* [RFC][PATCH 2/2] efi_pstore: add a sequence counter to a variable name
@ 2012-10-05 19:02 Seiji Aguchi
2012-10-18 23:47 ` Mike Waychison
0 siblings, 1 reply; 2+ messages in thread
From: Seiji Aguchi @ 2012-10-05 19:02 UTC (permalink / raw)
To: linux-kernel, linux-acpi, linux-efi, Luck,
Tony (tony.luck@intel.com), Matthew Garrett (mjg@redhat.com),
dzickus, mikew
Cc: dle-develop, Satoru Moriya
[Problem]
Currently, a variable name, which distinguishes each entry, consists of type, id and ctime.
But if multiple events happens in a short time, a second/third event may fail to log because
efi_pstore can't distinguish each event with current variable name.
[Solution]
A reasonable way to identify all events precisely is introducing a sequence counter to
the variable name.
[Patch Description]
The sequence counter has already supported in a pstore layer with "oopscount".
So, this patch adds it to a variable name.
Also, it is passed to read/erase callbacks of platform drivers in accordance with
the modification of the variable name.
<before applying this patch>
a variable name of first event: dump-type0-1-12345678
a variable name of second event: dump-type0-1-12345678
type:0
id:1
ctime:12345678
If multiple events happen in a short time, efi_pstore can't distinguish them because
variable names are same among them.
<after applying this patch>
it can be distinguishable by adding a sequence counter as follows.
a variable name of first event: dump-type0-1-1-12345678
a variable name of Second event: dump-type0-1-2-12345678
type:0
id:1
sequence counter: 1(first event), 2(second event)
ctime:12345678
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
---
drivers/acpi/apei/erst.c | 12 ++++++------
drivers/firmware/efivars.c | 25 ++++++++++++++++---------
fs/pstore/inode.c | 8 +++++---
fs/pstore/internal.h | 2 +-
fs/pstore/platform.c | 11 ++++++-----
fs/pstore/ram.c | 7 +++----
include/linux/pstore.h | 8 +++++---
7 files changed, 42 insertions(+), 31 deletions(-)
diff --git a/drivers/acpi/apei/erst.c b/drivers/acpi/apei/erst.c
index 0bd6ae4..6d894bf 100644
--- a/drivers/acpi/apei/erst.c
+++ b/drivers/acpi/apei/erst.c
@@ -931,13 +931,13 @@ static int erst_check_table(struct acpi_table_erst *erst_tab)
static int erst_open_pstore(struct pstore_info *psi);
static int erst_close_pstore(struct pstore_info *psi);
-static ssize_t erst_reader(u64 *id, enum pstore_type_id *type,
+static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, int *count,
struct timespec *time, char **buf,
struct pstore_info *psi);
static int erst_writer(enum pstore_type_id type, enum kmsg_dump_reason reason,
- u64 *id, unsigned int part,
+ u64 *id, unsigned int part, int count,
size_t size, struct pstore_info *psi);
-static int erst_clearer(enum pstore_type_id type, u64 id,
+static int erst_clearer(enum pstore_type_id type, u64 id, int count,
struct timespec time, struct pstore_info *psi);
static struct pstore_info erst_info = {
@@ -987,7 +987,7 @@ static int erst_close_pstore(struct pstore_info *psi)
return 0;
}
-static ssize_t erst_reader(u64 *id, enum pstore_type_id *type,
+static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, int *count,
struct timespec *time, char **buf,
struct pstore_info *psi)
{
@@ -1055,7 +1055,7 @@ out:
}
static int erst_writer(enum pstore_type_id type, enum kmsg_dump_reason reason,
- u64 *id, unsigned int part,
+ u64 *id, unsigned int part, int count,
size_t size, struct pstore_info *psi)
{
struct cper_pstore_record *rcd = (struct cper_pstore_record *)
@@ -1101,7 +1101,7 @@ static int erst_writer(enum pstore_type_id type, enum kmsg_dump_reason reason,
return ret;
}
-static int erst_clearer(enum pstore_type_id type, u64 id,
+static int erst_clearer(enum pstore_type_id type, u64 id, int count,
struct timespec time, struct pstore_info *psi)
{
return erst_clear(id);
diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c
index 0eaaba3..511d6ee 100644
--- a/drivers/firmware/efivars.c
+++ b/drivers/firmware/efivars.c
@@ -658,13 +658,14 @@ static int efi_pstore_close(struct pstore_info *psi)
}
static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type,
- struct timespec *timespec,
+ int *count, struct timespec *timespec,
char **buf, struct pstore_info *psi)
{
efi_guid_t vendor = LINUX_EFI_CRASH_GUID;
struct efivars *efivars = psi->data;
char name[DUMP_NAME_LEN];
int i;
+ int cnt;
unsigned int part, size;
unsigned long time;
@@ -674,8 +675,10 @@ static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type,
for (i = 0; i < DUMP_NAME_LEN; i++) {
name[i] = efivars->walk_entry->var.VariableName[i];
}
- if (sscanf(name, "dump-type%u-%u-%lu", type, &part, &time) == 3) {
+ if (sscanf(name, "dump-type%u-%u-%d-%lu",
+ type, &part, &cnt, &time) == 4) {
*id = part;
+ *count = cnt;
timespec->tv_sec = time;
timespec->tv_nsec = 0;
get_var_data_locked(efivars, &efivars->walk_entry->var);
@@ -698,7 +701,8 @@ static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type,
static int efi_pstore_write(enum pstore_type_id type,
enum kmsg_dump_reason reason, u64 *id,
- unsigned int part, size_t size, struct pstore_info *psi)
+ unsigned int part, int count, size_t size,
+ struct pstore_info *psi)
{
char name[DUMP_NAME_LEN];
efi_char16_t efi_name[DUMP_NAME_LEN];
@@ -726,7 +730,8 @@ static int efi_pstore_write(enum pstore_type_id type,
return -ENOSPC;
}
- sprintf(name, "dump-type%u-%u-%lu", type, part, get_seconds());
+ sprintf(name, "dump-type%u-%u-%d-%lu", type, part, count,
+ get_seconds());
for (i = 0; i < DUMP_NAME_LEN; i++)
efi_name[i] = name[i];
@@ -746,7 +751,7 @@ static int efi_pstore_write(enum pstore_type_id type,
return ret;
};
-static int efi_pstore_erase(enum pstore_type_id type, u64 id,
+static int efi_pstore_erase(enum pstore_type_id type, u64 id, int count,
struct timespec time, struct pstore_info *psi)
{
char name[DUMP_NAME_LEN];
@@ -756,7 +761,8 @@ static int efi_pstore_erase(enum pstore_type_id type, u64 id,
struct efivar_entry *entry, *found = NULL;
int i;
- sprintf(name, "dump-type%u-%llu-%lu", type, id, time.tv_sec);
+ sprintf(name, "dump-type%u-%llu-%d-%lu", type, id, count,
+ time.tv_sec);
spin_lock(&efivars->lock);
@@ -806,7 +812,7 @@ static int efi_pstore_close(struct pstore_info *psi)
return 0;
}
-static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type,
+static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type, int *count,
struct timespec *timespec,
char **buf, struct pstore_info *psi)
{
@@ -815,12 +821,13 @@ static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type,
static int efi_pstore_write(enum pstore_type_id type,
enum kmsg_dump_reason reason, u64 *id,
- unsigned int part, size_t size, struct pstore_info *psi)
+ unsigned int part, int count, size_t size,
+ struct pstore_info *psi)
{
return 0;
}
-static int efi_pstore_erase(enum pstore_type_id type, u64 id,
+static int efi_pstore_erase(enum pstore_type_id type, u64 id, int count,
struct timespec time, struct pstore_info *psi)
{
return 0;
diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c
index 4300af6..ed1d8c7 100644
--- a/fs/pstore/inode.c
+++ b/fs/pstore/inode.c
@@ -49,6 +49,7 @@ struct pstore_private {
struct pstore_info *psi;
enum pstore_type_id type;
u64 id;
+ int count;
ssize_t size;
char data[];
};
@@ -175,8 +176,8 @@ static int pstore_unlink(struct inode *dir, struct dentry *dentry)
struct pstore_private *p = dentry->d_inode->i_private;
if (p->psi->erase)
- p->psi->erase(p->type, p->id, dentry->d_inode->i_ctime,
- p->psi);
+ p->psi->erase(p->type, p->id, p->count,
+ dentry->d_inode->i_ctime, p->psi);
return simple_unlink(dir, dentry);
}
@@ -271,7 +272,7 @@ int pstore_is_mounted(void)
* Load it up with "size" bytes of data from "buf".
* Set the mtime & ctime to the date that this record was originally stored.
*/
-int pstore_mkfile(enum pstore_type_id type, char *psname, u64 id,
+int pstore_mkfile(enum pstore_type_id type, char *psname, u64 id, int count,
char *data, size_t size, struct timespec time,
struct pstore_info *psi)
{
@@ -307,6 +308,7 @@ int pstore_mkfile(enum pstore_type_id type, char *psname, u64 id,
goto fail_alloc;
private->type = type;
private->id = id;
+ private->count = count;
private->psi = psi;
switch (type) {
diff --git a/fs/pstore/internal.h b/fs/pstore/internal.h
index 0d0d3b7..e170a66 100644
--- a/fs/pstore/internal.h
+++ b/fs/pstore/internal.h
@@ -44,7 +44,7 @@ extern struct pstore_info *psinfo;
extern void pstore_set_kmsg_bytes(int);
extern void pstore_get_records(int);
extern int pstore_mkfile(enum pstore_type_id, char *psname, u64 id,
- char *data, size_t size,
+ int count, char *data, size_t size,
struct timespec time, struct pstore_info *psi);
extern int pstore_is_mounted(void);
diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index 29996e8..5a07c9e 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -136,7 +136,7 @@ static void pstore_dump(struct kmsg_dumper *dumper,
break;
ret = psinfo->write(PSTORE_TYPE_DMESG, reason, &id, part,
- hsize + len, psinfo);
+ oopscount, hsize + len, psinfo);
if (ret == 0 && reason == KMSG_DUMP_OOPS && pstore_is_mounted())
pstore_new_entry = 1;
@@ -190,7 +190,7 @@ static void pstore_register_console(void) {}
static int pstore_write_compat(enum pstore_type_id type,
enum kmsg_dump_reason reason,
- u64 *id, unsigned int part,
+ u64 *id, unsigned int part, int count,
size_t size, struct pstore_info *psi)
{
return psi->write_buf(type, reason, id, part, psinfo->buf, size, psi);
@@ -259,6 +259,7 @@ void pstore_get_records(int quiet)
char *buf = NULL;
ssize_t size;
u64 id;
+ int count;
enum pstore_type_id type;
struct timespec time;
int failed = 0, rc;
@@ -270,9 +271,9 @@ void pstore_get_records(int quiet)
if (psi->open && psi->open(psi))
goto out;
- while ((size = psi->read(&id, &type, &time, &buf, psi)) > 0) {
- rc = pstore_mkfile(type, psi->name, id, buf, (size_t)size,
- time, psi);
+ while ((size = psi->read(&id, &type, &count, &time, &buf, psi)) > 0) {
+ rc = pstore_mkfile(type, psi->name, id, count, buf,
+ (size_t)size, time, psi);
kfree(buf);
buf = NULL;
if (rc && (rc != -EEXIST || !quiet))
diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c
index 177b281..403a5fc 100644
--- a/fs/pstore/ram.c
+++ b/fs/pstore/ram.c
@@ -131,9 +131,8 @@ ramoops_get_next_prz(struct persistent_ram_zone *przs[], uint *c, uint max,
}
static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type,
- struct timespec *time,
- char **buf,
- struct pstore_info *psi)
+ int *count, struct timespec *time,
+ char **buf, struct pstore_info *psi)
{
ssize_t size;
struct ramoops_context *cxt = psi->data;
@@ -236,7 +235,7 @@ static int ramoops_pstore_write_buf(enum pstore_type_id type,
return 0;
}
-static int ramoops_pstore_erase(enum pstore_type_id type, u64 id,
+static int ramoops_pstore_erase(enum pstore_type_id type, u64 id, int count,
timespec time, struct pstore_info *psi)
{
struct ramoops_context *cxt = psi->data;
diff --git a/include/linux/pstore.h b/include/linux/pstore.h
index 71f43e0..c768758 100644
--- a/include/linux/pstore.h
+++ b/include/linux/pstore.h
@@ -50,17 +50,19 @@ struct pstore_info {
int (*open)(struct pstore_info *psi);
int (*close)(struct pstore_info *psi);
ssize_t (*read)(u64 *id, enum pstore_type_id *type,
- struct timespec *time, char **buf,
+ int *count, struct timespec *time, char **buf,
struct pstore_info *psi);
int (*write)(enum pstore_type_id type,
enum kmsg_dump_reason reason, u64 *id,
- unsigned int part, size_t size, struct pstore_info *psi);
+ unsigned int part, int count, size_t size,
+ struct pstore_info *psi);
int (*write_buf)(enum pstore_type_id type,
enum kmsg_dump_reason reason, u64 *id,
unsigned int part, const char *buf, size_t size,
struct pstore_info *psi);
int (*erase)(enum pstore_type_id type, u64 id,
- struct timespec time, struct pstore_info *psi);
+ int count, struct timespec time,
+ struct pstore_info *psi);
void *data;
};
-- 1.7.1
^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [RFC][PATCH 2/2] efi_pstore: add a sequence counter to a variable name
2012-10-05 19:02 [RFC][PATCH 2/2] efi_pstore: add a sequence counter to a variable name Seiji Aguchi
@ 2012-10-18 23:47 ` Mike Waychison
0 siblings, 0 replies; 2+ messages in thread
From: Mike Waychison @ 2012-10-18 23:47 UTC (permalink / raw)
To: Seiji Aguchi
Cc: linux-kernel, linux-acpi, linux-efi, Luck,
Tony (tony.luck@intel.com), Matthew Garrett (mjg@redhat.com),
dzickus, dle-develop, Satoru Moriya
On Fri, Oct 5, 2012 at 12:02 PM, Seiji Aguchi <seiji.aguchi@hds.com> wrote:
> [Problem]
>
> Currently, a variable name, which distinguishes each entry, consists of type, id and ctime.
> But if multiple events happens in a short time, a second/third event may fail to log because
> efi_pstore can't distinguish each event with current variable name.
>
> [Solution]
>
> A reasonable way to identify all events precisely is introducing a sequence counter to
> the variable name.
>
> [Patch Description]
>
> The sequence counter has already supported in a pstore layer with "oopscount".
> So, this patch adds it to a variable name.
> Also, it is passed to read/erase callbacks of platform drivers in accordance with
> the modification of the variable name.
>
> <before applying this patch>
> a variable name of first event: dump-type0-1-12345678
> a variable name of second event: dump-type0-1-12345678
>
> type:0
> id:1
> ctime:12345678
>
> If multiple events happen in a short time, efi_pstore can't distinguish them because
> variable names are same among them.
>
> <after applying this patch>
>
> it can be distinguishable by adding a sequence counter as follows.
>
> a variable name of first event: dump-type0-1-1-12345678
> a variable name of Second event: dump-type0-1-2-12345678
>
> type:0
> id:1
> sequence counter: 1(first event), 2(second event)
> ctime:12345678
This patch plumbs the count through the same way as you plumbed the
ctime through in patch 1/2, so I'm going to hold off on commenting on
this patch until we better understand i_ctime use is resolved there.
I suspect that we don't want to continue adding more arguments through
pstore ops this way.
^ permalink raw reply [flat|nested] 2+ messages in thread
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