From 414cbd1e3d14ec0e60666a0fb9d8ae2d77eb7c63 Mon Sep 17 00:00:00 2001 From: Sebastian Ott Date: Wed, 27 Feb 2019 13:56:08 +0100 Subject: [PATCH] s390/airq: provide cacheline aligned ivs Provide the ability to create cachesize aligned interrupt vectors. These will be used for per-CPU interrupt vectors. Signed-off-by: Sebastian Ott Signed-off-by: Martin Schwidefsky --- arch/s390/include/asm/airq.h | 10 +++++---- drivers/s390/cio/airq.c | 39 +++++++++++++++++++++++++++++++----- 2 files changed, 40 insertions(+), 9 deletions(-) diff --git a/arch/s390/include/asm/airq.h b/arch/s390/include/asm/airq.h index 91e78df365c7..c10d2ee2dfda 100644 --- a/arch/s390/include/asm/airq.h +++ b/arch/s390/include/asm/airq.h @@ -35,13 +35,15 @@ struct airq_iv { unsigned int *data; /* 32 bit value associated with each bit */ unsigned long bits; /* Number of bits in the vector */ unsigned long end; /* Number of highest allocated bit + 1 */ + unsigned long flags; /* Allocation flags */ spinlock_t lock; /* Lock to protect alloc & free */ }; -#define AIRQ_IV_ALLOC 1 /* Use an allocation bit mask */ -#define AIRQ_IV_BITLOCK 2 /* Allocate the lock bit mask */ -#define AIRQ_IV_PTR 4 /* Allocate the ptr array */ -#define AIRQ_IV_DATA 8 /* Allocate the data array */ +#define AIRQ_IV_ALLOC 1 /* Use an allocation bit mask */ +#define AIRQ_IV_BITLOCK 2 /* Allocate the lock bit mask */ +#define AIRQ_IV_PTR 4 /* Allocate the ptr array */ +#define AIRQ_IV_DATA 8 /* Allocate the data array */ +#define AIRQ_IV_CACHELINE 16 /* Cacheline alignment for the vector */ struct airq_iv *airq_iv_create(unsigned long bits, unsigned long flags); void airq_iv_release(struct airq_iv *iv); diff --git a/drivers/s390/cio/airq.c b/drivers/s390/cio/airq.c index e045e79f061c..4534afc63591 100644 --- a/drivers/s390/cio/airq.c +++ b/drivers/s390/cio/airq.c @@ -27,6 +27,8 @@ static DEFINE_SPINLOCK(airq_lists_lock); static struct hlist_head airq_lists[MAX_ISC+1]; +static struct kmem_cache *airq_iv_cache; + /** * register_adapter_interrupt() - register adapter interrupt handler * @airq: pointer to adapter interrupt descriptor @@ -129,10 +131,21 @@ struct airq_iv *airq_iv_create(unsigned long bits, unsigned long flags) if (!iv) goto out; iv->bits = bits; + iv->flags = flags; size = BITS_TO_LONGS(bits) * sizeof(unsigned long); - iv->vector = kzalloc(size, GFP_KERNEL); - if (!iv->vector) - goto out_free; + + if (flags & AIRQ_IV_CACHELINE) { + if ((cache_line_size() * BITS_PER_BYTE) < bits) + goto out_free; + + iv->vector = kmem_cache_zalloc(airq_iv_cache, GFP_KERNEL); + if (!iv->vector) + goto out_free; + } else { + iv->vector = kzalloc(size, GFP_KERNEL); + if (!iv->vector) + goto out_free; + } if (flags & AIRQ_IV_ALLOC) { iv->avail = kmalloc(size, GFP_KERNEL); if (!iv->avail) @@ -165,7 +178,10 @@ out_free: kfree(iv->ptr); kfree(iv->bitlock); kfree(iv->avail); - kfree(iv->vector); + if (iv->flags & AIRQ_IV_CACHELINE) + kmem_cache_free(airq_iv_cache, iv->vector); + else + kfree(iv->vector); kfree(iv); out: return NULL; @@ -181,7 +197,10 @@ void airq_iv_release(struct airq_iv *iv) kfree(iv->data); kfree(iv->ptr); kfree(iv->bitlock); - kfree(iv->vector); + if (iv->flags & AIRQ_IV_CACHELINE) + kmem_cache_free(airq_iv_cache, iv->vector); + else + kfree(iv->vector); kfree(iv->avail); kfree(iv); } @@ -275,3 +294,13 @@ unsigned long airq_iv_scan(struct airq_iv *iv, unsigned long start, return bit; } EXPORT_SYMBOL(airq_iv_scan); + +static int __init airq_init(void) +{ + airq_iv_cache = kmem_cache_create("airq_iv_cache", cache_line_size(), + cache_line_size(), 0, NULL); + if (!airq_iv_cache) + return -ENOMEM; + return 0; +} +subsys_initcall(airq_init);