diff options
Diffstat (limited to 'module/spl/spl-vmem.c')
| -rw-r--r-- | module/spl/spl-vmem.c | 34 |
1 files changed, 30 insertions, 4 deletions
diff --git a/module/spl/spl-vmem.c b/module/spl/spl-vmem.c index e177988a7..dd10607dc 100644 --- a/module/spl/spl-vmem.c +++ b/module/spl/spl-vmem.c @@ -24,6 +24,7 @@ #include <sys/debug.h> #include <sys/vmem.h> +#include <sys/kmem_cache.h> #include <linux/mm_compat.h> #include <linux/module.h> @@ -36,14 +37,39 @@ EXPORT_SYMBOL(zio_alloc_arena); vmem_t *zio_arena = NULL; EXPORT_SYMBOL(zio_arena); +#define VMEM_FLOOR_SIZE (4 * 1024 * 1024) /* 4MB floor */ + +/* + * Return approximate virtual memory usage based on these assumptions: + * + * 1) The major SPL consumer of virtual memory is the kmem cache. + * 2) Memory allocated with vmem_alloc() is short lived and can be ignored. + * 3) Allow a 4MB floor as a generous pad given normal consumption. + * 4) The spl_kmem_cache_sem only contends with cache create/destroy. + */ size_t vmem_size(vmem_t *vmp, int typemask) { - ASSERT3P(vmp, ==, NULL); - ASSERT3S(typemask & VMEM_ALLOC, ==, VMEM_ALLOC); - ASSERT3S(typemask & VMEM_FREE, ==, VMEM_FREE); + spl_kmem_cache_t *skc; + size_t alloc = VMEM_FLOOR_SIZE; + + if ((typemask & VMEM_ALLOC) && (typemask & VMEM_FREE)) + return (VMALLOC_TOTAL); + + + down_read(&spl_kmem_cache_sem); + list_for_each_entry(skc, &spl_kmem_cache_list, skc_list) { + if (skc->skc_flags & KMC_VMEM) + alloc += skc->skc_slab_size * skc->skc_slab_total; + } + up_read(&spl_kmem_cache_sem); - return (VMALLOC_TOTAL); + if (typemask & VMEM_ALLOC) + return (MIN(alloc, VMALLOC_TOTAL)); + else if (typemask & VMEM_FREE) + return (MAX(VMALLOC_TOTAL - alloc, 0)); + else + return (0); } EXPORT_SYMBOL(vmem_size); |