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module: Remove preempt_disable() from module reference counting.

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The preempt_disable() section in module_put() was added in commit
   e1783a240f ("module: Use this_cpu_xx to dynamically allocate counters")

while the per-CPU counter were switched to another API. The API requires
that during the RMW operation the CPU remained the same.

This counting API was later replaced with atomic_t in commit
   2f35c41f58 ("module: Replace module_ref with atomic_t refcnt")

Since this atomic_t replacement there is no need to keep preemption
disabled while the reference counter is modified.

Remove preempt_disable() from module_put(), __module_get() and
try_module_get().

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
This commit is contained in:
Sebastian Andrzej Siewior 2023-05-09 15:49:02 +02:00 committed by Luis Chamberlain
parent d36f6efbe0
commit cb0b50b813
1 changed files with 0 additions and 7 deletions
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7
kernel/module/main.c
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@ -820,10 +820,8 @@ static struct module_attribute modinfo_refcnt =
void __module_get(struct module *module)
{
if (module) {
preempt_disable();
atomic_inc(&module->refcnt);
trace_module_get(module, _RET_IP_);
preempt_enable();
}
}
EXPORT_SYMBOL(__module_get);
@ -833,15 +831,12 @@ bool try_module_get(struct module *module)
bool ret = true;
if (module) {
preempt_disable();
/* Note: here, we can fail to get a reference */
if (likely(module_is_live(module) &&
atomic_inc_not_zero(&module->refcnt) != 0))
trace_module_get(module, _RET_IP_);
else
ret = false;
preempt_enable();
}
return ret;
}
@ -852,11 +847,9 @@ void module_put(struct module *module)
int ret;
if (module) {
preempt_disable();
ret = atomic_dec_if_positive(&module->refcnt);
WARN_ON(ret < 0); /* Failed to put refcount */
trace_module_put(module, _RET_IP_);
preempt_enable();
}
}
EXPORT_SYMBOL(module_put);