diff options
Diffstat (limited to 'drivers/block')
-rw-r--r-- | drivers/block/loop.c | 3 | ||||
-rw-r--r-- | drivers/block/zram/Kconfig | 14 | ||||
-rw-r--r-- | drivers/block/zram/zram_drv.c | 165 | ||||
-rw-r--r-- | drivers/block/zram/zram_drv.h | 14 |
4 files changed, 177 insertions, 19 deletions
diff --git a/drivers/block/loop.c b/drivers/block/loop.c index f8f3ca6e77fd..21e6d1b3b393 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -76,6 +76,8 @@ #include <linux/miscdevice.h> #include <linux/falloc.h> #include <linux/uio.h> +#include <linux/ioprio.h> + #include "loop.h" #include <linux/uaccess.h> @@ -559,6 +561,7 @@ static int lo_rw_aio(struct loop_device *lo, struct loop_cmd *cmd, cmd->iocb.ki_filp = file; cmd->iocb.ki_complete = lo_rw_aio_complete; cmd->iocb.ki_flags = IOCB_DIRECT; + cmd->iocb.ki_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_NONE, 0); if (cmd->css) kthread_associate_blkcg(cmd->css); diff --git a/drivers/block/zram/Kconfig b/drivers/block/zram/Kconfig index ac3a31d433b2..635235759a0a 100644 --- a/drivers/block/zram/Kconfig +++ b/drivers/block/zram/Kconfig @@ -13,7 +13,7 @@ config ZRAM It has several use cases, for example: /tmp storage, use as swap disks and maybe many more. - See zram.txt for more information. + See Documentation/blockdev/zram.txt for more information. config ZRAM_WRITEBACK bool "Write back incompressible page to backing device" @@ -25,4 +25,14 @@ config ZRAM_WRITEBACK For this feature, admin should set up backing device via /sys/block/zramX/backing_dev. - See zram.txt for more infomration. + See Documentation/blockdev/zram.txt for more information. + +config ZRAM_MEMORY_TRACKING + bool "Track zRam block status" + depends on ZRAM && DEBUG_FS + help + With this feature, admin can track the state of allocated blocks + of zRAM. Admin could see the information via + /sys/kernel/debug/zram/zramX/block_state. + + See Documentation/blockdev/zram.txt for more information. diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index 0f3fadd71230..da51293e7c03 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -31,6 +31,7 @@ #include <linux/err.h> #include <linux/idr.h> #include <linux/sysfs.h> +#include <linux/debugfs.h> #include <linux/cpuhotplug.h> #include "zram_drv.h" @@ -52,11 +53,28 @@ static size_t huge_class_size; static void zram_free_page(struct zram *zram, size_t index); +static void zram_slot_lock(struct zram *zram, u32 index) +{ + bit_spin_lock(ZRAM_LOCK, &zram->table[index].value); +} + +static void zram_slot_unlock(struct zram *zram, u32 index) +{ + bit_spin_unlock(ZRAM_LOCK, &zram->table[index].value); +} + static inline bool init_done(struct zram *zram) { return zram->disksize; } +static inline bool zram_allocated(struct zram *zram, u32 index) +{ + + return (zram->table[index].value >> (ZRAM_FLAG_SHIFT + 1)) || + zram->table[index].handle; +} + static inline struct zram *dev_to_zram(struct device *dev) { return (struct zram *)dev_to_disk(dev)->private_data; @@ -73,7 +91,7 @@ static void zram_set_handle(struct zram *zram, u32 index, unsigned long handle) } /* flag operations require table entry bit_spin_lock() being held */ -static int zram_test_flag(struct zram *zram, u32 index, +static bool zram_test_flag(struct zram *zram, u32 index, enum zram_pageflags flag) { return zram->table[index].value & BIT(flag); @@ -600,6 +618,114 @@ static int read_from_bdev(struct zram *zram, struct bio_vec *bvec, static void zram_wb_clear(struct zram *zram, u32 index) {} #endif +#ifdef CONFIG_ZRAM_MEMORY_TRACKING + +static struct dentry *zram_debugfs_root; + +static void zram_debugfs_create(void) +{ + zram_debugfs_root = debugfs_create_dir("zram", NULL); +} + +static void zram_debugfs_destroy(void) +{ + debugfs_remove_recursive(zram_debugfs_root); +} + +static void zram_accessed(struct zram *zram, u32 index) +{ + zram->table[index].ac_time = ktime_get_boottime(); +} + +static void zram_reset_access(struct zram *zram, u32 index) +{ + zram->table[index].ac_time = 0; +} + +static ssize_t read_block_state(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + char *kbuf; + ssize_t index, written = 0; + struct zram *zram = file->private_data; + unsigned long nr_pages = zram->disksize >> PAGE_SHIFT; + struct timespec64 ts; + + kbuf = kvmalloc(count, GFP_KERNEL); + if (!kbuf) + return -ENOMEM; + + down_read(&zram->init_lock); + if (!init_done(zram)) { + up_read(&zram->init_lock); + kvfree(kbuf); + return -EINVAL; + } + + for (index = *ppos; index < nr_pages; index++) { + int copied; + + zram_slot_lock(zram, index); + if (!zram_allocated(zram, index)) + goto next; + + ts = ktime_to_timespec64(zram->table[index].ac_time); + copied = snprintf(kbuf + written, count, + "%12zd %12lld.%06lu %c%c%c\n", + index, (s64)ts.tv_sec, + ts.tv_nsec / NSEC_PER_USEC, + zram_test_flag(zram, index, ZRAM_SAME) ? 's' : '.', + zram_test_flag(zram, index, ZRAM_WB) ? 'w' : '.', + zram_test_flag(zram, index, ZRAM_HUGE) ? 'h' : '.'); + + if (count < copied) { + zram_slot_unlock(zram, index); + break; + } + written += copied; + count -= copied; +next: + zram_slot_unlock(zram, index); + *ppos += 1; + } + + up_read(&zram->init_lock); + if (copy_to_user(buf, kbuf, written)) + written = -EFAULT; + kvfree(kbuf); + + return written; +} + +static const struct file_operations proc_zram_block_state_op = { + .open = simple_open, + .read = read_block_state, + .llseek = default_llseek, +}; + +static void zram_debugfs_register(struct zram *zram) +{ + if (!zram_debugfs_root) + return; + + zram->debugfs_dir = debugfs_create_dir(zram->disk->disk_name, + zram_debugfs_root); + debugfs_create_file("block_state", 0400, zram->debugfs_dir, + zram, &proc_zram_block_state_op); +} + +static void zram_debugfs_unregister(struct zram *zram) +{ + debugfs_remove_recursive(zram->debugfs_dir); +} +#else +static void zram_debugfs_create(void) {}; +static void zram_debugfs_destroy(void) {}; +static void zram_accessed(struct zram *zram, u32 index) {}; +static void zram_reset_access(struct zram *zram, u32 index) {}; +static void zram_debugfs_register(struct zram *zram) {}; +static void zram_debugfs_unregister(struct zram *zram) {}; +#endif /* * We switched to per-cpu streams and this attr is not needed anymore. @@ -719,14 +845,15 @@ static ssize_t mm_stat_show(struct device *dev, max_used = atomic_long_read(&zram->stats.max_used_pages); ret = scnprintf(buf, PAGE_SIZE, - "%8llu %8llu %8llu %8lu %8ld %8llu %8lu\n", + "%8llu %8llu %8llu %8lu %8ld %8llu %8lu %8llu\n", orig_size << PAGE_SHIFT, (u64)atomic64_read(&zram->stats.compr_data_size), mem_used << PAGE_SHIFT, zram->limit_pages << PAGE_SHIFT, max_used << PAGE_SHIFT, (u64)atomic64_read(&zram->stats.same_pages), - pool_stats.pages_compacted); + pool_stats.pages_compacted, + (u64)atomic64_read(&zram->stats.huge_pages)); up_read(&zram->init_lock); return ret; @@ -753,16 +880,6 @@ static DEVICE_ATTR_RO(io_stat); static DEVICE_ATTR_RO(mm_stat); static DEVICE_ATTR_RO(debug_stat); -static void zram_slot_lock(struct zram *zram, u32 index) -{ - bit_spin_lock(ZRAM_ACCESS, &zram->table[index].value); -} - -static void zram_slot_unlock(struct zram *zram, u32 index) -{ - bit_spin_unlock(ZRAM_ACCESS, &zram->table[index].value); -} - static void zram_meta_free(struct zram *zram, u64 disksize) { size_t num_pages = disksize >> PAGE_SHIFT; @@ -805,6 +922,13 @@ static void zram_free_page(struct zram *zram, size_t index) { unsigned long handle; + zram_reset_access(zram, index); + + if (zram_test_flag(zram, index, ZRAM_HUGE)) { + zram_clear_flag(zram, index, ZRAM_HUGE); + atomic64_dec(&zram->stats.huge_pages); + } + if (zram_wb_enabled(zram) && zram_test_flag(zram, index, ZRAM_WB)) { zram_wb_clear(zram, index); atomic64_dec(&zram->stats.pages_stored); @@ -973,6 +1097,7 @@ compress_again: } if (unlikely(comp_len >= huge_class_size)) { + comp_len = PAGE_SIZE; if (zram_wb_enabled(zram) && allow_wb) { zcomp_stream_put(zram->comp); ret = write_to_bdev(zram, bvec, index, bio, &element); @@ -984,7 +1109,6 @@ compress_again: allow_wb = false; goto compress_again; } - comp_len = PAGE_SIZE; } /* @@ -1046,6 +1170,11 @@ out: zram_slot_lock(zram, index); zram_free_page(zram, index); + if (comp_len == PAGE_SIZE) { + zram_set_flag(zram, index, ZRAM_HUGE); + atomic64_inc(&zram->stats.huge_pages); + } + if (flags) { zram_set_flag(zram, index, flags); zram_set_element(zram, index, element); @@ -1166,6 +1295,10 @@ static int zram_bvec_rw(struct zram *zram, struct bio_vec *bvec, u32 index, generic_end_io_acct(q, rw_acct, &zram->disk->part0, start_time); + zram_slot_lock(zram, index); + zram_accessed(zram, index); + zram_slot_unlock(zram, index); + if (unlikely(ret < 0)) { if (!is_write) atomic64_inc(&zram->stats.failed_reads); @@ -1577,6 +1710,7 @@ static int zram_add(void) } strlcpy(zram->compressor, default_compressor, sizeof(zram->compressor)); + zram_debugfs_register(zram); pr_info("Added device: %s\n", zram->disk->disk_name); return device_id; @@ -1610,6 +1744,7 @@ static int zram_remove(struct zram *zram) zram->claim = true; mutex_unlock(&bdev->bd_mutex); + zram_debugfs_unregister(zram); /* * Remove sysfs first, so no one will perform a disksize * store while we destroy the devices. This also helps during @@ -1712,6 +1847,7 @@ static void destroy_devices(void) { class_unregister(&zram_control_class); idr_for_each(&zram_index_idr, &zram_remove_cb, NULL); + zram_debugfs_destroy(); idr_destroy(&zram_index_idr); unregister_blkdev(zram_major, "zram"); cpuhp_remove_multi_state(CPUHP_ZCOMP_PREPARE); @@ -1733,6 +1869,7 @@ static int __init zram_init(void) return ret; } + zram_debugfs_create(); zram_major = register_blkdev(0, "zram"); if (zram_major <= 0) { pr_err("Unable to get major number\n"); diff --git a/drivers/block/zram/zram_drv.h b/drivers/block/zram/zram_drv.h index 008861220723..72c8584b6dff 100644 --- a/drivers/block/zram/zram_drv.h +++ b/drivers/block/zram/zram_drv.h @@ -43,10 +43,11 @@ /* Flags for zram pages (table[page_no].value) */ enum zram_pageflags { - /* Page consists the same element */ - ZRAM_SAME = ZRAM_FLAG_SHIFT, - ZRAM_ACCESS, /* page is now accessed */ + /* zram slot is locked */ + ZRAM_LOCK = ZRAM_FLAG_SHIFT, + ZRAM_SAME, /* Page consists the same element */ ZRAM_WB, /* page is stored on backing_device */ + ZRAM_HUGE, /* Incompressible page */ __NR_ZRAM_PAGEFLAGS, }; @@ -60,6 +61,9 @@ struct zram_table_entry { unsigned long element; }; unsigned long value; +#ifdef CONFIG_ZRAM_MEMORY_TRACKING + ktime_t ac_time; +#endif }; struct zram_stats { @@ -71,6 +75,7 @@ struct zram_stats { atomic64_t invalid_io; /* non-page-aligned I/O requests */ atomic64_t notify_free; /* no. of swap slot free notifications */ atomic64_t same_pages; /* no. of same element filled pages */ + atomic64_t huge_pages; /* no. of huge pages */ atomic64_t pages_stored; /* no. of pages currently stored */ atomic_long_t max_used_pages; /* no. of maximum pages stored */ atomic64_t writestall; /* no. of write slow paths */ @@ -107,5 +112,8 @@ struct zram { unsigned long nr_pages; spinlock_t bitmap_lock; #endif +#ifdef CONFIG_ZRAM_MEMORY_TRACKING + struct dentry *debugfs_dir; +#endif }; #endif |