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| author | Chris Zankel <chris@zankel.net> | 2015-08-29 23:55:58 +0000 |
|---|---|---|
| committer | Chris Zankel <chris@zankel.net> | 2015-08-29 23:55:58 +0000 |
| commit | 650c919798c71fb34b77a6f2ba03a06907f06a76 (patch) | |
| tree | d1c60012d4d86846d25f1d0b783b5122c26a2e31 /kernel/trace/trace_branch.c | |
| parent | 895fb3159280fe7695b35ec7c87ec19e13ca5b6e (diff) | |
| parent | 64291f7db5bd8150a74ad2036f1037e6a0428df2 (diff) | |
Merge tag 'v4.2' into for_next
Linux 4.2
Diffstat (limited to 'kernel/trace/trace_branch.c')
| -rw-r--r-- | kernel/trace/trace_branch.c | 17 |
1 files changed, 10 insertions, 7 deletions
diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c index a87b43f49eb4..e2e12ad3186f 100644 --- a/kernel/trace/trace_branch.c +++ b/kernel/trace/trace_branch.c @@ -36,9 +36,12 @@ probe_likely_condition(struct ftrace_branch_data *f, int val, int expect) struct trace_branch *entry; struct ring_buffer *buffer; unsigned long flags; - int cpu, pc; + int pc; const char *p; + if (current->trace_recursion & TRACE_BRANCH_BIT) + return; + /* * I would love to save just the ftrace_likely_data pointer, but * this code can also be used by modules. Ugly things can happen @@ -49,10 +52,10 @@ probe_likely_condition(struct ftrace_branch_data *f, int val, int expect) if (unlikely(!tr)) return; - local_irq_save(flags); - cpu = raw_smp_processor_id(); - data = per_cpu_ptr(tr->trace_buffer.data, cpu); - if (atomic_inc_return(&data->disabled) != 1) + raw_local_irq_save(flags); + current->trace_recursion |= TRACE_BRANCH_BIT; + data = this_cpu_ptr(tr->trace_buffer.data); + if (atomic_read(&data->disabled)) goto out; pc = preempt_count(); @@ -81,8 +84,8 @@ probe_likely_condition(struct ftrace_branch_data *f, int val, int expect) __buffer_unlock_commit(buffer, event); out: - atomic_dec(&data->disabled); - local_irq_restore(flags); + current->trace_recursion &= ~TRACE_BRANCH_BIT; + raw_local_irq_restore(flags); } static inline |