diff options
Diffstat (limited to 'fs/pstore/platform.c')
| -rw-r--r-- | fs/pstore/platform.c | 93 |
1 files changed, 72 insertions, 21 deletions
diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index c5300ec3169..2bd620f0d79 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -25,12 +25,30 @@ #include <linux/module.h> #include <linux/pstore.h> #include <linux/string.h> +#include <linux/timer.h> #include <linux/slab.h> #include <linux/uaccess.h> +#include <linux/hardirq.h> +#include <linux/workqueue.h> #include "internal.h" /* + * We defer making "oops" entries appear in pstore - see + * whether the system is actually still running well enough + * to let someone see the entry + */ +#define PSTORE_INTERVAL (60 * HZ) + +static int pstore_new_entry; + +static void pstore_timefunc(unsigned long); +static DEFINE_TIMER(pstore_timer, pstore_timefunc, 0, 0); + +static void pstore_dowork(struct work_struct *); +static DECLARE_WORK(pstore_work, pstore_dowork); + +/* * pstore_lock just protects "psinfo" during * calls to pstore_register() */ @@ -69,15 +87,22 @@ static void pstore_dump(struct kmsg_dumper *dumper, unsigned long size, total = 0; char *dst, *why; u64 id; - int hsize; + int hsize, ret; unsigned int part = 1; + unsigned long flags = 0; + int is_locked = 0; if (reason < ARRAY_SIZE(reason_str)) why = reason_str[reason]; else why = "Unknown"; - mutex_lock(&psinfo->buf_mutex); + if (in_nmi()) { + is_locked = spin_trylock(&psinfo->buf_lock); + if (!is_locked) + pr_err("pstore dump routine blocked in NMI, may corrupt error record\n"); + } else + spin_lock_irqsave(&psinfo->buf_lock, flags); oopscount++; while (total < kmsg_bytes) { dst = psinfo->buf; @@ -97,18 +122,20 @@ static void pstore_dump(struct kmsg_dumper *dumper, memcpy(dst, s1 + s1_start, l1_cpy); memcpy(dst + l1_cpy, s2 + s2_start, l2_cpy); - id = psinfo->write(PSTORE_TYPE_DMESG, part, + ret = psinfo->write(PSTORE_TYPE_DMESG, &id, part, hsize + l1_cpy + l2_cpy, psinfo); - if (reason == KMSG_DUMP_OOPS && pstore_is_mounted()) - pstore_mkfile(PSTORE_TYPE_DMESG, psinfo->name, id, - psinfo->buf, hsize + l1_cpy + l2_cpy, - CURRENT_TIME, psinfo); + if (ret == 0 && reason == KMSG_DUMP_OOPS && pstore_is_mounted()) + pstore_new_entry = 1; l1 -= l1_cpy; l2 -= l2_cpy; total += l1_cpy + l2_cpy; part++; } - mutex_unlock(&psinfo->buf_mutex); + if (in_nmi()) { + if (is_locked) + spin_unlock(&psinfo->buf_lock); + } else + spin_unlock_irqrestore(&psinfo->buf_lock, flags); } static struct kmsg_dumper pstore_dumper = { @@ -148,19 +175,24 @@ int pstore_register(struct pstore_info *psi) } if (pstore_is_mounted()) - pstore_get_records(); + pstore_get_records(0); kmsg_dump_register(&pstore_dumper); + pstore_timer.expires = jiffies + PSTORE_INTERVAL; + add_timer(&pstore_timer); + return 0; } EXPORT_SYMBOL_GPL(pstore_register); /* - * Read all the records from the persistent store. Create and - * file files in our filesystem. + * Read all the records from the persistent store. Create + * files in our filesystem. Don't warn about -EEXIST errors + * when we are re-scanning the backing store looking to add new + * error records. */ -void pstore_get_records(void) +void pstore_get_records(int quiet) { struct pstore_info *psi = psinfo; ssize_t size; @@ -168,36 +200,55 @@ void pstore_get_records(void) enum pstore_type_id type; struct timespec time; int failed = 0, rc; + unsigned long flags; if (!psi) return; - mutex_lock(&psinfo->buf_mutex); + spin_lock_irqsave(&psinfo->buf_lock, flags); rc = psi->open(psi); if (rc) goto out; while ((size = psi->read(&id, &type, &time, psi)) > 0) { - if (pstore_mkfile(type, psi->name, id, psi->buf, (size_t)size, - time, psi)) + rc = pstore_mkfile(type, psi->name, id, psi->buf, (size_t)size, + time, psi); + if (rc && (rc != -EEXIST || !quiet)) failed++; } psi->close(psi); out: - mutex_unlock(&psinfo->buf_mutex); + spin_unlock_irqrestore(&psinfo->buf_lock, flags); if (failed) printk(KERN_WARNING "pstore: failed to load %d record(s) from '%s'\n", failed, psi->name); } +static void pstore_dowork(struct work_struct *work) +{ + pstore_get_records(1); +} + +static void pstore_timefunc(unsigned long dummy) +{ + if (pstore_new_entry) { + pstore_new_entry = 0; + schedule_work(&pstore_work); + } + + mod_timer(&pstore_timer, jiffies + PSTORE_INTERVAL); +} + /* * Call platform driver to write a record to the * persistent store. */ int pstore_write(enum pstore_type_id type, char *buf, size_t size) { - u64 id; + u64 id; + int ret; + unsigned long flags; if (!psinfo) return -ENODEV; @@ -205,13 +256,13 @@ int pstore_write(enum pstore_type_id type, char *buf, size_t size) if (size > psinfo->bufsize) return -EFBIG; - mutex_lock(&psinfo->buf_mutex); + spin_lock_irqsave(&psinfo->buf_lock, flags); memcpy(psinfo->buf, buf, size); - id = psinfo->write(type, 0, size, psinfo); - if (pstore_is_mounted()) + ret = psinfo->write(type, &id, 0, size, psinfo); + if (ret == 0 && pstore_is_mounted()) pstore_mkfile(PSTORE_TYPE_DMESG, psinfo->name, id, psinfo->buf, size, CURRENT_TIME, psinfo); - mutex_unlock(&psinfo->buf_mutex); + spin_unlock_irqrestore(&psinfo->buf_lock, flags); return 0; } |