Update the kvfree_call_rcu() function with head-less support. This allows RCU to reclaim objects without an embedded rcu_head. tree-RCU: We introduce two chains of arrays to store SLAB-backed and vmalloc pointers, each. Storage in either of these arrays does not require embedding an rcu_head within the object. Maintaining the arrays may become impossible due to high memory pressure. For such cases there is an emergency path. Objects with rcu_head inside are just queued on a backup rcu_head list. Later on that list is drained. As for the head-less variant, as the current context can sleep, the following emergency measures are applied: a) Synchronously wait until a grace period has elapsed. b) Call kvfree(). tiny-RCU: For double argument calls, there are no new changes in behavior. For single argument call, kvfree() is directly inlined on the current stack after a synchronize_rcu() call. Note that for tiny-RCU, any call to synchronize_rcu() is actually a quiescent state, therefore it does nothing. Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Co-developed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> |
||
|---|---|---|
| .. | ||
| acpi | ||
| asm-generic | ||
| clocksource | ||
| crypto | ||
| drm | ||
| dt-bindings | ||
| keys | ||
| kunit | ||
| kvm | ||
| linux | ||
| math-emu | ||
| media | ||
| misc | ||
| net | ||
| pcmcia | ||
| ras | ||
| rdma | ||
| scsi | ||
| soc | ||
| sound | ||
| target | ||
| trace | ||
| uapi | ||
| vdso | ||
| video | ||
| xen | ||