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perf/bpf: Remove preempt disable around BPF invocation

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The BPF invocation from the perf event overflow handler does not require to
disable preemption because this is called from NMI or at least hard
interrupt context which is already non-preemptible.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.151953573@linutronix.de
This commit is contained in:
Thomas Gleixner 2020-02-24 15:01:38 +01:00 committed by Alexei Starovoitov
parent b0a81b94cc
commit 1d7bf6b7d3
1 changed files with 0 additions and 2 deletions
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2
kernel/events/core.c
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@ -9206,7 +9206,6 @@ static void bpf_overflow_handler(struct perf_event *event,
int ret = 0;
ctx.regs = perf_arch_bpf_user_pt_regs(regs);
preempt_disable();
if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1))
goto out;
rcu_read_lock();
@ -9214,7 +9213,6 @@ static void bpf_overflow_handler(struct perf_event *event,
rcu_read_unlock();
out:
__this_cpu_dec(bpf_prog_active);
preempt_enable();
if (!ret)
return;