diff options
author | Huang Ying <ying.huang@intel.com> | 2011-02-21 05:54:41 (GMT) |
---|---|---|
committer | Len Brown <len.brown@intel.com> | 2011-03-22 02:59:06 (GMT) |
commit | 885b976fada5bc6595a9fd3e67e3cb1a3d11f50b (patch) | |
tree | 8b598bd3b265c0bbe8237e129410fdc80fe7847a /arch | |
parent | dd9c1549edef02290edced639f67b54a25abbe0e (diff) | |
download | linux-fsl-qoriq-885b976fada5bc6595a9fd3e67e3cb1a3d11f50b.tar.xz |
ACPI, APEI, Add ERST record ID cache
APEI ERST firmware interface and implementation has no multiple users
in mind. For example, if there is four records in storage with ID: 1,
2, 3 and 4, if two ERST readers enumerate the records via
GET_NEXT_RECORD_ID as follow,
reader 1 reader 2
1
2
3
4
-1
-1
where -1 signals there is no more record ID.
Reader 1 has no chance to check record 2 and 4, while reader 2 has no
chance to check record 1 and 3. And any other GET_NEXT_RECORD_ID will
return -1, that is, other readers will has no chance to check any
record even they are not cleared by anyone.
This makes raw GET_NEXT_RECORD_ID not suitable for used by multiple
users.
To solve the issue, an in-memory ERST record ID cache is designed and
implemented. When enumerating record ID, the ID returned by
GET_NEXT_RECORD_ID is added into cache in addition to be returned to
caller. So other readers can check the cache to get all record ID
available.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/x86/kernel/cpu/mcheck/mce-apei.c | 42 |
1 files changed, 26 insertions, 16 deletions
diff --git a/arch/x86/kernel/cpu/mcheck/mce-apei.c b/arch/x86/kernel/cpu/mcheck/mce-apei.c index 8209472..83930de 100644 --- a/arch/x86/kernel/cpu/mcheck/mce-apei.c +++ b/arch/x86/kernel/cpu/mcheck/mce-apei.c @@ -106,24 +106,34 @@ int apei_write_mce(struct mce *m) ssize_t apei_read_mce(struct mce *m, u64 *record_id) { struct cper_mce_record rcd; - ssize_t len; - - len = erst_read_next(&rcd.hdr, sizeof(rcd)); - if (len <= 0) - return len; - /* Can not skip other records in storage via ERST unless clear them */ - else if (len != sizeof(rcd) || - uuid_le_cmp(rcd.hdr.creator_id, CPER_CREATOR_MCE)) { - if (printk_ratelimit()) - pr_warning( - "MCE-APEI: Can not skip the unknown record in ERST"); - return -EIO; - } - + int rc, pos; + + rc = erst_get_record_id_begin(&pos); + if (rc) + return rc; +retry: + rc = erst_get_record_id_next(&pos, record_id); + if (rc) + goto out; + /* no more record */ + if (*record_id == APEI_ERST_INVALID_RECORD_ID) + goto out; + rc = erst_read(*record_id, &rcd.hdr, sizeof(rcd)); + /* someone else has cleared the record, try next one */ + if (rc == -ENOENT) + goto retry; + else if (rc < 0) + goto out; + /* try to skip other type records in storage */ + else if (rc != sizeof(rcd) || + uuid_le_cmp(rcd.hdr.creator_id, CPER_CREATOR_MCE)) + goto retry; memcpy(m, &rcd.mce, sizeof(*m)); - *record_id = rcd.hdr.record_id; + rc = sizeof(*m); +out: + erst_get_record_id_end(); - return sizeof(*m); + return rc; } /* Check whether there is record in ERST */ |