[PATCH] bitops: Introduce BITS_PER_TYPE

Chris Wilson
2018-07-06T09:45:40Z

net_dim.h has a rather useful extension to BITS_PER_BYTE to compute the
number of bits in a type (BITS_PER_BYTE * sizeof(T)), so promote the
macro to bitops.h, alongside BITS_PER_BYTE, for wider usage.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Andy Gospodarek <gospo@broadcom.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
---
include/linux/bitops.h | 3 ++-
include/linux/net_dim.h | 1 -
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index 4cac4e1a72ff..091cb17d1a9b 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -11,7 +11,8 @@
#define BIT_ULL_MASK(nr) (1ULL << ((nr) % BITS_PER_LONG_LONG))
#define BIT_ULL_WORD(nr) ((nr) / BITS_PER_LONG_LONG)
#define BITS_PER_BYTE 8
-#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
+#define BITS_PER_TYPE(type) (sizeof(type) * BITS_PER_BYTE)
+#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_TYPE(long))
#endif

/*
diff --git a/include/linux/net_dim.h b/include/linux/net_dim.h
index 29ed8fd6379a..14f1734e740a 100644
--- a/include/linux/net_dim.h
+++ b/include/linux/net_dim.h
@@ -326,7 +326,6 @@ static inline void net_dim_sample(u16 event_ctr,
}

#define NET_DIM_NEVENTS 64
-#define BITS_PER_TYPE(type) (sizeof(type) * BITS_PER_BYTE)
#define BIT_GAP(bits, end, start) ((((end) - (start)) + BIT_ULL(bits)) & (BIT_ULL(bits) - 1))

static inline void net_dim_calc_stats(struct net_dim_sample *start,
--
2.18.0