Hello! This pull request contains a single commit that uses "arch_" atomic operations to avoid the instrumentation that comes with the non-"arch_" versions. In preparation for that commit, it also has another commit that makes these "arch_" atomic operations available to generic code.
Without these commits, KCSAN uses can see pointless errors. This pull request is currently RFC pending ongoing -next testing. This was not entirely free of drama, with Stephen needing to handle a merge conflict: https://lore.kernel.org/lkml/20200626131425.73ee4...@canb.auug.org.au/ However, the resolution looks straightforward to me. In addition, these two commits pass rcutorture testing and associated KCSAN testing. The following changes since commit b3a9e3b9622ae10064826dccb4f7a52bd88c7407: Linux 5.8-rc1 (2020-06-14 12:45:04 -0700) are available in the git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git rcu/urgent for you to fetch changes up to b58e733fd774f3f4b49d9e7640d172a57e35200e: rcu: Fixup noinstr warnings (2020-06-25 08:24:32 -0700) ---------------------------------------------------------------- Peter Zijlstra (2): locking/atomics: Provide the arch_atomic_ interface to generic code rcu: Fixup noinstr warnings include/linux/atomic-fallback.h | 236 +++++++++++++++++++++++++++++++++- include/linux/compiler.h | 2 +- kernel/rcu/tree.c | 32 ++++- scripts/atomic/gen-atomic-fallback.sh | 31 +++++ 4 files changed, 292 insertions(+), 9 deletions(-)
