Re: [PATCH tip 2/2] tracing: Introducetrace_buffer_{lock_reserve,unlock_commit}

From: Frederic Weisbecker
Date: Thu Feb 05 2009 - 17:59:41 EST


On Thu, Feb 05, 2009 at 04:14:13PM -0200, Arnaldo Carvalho de Melo wrote:
> Impact: new API
>
> These new functions do what previously was being open coded, reducing
> the number of details ftrace plugin writers have to worry about.
>
> It also standardizes the handling of stacktrace, userstacktrace and
> other trace options we may introduce in the future.
>
> With this patch, for instance, the blk tracer (and some others already
> in the tree) can use the "userstacktrace" /d/tracing/trace_options
> facility.
>
> Cc: Ingo Molnar <mingo@xxxxxxx>
> Cc: Frédéric Weisbecker <fweisbec@xxxxxxxxx>
> Cc: Jens Axboe <jens.axboe@xxxxxxxxxx>
> Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
> ---
> block/blktrace.c | 21 ++------
> kernel/trace/kmemtrace.c | 19 ++-----
> kernel/trace/trace.c | 94 +++++++++++++++++++++----------------
> kernel/trace/trace.h | 11 ++++
> kernel/trace/trace_boot.c | 20 ++------
> kernel/trace/trace_branch.c | 7 +--
> kernel/trace/trace_hw_branches.c | 7 +--
> kernel/trace/trace_mmiotrace.c | 20 +++-----
> kernel/trace/trace_power.c | 20 ++------
> 9 files changed, 102 insertions(+), 117 deletions(-)
>
> $ codiff /tmp/vmlinux.before /tmp/vmlinux.after
> linux-2.6-tip/kernel/trace/trace.c:
> trace_vprintk | -5
> trace_graph_return | -22
> trace_graph_entry | -26
> trace_function | -45
> __ftrace_trace_stack | -27
> ftrace_trace_userstack | -29
> tracing_sched_switch_trace | -66
> tracing_stop | +1
> trace_seq_to_user | -1
> ftrace_trace_special | -63
> ftrace_special | +1
> tracing_sched_wakeup_trace | -70
> tracing_reset_online_cpus | -1
> 13 functions changed, 2 bytes added, 355 bytes removed, diff: -353
>
> linux-2.6-tip/block/blktrace.c:
> __blk_add_trace | -58
> 1 function changed, 58 bytes removed, diff: -58
>
> linux-2.6-tip/kernel/trace/trace.c:
> trace_buffer_lock_reserve | +88
> trace_buffer_unlock_commit | +86
> 2 functions changed, 174 bytes added, diff: +174
>
> /tmp/vmlinux.after:
> 16 functions changed, 176 bytes added, 413 bytes removed, diff: -237
>
> diff --git a/block/blktrace.c b/block/blktrace.c
> index 8e52f24..834cd84 100644
> --- a/block/blktrace.c
> +++ b/block/blktrace.c
> @@ -187,19 +187,15 @@ static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes,
> cpu = raw_smp_processor_id();
>
> if (blk_tr) {
> - struct trace_entry *ent;
> tracing_record_cmdline(current);
>
> - event = ring_buffer_lock_reserve(blk_tr->buffer,
> - sizeof(*t) + pdu_len);
> + pc = preempt_count();
> + event = trace_buffer_lock_reserve(blk_tr, TRACE_BLK,
> + sizeof(*t) + pdu_len,
> + 0, pc);

Oh that's a good idea. That makes it more simple and abstract more the ring buffer
from tracing.

> if (!event)
> return;
> -
> - ent = ring_buffer_event_data(event);
> - t = (struct blk_io_trace *)ent;
> - pc = preempt_count();
> - tracing_generic_entry_update(ent, 0, pc);
> - ent->type = TRACE_BLK;
> + t = ring_buffer_event_data(event);
> goto record_it;
> }
>
> @@ -241,12 +237,7 @@ record_it:
> memcpy((void *) t + sizeof(*t), pdu_data, pdu_len);
>
> if (blk_tr) {
> - ring_buffer_unlock_commit(blk_tr->buffer, event);
> - if (pid != 0 &&
> - !(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC) &&
> - (trace_flags & TRACE_ITER_STACKTRACE) != 0)
> - __trace_stack(blk_tr, 0, 5, pc);
> - trace_wake_up();
> + trace_buffer_unlock_commit(blk_tr, event, 0, pc);
> return;
> }
> }
> diff --git a/kernel/trace/kmemtrace.c b/kernel/trace/kmemtrace.c
> index 256749d..ae201b3 100644
> --- a/kernel/trace/kmemtrace.c
> +++ b/kernel/trace/kmemtrace.c
> @@ -276,13 +276,12 @@ void kmemtrace_mark_alloc_node(enum kmemtrace_type_id type_id,
> if (!kmem_tracing_enabled)
> return;
>
> - event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry));
> + event = trace_buffer_lock_reserve(tr, TRACE_KMEM_ALLOC,
> + sizeof(*entry), 0, 0);
> if (!event)
> return;
> entry = ring_buffer_event_data(event);
> - tracing_generic_entry_update(&entry->ent, 0, 0);
>
> - entry->ent.type = TRACE_KMEM_ALLOC;
> entry->call_site = call_site;
> entry->ptr = ptr;
> entry->bytes_req = bytes_req;
> @@ -290,9 +289,7 @@ void kmemtrace_mark_alloc_node(enum kmemtrace_type_id type_id,
> entry->gfp_flags = gfp_flags;
> entry->node = node;
>
> - ring_buffer_unlock_commit(tr->buffer, event);
> -
> - trace_wake_up();
> + trace_buffer_unlock_commit(tr, event, 0, 0);
> }
> EXPORT_SYMBOL(kmemtrace_mark_alloc_node);
>
> @@ -307,20 +304,16 @@ void kmemtrace_mark_free(enum kmemtrace_type_id type_id,
> if (!kmem_tracing_enabled)
> return;
>
> - event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry));
> + event = trace_buffer_lock_reserve(tr, TRACE_KMEM_FREE,
> + sizeof(*entry), 0, 0);
> if (!event)
> return;
> entry = ring_buffer_event_data(event);
> - tracing_generic_entry_update(&entry->ent, 0, 0);
> -
> - entry->ent.type = TRACE_KMEM_FREE;
> entry->type_id = type_id;
> entry->call_site = call_site;
> entry->ptr = ptr;
>
> - ring_buffer_unlock_commit(tr->buffer, event);
> -
> - trace_wake_up();
> + trace_buffer_unlock_commit(tr, event, 0, 0);
> }
> EXPORT_SYMBOL(kmemtrace_mark_free);
>
> diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
> index eb453a2..8fad377 100644
> --- a/kernel/trace/trace.c
> +++ b/kernel/trace/trace.c
> @@ -776,6 +776,39 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
> (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0);
> }
>
> +struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr,
> + unsigned char type,
> + unsigned long len,
> + unsigned long flags, int pc)
> +{
> + struct ring_buffer_event *event;
> +
> + event = ring_buffer_lock_reserve(tr->buffer, len);
> + if (event != NULL) {
> + struct trace_entry *ent = ring_buffer_event_data(event);
> +
> + tracing_generic_entry_update(ent, flags, pc);
> + ent->type = type;
> + }
> +
> + return event;
> +}
> +static void ftrace_trace_stack(struct trace_array *tr,
> + unsigned long flags, int skip, int pc);
> +static void ftrace_trace_userstack(struct trace_array *tr,
> + unsigned long flags, int pc);
> +
> +void trace_buffer_unlock_commit(struct trace_array *tr,
> + struct ring_buffer_event *event,
> + unsigned long flags, int pc)
> +{
> + ring_buffer_unlock_commit(tr->buffer, event);
> +
> + ftrace_trace_stack(tr, flags, 6, pc);
> + ftrace_trace_userstack(tr, flags, pc);
> + trace_wake_up();
> +}


I have mitigate feelings about this part. The name of this function could
have some sense if _most_ of the tracers were using the stack traces. But that's
not the case.

We have now this couple:

_ trace_buffer_lock_reserve() -> handles the ring-buffer reservation, the context info, and the type
_ trace_buffer_unlock_commit() -> unlock, commit, wake and... stacktraces?

In my opinion, the latter doesn't follow the logic meaning of the first.
And the result is a mixup of (trace_buffer | ring_buffer)(lock/unlock/reserve/commit).

You are sometimes using trace_buffer_lock_reserve followed by ring_buffer_unlock_commit.
That looks a bit weird: we are using a high level function followed by its conclusion
on the form of the low lovel function.

I think the primary role of this new couple should be to simplify the low level ring buffer
bits as it does. But the stack things should stay separated.

> +
> void
> trace_function(struct trace_array *tr,
> unsigned long ip, unsigned long parent_ip, unsigned long flags,
> @@ -788,12 +821,11 @@ trace_function(struct trace_array *tr,
> if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
> return;
>
> - event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry));
> + event = trace_buffer_lock_reserve(tr, TRACE_FN, sizeof(*entry),
> + flags, pc);
> if (!event)
> return;
> entry = ring_buffer_event_data(event);
> - tracing_generic_entry_update(&entry->ent, flags, pc);
> - entry->ent.type = TRACE_FN;
> entry->ip = ip;
> entry->parent_ip = parent_ip;
> ring_buffer_unlock_commit(tr->buffer, event);
> @@ -811,12 +843,11 @@ static void __trace_graph_entry(struct trace_array *tr,
> if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
> return;
>
> - event = ring_buffer_lock_reserve(global_trace.buffer, sizeof(*entry));
> + event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_ENT,
> + sizeof(*entry), flags, pc);
> if (!event)
> return;
> entry = ring_buffer_event_data(event);
> - tracing_generic_entry_update(&entry->ent, flags, pc);
> - entry->ent.type = TRACE_GRAPH_ENT;
> entry->graph_ent = *trace;
> ring_buffer_unlock_commit(global_trace.buffer, event);
> }
> @@ -832,12 +863,11 @@ static void __trace_graph_return(struct trace_array *tr,
> if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
> return;
>
> - event = ring_buffer_lock_reserve(global_trace.buffer, sizeof(*entry));
> + event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_RET,
> + sizeof(*entry), flags, pc);
> if (!event)
> return;
> entry = ring_buffer_event_data(event);
> - tracing_generic_entry_update(&entry->ent, flags, pc);
> - entry->ent.type = TRACE_GRAPH_RET;
> entry->ret = *trace;
> ring_buffer_unlock_commit(global_trace.buffer, event);
> }
> @@ -861,13 +891,11 @@ static void __ftrace_trace_stack(struct trace_array *tr,
> struct stack_entry *entry;
> struct stack_trace trace;
>
> - event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry));
> + event = trace_buffer_lock_reserve(tr, TRACE_STACK,
> + sizeof(*entry), flags, pc);
> if (!event)
> return;
> entry = ring_buffer_event_data(event);
> - tracing_generic_entry_update(&entry->ent, flags, pc);
> - entry->ent.type = TRACE_STACK;
> -
> memset(&entry->caller, 0, sizeof(entry->caller));
>
> trace.nr_entries = 0;
> @@ -908,12 +936,11 @@ static void ftrace_trace_userstack(struct trace_array *tr,
> if (!(trace_flags & TRACE_ITER_USERSTACKTRACE))
> return;
>
> - event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry));
> + event = trace_buffer_lock_reserve(tr, TRACE_USER_STACK,
> + sizeof(*entry), flags, pc);
> if (!event)
> return;
> entry = ring_buffer_event_data(event);
> - tracing_generic_entry_update(&entry->ent, flags, pc);
> - entry->ent.type = TRACE_USER_STACK;
>
> memset(&entry->caller, 0, sizeof(entry->caller));
>
> @@ -941,20 +968,15 @@ ftrace_trace_special(void *__tr,
> struct trace_array *tr = __tr;
> struct special_entry *entry;
>
> - event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry));
> + event = trace_buffer_lock_reserve(tr, TRACE_SPECIAL,
> + sizeof(*entry), 0, pc);
> if (!event)
> return;
> entry = ring_buffer_event_data(event);
> - tracing_generic_entry_update(&entry->ent, 0, pc);
> - entry->ent.type = TRACE_SPECIAL;
> entry->arg1 = arg1;
> entry->arg2 = arg2;
> entry->arg3 = arg3;
> - ring_buffer_unlock_commit(tr->buffer, event);
> - ftrace_trace_stack(tr, 0, 4, pc);
> - ftrace_trace_userstack(tr, 0, pc);
> -
> - trace_wake_up();
> + trace_buffer_unlock_commit(tr, event, 0, pc);
> }
>
> void
> @@ -973,12 +995,11 @@ tracing_sched_switch_trace(struct trace_array *tr,
> struct ring_buffer_event *event;
> struct ctx_switch_entry *entry;
>
> - event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry));
> + event = trace_buffer_lock_reserve(tr, TRACE_CTX,
> + sizeof(*entry), flags, pc);
> if (!event)
> return;
> entry = ring_buffer_event_data(event);
> - tracing_generic_entry_update(&entry->ent, flags, pc);
> - entry->ent.type = TRACE_CTX;
> entry->prev_pid = prev->pid;
> entry->prev_prio = prev->prio;
> entry->prev_state = prev->state;
> @@ -986,9 +1007,7 @@ tracing_sched_switch_trace(struct trace_array *tr,
> entry->next_prio = next->prio;
> entry->next_state = next->state;
> entry->next_cpu = task_cpu(next);
> - ring_buffer_unlock_commit(tr->buffer, event);
> - ftrace_trace_stack(tr, flags, 5, pc);
> - ftrace_trace_userstack(tr, flags, pc);
> + trace_buffer_unlock_commit(tr, event, flags, pc);
> }
>
> void
> @@ -1000,12 +1019,11 @@ tracing_sched_wakeup_trace(struct trace_array *tr,
> struct ring_buffer_event *event;
> struct ctx_switch_entry *entry;
>
> - event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry));
> + event = trace_buffer_lock_reserve(tr, TRACE_WAKE,
> + sizeof(*entry), flags, pc);
> if (!event)
> return;
> entry = ring_buffer_event_data(event);
> - tracing_generic_entry_update(&entry->ent, flags, pc);
> - entry->ent.type = TRACE_WAKE;
> entry->prev_pid = curr->pid;
> entry->prev_prio = curr->prio;
> entry->prev_state = curr->state;
> @@ -1013,11 +1031,7 @@ tracing_sched_wakeup_trace(struct trace_array *tr,
> entry->next_prio = wakee->prio;
> entry->next_state = wakee->state;
> entry->next_cpu = task_cpu(wakee);
> - ring_buffer_unlock_commit(tr->buffer, event);
> - ftrace_trace_stack(tr, flags, 6, pc);
> - ftrace_trace_userstack(tr, flags, pc);
> -
> - trace_wake_up();
> + trace_buffer_unlock_commit(tr, event, flags, pc);
> }
>
> void
> @@ -2825,12 +2839,10 @@ int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args)
> trace_buf[len] = 0;
>
> size = sizeof(*entry) + len + 1;
> - event = ring_buffer_lock_reserve(tr->buffer, size);
> + event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc);
> if (!event)
> goto out_unlock;
> entry = ring_buffer_event_data(event);
> - tracing_generic_entry_update(&entry->ent, irq_flags, pc);
> - entry->ent.type = TRACE_PRINT;
> entry->ip = ip;
> entry->depth = depth;
>
> diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
> index df627a9..e03f157 100644
> --- a/kernel/trace/trace.h
> +++ b/kernel/trace/trace.h
> @@ -403,6 +403,17 @@ int tracing_open_generic(struct inode *inode, struct file *filp);
> struct dentry *tracing_init_dentry(void);
> void init_tracer_sysprof_debugfs(struct dentry *d_tracer);
>
> +struct ring_buffer_event;
> +
> +struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr,
> + unsigned char type,
> + unsigned long len,
> + unsigned long flags,
> + int pc);
> +void trace_buffer_unlock_commit(struct trace_array *tr,
> + struct ring_buffer_event *event,
> + unsigned long flags, int pc);
> +
> struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
> struct trace_array_cpu *data);
>
> diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c
> index 4e08deb..7a30fc4 100644
> --- a/kernel/trace/trace_boot.c
> +++ b/kernel/trace/trace_boot.c
> @@ -143,17 +143,13 @@ void trace_boot_call(struct boot_trace_call *bt, initcall_t fn)
> sprint_symbol(bt->func, (unsigned long)fn);
> preempt_disable();
>
> - event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry));
> + event = trace_buffer_lock_reserve(tr, TRACE_BOOT_CALL,
> + sizeof(*entry), 0, 0);
> if (!event)
> goto out;
> entry = ring_buffer_event_data(event);
> - tracing_generic_entry_update(&entry->ent, 0, 0);
> - entry->ent.type = TRACE_BOOT_CALL;
> entry->boot_call = *bt;
> - ring_buffer_unlock_commit(tr->buffer, event);
> -
> - trace_wake_up();
> -
> + trace_buffer_unlock_commit(tr, event, 0, 0);
> out:
> preempt_enable();
> }
> @@ -170,17 +166,13 @@ void trace_boot_ret(struct boot_trace_ret *bt, initcall_t fn)
> sprint_symbol(bt->func, (unsigned long)fn);
> preempt_disable();
>
> - event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry));
> + event = trace_buffer_lock_reserve(tr, TRACE_BOOT_RET,
> + sizeof(*entry), 0, 0);
> if (!event)
> goto out;
> entry = ring_buffer_event_data(event);
> - tracing_generic_entry_update(&entry->ent, 0, 0);
> - entry->ent.type = TRACE_BOOT_RET;
> entry->boot_ret = *bt;
> - ring_buffer_unlock_commit(tr->buffer, event);
> -
> - trace_wake_up();
> -
> + trace_buffer_unlock_commit(tr, event, 0, 0);
> out:
> preempt_enable();
> }
> diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c
> index 770e52a..48b2196 100644
> --- a/kernel/trace/trace_branch.c
> +++ b/kernel/trace/trace_branch.c
> @@ -52,14 +52,13 @@ probe_likely_condition(struct ftrace_branch_data *f, int val, int expect)
> if (atomic_inc_return(&tr->data[cpu]->disabled) != 1)
> goto out;
>
> - event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry));
> + pc = preempt_count();
> + event = trace_buffer_lock_reserve(tr, TRACE_BRANCH,
> + sizeof(*entry), flags, pc);
> if (!event)
> goto out;
>
> - pc = preempt_count();
> entry = ring_buffer_event_data(event);
> - tracing_generic_entry_update(&entry->ent, flags, pc);
> - entry->ent.type = TRACE_BRANCH;
>
> /* Strip off the path, only save the file */
> p = f->file + strlen(f->file);
> diff --git a/kernel/trace/trace_hw_branches.c b/kernel/trace/trace_hw_branches.c
> index e720c00..2aa1c9f 100644
> --- a/kernel/trace/trace_hw_branches.c
> +++ b/kernel/trace/trace_hw_branches.c
> @@ -189,16 +189,15 @@ void trace_hw_branch(u64 from, u64 to)
> if (atomic_inc_return(&tr->data[cpu]->disabled) != 1)
> goto out;
>
> - event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry));
> + event = trace_buffer_lock_reserve(tr, TRACE_HW_BRANCHES,
> + sizeof(*entry), 0, 0);
> if (!event)
> goto out;
> entry = ring_buffer_event_data(event);
> - tracing_generic_entry_update(&entry->ent, 0, from);
> - entry->ent.type = TRACE_HW_BRANCHES;
> entry->ent.cpu = cpu;
> entry->from = from;
> entry->to = to;
> - ring_buffer_unlock_commit(tr->buffer, event);
> + trace_buffer_unlock_commit(tr, event, 0, 0);
>
> out:
> atomic_dec(&tr->data[cpu]->disabled);
> diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c
> index 104ddeb..c401b90 100644
> --- a/kernel/trace/trace_mmiotrace.c
> +++ b/kernel/trace/trace_mmiotrace.c
> @@ -307,19 +307,17 @@ static void __trace_mmiotrace_rw(struct trace_array *tr,
> {
> struct ring_buffer_event *event;
> struct trace_mmiotrace_rw *entry;
> + int pc = preempt_count();
>
> - event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry));
> + event = trace_buffer_lock_reserve(tr, TRACE_MMIO_RW,
> + sizeof(*entry), 0, pc);
> if (!event) {
> atomic_inc(&dropped_count);
> return;
> }
> entry = ring_buffer_event_data(event);
> - tracing_generic_entry_update(&entry->ent, 0, preempt_count());
> - entry->ent.type = TRACE_MMIO_RW;
> entry->rw = *rw;
> - ring_buffer_unlock_commit(tr->buffer, event);
> -
> - trace_wake_up();
> + trace_buffer_unlock_commit(tr, event, 0, pc);
> }
>
> void mmio_trace_rw(struct mmiotrace_rw *rw)
> @@ -335,19 +333,17 @@ static void __trace_mmiotrace_map(struct trace_array *tr,
> {
> struct ring_buffer_event *event;
> struct trace_mmiotrace_map *entry;
> + int pc = preempt_count();
>
> - event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry));
> + event = trace_buffer_lock_reserve(tr, TRACE_MMIO_MAP,
> + sizeof(*entry), 0, pc);
> if (!event) {
> atomic_inc(&dropped_count);
> return;
> }
> entry = ring_buffer_event_data(event);
> - tracing_generic_entry_update(&entry->ent, 0, preempt_count());
> - entry->ent.type = TRACE_MMIO_MAP;
> entry->map = *map;
> - ring_buffer_unlock_commit(tr->buffer, event);
> -
> - trace_wake_up();
> + trace_buffer_unlock_commit(tr, event, 0, pc);
> }
>
> void mmio_trace_mapping(struct mmiotrace_map *map)
> diff --git a/kernel/trace/trace_power.c b/kernel/trace/trace_power.c
> index 3b1a292..bfc21f8 100644
> --- a/kernel/trace/trace_power.c
> +++ b/kernel/trace/trace_power.c
> @@ -124,17 +124,13 @@ void trace_power_end(struct power_trace *it)
> it->end = ktime_get();
> data = tr->data[smp_processor_id()];
>
> - event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry));
> + event = trace_buffer_lock_reserve(tr, TRACE_POWER,
> + sizeof(*entry), 0, 0);
> if (!event)
> goto out;
> entry = ring_buffer_event_data(event);
> - tracing_generic_entry_update(&entry->ent, 0, 0);
> - entry->ent.type = TRACE_POWER;
> entry->state_data = *it;
> - ring_buffer_unlock_commit(tr->buffer, event);
> -
> - trace_wake_up();
> -
> + trace_buffer_unlock_commit(tr, event, 0, 0);
> out:
> preempt_enable();
> }
> @@ -159,17 +155,13 @@ void trace_power_mark(struct power_trace *it, unsigned int type,
> it->end = it->stamp;
> data = tr->data[smp_processor_id()];
>
> - event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry));
> + event = trace_buffer_lock_reserve(tr, TRACE_POWER,
> + sizeof(*entry), 0, 0);
> if (!event)
> goto out;
> entry = ring_buffer_event_data(event);
> - tracing_generic_entry_update(&entry->ent, 0, 0);
> - entry->ent.type = TRACE_POWER;
> entry->state_data = *it;
> - ring_buffer_unlock_commit(tr->buffer, event);
> -
> - trace_wake_up();
> -
> + trace_buffer_unlock_commit(tr, event, 0, 0);
> out:
> preempt_enable();
> }
> --
> 1.6.0.6
>


Other than what I said above, I find it a very valuable cleanup.
Thanks.

Frederic.

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