On 2023-03-15 18:20, Stephen Hemminger wrote: > On Wed, 15 Mar 2023 18:03:41 +0100 > Mattias Rönnblom <mattias.ronnb...@ericsson.com> wrote: > >> Introduce a set of functions and macros that operate on sets of bits, >> kept in arrays of 64-bit elements. >> >> RTE bitset is designed for bitsets which are larger than what fits in >> a single machine word (i.e., 64 bits). For very large bitsets, the >> <rte_bitmap.h> API may be a more appropriate choice. >> >> RFC v2: >> * Replaced <sys/types.h> with <stddef.h> include, to properly get >> size_t typedef. >> * Add <rte_compat.h> to get __rte_experimental in <rte_bitset.h>. >> >> Signed-off-by: Mattias Rönnblom <mattias.ronnb...@ericsson.com> > > It would be good to have atomic version of these routines. > Other libraries could use that.
Atomic with the option to specify memory model, like in C11? Or just atomic, with no implications in regards to memory ordering (i.e., __ATOMIC_RELAXED). It seems to me that the implementation of such an API would require inline assembler (e.g., lock bts on x86) to do properly (no loops, no locks). Related: reading <rte_bitops.h> left me a little confused. The documentation and naming suggest the bit access operations are "relaxed", which I'm sure is true, but may leave the user believing the bit operations are atomic - which they aren't. Why would you otherwise mentioned the operations are relaxed?
