remove unused flag KMC_KMEM

include/os/linux/spl/sys/kmem_cache.h

@@ -41,7 +41,6 @@ typedef enum kmc_bit {
 	KMC_BIT_NOMAGAZINE	= 2,	/* XXX: Unsupported */
 	KMC_BIT_NOHASH		= 3,	/* XXX: Unsupported */
 	KMC_BIT_QCACHE		= 4,	/* XXX: Unsupported */
-	KMC_BIT_KMEM		= 5,	/* Use kmem cache */
 	KMC_BIT_VMEM		= 6,	/* Use vmem cache */
 	KMC_BIT_KVMEM		= 7,	/* Use kvmalloc linux allocator  */
 	KMC_BIT_SLAB		= 8,	/* Use Linux slab cache */
@@ -69,7 +68,6 @@ typedef enum kmem_cbrc {
 #define	KMC_NOMAGAZINE		(1 << KMC_BIT_NOMAGAZINE)
 #define	KMC_NOHASH		(1 << KMC_BIT_NOHASH)
 #define	KMC_QCACHE		(1 << KMC_BIT_QCACHE)
-#define	KMC_KMEM		(1 << KMC_BIT_KMEM)
 #define	KMC_VMEM		(1 << KMC_BIT_VMEM)
 #define	KMC_KVMEM		(1 << KMC_BIT_KVMEM)
 #define	KMC_SLAB		(1 << KMC_BIT_SLAB)

include/sys/zfs_context.h

@@ -402,7 +402,6 @@ void procfs_list_add(procfs_list_t *procfs_list, void *p);
 #define	KM_NOSLEEP		UMEM_DEFAULT
 #define	KM_NORMALPRI		0	/* not needed with UMEM_DEFAULT */
 #define	KMC_NODEBUG		UMC_NODEBUG
-#define	KMC_KMEM		0x0
 #define	KMC_VMEM		0x0
 #define	KMC_KVMEM		0x0
 #define	kmem_alloc(_s, _f)	umem_alloc(_s, _f)

module/os/linux/spl/spl-kmem-cache.c

@@ -112,17 +112,6 @@ module_param(spl_kmem_cache_slab_limit, uint, 0644);
 MODULE_PARM_DESC(spl_kmem_cache_slab_limit,
 	"Objects less than N bytes use the Linux slab");
 
-/*
- * This value defaults to a threshold designed to avoid allocations which
- * have been deemed costly by the kernel.
- */
-unsigned int spl_kmem_cache_kmem_limit =
-	((1 << (PAGE_ALLOC_COSTLY_ORDER - 1)) * PAGE_SIZE) /
-	SPL_KMEM_CACHE_OBJ_PER_SLAB;
-module_param(spl_kmem_cache_kmem_limit, uint, 0644);
-MODULE_PARM_DESC(spl_kmem_cache_kmem_limit,
-	"Objects less than N bytes use the kmalloc");
-
 /*
  * The number of threads available to allocate new slabs for caches.  This
  * should not need to be tuned but it is available for performance analysis.
@@ -177,12 +166,7 @@ kv_alloc(spl_kmem_cache_t *skc, int size, int flags)
 	gfp_t lflags = kmem_flags_convert(flags);
 	void *ptr;
 
-	if (skc->skc_flags & KMC_KMEM) {
-		ASSERT(ISP2(size));
-		ptr = (void *)__get_free_pages(lflags, get_order(size));
-	} else {
-		ptr = spl_vmalloc(size, lflags | __GFP_HIGHMEM);
-	}
+	ptr = spl_vmalloc(size, lflags | __GFP_HIGHMEM);
 
 	/* Resulting allocated memory will be page aligned */
 	ASSERT(IS_P2ALIGNED(ptr, PAGE_SIZE));
@@ -205,12 +189,7 @@ kv_free(spl_kmem_cache_t *skc, void *ptr, int size)
 	if (current->reclaim_state)
 		current->reclaim_state->reclaimed_slab += size >> PAGE_SHIFT;
 
-	if (skc->skc_flags & KMC_KMEM) {
-		ASSERT(ISP2(size));
-		free_pages((unsigned long)ptr, get_order(size));
-	} else {
-		vfree(ptr);
-	}
+	vfree(ptr);
 }
 
 /*
@@ -606,28 +585,12 @@ spl_slab_size(spl_kmem_cache_t *skc, uint32_t *objs, uint32_t *size)
 	if (skc->skc_flags & KMC_OFFSLAB) {
 		tgt_objs = spl_kmem_cache_obj_per_slab;
 		tgt_size = P2ROUNDUP(sizeof (spl_kmem_slab_t), PAGE_SIZE);
-
-		if ((skc->skc_flags & KMC_KMEM) &&
-		    (spl_obj_size(skc) > (SPL_MAX_ORDER_NR_PAGES * PAGE_SIZE)))
-			return (-ENOSPC);
 	} else {
 		sks_size = spl_sks_size(skc);
 		obj_size = spl_obj_size(skc);
 		max_size = (spl_kmem_cache_max_size * 1024 * 1024);
 		tgt_size = (spl_kmem_cache_obj_per_slab * obj_size + sks_size);
 
-		/*
-		 * KMC_KMEM slabs are allocated by __get_free_pages() which
-		 * rounds up to the nearest order.  Knowing this the size
-		 * should be rounded up to the next power of two with a hard
-		 * maximum defined by the maximum allowed allocation order.
-		 */
-		if (skc->skc_flags & KMC_KMEM) {
-			max_size = SPL_MAX_ORDER_NR_PAGES * PAGE_SIZE;
-			tgt_size = MIN(max_size,
-			    PAGE_SIZE * (1 << MAX(get_order(tgt_size) - 1, 1)));
-		}
-
 		if (tgt_size <= max_size) {
 			tgt_objs = (tgt_size - sks_size) / obj_size;
 		} else {
@@ -770,7 +733,6 @@ spl_magazine_destroy(spl_kmem_cache_t *skc)
  * priv		cache private data for ctor/dtor/reclaim
  * vmp		unused must be NULL
  * flags
- *	KMC_KMEM	Force SPL kmem backed cache
  *	KMC_VMEM        Force SPL vmem backed cache
  *	KMC_KVMEM       Force kvmem backed cache
  *	KMC_SLAB        Force Linux slab backed cache
@@ -865,21 +827,14 @@ spl_kmem_cache_create(char *name, size_t size, size_t align,
 	 * linuxslab) then select a cache type based on the object size
 	 * and default tunables.
 	 */
-	if (!(skc->skc_flags & (KMC_KMEM | KMC_VMEM | KMC_SLAB | KMC_KVMEM))) {
+	if (!(skc->skc_flags & (KMC_VMEM | KMC_SLAB | KMC_KVMEM))) {
 		if (spl_kmem_cache_slab_limit &&
 		    size <= (size_t)spl_kmem_cache_slab_limit) {
 			/*
 			 * Objects smaller than spl_kmem_cache_slab_limit can
 			 * use the Linux slab for better space-efficiency.
 			 */
 			skc->skc_flags |= KMC_SLAB;
-		} else if (spl_obj_size(skc) <= spl_kmem_cache_kmem_limit) {
-			/*
-			 * Small objects, less than spl_kmem_cache_kmem_limit
-			 * per object should use kmem because their slabs are
-			 * small.
-			 */
-			skc->skc_flags |= KMC_KMEM;
 		} else {
 			/*
 			 * All other objects are considered large and are
@@ -892,7 +847,7 @@ spl_kmem_cache_create(char *name, size_t size, size_t align,
 	/*
 	 * Given the type of slab allocate the required resources.
 	 */
-	if (skc->skc_flags & (KMC_KMEM | KMC_VMEM | KMC_KVMEM)) {
+	if (skc->skc_flags & (KMC_VMEM | KMC_KVMEM)) {
 		rc = spl_slab_size(skc,
 		    &skc->skc_slab_objs, &skc->skc_slab_size);
 		if (rc)
@@ -971,7 +926,7 @@ spl_kmem_cache_destroy(spl_kmem_cache_t *skc)
 	taskqid_t id;
 
 	ASSERT(skc->skc_magic == SKC_MAGIC);
-	ASSERT(skc->skc_flags & (KMC_KMEM | KMC_VMEM | KMC_KVMEM | KMC_SLAB));
+	ASSERT(skc->skc_flags & (KMC_VMEM | KMC_KVMEM | KMC_SLAB));
 
 	down_write(&spl_kmem_cache_sem);
 	list_del_init(&skc->skc_list);
@@ -993,7 +948,7 @@ spl_kmem_cache_destroy(spl_kmem_cache_t *skc)
 	 */
 	wait_event(wq, atomic_read(&skc->skc_ref) == 0);
 
-	if (skc->skc_flags & (KMC_KMEM | KMC_VMEM | KMC_KVMEM)) {
+	if (skc->skc_flags & (KMC_VMEM | KMC_KVMEM)) {
 		spl_magazine_destroy(skc);
 		spl_slab_reclaim(skc);
 	} else {

module/os/linux/spl/spl-proc.c

@@ -631,33 +631,6 @@ static struct ctl_table spl_kmem_table[] = {
 		.proc_handler	= &proc_doulongvec_minmax,
 	},
 #endif /* DEBUG_KMEM */
-	{
-		.procname	= "slab_kmem_total",
-		.data		= (void *)(KMC_KMEM | KMC_TOTAL),
-		.maxlen		= sizeof (unsigned long),
-		.extra1		= &table_min,
-		.extra2		= &table_max,
-		.mode		= 0444,
-		.proc_handler = &proc_doslab,
-	},
-	{
-		.procname	= "slab_kmem_alloc",
-		.data		= (void *)(KMC_KMEM | KMC_ALLOC),
-		.maxlen		= sizeof (unsigned long),
-		.extra1		= &table_min,
-		.extra2		= &table_max,
-		.mode		= 0444,
-		.proc_handler	= &proc_doslab,
-	},
-	{
-		.procname	= "slab_kmem_max",
-		.data		= (void *)(KMC_KMEM | KMC_MAX),
-		.maxlen		= sizeof (unsigned long),
-		.extra1		= &table_min,
-		.extra2		= &table_max,
-		.mode		= 0444,
-		.proc_handler	= &proc_doslab,
-	},
 	{
 		.procname	= "slab_vmem_total",
 		.data		= (void *)(KMC_VMEM | KMC_TOTAL),