Commit 9b130ad5 authored by Alexey Dobriyan's avatar Alexey Dobriyan Committed by Linus Torvalds
Browse files

treewide: make "nr_cpu_ids" unsigned

First, number of CPUs can't be negative number.

Second, different signnnedness leads to suboptimal code in the following
cases:

1)
	kmalloc(nr_cpu_ids * sizeof(X));

"int" has to be sign extended to size_t.

2)
	while (loff_t *pos < nr_cpu_ids)

MOVSXD is 1 byte longed than the same MOV.

Other cases exist as well. Basically compiler is told that nr_cpu_ids
can't be negative which can't be deduced if it is "int".

Code savings on allyesconfig kernel: -3KB

	add/remove: 0/0 grow/shrink: 25/264 up/down: 261/-3631 (-3370)
	function                                     old     new   delta
	coretemp_cpu_online                          450     512     +62
	rcu_init_one                                1234    1272     +38
	pci_device_probe                             374     399     +25

				...

	pgdat_reclaimable_pages                      628     556     -72
	select_fallback_rq                           446     369     -77
	task_numa_find_cpu                          1923    1807    -116

Link: http://lkml.kernel.org/r/20170819114959.GA30580@avx2

Signed-off-by: default avatarAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent ac036f95
......@@ -690,7 +690,7 @@ void __init smp_init_cpus(void)
acpi_parse_gic_cpu_interface, 0);
if (cpu_count > nr_cpu_ids)
pr_warn("Number of cores (%d) exceeds configured maximum of %d - clipping\n",
pr_warn("Number of cores (%d) exceeds configured maximum of %u - clipping\n",
cpu_count, nr_cpu_ids);
if (!bootcpu_valid) {
......
......@@ -224,7 +224,7 @@ void __init allocate_pacas(void)
paca = __va(memblock_alloc_base(paca_size, PAGE_SIZE, limit));
memset(paca, 0, paca_size);
printk(KERN_DEBUG "Allocated %u bytes for %d pacas at %p\n",
printk(KERN_DEBUG "Allocated %u bytes for %u pacas at %p\n",
paca_size, nr_cpu_ids, paca);
allocate_lppacas(nr_cpu_ids, limit);
......
......@@ -551,7 +551,7 @@ void __init smp_setup_cpu_maps(void)
if (maxcpus > nr_cpu_ids) {
printk(KERN_WARNING
"Partition configured for %d cpus, "
"operating system maximum is %d.\n",
"operating system maximum is %u.\n",
maxcpus, nr_cpu_ids);
maxcpus = nr_cpu_ids;
} else
......
......@@ -511,13 +511,13 @@ static bool xive_parse_provisioning(struct device_node *np)
static void xive_native_setup_pools(void)
{
/* Allocate a pool big enough */
pr_debug("XIVE: Allocating VP block for pool size %d\n", nr_cpu_ids);
pr_debug("XIVE: Allocating VP block for pool size %u\n", nr_cpu_ids);
xive_pool_vps = xive_native_alloc_vp_block(nr_cpu_ids);
if (WARN_ON(xive_pool_vps == XIVE_INVALID_VP))
pr_err("XIVE: Failed to allocate pool VP, KVM might not function\n");
pr_debug("XIVE: Pool VPs allocated at 0x%x for %d max CPUs\n",
pr_debug("XIVE: Pool VPs allocated at 0x%x for %u max CPUs\n",
xive_pool_vps, nr_cpu_ids);
}
......
......@@ -1200,7 +1200,7 @@ static void __init validate_hv(void)
* We use a struct cpumask for this, so it must be big enough.
*/
if ((smp_height * smp_width) > nr_cpu_ids)
early_panic("Hypervisor %d x %d grid too big for Linux NR_CPUS %d\n",
early_panic("Hypervisor %d x %d grid too big for Linux NR_CPUS %u\n",
smp_height, smp_width, nr_cpu_ids);
#endif
......
......@@ -2097,7 +2097,7 @@ static int allocate_logical_cpuid(int apicid)
/* Allocate a new cpuid. */
if (nr_logical_cpuids >= nr_cpu_ids) {
WARN_ONCE(1, "APIC: NR_CPUS/possible_cpus limit of %i reached. "
WARN_ONCE(1, "APIC: NR_CPUS/possible_cpus limit of %u reached. "
"Processor %d/0x%x and the rest are ignored.\n",
nr_cpu_ids, nr_logical_cpuids, apicid);
return -EINVAL;
......
......@@ -168,7 +168,7 @@ void __init setup_per_cpu_areas(void)
unsigned long delta;
int rc;
pr_info("NR_CPUS:%d nr_cpumask_bits:%d nr_cpu_ids:%d nr_node_ids:%d\n",
pr_info("NR_CPUS:%d nr_cpumask_bits:%d nr_cpu_ids:%u nr_node_ids:%d\n",
NR_CPUS, nr_cpumask_bits, nr_cpu_ids, nr_node_ids);
/*
......
......@@ -1461,7 +1461,7 @@ __init void prefill_possible_map(void)
/* nr_cpu_ids could be reduced via nr_cpus= */
if (possible > nr_cpu_ids) {
pr_warn("%d Processors exceeds NR_CPUS limit of %d\n",
pr_warn("%d Processors exceeds NR_CPUS limit of %u\n",
possible, nr_cpu_ids);
possible = nr_cpu_ids;
}
......
......@@ -256,9 +256,9 @@ static ssize_t print_cpus_offline(struct device *dev,
buf[n++] = ',';
if (nr_cpu_ids == total_cpus-1)
n += snprintf(&buf[n], len - n, "%d", nr_cpu_ids);
n += snprintf(&buf[n], len - n, "%u", nr_cpu_ids);
else
n += snprintf(&buf[n], len - n, "%d-%d",
n += snprintf(&buf[n], len - n, "%u-%d",
nr_cpu_ids, total_cpus-1);
}
......
......@@ -5465,7 +5465,7 @@ static int sdebug_driver_probe(struct device * dev)
return error;
}
if (submit_queues > nr_cpu_ids) {
pr_warn("%s: trim submit_queues (was %d) to nr_cpu_ids=%d\n",
pr_warn("%s: trim submit_queues (was %d) to nr_cpu_ids=%u\n",
my_name, submit_queues, nr_cpu_ids);
submit_queues = nr_cpu_ids;
}
......
......@@ -32,15 +32,15 @@ typedef struct cpumask { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t;
#define cpumask_pr_args(maskp) nr_cpu_ids, cpumask_bits(maskp)
#if NR_CPUS == 1
#define nr_cpu_ids 1
#define nr_cpu_ids 1U
#else
extern int nr_cpu_ids;
extern unsigned int nr_cpu_ids;
#endif
#ifdef CONFIG_CPUMASK_OFFSTACK
/* Assuming NR_CPUS is huge, a runtime limit is more efficient. Also,
* not all bits may be allocated. */
#define nr_cpumask_bits ((unsigned int)nr_cpu_ids)
#define nr_cpumask_bits nr_cpu_ids
#else
#define nr_cpumask_bits ((unsigned int)NR_CPUS)
#endif
......
......@@ -4091,7 +4091,7 @@ static void __init rcu_init_geometry(void)
if (rcu_fanout_leaf == RCU_FANOUT_LEAF &&
nr_cpu_ids == NR_CPUS)
return;
pr_info("RCU: Adjusting geometry for rcu_fanout_leaf=%d, nr_cpu_ids=%d\n",
pr_info("RCU: Adjusting geometry for rcu_fanout_leaf=%d, nr_cpu_ids=%u\n",
rcu_fanout_leaf, nr_cpu_ids);
/*
......
......@@ -89,7 +89,7 @@ static void __init rcu_bootup_announce_oddness(void)
if (rcu_fanout_leaf != RCU_FANOUT_LEAF)
pr_info("\tBoot-time adjustment of leaf fanout to %d.\n", rcu_fanout_leaf);
if (nr_cpu_ids != NR_CPUS)
pr_info("\tRCU restricting CPUs from NR_CPUS=%d to nr_cpu_ids=%d.\n", NR_CPUS, nr_cpu_ids);
pr_info("\tRCU restricting CPUs from NR_CPUS=%d to nr_cpu_ids=%u.\n", NR_CPUS, nr_cpu_ids);
#ifdef CONFIG_RCU_BOOST
pr_info("\tRCU priority boosting: priority %d delay %d ms.\n", kthread_prio, CONFIG_RCU_BOOST_DELAY);
#endif
......
......@@ -473,7 +473,7 @@ static int __init isolated_cpu_setup(char *str)
alloc_bootmem_cpumask_var(&cpu_isolated_map);
ret = cpulist_parse(str, cpu_isolated_map);
if (ret) {
pr_err("sched: Error, all isolcpus= values must be between 0 and %d\n", nr_cpu_ids);
pr_err("sched: Error, all isolcpus= values must be between 0 and %u\n", nr_cpu_ids);
return 0;
}
return 1;
......
......@@ -550,7 +550,7 @@ static int __init maxcpus(char *str)
early_param("maxcpus", maxcpus);
/* Setup number of possible processor ids */
int nr_cpu_ids __read_mostly = NR_CPUS;
unsigned int nr_cpu_ids __read_mostly = NR_CPUS;
EXPORT_SYMBOL(nr_cpu_ids);
/* An arch may set nr_cpu_ids earlier if needed, so this would be redundant */
......
......@@ -1543,7 +1543,7 @@ fs_initcall(init_graph_tracefs);
static __init int init_graph_trace(void)
{
max_bytes_for_cpu = snprintf(NULL, 0, "%d", nr_cpu_ids - 1);
max_bytes_for_cpu = snprintf(NULL, 0, "%u", nr_cpu_ids - 1);
if (!register_trace_event(&graph_trace_entry_event)) {
pr_warn("Warning: could not register graph trace events\n");
......
......@@ -4232,7 +4232,7 @@ void __init kmem_cache_init(void)
cpuhp_setup_state_nocalls(CPUHP_SLUB_DEAD, "slub:dead", NULL,
slub_cpu_dead);
pr_info("SLUB: HWalign=%d, Order=%d-%d, MinObjects=%d, CPUs=%d, Nodes=%d\n",
pr_info("SLUB: HWalign=%d, Order=%d-%d, MinObjects=%d, CPUs=%u, Nodes=%d\n",
cache_line_size(),
slub_min_order, slub_max_order, slub_min_objects,
nr_cpu_ids, nr_node_ids);
......
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