAPH_TRACER
>>         This is done by setting the current return address on the current
>>         task structure into a stack of calls.
>>
>> -config TRACE_BPRINTK
>> -     bool "Binary printk for tracing"
>> -     default y
>> -     depends on TRACING
>> -     select BINARY_PRINTF
>> -
>>  config IRQSOFF_TRACER
>>       bool "Interrupts-off Latency Tracer"
>>       default n
>> diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
>> index dba6157..25e243f 100644
>> --- a/kernel/trace/Makefile
>> +++ b/kernel/trace/Makefile
>> @@ -22,7 +22,7 @@ obj-$(CONFIG_TRACING) += trace.o
>>  obj-$(CONFIG_TRACING) += trace_clock.o
>>  obj-$(CONFIG_TRACING) += trace_output.o
>>  obj-$(CONFIG_TRACING) += trace_stat.o
>> -obj-$(CONFIG_TRACE_BPRINTK) += trace_bprintk.o
>> +obj-$(CONFIG_TRACING) += trace_printk.o
>>  obj-$(CONFIG_CONTEXT_SWITCH_TRACER) += trace_sched_switch.o
>>  obj-$(CONFIG_SYSPROF_TRACER) += trace_sysprof.o
>>  obj-$(CONFIG_FUNCTION_TRACER) += trace_functions.o
>> diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
>> index 0e30dce..2ad285b 100644
>> --- a/kernel/trace/trace.c
>> +++ b/kernel/trace/trace.c
>> @@ -1171,6 +1171,67 @@ void trace_graph_return(struct ftrace_graph_ret *trace)
>>  }
>>  #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
>>
>> +
>> +/**
>> + * trace_vprintk - write binary msg to tracing buffer
>> + *
>> + * Caller must insure @fmt are valid when msg is in tracing buffer.
>> + */
>> +int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args)
>> +{
>> +     static DEFINE_SPINLOCK(trace_buf_lock);
>> +     static u32 trace_buf[TRACE_BUF_SIZE];
>> +
>> +     struct ring_buffer_event *event;
>> +     struct trace_array *tr = &global_trace;
>> +     struct trace_array_cpu *data;
>> +     struct print_entry *entry;
>> +     unsigned long flags;
>> +     int cpu, len = 0, size, pc;
>> +
>> +     if (unlikely(tracing_selftest_running || tracing_disabled))
>> +             return 0;
>> +
>> +     /* Don't pollute graph traces with trace_vprintk internals */
>> +     pause_graph_tracing();
>> +
>> +     pc = preempt_count();
>> +     preempt_disable_notrace();
>> +     cpu = raw_smp_processor_id();
>> +     data = tr->data[cpu];
>> +
>> +     if (unlikely(atomic_read(&data->disabled)))
>> +             goto out;
>> +
>> +     spin_lock_irqsave(&trace_buf_lock, flags);
>> +     len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args);
>> +
>> +     if (len > TRACE_BUF_SIZE || len < 0)
>> +             goto out_unlock;
>> +
>> +     size = sizeof(*entry) + sizeof(u32) * len;
>> +     event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, flags, pc);
>> +     if (!event)
>> +             goto out_unlock;
>> +     entry = ring_buffer_event_data(event);
>> +     entry->ip                       = ip;
>> +     entry->depth                    = depth;
>> +     entry->fmt                      = fmt;
>> +
>> +     memcpy(entry->buf, trace_buf, sizeof(u32) * len);
>> +     ring_buffer_unlock_commit(tr->buffer, event);
>> +
>> +out_unlock:
>> +     spin_unlock_irqrestore(&trace_buf_lock, flags);
>> +
>> +out:
>> +     preempt_enable_notrace();
>> +     unpause_graph_tracing();
>> +
>> +     return len;
>> +}
>> +EXPORT_SYMBOL_GPL(trace_vprintk);
>> +
>>  enum trace_file_type {
>>       TRACE_FILE_LAT_FMT      = 1,
>>       TRACE_FILE_ANNOTATE     = 2,
>> @@ -1588,7 +1649,7 @@ static enum print_line_t print_printk_msg_only(struct trace_iterator *iter)
>>
>>       trace_assign_type(field, entry);
>>
>> -     ret = trace_seq_printf(s, "%s", field->buf);
>> +     ret = trace_seq_bprintf(s, field->fmt, field->buf);
>>       if (!ret)
>>               return TRACE_TYPE_PARTIAL_LINE;
>>
>> @@ -3496,152 +3557,6 @@ static __init int tracer_init_debugfs(void)
>>       return 0;
>>  }
>>
>> -int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args)
>> -{
>> -     static DEFINE_SPINLOCK(trace_buf_lock);
>> -     static char trace_buf[TRACE_BUF_SIZE];
>> -
>> -     struct ring_buffer_event *event;
>> -     struct trace_array *tr = &global_trace;
>> -     struct trace_array_cpu *data;
>> -     int cpu, len = 0, size, pc;
>> -     struct print_entry *entry;
>> -     unsigned long irq_flags;
>> -
>> -     if (tracing_disabled || tracing_selftest_running)
>> -             return 0;
>> -
>> -     pc = preempt_count();
>> -     preempt_disable_notrace();
>> -     cpu = raw_smp_processor_id();
>> -     data = tr->data[cpu];
>> -
>> -     if (unlikely(atomic_read(&data->disabled)))
>> -             goto out;
>> -
>> -     pause_graph_tracing();
>> -     spin_lock_irqsave(&trace_buf_lock, irq_flags);
>> -     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;
>> -     event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc);
>> -     if (!event)
>> -             goto out_unlock;
>> -     entry = ring_buffer_event_data(event);
>> -     entry->ip                       = ip;
>> -     entry->depth                    = depth;
>> -
>> -     memcpy(&entry->buf, trace_buf, len);
>> -     entry->buf[len] = 0;
>> -     ring_buffer_unlock_commit(tr->buffer, event);
>> -
>> - out_unlock:
>> -     spin_unlock_irqrestore(&trace_buf_lock, irq_flags);
>> -     unpause_graph_tracing();
>> - out:
>> -     preempt_enable_notrace();
>> -
>> -     return len;
>> -}
>> -EXPORT_SYMBOL_GPL(trace_vprintk);
>> -
>> -int __ftrace_printk(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_vprintk(ip, task_curr_ret_stack(current), fmt, ap);
>> -     va_end(ap);
>> -     return ret;
>> -}
>> -EXPORT_SYMBOL_GPL(__ftrace_printk);
>> -
>> -int __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap)
>> -{
>> -     if (!(trace_flags & TRACE_ITER_PRINTK))
>> -             return 0;
>> -
>> -     return trace_vprintk(ip, task_curr_ret_stack(current), fmt, ap);
>> -}
>> -EXPORT_SYMBOL_GPL(__ftrace_vprintk);
>> -
>> -/**
>> - * trace_vbprintk - write binary msg to tracing buffer
>> - *
>> - * Caller must insure @fmt are valid when msg is in tracing buffer.
>> - */
>> -int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
>> -{
>> -     static DEFINE_SPINLOCK(trace_buf_lock);
>> -     static u32 trace_buf[TRACE_BUF_SIZE];
>> -
>> -     struct ring_buffer_event *event;
>> -     struct trace_array *tr = &global_trace;
>> -     struct trace_array_cpu *data;
>> -     struct bprintk_entry *entry;
>> -     unsigned long flags;
>> -     int cpu, len = 0, size, pc;
>> -
>> -     if (tracing_disabled || !trace_bprintk_enable)
>> -             return 0;
>> -
>> -     pc = preempt_count();
>> -     preempt_disable_notrace();
>> -     cpu = raw_smp_processor_id();
>> -     data = tr->data[cpu];
>> -
>> -     if (unlikely(atomic_read(&data->disabled)))
>> -             goto out;
>> -
>> -     spin_lock_irqsave(&trace_buf_lock, flags);
>> -     len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args);
>> -
>> -     if (len > TRACE_BUF_SIZE || len < 0)
>> -             goto out_unlock;
>> -
>> -     size = sizeof(*entry) + sizeof(u32) * len;
>> -     event = trace_buffer_lock_reserve(tr, TRACE_BPRINTK, size, flags, pc);
>> -     if (!event)
>> -             goto out_unlock;
>> -     entry = ring_buffer_event_data(event);
>> -     entry->ip                       = ip;
>> -     entry->fmt                      = fmt;
>> -
>> -     memcpy(entry->buf, trace_buf, sizeof(u32) * len);
>> -     ring_buffer_unlock_commit(tr->buffer, event);
>> -
>> -out_unlock:
>> -     spin_unlock_irqrestore(&trace_buf_lock, flags);
>> -
>> -out:
>> -     preempt_enable_notrace();
>> -
>> -     return len;
>> -}
>> -EXPORT_SYMBOL_GPL(trace_vbprintk);
>> -
>> -int __ftrace_bprintk(unsigned long ip, const char *fmt, ...)
>> -{
>> -     int ret;
>> -     va_list ap;
>> -
>> -     if (!fmt)
>> -             return 0;
>> -
>> -     va_start(ap, fmt);
>> -     ret = trace_vbprintk(ip, fmt, ap);
>> -     va_end(ap);
>> -     return ret;
>> -}
>> -EXPORT_SYMBOL_GPL(__ftrace_bprintk);
>> -
>>  static int trace_panic_handler(struct notifier_block *this,
>>                              unsigned long event, void *unused)
>>  {
>> diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
>> index 92703b1..0ccc678 100644
>> --- a/kernel/trace/trace.h
>> +++ b/kernel/trace/trace.h
>> @@ -20,7 +20,6 @@ enum trace_type {
>>       TRACE_WAKE,
>>       TRACE_STACK,
>>       TRACE_PRINT,
>> -     TRACE_BPRINTK,
>>       TRACE_SPECIAL,
>>       TRACE_MMIO_RW,
>>       TRACE_MMIO_MAP,
>> @@ -120,16 +119,10 @@ struct userstack_entry {
>>   */
>>  struct print_entry {
>>       struct trace_entry      ent;
>> -     unsigned long           ip;
>> +     unsigned long           ip;
>>       int                     depth;
>> -     char                    buf[];
>> -};
>> -
>> -struct bprintk_entry {
>> -     struct trace_entry ent;
>> -     unsigned long ip;
>> -     const char *fmt;
>> -     u32 buf[];
>> +     const char              *fmt;
>> +     u32                     buf[];
>>  };
>>  #ifdef CONFIG_TRACE_BPRINTK
>>  extern int trace_bprintk_enable;
>> @@ -295,7 +288,6 @@ extern void __ftrace_bad_type(void);
>>               IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK);   \
>>               IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
>>               IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);   \
>> -             IF_ASSIGN(var, ent, struct bprintk_entry, TRACE_BPRINTK);\
>>               IF_ASSIGN(var, ent, struct special_entry, 0);           \
>>               IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,          \
>>                         TRACE_MMIO_RW);                               \
>> diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
>> index 2461732..13e362d 100644
>> --- a/kernel/trace/trace_functions_graph.c
>> +++ b/kernel/trace/trace_functions_graph.c
>> @@ -742,7 +742,11 @@ print_graph_comment(struct print_entry *trace, struct trace_seq *s,
>>               }
>>
>>       /* The comment */
>> -     ret = trace_seq_printf(s, "/* %s", trace->buf);
>> +     ret = trace_seq_printf(s, "/* ");
>> +     if (!ret)
>> +             return TRACE_TYPE_PARTIAL_LINE;
>> +
>> +     ret = trace_seq_bprintf(s, trace->fmt, trace->buf);
>>       if (!ret)
>>               return TRACE_TYPE_PARTIAL_LINE;
>>
>> diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c
>> index c401b90..23e346a 100644
>> --- a/kernel/trace/trace_mmiotrace.c
>> +++ b/kernel/trace/trace_mmiotrace.c
>> @@ -254,15 +254,18 @@ static enum print_line_t mmio_print_mark(struct trace_iterator *iter)
>>  {
>>       struct trace_entry *entry = iter->ent;
>>       struct print_entry *print = (struct print_entry *)entry;
>> -     const char *msg         = print->buf;
>>       struct trace_seq *s     = &iter->seq;
>>       unsigned long long t    = ns2usecs(iter->ts);
>> -     unsigned long usec_rem  = do_div(t, 1000000ULL);
>> +     unsigned long usec_rem  = do_div(t, USEC_PER_SEC);
>>       unsigned secs           = (unsigned long)t;
>>       int ret;
>>
>>       /* The trailing newline must be in the message. */
>> -     ret = trace_seq_printf(s, "MARK %u.%06lu %s", secs, usec_rem, msg);
>> +     ret = trace_seq_printf(s, "MARK %u.%06lu ", secs, usec_rem);
>> +     if (!ret)
>> +             return TRACE_TYPE_PARTIAL_LINE;
>> +
>> +     ret = trace_seq_bprintf(s, print->fmt, print->buf);
>>       if (!ret)
>>               return TRACE_TYPE_PARTIAL_LINE;
>>
>> diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
>> index 7897b5d..a020a9b 100644
>> --- a/kernel/trace/trace_output.c
>> +++ b/kernel/trace/trace_output.c
>> @@ -53,8 +53,7 @@ trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
>>       return len;
>>  }
>>
>> -static int
>> -trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
>> +int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
>>  {
>>       int len = (PAGE_SIZE - 1) - s->len;
>>       int ret;
>> @@ -876,50 +875,6 @@ static enum print_line_t trace_print_print(struct trace_iterator *iter,
>>       if (!seq_print_ip_sym(s, field->ip, flags))
>>               goto partial;
>>
>> -     if (!trace_seq_printf(s, ": %s", field->buf))
>> -             goto partial;
>> -
>> -     return TRACE_TYPE_HANDLED;
>> -
>> - partial:
>> -     return TRACE_TYPE_PARTIAL_LINE;
>> -}
>> -
>> -static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags)
>> -{
>> -     struct print_entry *field;
>> -
>> -     trace_assign_type(field, iter->ent);
>> -
>> -     if (!trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf))
>> -             goto partial;
>> -
>> -     return TRACE_TYPE_HANDLED;
>> -
>> - partial:
>> -     return TRACE_TYPE_PARTIAL_LINE;
>> -}
>> -
>> -static struct trace_event trace_print_event = {
>> -     .type           = TRACE_PRINT,
>> -     .trace          = trace_print_print,
>> -     .latency_trace  = trace_print_print,
>> -     .raw            = trace_print_raw,
>> -};
>> -
>> -/* TRACE_BPRINTK */
>> -static enum print_line_t
>> -trace_bprintk_print(struct trace_iterator *iter, int flags)
>> -{
>> -     struct trace_entry *entry = iter->ent;
>> -     struct trace_seq *s = &iter->seq;
>> -     struct bprintk_entry *field;
>> -
>> -     trace_assign_type(field, entry);
>> -
>> -     if (!seq_print_ip_sym(s, field->ip, flags))
>> -             goto partial;
>> -
>>       if (!trace_seq_puts(s, ": "))
>>               goto partial;
>>
>> @@ -932,14 +887,13 @@ trace_bprintk_print(struct trace_iterator *iter, int flags)
>>       return TRACE_TYPE_PARTIAL_LINE;
>>  }
>>
>> -static enum print_line_t
>> -trace_bprintk_raw(struct trace_iterator *iter, int flags)
>> +
>> +static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags)
>>  {
>> -     struct trace_entry *entry = iter->ent;
>> +     struct print_entry *field;
>>       struct trace_seq *s = &iter->seq;
>> -     struct bprintk_entry *field;
>>
>> -     trace_assign_type(field, entry);
>> +     trace_assign_type(field, iter->ent);
>>
>>       if (!trace_seq_printf(s, ": %lx : ", field->ip))
>>               goto partial;
>> @@ -953,13 +907,11 @@ trace_bprintk_raw(struct trace_iterator *iter, int flags)
>>       return TRACE_TYPE_PARTIAL_LINE;
>>  }
>>
>> -static struct trace_event trace_bprintk_event = {
>> -     .type           = TRACE_BPRINTK,
>> -     .trace          = trace_bprintk_print,
>> -     .latency_trace  = trace_bprintk_print,
>> -     .raw            = trace_bprintk_raw,
>> -     .hex            = trace_nop_print,
>> -     .binary         = trace_nop_print,
>> +static struct trace_event trace_print_event = {
>> +     .type           = TRACE_PRINT,
>> +     .trace          = trace_print_print,
>> +     .latency_trace  = trace_print_print,
>> +     .raw            = trace_print_raw,
>>  };
>>
>>  static struct trace_event *events[] __initdata = {
>> @@ -970,7 +922,6 @@ static struct trace_event *events[] __initdata = {
>>       &trace_stack_event,
>>       &trace_user_stack_event,
>>       &trace_print_event,
>> -     &trace_bprintk_event,
>>       NULL
>>  };
>>
>> diff --git a/kernel/trace/trace_output.h b/kernel/trace/trace_output.h
>> index 551a25a..6d39010 100644
>> --- a/kernel/trace/trace_output.h
>> +++ b/kernel/trace/trace_output.h
>> @@ -19,6 +19,8 @@ struct trace_event {
>>  extern int trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
>>       __attribute__ ((format (printf, 2, 3)));
>>  extern int
>> +trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary);
>> +extern int
>>  seq_print_ip_sym(struct trace_seq *s, unsigned long ip,
>>               unsigned long sym_flags);
>>  extern ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf,
>> diff --git a/kernel/trace/trace_bprintk.c b/kernel/trace/trace_printk.c
>> similarity index 65%
>> rename from kernel/trace/trace_bprintk.c
>> rename to kernel/trace/trace_printk.c
>> index 28e6286..09f4ace 100644
>> --- a/kernel/trace/trace_bprintk.c
>> +++ b/kernel/trace/trace_printk.c
>> @@ -21,32 +21,21 @@
>>
>>  #ifdef CONFIG_MODULES
>>
>> -/* binary printk basic */
>> -static DEFINE_MUTEX(btrace_mutex);
>> -static int btrace_metadata_count;
>>  /*
>> - * modules ftrace_bprintk()'s formats are autosaved in struct trace_bprintk_fmt
>> + * modules ftrace_printk()'s formats are autosaved in struct trace_bprintk_fmt
>>   * which are queued on trace_bprintk_fmt_list.
>>   */
>>  static LIST_HEAD(trace_bprintk_fmt_list);
>>
>> +/* serialize accesses to trace_bprintk_fmt_list */
>> +static DEFINE_MUTEX(btrace_mutex);
>> +
>>  struct trace_bprintk_fmt {
>>       struct list_head list;
>>       int count;
>>       char fmt[0];
>>  };
>>
>> -
>> -static inline void lock_btrace(void)
>> -{
>> -     mutex_lock(&btrace_mutex);
>> -}
>> -
>> -static inline void unlock_btrace(void)
>> -{
>> -     mutex_unlock(&btrace_mutex);
>> -}
>> -
>
> Heh, OK, you removed it ;-)
>
> -- Steve
>
>>  /*
>>   * If trace_bprintk() is not active, we release the trace_bprintk's
>>   * formats that no modules has reference to.
>> @@ -76,7 +65,8 @@ static
>>  void hold_module_trace_bprintk_format(const char **start, const char **end)
>>  {
>>       const char **iter;
>> -     lock_btrace();
>> +
>> +     mutex_lock(&btrace_mutex);
>>       for (iter = start; iter < end; iter++) {
>>               struct trace_bprintk_fmt *tb_fmt = lookup_format(*iter);
>>               if (tb_fmt) {
>> @@ -95,14 +85,15 @@ void hold_module_trace_bprintk_format(const char **start, const char **end)
>>               } else
>>                       *iter = NULL;
>>       }
>> -     unlock_btrace();
>> +     mutex_unlock(&btrace_mutex);
>>  }
>>
>>  static
>>  void release_module_trace_bprintk_format(const char **start, const char **end)
>>  {
>>       const char **iter;
>> -     lock_btrace();
>> +
>> +     mutex_lock(&btrace_mutex);
>>       for (iter = start; iter < end; iter++) {
>>               struct trace_bprintk_fmt *tb_fmt;
>>               if (!*iter)
>> @@ -110,12 +101,12 @@ void release_module_trace_bprintk_format(const char **start, const char **end)
>>
>>               tb_fmt = container_of(*iter, struct trace_bprintk_fmt, fmt[0]);
>>               tb_fmt->count--;
>> -             if (!tb_fmt->count && !btrace_metadata_count) {
>> +             if (!tb_fmt->count) {
>>                       list_del(&tb_fmt->list);
>>                       kfree(tb_fmt);
>>               }
>>       }
>> -     unlock_btrace();
>> +     mutex_unlock(&btrace_mutex);
>>  }
>>
>>  static int module_trace_bprintk_format_notify(struct notifier_block *self,
>> @@ -134,24 +125,6 @@ static int module_trace_bprintk_format_notify(struct notifier_block *self,
>>       return 0;
>>  }
>>
>> -static void get_btrace_metadata(void)
>> -{
>> -     lock_btrace();
>> -     btrace_metadata_count++;
>> -     unlock_btrace();
>> -}
>> -
>> -static void put_btrace_metadata(void)
>> -{
>> -     lock_btrace();
>> -     btrace_metadata_count--;
>> -
>> -     if (!btrace_metadata_count) {
>> -             shrink_trace_bprintk_fmt();
>> -     }
>> -     unlock_btrace();
>> -}
>> -
>>  #else /* !CONFIG_MODULES */
>>  __init static int
>>  module_trace_bprintk_format_notify(struct notifier_block *self,
>> @@ -159,9 +132,6 @@ module_trace_bprintk_format_notify(struct notifier_block *self,
>>  {
>>       return 0;
>>  }
>> -
>> -static inline void get_btrace_metadata(void) { }
>> -static inline void put_btrace_metadata(void) { }
>>  #endif /* CONFIG_MODULES */
>>
>>
>> @@ -170,48 +140,39 @@ struct notifier_block module_trace_bprintk_format_nb = {
>>       .notifier_call = module_trace_bprintk_format_notify,
>>  };
>>
>> -/* events tracer */
>> -int trace_bprintk_enable;
>> -
>> -static void start_bprintk_trace(struct trace_array *tr)
>> +int __ftrace_printk(unsigned long ip, const char *fmt, ...)
>>  {
>> -     get_btrace_metadata();
>> -     tracing_reset_online_cpus(tr);
>> -     trace_bprintk_enable = 1;
>> -}
>> +     int ret;
>> +     va_list ap;
>>
>> -static void stop_bprintk_trace(struct trace_array *tr)
>> -{
>> -     trace_bprintk_enable = 0;
>> -     tracing_reset_online_cpus(tr);
>> -     put_btrace_metadata();
>> -}
>> +     if (unlikely(!fmt))
>> +             return 0;
>>
>> -static int init_bprintk_trace(struct trace_array *tr)
>> -{
>> -     start_bprintk_trace(tr);
>> -     return 0;
>> +     if (!(trace_flags & TRACE_ITER_PRINTK))
>> +             return 0;
>> +
>> +     va_start(ap, fmt);
>> +     ret = trace_vprintk(ip, task_curr_ret_stack(current), fmt, ap);
>> +     va_end(ap);
>> +     return ret;
>>  }
>> +EXPORT_SYMBOL_GPL(__ftrace_printk);
>>
>> -static struct tracer bprintk_trace __read_mostly =
>> +int __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap)
>>  {
>> -     .name        = "events",
>> -     .init        = init_bprintk_trace,
>> -     .reset       = stop_bprintk_trace,
>> -     .start       = start_bprintk_trace,
>> -     .stop        = stop_bprintk_trace,
>> -};
>> +     if (unlikely(!fmt))
>> +             return 0;
>>
>> -static __init int init_bprintk(void)
>> -{
>> -     int ret = register_module_notifier(&module_trace_bprintk_format_nb);
>> -     if (ret)
>> -             return ret;
>> +     if (!(trace_flags & TRACE_ITER_PRINTK))
>> +             return 0;
>>
>> -     ret = register_tracer(&bprintk_trace);
>> -     if (ret)
>> -             unregister_module_notifier(&module_trace_bprintk_format_nb);
>> -     return ret;
>> +     return trace_vprintk(ip, task_curr_ret_stack(current), fmt, ap);
>>  }
>> +EXPORT_SYMBOL_GPL(__ftrace_vprintk);
>> +
>>
>> -device_initcall(init_bprintk);
>> +static __init int init_trace_printk(void)
>> +{
>> +     return register_module_notifier(&module_trace_bprintk_format_nb);
>> +}
>> +early_initcall(init_trace_printk);
>> --
>> 1.6.1
>>
>>
>>
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/