mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-05 13:16:39 +07:00
590b5b7d86
The kzalloc_node() function has a 2-factor argument form, kcalloc_node(). This patch replaces cases of: kzalloc_node(a * b, gfp, node) with: kcalloc_node(a * b, gfp, node) as well as handling cases of: kzalloc_node(a * b * c, gfp, node) with: kzalloc_node(array3_size(a, b, c), gfp, node) as it's slightly less ugly than: kcalloc_node(array_size(a, b), c, gfp, node) This does, however, attempt to ignore constant size factors like: kzalloc_node(4 * 1024, gfp, node) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kzalloc_node( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kzalloc_node( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kzalloc_node( - sizeof(u8) * (COUNT) + COUNT , ...) | kzalloc_node( - sizeof(__u8) * (COUNT) + COUNT , ...) | kzalloc_node( - sizeof(char) * (COUNT) + COUNT , ...) | kzalloc_node( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kzalloc_node( - sizeof(u8) * COUNT + COUNT , ...) | kzalloc_node( - sizeof(__u8) * COUNT + COUNT , ...) | kzalloc_node( - sizeof(char) * COUNT + COUNT , ...) | kzalloc_node( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kzalloc_node + kcalloc_node ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kzalloc_node + kcalloc_node ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kzalloc_node( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc_node( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc_node( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc_node( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc_node( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc_node( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc_node( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc_node( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kzalloc_node( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc_node( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc_node( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc_node( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc_node( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kzalloc_node( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kzalloc_node( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kzalloc_node(C1 * C2 * C3, ...) | kzalloc_node( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kzalloc_node( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kzalloc_node( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kzalloc_node( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kzalloc_node(sizeof(THING) * C2, ...) | kzalloc_node(sizeof(TYPE) * C2, ...) | kzalloc_node(C1 * C2 * C3, ...) | kzalloc_node(C1 * C2, ...) | - kzalloc_node + kcalloc_node ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kzalloc_node + kcalloc_node ( - (E1) * E2 + E1, E2 , ...) | - kzalloc_node + kcalloc_node ( - (E1) * (E2) + E1, E2 , ...) | - kzalloc_node + kcalloc_node ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
582 lines
14 KiB
C
582 lines
14 KiB
C
/*
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* Copyright (C) 2016 Facebook
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* Copyright (C) 2013-2014 Jens Axboe
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public
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* License v2 as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <https://www.gnu.org/licenses/>.
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*/
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#include <linux/sched.h>
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#include <linux/random.h>
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#include <linux/sbitmap.h>
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#include <linux/seq_file.h>
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int sbitmap_init_node(struct sbitmap *sb, unsigned int depth, int shift,
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gfp_t flags, int node)
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{
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unsigned int bits_per_word;
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unsigned int i;
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if (shift < 0) {
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shift = ilog2(BITS_PER_LONG);
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/*
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* If the bitmap is small, shrink the number of bits per word so
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* we spread over a few cachelines, at least. If less than 4
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* bits, just forget about it, it's not going to work optimally
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* anyway.
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*/
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if (depth >= 4) {
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while ((4U << shift) > depth)
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shift--;
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}
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}
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bits_per_word = 1U << shift;
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if (bits_per_word > BITS_PER_LONG)
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return -EINVAL;
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sb->shift = shift;
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sb->depth = depth;
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sb->map_nr = DIV_ROUND_UP(sb->depth, bits_per_word);
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if (depth == 0) {
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sb->map = NULL;
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return 0;
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}
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sb->map = kcalloc_node(sb->map_nr, sizeof(*sb->map), flags, node);
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if (!sb->map)
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return -ENOMEM;
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for (i = 0; i < sb->map_nr; i++) {
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sb->map[i].depth = min(depth, bits_per_word);
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depth -= sb->map[i].depth;
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}
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return 0;
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}
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EXPORT_SYMBOL_GPL(sbitmap_init_node);
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void sbitmap_resize(struct sbitmap *sb, unsigned int depth)
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{
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unsigned int bits_per_word = 1U << sb->shift;
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unsigned int i;
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sb->depth = depth;
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sb->map_nr = DIV_ROUND_UP(sb->depth, bits_per_word);
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for (i = 0; i < sb->map_nr; i++) {
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sb->map[i].depth = min(depth, bits_per_word);
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depth -= sb->map[i].depth;
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}
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}
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EXPORT_SYMBOL_GPL(sbitmap_resize);
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static int __sbitmap_get_word(unsigned long *word, unsigned long depth,
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unsigned int hint, bool wrap)
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{
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unsigned int orig_hint = hint;
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int nr;
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while (1) {
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nr = find_next_zero_bit(word, depth, hint);
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if (unlikely(nr >= depth)) {
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/*
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* We started with an offset, and we didn't reset the
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* offset to 0 in a failure case, so start from 0 to
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* exhaust the map.
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*/
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if (orig_hint && hint && wrap) {
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hint = orig_hint = 0;
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continue;
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}
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return -1;
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}
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if (!test_and_set_bit_lock(nr, word))
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break;
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hint = nr + 1;
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if (hint >= depth - 1)
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hint = 0;
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}
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return nr;
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}
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int sbitmap_get(struct sbitmap *sb, unsigned int alloc_hint, bool round_robin)
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{
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unsigned int i, index;
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int nr = -1;
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index = SB_NR_TO_INDEX(sb, alloc_hint);
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for (i = 0; i < sb->map_nr; i++) {
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nr = __sbitmap_get_word(&sb->map[index].word,
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sb->map[index].depth,
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SB_NR_TO_BIT(sb, alloc_hint),
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!round_robin);
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if (nr != -1) {
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nr += index << sb->shift;
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break;
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}
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/* Jump to next index. */
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index++;
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alloc_hint = index << sb->shift;
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if (index >= sb->map_nr) {
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index = 0;
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alloc_hint = 0;
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}
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}
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return nr;
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}
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EXPORT_SYMBOL_GPL(sbitmap_get);
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int sbitmap_get_shallow(struct sbitmap *sb, unsigned int alloc_hint,
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unsigned long shallow_depth)
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{
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unsigned int i, index;
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int nr = -1;
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index = SB_NR_TO_INDEX(sb, alloc_hint);
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for (i = 0; i < sb->map_nr; i++) {
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nr = __sbitmap_get_word(&sb->map[index].word,
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min(sb->map[index].depth, shallow_depth),
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SB_NR_TO_BIT(sb, alloc_hint), true);
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if (nr != -1) {
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nr += index << sb->shift;
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break;
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}
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/* Jump to next index. */
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index++;
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alloc_hint = index << sb->shift;
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if (index >= sb->map_nr) {
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index = 0;
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alloc_hint = 0;
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}
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}
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return nr;
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}
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EXPORT_SYMBOL_GPL(sbitmap_get_shallow);
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bool sbitmap_any_bit_set(const struct sbitmap *sb)
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{
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unsigned int i;
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for (i = 0; i < sb->map_nr; i++) {
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if (sb->map[i].word)
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return true;
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}
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return false;
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}
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EXPORT_SYMBOL_GPL(sbitmap_any_bit_set);
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bool sbitmap_any_bit_clear(const struct sbitmap *sb)
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{
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unsigned int i;
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for (i = 0; i < sb->map_nr; i++) {
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const struct sbitmap_word *word = &sb->map[i];
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unsigned long ret;
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ret = find_first_zero_bit(&word->word, word->depth);
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if (ret < word->depth)
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return true;
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}
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return false;
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}
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EXPORT_SYMBOL_GPL(sbitmap_any_bit_clear);
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unsigned int sbitmap_weight(const struct sbitmap *sb)
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{
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unsigned int i, weight = 0;
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for (i = 0; i < sb->map_nr; i++) {
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const struct sbitmap_word *word = &sb->map[i];
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weight += bitmap_weight(&word->word, word->depth);
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}
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return weight;
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}
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EXPORT_SYMBOL_GPL(sbitmap_weight);
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void sbitmap_show(struct sbitmap *sb, struct seq_file *m)
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{
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seq_printf(m, "depth=%u\n", sb->depth);
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seq_printf(m, "busy=%u\n", sbitmap_weight(sb));
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seq_printf(m, "bits_per_word=%u\n", 1U << sb->shift);
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seq_printf(m, "map_nr=%u\n", sb->map_nr);
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}
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EXPORT_SYMBOL_GPL(sbitmap_show);
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static inline void emit_byte(struct seq_file *m, unsigned int offset, u8 byte)
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{
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if ((offset & 0xf) == 0) {
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if (offset != 0)
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seq_putc(m, '\n');
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seq_printf(m, "%08x:", offset);
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}
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if ((offset & 0x1) == 0)
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seq_putc(m, ' ');
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seq_printf(m, "%02x", byte);
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}
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void sbitmap_bitmap_show(struct sbitmap *sb, struct seq_file *m)
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{
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u8 byte = 0;
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unsigned int byte_bits = 0;
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unsigned int offset = 0;
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int i;
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for (i = 0; i < sb->map_nr; i++) {
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unsigned long word = READ_ONCE(sb->map[i].word);
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unsigned int word_bits = READ_ONCE(sb->map[i].depth);
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while (word_bits > 0) {
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unsigned int bits = min(8 - byte_bits, word_bits);
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byte |= (word & (BIT(bits) - 1)) << byte_bits;
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byte_bits += bits;
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if (byte_bits == 8) {
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emit_byte(m, offset, byte);
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byte = 0;
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byte_bits = 0;
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offset++;
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}
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word >>= bits;
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word_bits -= bits;
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}
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}
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if (byte_bits) {
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emit_byte(m, offset, byte);
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offset++;
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}
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if (offset)
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seq_putc(m, '\n');
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}
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EXPORT_SYMBOL_GPL(sbitmap_bitmap_show);
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static unsigned int sbq_calc_wake_batch(struct sbitmap_queue *sbq,
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unsigned int depth)
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{
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unsigned int wake_batch;
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unsigned int shallow_depth;
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/*
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* For each batch, we wake up one queue. We need to make sure that our
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* batch size is small enough that the full depth of the bitmap,
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* potentially limited by a shallow depth, is enough to wake up all of
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* the queues.
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*
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* Each full word of the bitmap has bits_per_word bits, and there might
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* be a partial word. There are depth / bits_per_word full words and
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* depth % bits_per_word bits left over. In bitwise arithmetic:
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*
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* bits_per_word = 1 << shift
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* depth / bits_per_word = depth >> shift
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* depth % bits_per_word = depth & ((1 << shift) - 1)
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*
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* Each word can be limited to sbq->min_shallow_depth bits.
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*/
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shallow_depth = min(1U << sbq->sb.shift, sbq->min_shallow_depth);
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depth = ((depth >> sbq->sb.shift) * shallow_depth +
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min(depth & ((1U << sbq->sb.shift) - 1), shallow_depth));
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wake_batch = clamp_t(unsigned int, depth / SBQ_WAIT_QUEUES, 1,
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SBQ_WAKE_BATCH);
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return wake_batch;
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}
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int sbitmap_queue_init_node(struct sbitmap_queue *sbq, unsigned int depth,
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int shift, bool round_robin, gfp_t flags, int node)
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{
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int ret;
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int i;
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ret = sbitmap_init_node(&sbq->sb, depth, shift, flags, node);
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if (ret)
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return ret;
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sbq->alloc_hint = alloc_percpu_gfp(unsigned int, flags);
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if (!sbq->alloc_hint) {
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sbitmap_free(&sbq->sb);
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return -ENOMEM;
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}
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if (depth && !round_robin) {
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for_each_possible_cpu(i)
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*per_cpu_ptr(sbq->alloc_hint, i) = prandom_u32() % depth;
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}
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sbq->min_shallow_depth = UINT_MAX;
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sbq->wake_batch = sbq_calc_wake_batch(sbq, depth);
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atomic_set(&sbq->wake_index, 0);
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sbq->ws = kzalloc_node(SBQ_WAIT_QUEUES * sizeof(*sbq->ws), flags, node);
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if (!sbq->ws) {
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free_percpu(sbq->alloc_hint);
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sbitmap_free(&sbq->sb);
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return -ENOMEM;
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}
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for (i = 0; i < SBQ_WAIT_QUEUES; i++) {
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init_waitqueue_head(&sbq->ws[i].wait);
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atomic_set(&sbq->ws[i].wait_cnt, sbq->wake_batch);
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}
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sbq->round_robin = round_robin;
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return 0;
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}
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EXPORT_SYMBOL_GPL(sbitmap_queue_init_node);
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static void sbitmap_queue_update_wake_batch(struct sbitmap_queue *sbq,
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unsigned int depth)
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{
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unsigned int wake_batch = sbq_calc_wake_batch(sbq, depth);
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int i;
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if (sbq->wake_batch != wake_batch) {
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WRITE_ONCE(sbq->wake_batch, wake_batch);
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/*
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* Pairs with the memory barrier in sbitmap_queue_wake_up()
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* to ensure that the batch size is updated before the wait
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* counts.
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*/
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smp_mb__before_atomic();
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for (i = 0; i < SBQ_WAIT_QUEUES; i++)
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atomic_set(&sbq->ws[i].wait_cnt, 1);
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}
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}
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void sbitmap_queue_resize(struct sbitmap_queue *sbq, unsigned int depth)
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{
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sbitmap_queue_update_wake_batch(sbq, depth);
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sbitmap_resize(&sbq->sb, depth);
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}
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EXPORT_SYMBOL_GPL(sbitmap_queue_resize);
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int __sbitmap_queue_get(struct sbitmap_queue *sbq)
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{
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unsigned int hint, depth;
|
|
int nr;
|
|
|
|
hint = this_cpu_read(*sbq->alloc_hint);
|
|
depth = READ_ONCE(sbq->sb.depth);
|
|
if (unlikely(hint >= depth)) {
|
|
hint = depth ? prandom_u32() % depth : 0;
|
|
this_cpu_write(*sbq->alloc_hint, hint);
|
|
}
|
|
nr = sbitmap_get(&sbq->sb, hint, sbq->round_robin);
|
|
|
|
if (nr == -1) {
|
|
/* If the map is full, a hint won't do us much good. */
|
|
this_cpu_write(*sbq->alloc_hint, 0);
|
|
} else if (nr == hint || unlikely(sbq->round_robin)) {
|
|
/* Only update the hint if we used it. */
|
|
hint = nr + 1;
|
|
if (hint >= depth - 1)
|
|
hint = 0;
|
|
this_cpu_write(*sbq->alloc_hint, hint);
|
|
}
|
|
|
|
return nr;
|
|
}
|
|
EXPORT_SYMBOL_GPL(__sbitmap_queue_get);
|
|
|
|
int __sbitmap_queue_get_shallow(struct sbitmap_queue *sbq,
|
|
unsigned int shallow_depth)
|
|
{
|
|
unsigned int hint, depth;
|
|
int nr;
|
|
|
|
WARN_ON_ONCE(shallow_depth < sbq->min_shallow_depth);
|
|
|
|
hint = this_cpu_read(*sbq->alloc_hint);
|
|
depth = READ_ONCE(sbq->sb.depth);
|
|
if (unlikely(hint >= depth)) {
|
|
hint = depth ? prandom_u32() % depth : 0;
|
|
this_cpu_write(*sbq->alloc_hint, hint);
|
|
}
|
|
nr = sbitmap_get_shallow(&sbq->sb, hint, shallow_depth);
|
|
|
|
if (nr == -1) {
|
|
/* If the map is full, a hint won't do us much good. */
|
|
this_cpu_write(*sbq->alloc_hint, 0);
|
|
} else if (nr == hint || unlikely(sbq->round_robin)) {
|
|
/* Only update the hint if we used it. */
|
|
hint = nr + 1;
|
|
if (hint >= depth - 1)
|
|
hint = 0;
|
|
this_cpu_write(*sbq->alloc_hint, hint);
|
|
}
|
|
|
|
return nr;
|
|
}
|
|
EXPORT_SYMBOL_GPL(__sbitmap_queue_get_shallow);
|
|
|
|
void sbitmap_queue_min_shallow_depth(struct sbitmap_queue *sbq,
|
|
unsigned int min_shallow_depth)
|
|
{
|
|
sbq->min_shallow_depth = min_shallow_depth;
|
|
sbitmap_queue_update_wake_batch(sbq, sbq->sb.depth);
|
|
}
|
|
EXPORT_SYMBOL_GPL(sbitmap_queue_min_shallow_depth);
|
|
|
|
static struct sbq_wait_state *sbq_wake_ptr(struct sbitmap_queue *sbq)
|
|
{
|
|
int i, wake_index;
|
|
|
|
wake_index = atomic_read(&sbq->wake_index);
|
|
for (i = 0; i < SBQ_WAIT_QUEUES; i++) {
|
|
struct sbq_wait_state *ws = &sbq->ws[wake_index];
|
|
|
|
if (waitqueue_active(&ws->wait)) {
|
|
int o = atomic_read(&sbq->wake_index);
|
|
|
|
if (wake_index != o)
|
|
atomic_cmpxchg(&sbq->wake_index, o, wake_index);
|
|
return ws;
|
|
}
|
|
|
|
wake_index = sbq_index_inc(wake_index);
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static bool __sbq_wake_up(struct sbitmap_queue *sbq)
|
|
{
|
|
struct sbq_wait_state *ws;
|
|
unsigned int wake_batch;
|
|
int wait_cnt;
|
|
|
|
ws = sbq_wake_ptr(sbq);
|
|
if (!ws)
|
|
return false;
|
|
|
|
wait_cnt = atomic_dec_return(&ws->wait_cnt);
|
|
if (wait_cnt <= 0) {
|
|
int ret;
|
|
|
|
wake_batch = READ_ONCE(sbq->wake_batch);
|
|
|
|
/*
|
|
* Pairs with the memory barrier in sbitmap_queue_resize() to
|
|
* ensure that we see the batch size update before the wait
|
|
* count is reset.
|
|
*/
|
|
smp_mb__before_atomic();
|
|
|
|
/*
|
|
* For concurrent callers of this, the one that failed the
|
|
* atomic_cmpxhcg() race should call this function again
|
|
* to wakeup a new batch on a different 'ws'.
|
|
*/
|
|
ret = atomic_cmpxchg(&ws->wait_cnt, wait_cnt, wake_batch);
|
|
if (ret == wait_cnt) {
|
|
sbq_index_atomic_inc(&sbq->wake_index);
|
|
wake_up_nr(&ws->wait, wake_batch);
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
void sbitmap_queue_wake_up(struct sbitmap_queue *sbq)
|
|
{
|
|
while (__sbq_wake_up(sbq))
|
|
;
|
|
}
|
|
EXPORT_SYMBOL_GPL(sbitmap_queue_wake_up);
|
|
|
|
void sbitmap_queue_clear(struct sbitmap_queue *sbq, unsigned int nr,
|
|
unsigned int cpu)
|
|
{
|
|
sbitmap_clear_bit_unlock(&sbq->sb, nr);
|
|
/*
|
|
* Pairs with the memory barrier in set_current_state() to ensure the
|
|
* proper ordering of clear_bit_unlock()/waitqueue_active() in the waker
|
|
* and test_and_set_bit_lock()/prepare_to_wait()/finish_wait() in the
|
|
* waiter. See the comment on waitqueue_active().
|
|
*/
|
|
smp_mb__after_atomic();
|
|
sbitmap_queue_wake_up(sbq);
|
|
|
|
if (likely(!sbq->round_robin && nr < sbq->sb.depth))
|
|
*per_cpu_ptr(sbq->alloc_hint, cpu) = nr;
|
|
}
|
|
EXPORT_SYMBOL_GPL(sbitmap_queue_clear);
|
|
|
|
void sbitmap_queue_wake_all(struct sbitmap_queue *sbq)
|
|
{
|
|
int i, wake_index;
|
|
|
|
/*
|
|
* Pairs with the memory barrier in set_current_state() like in
|
|
* sbitmap_queue_wake_up().
|
|
*/
|
|
smp_mb();
|
|
wake_index = atomic_read(&sbq->wake_index);
|
|
for (i = 0; i < SBQ_WAIT_QUEUES; i++) {
|
|
struct sbq_wait_state *ws = &sbq->ws[wake_index];
|
|
|
|
if (waitqueue_active(&ws->wait))
|
|
wake_up(&ws->wait);
|
|
|
|
wake_index = sbq_index_inc(wake_index);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(sbitmap_queue_wake_all);
|
|
|
|
void sbitmap_queue_show(struct sbitmap_queue *sbq, struct seq_file *m)
|
|
{
|
|
bool first;
|
|
int i;
|
|
|
|
sbitmap_show(&sbq->sb, m);
|
|
|
|
seq_puts(m, "alloc_hint={");
|
|
first = true;
|
|
for_each_possible_cpu(i) {
|
|
if (!first)
|
|
seq_puts(m, ", ");
|
|
first = false;
|
|
seq_printf(m, "%u", *per_cpu_ptr(sbq->alloc_hint, i));
|
|
}
|
|
seq_puts(m, "}\n");
|
|
|
|
seq_printf(m, "wake_batch=%u\n", sbq->wake_batch);
|
|
seq_printf(m, "wake_index=%d\n", atomic_read(&sbq->wake_index));
|
|
|
|
seq_puts(m, "ws={\n");
|
|
for (i = 0; i < SBQ_WAIT_QUEUES; i++) {
|
|
struct sbq_wait_state *ws = &sbq->ws[i];
|
|
|
|
seq_printf(m, "\t{.wait_cnt=%d, .wait=%s},\n",
|
|
atomic_read(&ws->wait_cnt),
|
|
waitqueue_active(&ws->wait) ? "active" : "inactive");
|
|
}
|
|
seq_puts(m, "}\n");
|
|
|
|
seq_printf(m, "round_robin=%d\n", sbq->round_robin);
|
|
seq_printf(m, "min_shallow_depth=%u\n", sbq->min_shallow_depth);
|
|
}
|
|
EXPORT_SYMBOL_GPL(sbitmap_queue_show);
|