summaryrefslogtreecommitdiffstats
path: root/kernel/irq
diff options
context:
space:
mode:
authorBjörn Töpel <bjorn@rivosinc.com>2024-02-22 15:09:58 +0530
committerThomas Gleixner <tglx@linutronix.de>2024-02-23 10:18:44 +0100
commit5b98d210ac1e4eb35abfbd940df50dec10ae81e1 (patch)
tree65242661f0df6215db299588a6ad1b94332d1892 /kernel/irq
parent3c46fc5b5507be1f4aa144a1fbd83b0ccba04cc6 (diff)
downloadlinux-5b98d210ac1e4eb35abfbd940df50dec10ae81e1.tar.gz
linux-5b98d210ac1e4eb35abfbd940df50dec10ae81e1.tar.bz2
linux-5b98d210ac1e4eb35abfbd940df50dec10ae81e1.zip
genirq/matrix: Dynamic bitmap allocation
A future user of the matrix allocator, does not know the size of the matrix bitmaps at compile time. To avoid wasting memory on unnecessary large bitmaps, size the bitmap at matrix allocation time. Signed-off-by: Björn Töpel <bjorn@rivosinc.com> Signed-off-by: Anup Patel <apatel@ventanamicro.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20240222094006.1030709-11-apatel@ventanamicro.com
Diffstat (limited to 'kernel/irq')
-rw-r--r--kernel/irq/matrix.c28
1 files changed, 17 insertions, 11 deletions
diff --git a/kernel/irq/matrix.c b/kernel/irq/matrix.c
index 75d0ae490e29..8f222d1cccec 100644
--- a/kernel/irq/matrix.c
+++ b/kernel/irq/matrix.c
@@ -8,8 +8,6 @@
#include <linux/cpu.h>
#include <linux/irq.h>
-#define IRQ_MATRIX_SIZE (BITS_TO_LONGS(IRQ_MATRIX_BITS))
-
struct cpumap {
unsigned int available;
unsigned int allocated;
@@ -17,8 +15,8 @@ struct cpumap {
unsigned int managed_allocated;
bool initialized;
bool online;
- unsigned long alloc_map[IRQ_MATRIX_SIZE];
- unsigned long managed_map[IRQ_MATRIX_SIZE];
+ unsigned long *managed_map;
+ unsigned long alloc_map[];
};
struct irq_matrix {
@@ -32,8 +30,8 @@ struct irq_matrix {
unsigned int total_allocated;
unsigned int online_maps;
struct cpumap __percpu *maps;
- unsigned long scratch_map[IRQ_MATRIX_SIZE];
- unsigned long system_map[IRQ_MATRIX_SIZE];
+ unsigned long *system_map;
+ unsigned long scratch_map[];
};
#define CREATE_TRACE_POINTS
@@ -50,24 +48,32 @@ __init struct irq_matrix *irq_alloc_matrix(unsigned int matrix_bits,
unsigned int alloc_start,
unsigned int alloc_end)
{
+ unsigned int cpu, matrix_size = BITS_TO_LONGS(matrix_bits);
struct irq_matrix *m;
- if (matrix_bits > IRQ_MATRIX_BITS)
- return NULL;
-
- m = kzalloc(sizeof(*m), GFP_KERNEL);
+ m = kzalloc(struct_size(m, scratch_map, matrix_size * 2), GFP_KERNEL);
if (!m)
return NULL;
+ m->system_map = &m->scratch_map[matrix_size];
+
m->matrix_bits = matrix_bits;
m->alloc_start = alloc_start;
m->alloc_end = alloc_end;
m->alloc_size = alloc_end - alloc_start;
- m->maps = alloc_percpu(*m->maps);
+ m->maps = __alloc_percpu(struct_size(m->maps, alloc_map, matrix_size * 2),
+ __alignof__(*m->maps));
if (!m->maps) {
kfree(m);
return NULL;
}
+
+ for_each_possible_cpu(cpu) {
+ struct cpumap *cm = per_cpu_ptr(m->maps, cpu);
+
+ cm->managed_map = &cm->alloc_map[matrix_size];
+ }
+
return m;
}