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| author |   Kumar Kartikeya Dwivedi <memxor@gmail.com> | 2025-03-15 21:05:30 -0700 |
|---|---|---|
| committer |   Alexei Starovoitov <ast@kernel.org> | 2025-03-19 08:03:05 -0700 |
| commit | ecbd8047526d3e9681043c287dea7bc67ef33eb4 (patch) | |
| tree | e43a42794fc1b248f2040e43b0aa93da7175a270 /kernel | |
| parent | rqspinlock: Add a test-and-set fallback (diff) | |
| download | wireguard-linux-ecbd8047526d3e9681043c287dea7bc67ef33eb4.tar.xz wireguard-linux-ecbd8047526d3e9681043c287dea7bc67ef33eb4.zip | |
rqspinlock: Add basic support for CONFIG_PARAVIRT
We ripped out PV and virtualization related bits from rqspinlock in an
earlier commit, however, a fair lock performs poorly within a virtual
machine when the lock holder is preempted. As such, retain the
virt_spin_lock fallback to test and set lock, but with timeout and
deadlock detection. We can do this by simply depending on the
resilient_tas_spin_lock implementation from the previous patch.
We don't integrate support for CONFIG_PARAVIRT_SPINLOCKS yet, as that
requires more involved algorithmic changes and introduces more
complexity. It can be done when the need arises in the future.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20250316040541.108729-15-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/rqspinlock.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/kernel/bpf/rqspinlock.c b/kernel/bpf/rqspinlock.c index 714dfab5caa8..ed21ee010063 100644 --- a/kernel/bpf/rqspinlock.c +++ b/kernel/bpf/rqspinlock.c @@ -352,6 +352,9 @@ int __lockfunc resilient_queued_spin_lock_slowpath(rqspinlock_t *lock, u32 val) BUILD_BUG_ON(CONFIG_NR_CPUS >= (1U << _Q_TAIL_CPU_BITS)); + if (resilient_virt_spin_lock_enabled()) + return resilient_virt_spin_lock(lock); + RES_INIT_TIMEOUT(ts); /* |