diff options
| author | Peter Zijlstra | 2018-11-02 14:26:53 +0100 |
|---|---|---|
| committer | Ingo Molnar | 2018-11-04 00:54:34 +0100 |
| commit | b987ffc18fb3b3b76b059aa9e372dbee26f7c4f2 (patch) | |
| tree | 548d9ce6fbb9c51977cb880e450f81abba0f753d /arch/x86 | |
| parent | 5b7449810ae6d652629c550d3974c8453836d229 (diff) | |
x86/qspinlock: Fix compile error
With a compiler that has asm-goto but not asm-cc-output and
CONFIG_PROFILE_ALL_BRANCHES=y we get a compiler error:
arch/x86/include/asm/rmwcc.h:23:17: error: jump into statement expression
Fix this by writing the if() as a boolean multiplication instead.
Reported-by: kbuild test robot <lkp@intel.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: Will Deacon <will.deacon@arm.com>
Cc: linux-kernel@vger.kernel.org
Fixes: 7aa54be29765 ("locking/qspinlock, x86: Provide liveness guarantee")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/include/asm/qspinlock.h | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/arch/x86/include/asm/qspinlock.h b/arch/x86/include/asm/qspinlock.h index 87623c6b13db..bd5ac6cc37db 100644 --- a/arch/x86/include/asm/qspinlock.h +++ b/arch/x86/include/asm/qspinlock.h @@ -13,12 +13,15 @@ #define queued_fetch_set_pending_acquire queued_fetch_set_pending_acquire static __always_inline u32 queued_fetch_set_pending_acquire(struct qspinlock *lock) { - u32 val = 0; - - if (GEN_BINARY_RMWcc(LOCK_PREFIX "btsl", lock->val.counter, c, - "I", _Q_PENDING_OFFSET)) - val |= _Q_PENDING_VAL; + u32 val; + /* + * We can't use GEN_BINARY_RMWcc() inside an if() stmt because asm goto + * and CONFIG_PROFILE_ALL_BRANCHES=y results in a label inside a + * statement expression, which GCC doesn't like. + */ + val = GEN_BINARY_RMWcc(LOCK_PREFIX "btsl", lock->val.counter, c, + "I", _Q_PENDING_OFFSET) * _Q_PENDING_VAL; val |= atomic_read(&lock->val) & ~_Q_PENDING_MASK; return val; |