Messages in this thread | | | Date | Tue, 22 Jun 2021 15:45:46 +0100 | From | Mark Rutland <> | Subject | Re: [PATCH v2 0/9] thread_info: use helpers to snapshot thread flags |
| |
On Mon, Jun 21, 2021 at 06:54:53PM +0100, Will Deacon wrote: > On Mon, Jun 21, 2021 at 10:05:52AM +0100, Mark Rutland wrote: > > As thread_info::flags scan be manipulated by remote threads, it is > > necessary to use atomics or READ_ONCE() to ensure that code manipulates > > a consistent snapshot, but we open-code plain accesses to > > thread_info::flags across the kernel tree. > > > > Generally we get away with this, but tools like KCSAN legitimately warn > > that there is a data-race, and this is potentially fragile with compiler > > optimizations, LTO, etc. > > > > These patches introduce new helpers to snahpshot the thread flags, with > > the intent being that these should replace all plain accesses. > > > > Since v1 [1]: > > * Drop RFC > > * Make read_ti_thread_flags() __always_inline > > * Clarify commit messages > > * Fix typo in arm64 patch > > * Accumulate Reviewed-by / Acked-by tags > > * Drop powerpc patch to avoid potential conflicts (per [2]) > > > > [1] https://lore.kernel.org/r/20210609122001.18277-1-mark.rutland@arm.com > > [2] https://lore.kernel.org/r/87k0mvtgeb.fsf@mpe.ellerman.id.au > > > > Thanks, > > Mark. > > > > Mark Rutland (9): > > thread_info: add helpers to snapshot thread flags > > entry: snapshot thread flags > > sched: snapshot thread flags > > alpha: snapshot thread flags > > arm: snapshot thread flags > > arm64: snapshot thread flags > > FWIW, you have two identical arm64 patches in this series, just with a > different subject.
Whoops; I'd tried to bring arm64 in line with the other patches, but forgot to delete the stale patch file when I did that. I'll keep the "snapshot thread flags" version.
> For the one you decide to keep: > > Acked-by: Will Deacon <will@kernel.org>
Thanks!
Mark.
| |