From 755d4fe46529018ae45bc7c86df682de45ace764 Mon Sep 17 00:00:00 2001 From: Seiji Aguchi Date: Mon, 26 Nov 2012 16:07:44 -0800 Subject: efi_pstore: Add a sequence counter to a variable name [Issue] Currently, a variable name, which identifies 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. 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. 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. 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 In case of a write callback executed in pstore_console_write(), "0" is added to an argument of the write callback because it just logs all kernel messages and doesn't need to care about multiple events. Signed-off-by: Seiji Aguchi Acked-by: Rafael J. Wysocki Acked-by: Mike Waychison Signed-off-by: Tony Luck --- drivers/acpi/apei/erst.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/apei/erst.c b/drivers/acpi/apei/erst.c index 0bd6ae4a899f..6d894bfd8b8f 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); -- cgit v1.2.3