../lib/rcu/rte_rcu_qsbr.c(101): warning C4334: '<<': result of 32-bit
shift implicitly converted to 64 bits (was 64-bit shift intended?)
../lib/rcu/rte_rcu_qsbr.c(107): warning C4334: '<<': result of 32-bit
shift implicitly converted to 64 bits (was 64-bit shift intended?)
../lib/rcu/rte_rcu_qsbr.c(145): warning C4334: '<<': result of 32-bit
shift implicitly converted to 64 bits (was 64-bit shift intended?)
These warnings are being issued by the MSVC compiler. Since the result is
being stored in a variable of type uint64_t, it makes sense to shift a
64-bit number instead of shifting a 32-bit number and then having the
compiler to convert the result implicitly to 64 bits.
UINT64_C was used in the fix as it is the portable way to define a 64-bit
constant (ULL suffix is architecture dependent).
>From reading the code this is also a bugfix:
(1 << id), where id = thread_id & 0x3f, was wrong when thread_id > 0x1f.
Fixes: 64994b56cfd7 ("rcu: add RCU library supporting QSBR mechanism")
Signed-off-by: Andre Muezerie <andre...@linux.microsoft.com>
Reviewed-by: Honnappa Nagarahalli <honnappa.nagaraha...@arm.com>
Reviewed-by: Morten Brørup <m...@smartsharesystems.com>
---
lib/rcu/rte_rcu_qsbr.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/lib/rcu/rte_rcu_qsbr.c b/lib/rcu/rte_rcu_qsbr.c
index 40d7c566c8..dbf31501a6 100644
--- a/lib/rcu/rte_rcu_qsbr.c
+++ b/lib/rcu/rte_rcu_qsbr.c
@@ -99,12 +99,12 @@ rte_rcu_qsbr_thread_register(struct rte_rcu_qsbr *v,
unsigned int thread_id)
/* Add the thread to the bitmap of registered threads */
old_bmap = rte_atomic_fetch_or_explicit(__RTE_QSBR_THRID_ARRAY_ELM(v,
i),
- (1UL << id),
rte_memory_order_release);
+ RTE_BIT64(id),
rte_memory_order_release);
/* Increment the number of threads registered only if the thread was
not already
* registered
*/
- if (!(old_bmap & (1UL << id)))
+ if (!(old_bmap & RTE_BIT64(id)))
rte_atomic_fetch_add_explicit(&v->num_threads, 1,
rte_memory_order_relaxed);
return 0;
@@ -137,12 +137,12 @@ rte_rcu_qsbr_thread_unregister(struct rte_rcu_qsbr *v,
unsigned int thread_id)
* reporting threads.
*/
old_bmap = rte_atomic_fetch_and_explicit(__RTE_QSBR_THRID_ARRAY_ELM(v,
i),
- ~(1UL << id),
rte_memory_order_release);
+ ~RTE_BIT64(id),
rte_memory_order_release);
/* Decrement the number of threads unregistered only if the thread was
not already
* unregistered
*/
- if (old_bmap & (1UL << id))
+ if (old_bmap & RTE_BIT64(id))
rte_atomic_fetch_sub_explicit(&v->num_threads, 1,
rte_memory_order_relaxed);
return 0;
@@ -198,7 +198,7 @@ rte_rcu_qsbr_dump(FILE *f, struct rte_rcu_qsbr *v)
t = rte_ctz64(bmap);
fprintf(f, "%u ", id + t);
- bmap &= ~(1UL << t);
+ bmap &= ~RTE_BIT64(t);
}
}
@@ -225,7 +225,7 @@ rte_rcu_qsbr_dump(FILE *f, struct rte_rcu_qsbr *v)
rte_atomic_load_explicit(
&v->qsbr_cnt[id + t].lock_cnt,
rte_memory_order_relaxed));
- bmap &= ~(1UL << t);
+ bmap &= ~RTE_BIT64(t);
}
}
--
2.34.1
