From 5346c27c5fed6b30aff35e1fcb595625097e646c Mon Sep 17 00:00:00 2001 From: Ezequiel Garcia Date: Mon, 3 Dec 2012 10:31:40 -0300 Subject: [PATCH] mtd: nandsim: Introduce debugfs infrastructure It's more user friendly to report debug information and statistics through debugfs, than to use printing facilites. This patch introduces a very minimal debugfs infrastructure and moves eraseblock wear report to an entry located at: /sys/kernel/debug/nandsim/wear_report This means we can remove rptwear option and just let the user get the wear report when we needs to. Signed-off-by: Ezequiel Garcia Signed-off-by: Artem Bityutskiy --- drivers/mtd/nand/nandsim.c | 186 ++++++++++++++++++++++++++----------- 1 file changed, 130 insertions(+), 56 deletions(-) diff --git a/drivers/mtd/nand/nandsim.c b/drivers/mtd/nand/nandsim.c index a932c485eb04..2ab827428f18 100644 --- a/drivers/mtd/nand/nandsim.c +++ b/drivers/mtd/nand/nandsim.c @@ -42,6 +42,8 @@ #include #include #include +#include +#include /* Default simulator parameters values */ #if !defined(CONFIG_NANDSIM_FIRST_ID_BYTE) || \ @@ -105,7 +107,6 @@ static char *weakblocks = NULL; static char *weakpages = NULL; static unsigned int bitflips = 0; static char *gravepages = NULL; -static unsigned int rptwear = 0; static unsigned int overridesize = 0; static char *cache_file = NULL; static unsigned int bbt; @@ -130,7 +131,6 @@ module_param(weakblocks, charp, 0400); module_param(weakpages, charp, 0400); module_param(bitflips, uint, 0400); module_param(gravepages, charp, 0400); -module_param(rptwear, uint, 0400); module_param(overridesize, uint, 0400); module_param(cache_file, charp, 0400); module_param(bbt, uint, 0400); @@ -162,7 +162,6 @@ MODULE_PARM_DESC(bitflips, "Maximum number of random bit flips per page (z MODULE_PARM_DESC(gravepages, "Pages that lose data [: maximum reads (defaults to 3)]" " separated by commas e.g. 1401:2 means page 1401" " can be read only twice before failing"); -MODULE_PARM_DESC(rptwear, "Number of erases between reporting wear, if not zero"); MODULE_PARM_DESC(overridesize, "Specifies the NAND Flash size overriding the ID bytes. " "The size is specified in erase blocks and as the exponent of a power of two" " e.g. 5 means a size of 32 erase blocks"); @@ -286,6 +285,11 @@ MODULE_PARM_DESC(bch, "Enable BCH ecc and set how many bits should " /* Maximum page cache pages needed to read or write a NAND page to the cache_file */ #define NS_MAX_HELD_PAGES 16 +struct nandsim_debug_info { + struct dentry *dfs_root; + struct dentry *dfs_wear_report; +}; + /* * A union to represent flash memory contents and flash buffer. */ @@ -365,6 +369,8 @@ struct nandsim { void *file_buf; struct page *held_pages[NS_MAX_HELD_PAGES]; int held_cnt; + + struct nandsim_debug_info dbg; }; /* @@ -442,11 +448,123 @@ static LIST_HEAD(grave_pages); static unsigned long *erase_block_wear = NULL; static unsigned int wear_eb_count = 0; static unsigned long total_wear = 0; -static unsigned int rptwear_cnt = 0; /* MTD structure for NAND controller */ static struct mtd_info *nsmtd; +static int nandsim_debugfs_show(struct seq_file *m, void *private) +{ + unsigned long wmin = -1, wmax = 0, avg; + unsigned long deciles[10], decile_max[10], tot = 0; + unsigned int i; + + /* Calc wear stats */ + for (i = 0; i < wear_eb_count; ++i) { + unsigned long wear = erase_block_wear[i]; + if (wear < wmin) + wmin = wear; + if (wear > wmax) + wmax = wear; + tot += wear; + } + + for (i = 0; i < 9; ++i) { + deciles[i] = 0; + decile_max[i] = (wmax * (i + 1) + 5) / 10; + } + deciles[9] = 0; + decile_max[9] = wmax; + for (i = 0; i < wear_eb_count; ++i) { + int d; + unsigned long wear = erase_block_wear[i]; + for (d = 0; d < 10; ++d) + if (wear <= decile_max[d]) { + deciles[d] += 1; + break; + } + } + avg = tot / wear_eb_count; + + /* Output wear report */ + seq_printf(m, "Total numbers of erases: %lu\n", tot); + seq_printf(m, "Number of erase blocks: %u\n", wear_eb_count); + seq_printf(m, "Average number of erases: %lu\n", avg); + seq_printf(m, "Maximum number of erases: %lu\n", wmax); + seq_printf(m, "Minimum number of erases: %lu\n", wmin); + for (i = 0; i < 10; ++i) { + unsigned long from = (i ? decile_max[i - 1] + 1 : 0); + if (from > decile_max[i]) + continue; + seq_printf(m, "Number of ebs with erase counts from %lu to %lu : %lu\n", + from, + decile_max[i], + deciles[i]); + } + + return 0; +} + +static int nandsim_debugfs_open(struct inode *inode, struct file *file) +{ + return single_open(file, nandsim_debugfs_show, inode->i_private); +} + +static const struct file_operations dfs_fops = { + .open = nandsim_debugfs_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +/** + * nandsim_debugfs_create - initialize debugfs + * @dev: nandsim device description object + * + * This function creates all debugfs files for UBI device @ubi. Returns zero in + * case of success and a negative error code in case of failure. + */ +static int nandsim_debugfs_create(struct nandsim *dev) +{ + struct nandsim_debug_info *dbg = &dev->dbg; + struct dentry *dent; + int err; + + if (!IS_ENABLED(CONFIG_DEBUG_FS)) + return 0; + + dent = debugfs_create_dir("nandsim", NULL); + if (IS_ERR_OR_NULL(dent)) { + int err = dent ? -ENODEV : PTR_ERR(dent); + + NS_ERR("cannot create \"nandsim\" debugfs directory, err %d\n", + err); + return err; + } + dbg->dfs_root = dent; + + dent = debugfs_create_file("wear_report", S_IRUSR, + dbg->dfs_root, dev, &dfs_fops); + if (IS_ERR_OR_NULL(dent)) + goto out_remove; + dbg->dfs_wear_report = dent; + + return 0; + +out_remove: + debugfs_remove_recursive(dbg->dfs_root); + err = dent ? PTR_ERR(dent) : -ENODEV; + return err; +} + +/** + * nandsim_debugfs_remove - destroy all debugfs files + */ +static void nandsim_debugfs_remove(struct nandsim *ns) +{ + if (IS_ENABLED(CONFIG_DEBUG_FS)) + debugfs_remove_recursive(ns->dbg.dfs_root); +} + /* * Allocate array of page pointers, create slab allocation for an array * and initialize the array by NULL pointers. @@ -911,8 +1029,6 @@ static int setup_wear_reporting(struct mtd_info *mtd) { size_t mem; - if (!rptwear) - return 0; wear_eb_count = div_u64(mtd->size, mtd->erasesize); mem = wear_eb_count * sizeof(unsigned long); if (mem / sizeof(unsigned long) != wear_eb_count) { @@ -929,64 +1045,18 @@ static int setup_wear_reporting(struct mtd_info *mtd) static void update_wear(unsigned int erase_block_no) { - unsigned long wmin = -1, wmax = 0, avg; - unsigned long deciles[10], decile_max[10], tot = 0; - unsigned int i; - if (!erase_block_wear) return; total_wear += 1; + /* + * TODO: Notify this through a debugfs entry, + * instead of showing an error message. + */ if (total_wear == 0) NS_ERR("Erase counter total overflow\n"); erase_block_wear[erase_block_no] += 1; if (erase_block_wear[erase_block_no] == 0) NS_ERR("Erase counter overflow for erase block %u\n", erase_block_no); - rptwear_cnt += 1; - if (rptwear_cnt < rptwear) - return; - rptwear_cnt = 0; - /* Calc wear stats */ - for (i = 0; i < wear_eb_count; ++i) { - unsigned long wear = erase_block_wear[i]; - if (wear < wmin) - wmin = wear; - if (wear > wmax) - wmax = wear; - tot += wear; - } - for (i = 0; i < 9; ++i) { - deciles[i] = 0; - decile_max[i] = (wmax * (i + 1) + 5) / 10; - } - deciles[9] = 0; - decile_max[9] = wmax; - for (i = 0; i < wear_eb_count; ++i) { - int d; - unsigned long wear = erase_block_wear[i]; - for (d = 0; d < 10; ++d) - if (wear <= decile_max[d]) { - deciles[d] += 1; - break; - } - } - avg = tot / wear_eb_count; - /* Output wear report */ - NS_INFO("*** Wear Report ***\n"); - NS_INFO("Total numbers of erases: %lu\n", tot); - NS_INFO("Number of erase blocks: %u\n", wear_eb_count); - NS_INFO("Average number of erases: %lu\n", avg); - NS_INFO("Maximum number of erases: %lu\n", wmax); - NS_INFO("Minimum number of erases: %lu\n", wmin); - for (i = 0; i < 10; ++i) { - unsigned long from = (i ? decile_max[i - 1] + 1 : 0); - if (from > decile_max[i]) - continue; - NS_INFO("Number of ebs with erase counts from %lu to %lu : %lu\n", - from, - decile_max[i], - deciles[i]); - } - NS_INFO("*** End of Wear Report ***\n"); } /* @@ -2330,6 +2400,9 @@ static int __init ns_init_module(void) if ((retval = setup_wear_reporting(nsmtd)) != 0) goto err_exit; + if ((retval = nandsim_debugfs_create(nand)) != 0) + goto err_exit; + if ((retval = init_nandsim(nsmtd)) != 0) goto err_exit; @@ -2369,6 +2442,7 @@ static void __exit ns_cleanup_module(void) struct nandsim *ns = ((struct nand_chip *)nsmtd->priv)->priv; int i; + nandsim_debugfs_remove(ns); free_nandsim(ns); /* Free nandsim private resources */ nand_release(nsmtd); /* Unregister driver */ for (i = 0;i < ARRAY_SIZE(ns->partitions); ++i)