On Wed, Jul 27, 2022 at 08:36:18AM +0000, David Laight wrote: > From: Martin KaFai Lau > > Sent: 27 July 2022 07:09 > > > > Most of the codes in bpf_setsockopt(SOL_SOCKET) are duplicated from > > the sock_setsockopt(). The number of supported options are > > increasing ever and so as the duplicated codes. > > > > One issue in reusing sock_setsockopt() is that the bpf prog > > has already acquired the sk lock. sockptr_t is useful to handle this. > > sockptr_t already has a bit 'is_kernel' to handle the kernel-or-user > > memory copy. This patch adds a 'is_bpf' bit to tell if sk locking > > has already been ensured by the bpf prog. > > That is a really horrid place to hide an 'is locked' bit. > > You'd be better off splitting sock_setsockopt() to add a function > that is called with sk_lock held and the value read. > That would also save the churn of all the callers. There is no churn to the callers after this patch, so quite the opposite.
