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perf: Factorize trace events raw sample buffer operations

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Introduce ftrace_perf_buf_prepare() and ftrace_perf_buf_submit() to
gather the common code that operates on raw events sampling buffer.
This cleans up redundant code between regular trace events, syscall
events and kprobe events.

Changelog v1->v2:
- Rename function name as per Masami and Frederic's suggestion
- Add __kprobes for ftrace_perf_buf_prepare() and make
  ftrace_perf_buf_submit() inline as per Masami's suggestion
- Export ftrace_perf_buf_prepare since modules will use it

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Acked-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4B60E92D.9000808@cn.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
This commit is contained in:
Xiao Guangrong
2010-01-28 09:32:29 +08:00
committed by Frederic Weisbecker
parent 339ce1a4dc
commit 430ad5a600
5 changed files with 88 additions and 187 deletions
Download Patch File Download Diff File Expand all files Collapse all files

71
kernel/trace/trace_syscalls.c
View File

@@ -433,12 +433,9 @@ static void prof_syscall_enter(struct pt_regs *regs, long id)
struct syscall_metadata *sys_data;
struct syscall_trace_enter *rec;
unsigned long flags;
char *trace_buf;
char *raw_data;
int syscall_nr;
int rctx;
int size;
int cpu;
syscall_nr = syscall_get_nr(current, regs);
if (!test_bit(syscall_nr, enabled_prof_enter_syscalls))
@@ -457,37 +454,15 @@ static void prof_syscall_enter(struct pt_regs *regs, long id)
"profile buffer not large enough"))
return;
/* Protect the per cpu buffer, begin the rcu read side */
local_irq_save(flags);
rec = (struct syscall_trace_enter *)ftrace_perf_buf_prepare(size,
sys_data->enter_event->id, &rctx, &flags);
if (!rec)
return;
rctx = perf_swevent_get_recursion_context();
if (rctx < 0)
goto end_recursion;
cpu = smp_processor_id();
trace_buf = rcu_dereference(perf_trace_buf);
if (!trace_buf)
goto end;
raw_data = per_cpu_ptr(trace_buf, cpu);
/* zero the dead bytes from align to not leak stack to user */
*(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
rec = (struct syscall_trace_enter *) raw_data;
tracing_generic_entry_update(&rec->ent, 0, 0);
rec->ent.type = sys_data->enter_event->id;
rec->nr = syscall_nr;
syscall_get_arguments(current, regs, 0, sys_data->nb_args,
(unsigned long *)&rec->args);
perf_tp_event(sys_data->enter_event->id, 0, 1, rec, size);
end:
perf_swevent_put_recursion_context(rctx);
end_recursion:
local_irq_restore(flags);
ftrace_perf_buf_submit(rec, size, rctx, 0, 1, flags);
}
int prof_sysenter_enable(struct ftrace_event_call *call)
@@ -531,11 +506,8 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret)
struct syscall_trace_exit *rec;
unsigned long flags;
int syscall_nr;
char *trace_buf;
char *raw_data;
int rctx;
int size;
int cpu;
syscall_nr = syscall_get_nr(current, regs);
if (!test_bit(syscall_nr, enabled_prof_exit_syscalls))
@@ -557,38 +529,15 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret)
"exit event has grown above profile buffer size"))
return;
/* Protect the per cpu buffer, begin the rcu read side */
local_irq_save(flags);
rec = (struct syscall_trace_exit *)ftrace_perf_buf_prepare(size,
sys_data->exit_event->id, &rctx, &flags);
if (!rec)
return;
rctx = perf_swevent_get_recursion_context();
if (rctx < 0)
goto end_recursion;
cpu = smp_processor_id();
trace_buf = rcu_dereference(perf_trace_buf);
if (!trace_buf)
goto end;
raw_data = per_cpu_ptr(trace_buf, cpu);
/* zero the dead bytes from align to not leak stack to user */
*(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
rec = (struct syscall_trace_exit *)raw_data;
tracing_generic_entry_update(&rec->ent, 0, 0);
rec->ent.type = sys_data->exit_event->id;
rec->nr = syscall_nr;
rec->ret = syscall_get_return_value(current, regs);
perf_tp_event(sys_data->exit_event->id, 0, 1, rec, size);
end:
perf_swevent_put_recursion_context(rctx);
end_recursion:
local_irq_restore(flags);
ftrace_perf_buf_submit(rec, size, rctx, 0, 1, flags);
}
int prof_sysexit_enable(struct ftrace_event_call *call)