From 2264f5132fe45571139727ebdeb78696b35d1506 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Mon, 4 Dec 2017 00:11:48 -0500 Subject: xarray: Add xas_create_range This hopefully temporary function is useful for users who have not yet been converted to multi-index entries. Signed-off-by: Matthew Wilcox --- lib/test_xarray.c | 119 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ lib/xarray.c | 50 +++++++++++++++++++++++ 2 files changed, 169 insertions(+) (limited to 'lib') diff --git a/lib/test_xarray.c b/lib/test_xarray.c index 8eba3de1baea..703370015d10 100644 --- a/lib/test_xarray.c +++ b/lib/test_xarray.c @@ -646,6 +646,124 @@ static noinline void check_move(struct xarray *xa) check_move_small(xa, (1UL << i) - 1); } +static noinline void xa_store_many_order(struct xarray *xa, + unsigned long index, unsigned order) +{ + XA_STATE_ORDER(xas, xa, index, order); + unsigned int i = 0; + + do { + xas_lock(&xas); + XA_BUG_ON(xa, xas_find_conflict(&xas)); + xas_create_range(&xas); + if (xas_error(&xas)) + goto unlock; + for (i = 0; i < (1U << order); i++) { + XA_BUG_ON(xa, xas_store(&xas, xa_mk_value(index + i))); + xas_next(&xas); + } +unlock: + xas_unlock(&xas); + } while (xas_nomem(&xas, GFP_KERNEL)); + + XA_BUG_ON(xa, xas_error(&xas)); +} + +static noinline void check_create_range_1(struct xarray *xa, + unsigned long index, unsigned order) +{ + unsigned long i; + + xa_store_many_order(xa, index, order); + for (i = index; i < index + (1UL << order); i++) + xa_erase_index(xa, i); + XA_BUG_ON(xa, !xa_empty(xa)); +} + +static noinline void check_create_range_2(struct xarray *xa, unsigned order) +{ + unsigned long i; + unsigned long nr = 1UL << order; + + for (i = 0; i < nr * nr; i += nr) + xa_store_many_order(xa, i, order); + for (i = 0; i < nr * nr; i++) + xa_erase_index(xa, i); + XA_BUG_ON(xa, !xa_empty(xa)); +} + +static noinline void check_create_range_3(void) +{ + XA_STATE(xas, NULL, 0); + xas_set_err(&xas, -EEXIST); + xas_create_range(&xas); + XA_BUG_ON(NULL, xas_error(&xas) != -EEXIST); +} + +static noinline void check_create_range_4(struct xarray *xa, + unsigned long index, unsigned order) +{ + XA_STATE_ORDER(xas, xa, index, order); + unsigned long base = xas.xa_index; + unsigned long i = 0; + + xa_store_index(xa, index, GFP_KERNEL); + do { + xas_lock(&xas); + xas_create_range(&xas); + if (xas_error(&xas)) + goto unlock; + for (i = 0; i < (1UL << order); i++) { + void *old = xas_store(&xas, xa_mk_value(base + i)); + if (xas.xa_index == index) + XA_BUG_ON(xa, old != xa_mk_value(base + i)); + else + XA_BUG_ON(xa, old != NULL); + xas_next(&xas); + } +unlock: + xas_unlock(&xas); + } while (xas_nomem(&xas, GFP_KERNEL)); + + XA_BUG_ON(xa, xas_error(&xas)); + + for (i = base; i < base + (1UL << order); i++) + xa_erase_index(xa, i); + XA_BUG_ON(xa, !xa_empty(xa)); +} + +static noinline void check_create_range(struct xarray *xa) +{ + unsigned int order; + unsigned int max_order = IS_ENABLED(CONFIG_XARRAY_MULTI) ? 12 : 1; + + for (order = 0; order < max_order; order++) { + check_create_range_1(xa, 0, order); + check_create_range_1(xa, 1U << order, order); + check_create_range_1(xa, 2U << order, order); + check_create_range_1(xa, 3U << order, order); + check_create_range_1(xa, 1U << 24, order); + if (order < 10) + check_create_range_2(xa, order); + + check_create_range_4(xa, 0, order); + check_create_range_4(xa, 1U << order, order); + check_create_range_4(xa, 2U << order, order); + check_create_range_4(xa, 3U << order, order); + check_create_range_4(xa, 1U << 24, order); + + check_create_range_4(xa, 1, order); + check_create_range_4(xa, (1U << order) + 1, order); + check_create_range_4(xa, (2U << order) + 1, order); + check_create_range_4(xa, (2U << order) - 1, order); + check_create_range_4(xa, (3U << order) + 1, order); + check_create_range_4(xa, (3U << order) - 1, order); + check_create_range_4(xa, (1U << 24) + 1, order); + } + + check_create_range_3(); +} + static noinline void check_destroy(struct xarray *xa) { unsigned long index; @@ -694,6 +812,7 @@ static int xarray_checks(void) check_find(&array); check_destroy(&array); check_move(&array); + check_create_range(&array); check_store_iter(&array); printk("XArray: %u of %u tests passed\n", tests_passed, tests_run); diff --git a/lib/xarray.c b/lib/xarray.c index 41f8ebc651f5..ff37516fe832 100644 --- a/lib/xarray.c +++ b/lib/xarray.c @@ -637,6 +637,56 @@ static void *xas_create(struct xa_state *xas) return entry; } +/** + * xas_create_range() - Ensure that stores to this range will succeed + * @xas: XArray operation state. + * + * Creates all of the slots in the range covered by @xas. Sets @xas to + * create single-index entries and positions it at the beginning of the + * range. This is for the benefit of users which have not yet been + * converted to use multi-index entries. + */ +void xas_create_range(struct xa_state *xas) +{ + unsigned long index = xas->xa_index; + unsigned char shift = xas->xa_shift; + unsigned char sibs = xas->xa_sibs; + + xas->xa_index |= ((sibs + 1) << shift) - 1; + if (xas_is_node(xas) && xas->xa_node->shift == xas->xa_shift) + xas->xa_offset |= sibs; + xas->xa_shift = 0; + xas->xa_sibs = 0; + + for (;;) { + xas_create(xas); + if (xas_error(xas)) + goto restore; + if (xas->xa_index <= (index | XA_CHUNK_MASK)) + goto success; + xas->xa_index -= XA_CHUNK_SIZE; + + for (;;) { + struct xa_node *node = xas->xa_node; + xas->xa_node = xa_parent_locked(xas->xa, node); + xas->xa_offset = node->offset - 1; + if (node->offset != 0) + break; + } + } + +restore: + xas->xa_shift = shift; + xas->xa_sibs = sibs; + xas->xa_index = index; + return; +success: + xas->xa_index = index; + if (xas->xa_node) + xas_set_offset(xas); +} +EXPORT_SYMBOL_GPL(xas_create_range); + static void update_node(struct xa_state *xas, struct xa_node *node, int count, int values) { -- cgit