[PATCH 08/17] all: replace bitmap_weight with bitmap_weight_{eq, gt, ge, lt, le} where appropriate

Yury Norov
2021-12-18T21:21:33Z

Kernel code calls bitmap_weight() to compare the weight of bitmap with
a given number. We can do it more efficiently with bitmap_weight_{eq, ...}
because conditional bitmap_weight may stop traversing the bitmap earlier,
as soon as condition is met.

This patch replaces bitmap_weight with conditional versions where possible,
except for small bitmaps which size is not configurable and known at
constant time. In that case conditional version of bitmap_weight would not
benefit due to small_const_nbits() optimization; but readability may
suffer.

Signed-off-by: Yury Norov <yury.norov@gmail.com>
---
arch/x86/kernel/cpu/resctrl/rdtgroup.c | 2 +-
drivers/iio/dummy/iio_simple_dummy_buffer.c | 4 ++--
drivers/iio/industrialio-trigger.c | 2 +-
drivers/memstick/core/ms_block.c | 4 ++--
drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c | 2 +-
.../net/ethernet/marvell/octeontx2/nic/otx2_ethtool.c | 2 +-
.../net/ethernet/marvell/octeontx2/nic/otx2_flows.c | 4 ++--
drivers/net/ethernet/mellanox/mlx4/cmd.c | 10 +++-------
drivers/net/ethernet/mellanox/mlx4/eq.c | 4 ++--
drivers/net/ethernet/mellanox/mlx4/fw.c | 4 ++--
drivers/net/ethernet/mellanox/mlx4/main.c | 2 +-
drivers/perf/thunderx2_pmu.c | 4 ++--
drivers/staging/media/tegra-video/vi.c | 2 +-
13 files changed, 21 insertions(+), 25 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index e23ff03290b8..9d42e592c1cf 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2752,7 +2752,7 @@ static int __init_one_rdt_domain(struct rdt_domain *d, struct resctrl_schema *s,
* bitmap_weight() does not access out-of-bound memory.
*/
tmp_cbm = cfg->new_ctrl;
- if (bitmap_weight(&tmp_cbm, r->cache.cbm_len) < r->cache.min_cbm_bits) {
+ if (bitmap_weight_lt(&tmp_cbm, r->cache.cbm_len, r->cache.min_cbm_bits)) {
rdt_last_cmd_printf("No space on %s:%d\n", s->name, d->id);
return -ENOSPC;
}
diff --git a/drivers/iio/dummy/iio_simple_dummy_buffer.c b/drivers/iio/dummy/iio_simple_dummy_buffer.c
index 59aa60d4ca37..cd2470ddf82b 100644
--- a/drivers/iio/dummy/iio_simple_dummy_buffer.c
+++ b/drivers/iio/dummy/iio_simple_dummy_buffer.c
@@ -72,8 +72,8 @@ static irqreturn_t iio_simple_dummy_trigger_h(int irq, void *p)
int i, j;

for (i = 0, j = 0;
- i < bitmap_weight(indio_dev->active_scan_mask,
- indio_dev->masklength);
+ bitmap_weight_gt(indio_dev->active_scan_mask,
+ indio_dev->masklength, i);
i++, j++) {
j = find_next_bit(indio_dev->active_scan_mask,
indio_dev->masklength, j);
diff --git a/drivers/iio/industrialio-trigger.c b/drivers/iio/industrialio-trigger.c
index f504ed351b3e..98c54022fecf 100644
--- a/drivers/iio/industrialio-trigger.c
+++ b/drivers/iio/industrialio-trigger.c
@@ -331,7 +331,7 @@ int iio_trigger_detach_poll_func(struct iio_trigger *trig,
{
struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(pf->indio_dev);
bool no_other_users =
- bitmap_weight(trig->pool, CONFIG_IIO_CONSUMERS_PER_TRIGGER) == 1;
+ bitmap_weight_eq(trig->pool, CONFIG_IIO_CONSUMERS_PER_TRIGGER, 1);
int ret = 0;

if (trig->ops && trig->ops->set_trigger_state && no_other_users) {
diff --git a/drivers/memstick/core/ms_block.c b/drivers/memstick/core/ms_block.c
index 0cda6c6baefc..5cdd987e78f7 100644
--- a/drivers/memstick/core/ms_block.c
+++ b/drivers/memstick/core/ms_block.c
@@ -155,8 +155,8 @@ static int msb_validate_used_block_bitmap(struct msb_data *msb)
for (i = 0; i < msb->zone_count; i++)
total_free_blocks += msb->free_block_count[i];

- if (msb->block_count - bitmap_weight(msb->used_blocks_bitmap,
- msb->block_count) == total_free_blocks)
+ if (bitmap_weight_eq(msb->used_blocks_bitmap, msb->block_count,
+ msb->block_count - total_free_blocks))
return 0;

pr_err("BUG: free block counts don't match the bitmap");
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c
index 214a38de3f41..35297d8a488b 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c
@@ -246,7 +246,7 @@ int ixgbe_disable_sriov(struct ixgbe_adapter *adapter)
#endif

/* Disable VMDq flag so device will be set in VM mode */
- if (bitmap_weight(adapter->fwd_bitmask, adapter->num_rx_pools) == 1) {
+ if (bitmap_weight_eq(adapter->fwd_bitmask, adapter->num_rx_pools, 1)) {
adapter->flags &= ~IXGBE_FLAG_VMDQ_ENABLED;
adapter->flags &= ~IXGBE_FLAG_SRIOV_ENABLED;
rss = min_t(int, ixgbe_max_rss_indices(adapter),
diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_ethtool.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_ethtool.c
index d85db90632d6..a55fd1d0c653 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_ethtool.c
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_ethtool.c
@@ -287,7 +287,7 @@ static int otx2_set_channels(struct net_device *dev,
if (!channel->rx_count || !channel->tx_count)
return -EINVAL;

- if (bitmap_weight(&pfvf->rq_bmap, pfvf->hw.rx_queues) > 1) {
+ if (bitmap_weight_gt(&pfvf->rq_bmap, pfvf->hw.rx_queues, 1)) {
netdev_err(dev,
"Receive queues are in use by TC police action\n");
return -EINVAL;
diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c
index 80b2d64b4136..55c899a6fcdd 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_flows.c
@@ -1170,8 +1170,8 @@ int otx2_remove_flow(struct otx2_nic *pfvf, u32 location)
* interface mac address and configure CGX/RPM block in
* promiscuous mode
*/
- if (bitmap_weight(&flow_cfg->dmacflt_bmap,
- flow_cfg->dmacflt_max_flows) == 1)
+ if (bitmap_weight_eq(&flow_cfg->dmacflt_bmap,
+ flow_cfg->dmacflt_max_flows, 1))
otx2_update_rem_pfmac(pfvf, DMAC_ADDR_DEL);
} else {
err = otx2_remove_flow_msg(pfvf, flow->entry, false);
diff --git a/drivers/net/ethernet/mellanox/mlx4/cmd.c b/drivers/net/ethernet/mellanox/mlx4/cmd.c
index c56d2194cbfc..5bca0c68f00a 100644
--- a/drivers/net/ethernet/mellanox/mlx4/cmd.c
+++ b/drivers/net/ethernet/mellanox/mlx4/cmd.c
@@ -2792,9 +2792,8 @@ int mlx4_slave_convert_port(struct mlx4_dev *dev, int slave, int port)
{
unsigned n;
struct mlx4_active_ports actv_ports = mlx4_get_active_ports(dev, slave);
- unsigned m = bitmap_weight(actv_ports.ports, dev->caps.num_ports);

- if (port <= 0 || port > m)
+ if (port <= 0 || bitmap_weight_lt(actv_ports.ports, dev->caps.num_ports, port))
return -EINVAL;

n = find_first_bit(actv_ports.ports, dev->caps.num_ports);
@@ -3404,10 +3403,6 @@ int mlx4_vf_set_enable_smi_admin(struct mlx4_dev *dev, int slave, int port,
struct mlx4_priv *priv = mlx4_priv(dev);
struct mlx4_active_ports actv_ports = mlx4_get_active_ports(
&priv->dev, slave);
- int min_port = find_first_bit(actv_ports.ports,
- priv->dev.caps.num_ports) + 1;
- int max_port = min_port - 1 +
- bitmap_weight(actv_ports.ports, priv->dev.caps.num_ports);

if (slave == mlx4_master_func_num(dev))
return 0;
@@ -3417,7 +3412,8 @@ int mlx4_vf_set_enable_smi_admin(struct mlx4_dev *dev, int slave, int port,
enabled < 0 || enabled > 1)
return -EINVAL;

- if (min_port == max_port && dev->caps.num_ports > 1) {
+ if (dev->caps.num_ports > 1 &&
+ bitmap_weight_eq(actv_ports.ports, priv->dev.caps.num_ports, 1)) {
mlx4_info(dev, "SMI access disallowed for single ported VFs\n");
return -EPROTONOSUPPORT;
}
diff --git a/drivers/net/ethernet/mellanox/mlx4/eq.c b/drivers/net/ethernet/mellanox/mlx4/eq.c
index 414e390e6b48..0c09432ff389 100644
--- a/drivers/net/ethernet/mellanox/mlx4/eq.c
+++ b/drivers/net/ethernet/mellanox/mlx4/eq.c
@@ -1435,8 +1435,8 @@ int mlx4_is_eq_shared(struct mlx4_dev *dev, int vector)
if (vector <= 0 || (vector >= dev->caps.num_comp_vectors + 1))
return -EINVAL;

- return !!(bitmap_weight(priv->eq_table.eq[vector].actv_ports.ports,
- dev->caps.num_ports) > 1);
+ return bitmap_weight_gt(priv->eq_table.eq[vector].actv_ports.ports,
+ dev->caps.num_ports, 1);
}
EXPORT_SYMBOL(mlx4_is_eq_shared);

diff --git a/drivers/net/ethernet/mellanox/mlx4/fw.c b/drivers/net/ethernet/mellanox/mlx4/fw.c
index 42c96c9d7fb1..855aae326ccb 100644
--- a/drivers/net/ethernet/mellanox/mlx4/fw.c
+++ b/drivers/net/ethernet/mellanox/mlx4/fw.c
@@ -1300,8 +1300,8 @@ int mlx4_QUERY_DEV_CAP_wrapper(struct mlx4_dev *dev, int slave,
actv_ports = mlx4_get_active_ports(dev, slave);
first_port = find_first_bit(actv_ports.ports, dev->caps.num_ports);
for (slave_port = 0, real_port = first_port;
- real_port < first_port +
- bitmap_weight(actv_ports.ports, dev->caps.num_ports);
+ bitmap_weight_gt(actv_ports.ports, dev->caps.num_ports,
+ real_port - first_port);
++real_port, ++slave_port) {
if (flags & (MLX4_DEV_CAP_FLAG_WOL_PORT1 << real_port))
flags |= MLX4_DEV_CAP_FLAG_WOL_PORT1 << slave_port;
diff --git a/drivers/net/ethernet/mellanox/mlx4/main.c b/drivers/net/ethernet/mellanox/mlx4/main.c
index b187c210d4d6..cfbaa7ac712f 100644
--- a/drivers/net/ethernet/mellanox/mlx4/main.c
+++ b/drivers/net/ethernet/mellanox/mlx4/main.c
@@ -1383,7 +1383,7 @@ static int mlx4_mf_bond(struct mlx4_dev *dev)
dev->persist->num_vfs + 1);

/* only single port vfs are allowed */
- if (bitmap_weight(slaves_port_1_2, dev->persist->num_vfs + 1) > 1) {
+ if (bitmap_weight_gt(slaves_port_1_2, dev->persist->num_vfs + 1, 1)) {
mlx4_warn(dev, "HA mode unsupported for dual ported VFs\n");
return -EINVAL;
}
diff --git a/drivers/perf/thunderx2_pmu.c b/drivers/perf/thunderx2_pmu.c
index 05378c0fd8f3..ebfa66b212c7 100644
--- a/drivers/perf/thunderx2_pmu.c
+++ b/drivers/perf/thunderx2_pmu.c
@@ -623,8 +623,8 @@ static void tx2_uncore_event_start(struct perf_event *event, int flags)
return;

/* Start timer for first event */
- if (bitmap_weight(tx2_pmu->active_counters,
- tx2_pmu->max_counters) == 1) {
+ if (bitmap_weight_eq(tx2_pmu->active_counters,
+ tx2_pmu->max_counters, 1)) {
hrtimer_start(&tx2_pmu->hrtimer,
ns_to_ktime(tx2_pmu->hrtimer_interval),
HRTIMER_MODE_REL_PINNED);
diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index 69d9787d5338..98d878a5ca6b 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -436,7 +436,7 @@ static int tegra_channel_enum_format(struct file *file, void *fh,
if (!IS_ENABLED(CONFIG_VIDEO_TEGRA_TPG))
fmts_bitmap = chan->fmts_bitmap;

- if (f->index >= bitmap_weight(fmts_bitmap, MAX_FORMAT_NUM))
+ if (bitmap_weight_le(fmts_bitmap, MAX_FORMAT_NUM, f->index))
return -EINVAL;

for (i = 0; i < f->index + 1; i++, index++)