Re: [PATCH v7 bpf-next 06/10] tracepoint: compute num_args at build time
flat view
From: Steven Rostedt <rostedt@goodmis.org>
Date: 2018-03-28 19:38:32
Also in:
linux-api
On Wed, 28 Mar 2018 15:32:20 -0400 Steven Rostedt [off-list ref] wrote:
quoted hunk ↗ jump to hunk
-#define __DO_TRACE(tp, proto, args, cond, rcucheck) \ +#define __DO_TRACE(name, proto, args, cond, rcucheck) \ do { \ struct tracepoint_func *it_func_ptr; \ void *it_func; \@@ -140,7 +140,7 @@ extern void syscall_unregfunc(void); if (rcucheck) \ rcu_irq_enter_irqson(); \ rcu_read_lock_sched_notrace(); \ - it_func_ptr = rcu_dereference_sched((tp)->funcs); \ + it_func_ptr = rcu_dereference_sched(__trace_##name##_funcs); \
What we lose in data size, we may make up for in text (which is even more important). This will remove a dereference in the hot path. I'll make a few builds and run size on the vmlinux images to see how this pans out. -- Steve
if (it_func_ptr) { \
do { \