[$] Faster RCUs and lockless memory allocation

Puranjay Mohan presented improvements to read-copy-update (RCU) performance at the 2026 Linux Storage, Filesystem, Memory-Management, and BPF Summit. The new kmalloc_nolock() function, discussed by Harry Yoo and Alexei Starovoitov, enables lockless memory allocation from any kernel context by interacting with the RCU subsystem. The two sessions together highlight advances in kernel memory management and synchronization.

Puranjay Mohan shared some of the work https://lwn.net/ml/all/20260417231203.785172-1-puranjay@kernel.org/ he's been doing recently on improving the performance of read-copy-update RCU at the 2026 Linux Storage, Filesystem, Memory-Management, and BPF Summit https://events.linuxfoundation.org/lsfmmbpf/ ; his talk would have been nice context to have earlier in the day when Harry Yoo and Alexei Starovoitov led a session about the new kmalloc nolock function https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=af92793e52c3 that allows for lockless allocation from any kernel context, and which interacts with the RCU subsystem to allow that. This article therefore covers the two sessions together and in the reverse order, to provide that missing context.