diff options
author | Nicholas Piggin <npiggin@gmail.com> | 2022-11-28 06:11:13 +0300 |
---|---|---|
committer | Michael Ellerman <mpe@ellerman.id.au> | 2022-12-02 09:48:02 +0300 |
commit | 9f61521c7a284e799050cd2adacc9a611bd2b491 (patch) | |
tree | ea553dc89ef9d27ee506c2f76b413869fc352d31 /arch/powerpc/lib | |
parent | 247f34f7b80357943234f93f247a1ae6b6c3a740 (diff) | |
download | linux-9f61521c7a284e799050cd2adacc9a611bd2b491.tar.xz |
powerpc/qspinlock: powerpc qspinlock implementation
Add a powerpc specific implementation of queued spinlocks. This is the
build framework with a very simple (non-queued) spinlock implementation
to begin with. Later changes add queueing, and other features and
optimisations one-at-a-time. It is done this way to more easily see how
the queued spinlocks are built, and to make performance and correctness
bisects more useful.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Drop paravirt.h & processor.h changes to fix 32-bit build]
[mpe: Fix 32-bit build of qspinlock.o & disallow GENERIC_LOCKBREAK per Nick]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/CONLLQB6DCJU.2ZPOS7T6S5GRR@bobo
Diffstat (limited to 'arch/powerpc/lib')
-rw-r--r-- | arch/powerpc/lib/Makefile | 4 | ||||
-rw-r--r-- | arch/powerpc/lib/qspinlock.c | 17 |
2 files changed, 20 insertions, 1 deletions
diff --git a/arch/powerpc/lib/Makefile b/arch/powerpc/lib/Makefile index 8560c912186d..4de71cbf6e8e 100644 --- a/arch/powerpc/lib/Makefile +++ b/arch/powerpc/lib/Makefile @@ -52,7 +52,9 @@ obj-$(CONFIG_PPC_BOOK3S_64) += copyuser_power7.o copypage_power7.o \ obj64-y += copypage_64.o copyuser_64.o mem_64.o hweight_64.o \ memcpy_64.o copy_mc_64.o -ifndef CONFIG_PPC_QUEUED_SPINLOCKS +ifdef CONFIG_PPC_QUEUED_SPINLOCKS +obj-$(CONFIG_SMP) += qspinlock.o +else obj64-$(CONFIG_SMP) += locks.o endif diff --git a/arch/powerpc/lib/qspinlock.c b/arch/powerpc/lib/qspinlock.c new file mode 100644 index 000000000000..1c669b5b4607 --- /dev/null +++ b/arch/powerpc/lib/qspinlock.c @@ -0,0 +1,17 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +#include <linux/export.h> +#include <linux/processor.h> +#include <asm/qspinlock.h> + +void queued_spin_lock_slowpath(struct qspinlock *lock) +{ + while (!queued_spin_trylock(lock)) + cpu_relax(); +} +EXPORT_SYMBOL(queued_spin_lock_slowpath); + +#ifdef CONFIG_PARAVIRT_SPINLOCKS +void pv_spinlocks_init(void) +{ +} +#endif |