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 --- include/linux/pstore.h | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'include/linux/pstore.h') diff --git a/include/linux/pstore.h b/include/linux/pstore.h index f6e93362d259..1788909d9a99 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; }; -- cgit