[MTD] nandsim: Enhance nandsim optionally to report wear information

A new module parameter 'rptwear' specifies how many erases between
reporting wear information.  Zero means never.

Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
This commit is contained in:
Adrian Hunter 2007-03-19 12:40:41 +02:00 committed by David Woodhouse
parent 514087e74f
commit 57aa6b545f
1 changed files with 99 additions and 0 deletions

View File

@ -99,6 +99,7 @@ static char *weakblocks = NULL;
static char *weakpages = NULL;
static unsigned int bitflips = 0;
static char *gravepages = NULL;
static unsigned int rptwear = 0;
module_param(first_id_byte, uint, 0400);
module_param(second_id_byte, uint, 0400);
@ -119,6 +120,7 @@ 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_PARM_DESC(first_id_byte, "The fist byte returned by NAND Flash 'read ID' command (manufaturer ID)");
MODULE_PARM_DESC(second_id_byte, "The second byte returned by NAND Flash 'read ID' command (chip ID)");
@ -146,6 +148,7 @@ 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 inbetween reporting wear, if not zero");
/* The largest possible page size */
#define NS_LARGEST_PAGE_SIZE 2048
@ -162,6 +165,8 @@ MODULE_PARM_DESC(gravepages, "Pages that lose data [: maximum reads (default
do { printk(KERN_WARNING NS_OUTPUT_PREFIX " warning: " args); } while(0)
#define NS_ERR(args...) \
do { printk(KERN_ERR NS_OUTPUT_PREFIX " error: " args); } while(0)
#define NS_INFO(args...) \
do { printk(KERN_INFO NS_OUTPUT_PREFIX " " args); } while(0)
/* Busy-wait delay macros (microseconds, milliseconds) */
#define NS_UDELAY(us) \
@ -394,6 +399,11 @@ struct grave_page {
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;
@ -801,6 +811,89 @@ static void free_lists(void)
list_del(pos);
kfree(list_entry(pos, struct grave_page, list));
}
kfree(erase_block_wear);
}
static int setup_wear_reporting(struct mtd_info *mtd)
{
size_t mem;
if (!rptwear)
return 0;
wear_eb_count = mtd->size / mtd->erasesize;
mem = wear_eb_count * sizeof(unsigned long);
if (mem / sizeof(unsigned long) != wear_eb_count) {
NS_ERR("Too many erase blocks for wear reporting\n");
return -ENOMEM;
}
erase_block_wear = kzalloc(mem, GFP_KERNEL);
if (!erase_block_wear) {
NS_ERR("Too many erase blocks for wear reporting\n");
return -ENOMEM;
}
return 0;
}
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;
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");
}
/*
@ -1268,6 +1361,9 @@ static int do_state_action(struct nandsim *ns, uint32_t action)
NS_MDELAY(erase_delay);
if (erase_block_wear)
update_wear(erase_block_no);
if (erase_error(erase_block_no)) {
NS_WARN("simulating erase failure in erase block %u\n", erase_block_no);
return -1;
@ -1903,6 +1999,9 @@ static int __init ns_init_module(void)
goto error;
}
if ((retval = setup_wear_reporting(nsmtd)) != 0)
goto err_exit;
if ((retval = init_nandsim(nsmtd)) != 0)
goto err_exit;