include/asm-generic/qrwlock.h was trying to get arch_spin_is_locked via
asm-generic/qspinlock.h. However, this does not work because architectures
might be using queued rwlocks but not queued spinlocks (csky), or because they
might be defining their own queued_* macros before including asm/qspinlock.h.
To fix this, ensure that asm/spinlock.h always includes qrwlock.h after
defining arch_spin_is_locked (either directly for csky, or via
asm/qspinlock.h for other architectures). The only inclusion elsewhere
is in kernel/locking/qrwlock.c. That one is really unnecessary because
the file is only compiled in SMP configurations (config QUEUED_RWLOCKS
depends on SMP) and in that case linux/spinlock.h already includes
asm/qrwlock.h if needed, via asm/spinlock.h.
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Waiman Long <longman@redhat.com>
Fixes: 26128cb6c7 ("locking/rwlocks: Add contention detection for rwlocks")
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Ben Gardon <bgardon@google.com>
[Add arch/sparc and kernel/locking parts per discussion with Waiman. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Drop custom spinlock/rwlock code and use ones from asm-generic. This way
there is less code duplication (atomic primitives are reused).
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Outside of the locking code itself, {read,spin,write}_can_lock() have no
users in tree. Apparmor (the last remaining user of write_can_lock()) got
moved over to lockdep by the previous patch.
This patch removes the use of {read,spin,write}_can_lock() from the
BUILD_LOCK_OPS macro, deferring to the trylock operation for testing the
lock status, and subsequently removes the unused macros altogether. They
aren't guaranteed to work in a concurrent environment and can give
incorrect results in the case of qrwlock.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1507055129-12300-2-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Move all header files for xtensa to arch/xtensa/include and platform and
variant header files to the appropriate arch/xtensa/platforms/ and
arch/xtensa/variants/ directories.
Moving the files gets also rid of all uses of symlinks in the Makefile.
This has been completed already for the majority of the architectures
and xtensa is one out of six missing.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Chris Zankel <chris@zankel.net>
