The patch titled
Subject: cpumask: replace cpumask_next_* with cpumask_first_* where appropriate
has been added to the -mm tree. Its filename is
cpumask-replace-cpumask_next_-with-cpumask_first_-where-appropriate.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/cpumask-replace-cpumask_next_-with-cpumask_first_-where-appropriate.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/cpumask-replace-cpumask_next_-with-cpumask_first_-where-appropriate.patch
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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Yury Norov <yury.norov@xxxxxxxxx>
Subject: cpumask: replace cpumask_next_* with cpumask_first_* where appropriate
cpumask_first() is a more effective analogue of 'next' version if n == -1
(which means start == 0). This patch replaces 'next' with 'first' where
things look trivial.
There's no cpumask_first_zero() function, so create it.
Link: https://lkml.kernel.org/r/20210814211713.180533-10-yury.norov@xxxxxxxxx
Signed-off-by: Yury Norov <yury.norov@xxxxxxxxx>
Tested-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
Cc: Alexander Lobakin <alobakin@xxxxx>
Cc: Alexey Klimov <aklimov@xxxxxxxxxx>
Cc: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Cc: Dennis Zhou <dennis@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: kernel test robot <lkp@xxxxxxxxx>
Cc: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/powerpc/include/asm/cputhreads.h | 2 +-
block/blk-mq.c | 2 +-
drivers/net/virtio_net.c | 2 +-
drivers/soc/fsl/qbman/bman_portal.c | 2 +-
drivers/soc/fsl/qbman/qman_portal.c | 2 +-
include/linux/cpumask.h | 16 ++++++++++++++++
kernel/time/clocksource.c | 4 ++--
7 files changed, 23 insertions(+), 7 deletions(-)
--- a/arch/powerpc/include/asm/cputhreads.h~cpumask-replace-cpumask_next_-with-cpumask_first_-where-appropriate
+++ a/arch/powerpc/include/asm/cputhreads.h
@@ -52,7 +52,7 @@ static inline cpumask_t cpu_thread_mask_
for (i = 0; i < NR_CPUS; i += threads_per_core) {
cpumask_shift_left(&tmp, &threads_core_mask, i);
if (cpumask_intersects(threads, &tmp)) {
- cpu = cpumask_next_and(-1, &tmp, cpu_online_mask);
+ cpu = cpumask_first_and(&tmp, cpu_online_mask);
if (cpu < nr_cpu_ids)
cpumask_set_cpu(cpu, &res);
}
--- a/block/blk-mq.c~cpumask-replace-cpumask_next_-with-cpumask_first_-where-appropriate
+++ a/block/blk-mq.c
@@ -2544,7 +2544,7 @@ static bool blk_mq_hctx_has_requests(str
static inline bool blk_mq_last_cpu_in_hctx(unsigned int cpu,
struct blk_mq_hw_ctx *hctx)
{
- if (cpumask_next_and(-1, hctx->cpumask, cpu_online_mask) != cpu)
+ if (cpumask_first_and(hctx->cpumask, cpu_online_mask) != cpu)
return false;
if (cpumask_next_and(cpu, hctx->cpumask, cpu_online_mask) < nr_cpu_ids)
return false;
--- a/drivers/net/virtio_net.c~cpumask-replace-cpumask_next_-with-cpumask_first_-where-appropriate
+++ a/drivers/net/virtio_net.c
@@ -2091,7 +2091,7 @@ static void virtnet_set_affinity(struct
stragglers = num_cpu >= vi->curr_queue_pairs ?
num_cpu % vi->curr_queue_pairs :
0;
- cpu = cpumask_next(-1, cpu_online_mask);
+ cpu = cpumask_first(cpu_online_mask);
for (i = 0; i < vi->curr_queue_pairs; i++) {
group_size = stride + (i < stragglers ? 1 : 0);
--- a/drivers/soc/fsl/qbman/bman_portal.c~cpumask-replace-cpumask_next_-with-cpumask_first_-where-appropriate
+++ a/drivers/soc/fsl/qbman/bman_portal.c
@@ -155,7 +155,7 @@ static int bman_portal_probe(struct plat
}
spin_lock(&bman_lock);
- cpu = cpumask_next_zero(-1, &portal_cpus);
+ cpu = cpumask_first_zero(&portal_cpus);
if (cpu >= nr_cpu_ids) {
__bman_portals_probed = 1;
/* unassigned portal, skip init */
--- a/drivers/soc/fsl/qbman/qman_portal.c~cpumask-replace-cpumask_next_-with-cpumask_first_-where-appropriate
+++ a/drivers/soc/fsl/qbman/qman_portal.c
@@ -248,7 +248,7 @@ static int qman_portal_probe(struct plat
pcfg->pools = qm_get_pools_sdqcr();
spin_lock(&qman_lock);
- cpu = cpumask_next_zero(-1, &portal_cpus);
+ cpu = cpumask_first_zero(&portal_cpus);
if (cpu >= nr_cpu_ids) {
__qman_portals_probed = 1;
/* unassigned portal, skip init */
--- a/include/linux/cpumask.h~cpumask-replace-cpumask_next_-with-cpumask_first_-where-appropriate
+++ a/include/linux/cpumask.h
@@ -123,6 +123,11 @@ static inline unsigned int cpumask_first
return 0;
}
+static inline unsigned int cpumask_first_zero(const struct cpumask *srcp)
+{
+ return 0;
+}
+
static inline unsigned int cpumask_first_and(const struct cpumask *srcp1,
const struct cpumask *srcp2)
{
@@ -202,6 +207,17 @@ static inline unsigned int cpumask_first
}
/**
+ * cpumask_first_zero - get the first unset cpu in a cpumask
+ * @srcp: the cpumask pointer
+ *
+ * Returns >= nr_cpu_ids if all cpus are set.
+ */
+static inline unsigned int cpumask_first_zero(const struct cpumask *srcp)
+{
+ return find_first_zero_bit(cpumask_bits(srcp), nr_cpumask_bits);
+}
+
+/**
* cpumask_first_and - return the first cpu from *srcp1 & *srcp2
* @src1p: the first input
* @src2p: the second input
--- a/kernel/time/clocksource.c~cpumask-replace-cpumask_next_-with-cpumask_first_-where-appropriate
+++ a/kernel/time/clocksource.c
@@ -257,7 +257,7 @@ static void clocksource_verify_choose_cp
return;
/* Make sure to select at least one CPU other than the current CPU. */
- cpu = cpumask_next(-1, cpu_online_mask);
+ cpu = cpumask_first(cpu_online_mask);
if (cpu == smp_processor_id())
cpu = cpumask_next(cpu, cpu_online_mask);
if (WARN_ON_ONCE(cpu >= nr_cpu_ids))
@@ -279,7 +279,7 @@ static void clocksource_verify_choose_cp
cpu = prandom_u32() % nr_cpu_ids;
cpu = cpumask_next(cpu - 1, cpu_online_mask);
if (cpu >= nr_cpu_ids)
- cpu = cpumask_next(-1, cpu_online_mask);
+ cpu = cpumask_first(cpu_online_mask);
if (!WARN_ON_ONCE(cpu >= nr_cpu_ids))
cpumask_set_cpu(cpu, &cpus_chosen);
}
_
Patches currently in -mm which might be from yury.norov@xxxxxxxxx are
bitops-protect-find_first_zero_bit-properly.patch
bitops-move-find_bit__le-functions-from-leh-to-findh.patch
include-move-findh-from-asm_generic-to-linux.patch
arch-remove-generic_find_first_bit-entirely.patch
lib-add-find_first_and_bit.patch
cpumask-use-find_first_and_bit.patch
all-replace-find_next_zero_bit-with-find_first_zero_bit-where-appropriate.patch
tools-sync-tools-bitmap-with-mother-linux.patch
cpumask-replace-cpumask_next_-with-cpumask_first_-where-appropriate.patch
include-linux-move-for_each_bit-macros-from-bitopsh-to-findh.patch
find-micro-optimize-for_each_setclear_bit.patch
replace-for_each__bit_from-with-for_each__bit-where-appropriate.patch
mm-percpu-micro-optimize-pcpu_is_populated.patch
bitmap-unify-find_bit-operations.patch
lib-bitmap-add-performance-test-for-bitmap_print_to_pagebuf.patch
vsprintf-rework-bitmap_list_string.patch
