Messages in this thread Patch in this message | | | From | Rong Tao <> | Subject | [PATCH 1/2] stop_machine: Use non-atomic read multi_stop_data::state clearly | Date | Fri, 20 Oct 2023 22:43:33 +0800 |
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From: Rong Tao <rongtao@cestc.cn>
commit b1fc58333575 ("stop_machine: Avoid potential race behaviour") solved the race behaviour problem, to better show that race behaviour does not exist, pass the 'curstate' directly to ack_state() instead of refetching msdata->state in ack_state().
Signed-off-by: Rong Tao <rongtao@cestc.cn> --- kernel/stop_machine.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c index cedb17ba158a..268c2e581698 100644 --- a/kernel/stop_machine.c +++ b/kernel/stop_machine.c @@ -188,10 +188,11 @@ static void set_state(struct multi_stop_data *msdata, } /* Last one to ack a state moves to the next state. */ -static void ack_state(struct multi_stop_data *msdata) +static void ack_state(struct multi_stop_data *msdata, + enum multi_stop_state curstate) { if (atomic_dec_and_test(&msdata->thread_ack)) - set_state(msdata, msdata->state + 1); + set_state(msdata, curstate + 1); } notrace void __weak stop_machine_yield(const struct cpumask *cpumask) @@ -242,7 +243,7 @@ static int multi_cpu_stop(void *data) default: break; } - ack_state(msdata); + ack_state(msdata, curstate); } else if (curstate > MULTI_STOP_PREPARE) { /* * At this stage all other CPUs we depend on must spin -- 2.41.0
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