diff options
| author | Peter Zijlstra <a.p.zijlstra@chello.nl> | 2009-11-23 11:37:29 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-11-23 11:49:57 +0100 |
| commit | 4ed7c92d68a5387ba5f7030dc76eab03558e27f5 (patch) | |
| tree | 38d758819c41261275c2dbd6f64976f824c5fd27 /kernel/trace/trace_syscalls.c | |
| parent | f67218c3e93abaf0f480bb94b53d234853ffe4de (diff) | |
perf_events: Undo some recursion damage
Make perf_swevent_get_recursion_context return a context number
and disable preemption.
This could be used to remove the IRQ disable from the trace bit
and index the per-cpu buffer with.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20091123103819.993226816@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/trace/trace_syscalls.c')
| -rw-r--r-- | kernel/trace/trace_syscalls.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index 41b6dd963da..9189cbe8607 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -481,8 +481,8 @@ static void prof_syscall_enter(struct pt_regs *regs, long id) unsigned long flags; char *trace_buf; char *raw_data; - int *recursion; int syscall_nr; + int rctx; int size; int cpu; @@ -506,7 +506,8 @@ static void prof_syscall_enter(struct pt_regs *regs, long id) /* Protect the per cpu buffer, begin the rcu read side */ local_irq_save(flags); - if (perf_swevent_get_recursion_context(&recursion)) + rctx = perf_swevent_get_recursion_context(); + if (rctx < 0) goto end_recursion; cpu = smp_processor_id(); @@ -530,7 +531,7 @@ static void prof_syscall_enter(struct pt_regs *regs, long id) perf_tp_event(sys_data->enter_id, 0, 1, rec, size); end: - perf_swevent_put_recursion_context(recursion); + perf_swevent_put_recursion_context(rctx); end_recursion: local_irq_restore(flags); } @@ -582,7 +583,7 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret) int syscall_nr; char *trace_buf; char *raw_data; - int *recursion; + int rctx; int size; int cpu; @@ -609,7 +610,8 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret) /* Protect the per cpu buffer, begin the rcu read side */ local_irq_save(flags); - if (perf_swevent_get_recursion_context(&recursion)) + rctx = perf_swevent_get_recursion_context(); + if (rctx < 0) goto end_recursion; cpu = smp_processor_id(); @@ -634,7 +636,7 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret) perf_tp_event(sys_data->exit_id, 0, 1, rec, size); end: - perf_swevent_put_recursion_context(recursion); + perf_swevent_put_recursion_context(rctx); end_recursion: local_irq_restore(flags); } |