From 24af1ccfe12adddbe17d11801e1689791a4cc282 Mon Sep 17 00:00:00 2001 From: Omar Sandoval Date: Wed, 25 Jan 2017 14:32:13 -0800 Subject: [PATCH] sbitmap: add helpers for dumping to a seq_file This is useful debugging information that will be used in the blk-mq debugfs directory. Reviewed-by: Hannes Reinecke Signed-off-by: Omar Sandoval Changed 'weight' to 'busy'. Signed-off-by: Jens Axboe --- include/linux/sbitmap.h | 30 ++++++++++++++ lib/sbitmap.c | 91 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 121 insertions(+) diff --git a/include/linux/sbitmap.h b/include/linux/sbitmap.h index f017fd6e69c4..d4e0a204c118 100644 --- a/include/linux/sbitmap.h +++ b/include/linux/sbitmap.h @@ -258,6 +258,26 @@ static inline int sbitmap_test_bit(struct sbitmap *sb, unsigned int bitnr) unsigned int sbitmap_weight(const struct sbitmap *sb); +/** + * sbitmap_show() - Dump &struct sbitmap information to a &struct seq_file. + * @sb: Bitmap to show. + * @m: struct seq_file to write to. + * + * This is intended for debugging. The format may change at any time. + */ +void sbitmap_show(struct sbitmap *sb, struct seq_file *m); + +/** + * sbitmap_bitmap_show() - Write a hex dump of a &struct sbitmap to a &struct + * seq_file. + * @sb: Bitmap to show. + * @m: struct seq_file to write to. + * + * This is intended for debugging. The output isn't guaranteed to be internally + * consistent. + */ +void sbitmap_bitmap_show(struct sbitmap *sb, struct seq_file *m); + /** * sbitmap_queue_init_node() - Initialize a &struct sbitmap_queue on a specific * memory node. @@ -370,4 +390,14 @@ static inline struct sbq_wait_state *sbq_wait_ptr(struct sbitmap_queue *sbq, */ void sbitmap_queue_wake_all(struct sbitmap_queue *sbq); +/** + * sbitmap_queue_show() - Dump &struct sbitmap_queue information to a &struct + * seq_file. + * @sbq: Bitmap queue to show. + * @m: struct seq_file to write to. + * + * This is intended for debugging. The format may change at any time. + */ +void sbitmap_queue_show(struct sbitmap_queue *sbq, struct seq_file *m); + #endif /* __LINUX_SCALE_BITMAP_H */ diff --git a/lib/sbitmap.c b/lib/sbitmap.c index 8f5c3b268c77..55e11c4b2f3b 100644 --- a/lib/sbitmap.c +++ b/lib/sbitmap.c @@ -17,6 +17,7 @@ #include #include +#include int sbitmap_init_node(struct sbitmap *sb, unsigned int depth, int shift, gfp_t flags, int node) @@ -180,6 +181,62 @@ unsigned int sbitmap_weight(const struct sbitmap *sb) } EXPORT_SYMBOL_GPL(sbitmap_weight); +void sbitmap_show(struct sbitmap *sb, struct seq_file *m) +{ + seq_printf(m, "depth=%u\n", sb->depth); + seq_printf(m, "busy=%u\n", sbitmap_weight(sb)); + seq_printf(m, "bits_per_word=%u\n", 1U << sb->shift); + seq_printf(m, "map_nr=%u\n", sb->map_nr); +} +EXPORT_SYMBOL_GPL(sbitmap_show); + +static inline void emit_byte(struct seq_file *m, unsigned int offset, u8 byte) +{ + if ((offset & 0xf) == 0) { + if (offset != 0) + seq_putc(m, '\n'); + seq_printf(m, "%08x:", offset); + } + if ((offset & 0x1) == 0) + seq_putc(m, ' '); + seq_printf(m, "%02x", byte); +} + +void sbitmap_bitmap_show(struct sbitmap *sb, struct seq_file *m) +{ + u8 byte = 0; + unsigned int byte_bits = 0; + unsigned int offset = 0; + int i; + + for (i = 0; i < sb->map_nr; i++) { + unsigned long word = READ_ONCE(sb->map[i].word); + unsigned int word_bits = READ_ONCE(sb->map[i].depth); + + while (word_bits > 0) { + unsigned int bits = min(8 - byte_bits, word_bits); + + byte |= (word & (BIT(bits) - 1)) << byte_bits; + byte_bits += bits; + if (byte_bits == 8) { + emit_byte(m, offset, byte); + byte = 0; + byte_bits = 0; + offset++; + } + word >>= bits; + word_bits -= bits; + } + } + if (byte_bits) { + emit_byte(m, offset, byte); + offset++; + } + if (offset) + seq_putc(m, '\n'); +} +EXPORT_SYMBOL_GPL(sbitmap_bitmap_show); + static unsigned int sbq_calc_wake_batch(unsigned int depth) { unsigned int wake_batch; @@ -377,3 +434,37 @@ void sbitmap_queue_wake_all(struct sbitmap_queue *sbq) } } 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); +} +EXPORT_SYMBOL_GPL(sbitmap_queue_show); -- 2.30.2