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| author | Borislav Petkov <bp@suse.de> | 2019-04-20 14:06:37 +0200 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2019-06-08 17:33:10 +0200 |
| commit | de0e0624d86ff9fc512dedb297f8978698abf21a (patch) | |
| tree | 28d6d96ec9e4765a65a096cf1e26d0611e929193 /drivers/ras | |
| parent | 6d8e294bf5f0e85c34e8b14b064e2965f53f38b0 (diff) | |
| download | lwn-de0e0624d86ff9fc512dedb297f8978698abf21a.tar.gz lwn-de0e0624d86ff9fc512dedb297f8978698abf21a.zip | |
RAS/CEC: Check count_threshold unconditionally
The count_threshold should be checked unconditionally, after insertion
too, so that a count_threshold value of 1 can cause an immediate
offlining. I.e., offline the page on the *first* error encountered.
Add comments to make it clear what cec_add_elem() does, while at it.
Reported-by: WANG Chao <chao.wang@ucloud.cn>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-edac@vger.kernel.org
Link: https://lkml.kernel.org/r/20190418034115.75954-3-chao.wang@ucloud.cn
Diffstat (limited to 'drivers/ras')
| -rw-r--r-- | drivers/ras/cec.c | 27 |
1 files changed, 10 insertions, 17 deletions
diff --git a/drivers/ras/cec.c b/drivers/ras/cec.c index f5795adc5a6e..73a975c26f9f 100644 --- a/drivers/ras/cec.c +++ b/drivers/ras/cec.c @@ -294,6 +294,7 @@ int cec_add_elem(u64 pfn) ca->ces_entered++; + /* Array full, free the LRU slot. */ if (ca->n == MAX_ELEMS) WARN_ON(!del_lru_elem_unlocked(ca)); @@ -306,24 +307,17 @@ int cec_add_elem(u64 pfn) (void *)&ca->array[to], (ca->n - to) * sizeof(u64)); - ca->array[to] = (pfn << PAGE_SHIFT) | - (DECAY_MASK << COUNT_BITS) | 1; - + ca->array[to] = pfn << PAGE_SHIFT; ca->n++; - - ret = 0; - - goto decay; } - count = COUNT(ca->array[to]); - - if (count < count_threshold) { - ca->array[to] |= (DECAY_MASK << COUNT_BITS); - ca->array[to]++; + /* Add/refresh element generation and increment count */ + ca->array[to] |= DECAY_MASK << COUNT_BITS; + ca->array[to]++; - ret = 0; - } else { + /* Check action threshold and soft-offline, if reached. */ + count = COUNT(ca->array[to]); + if (count >= count_threshold) { u64 pfn = ca->array[to] >> PAGE_SHIFT; if (!pfn_valid(pfn)) { @@ -338,15 +332,14 @@ int cec_add_elem(u64 pfn) del_elem(ca, to); /* - * Return a >0 value to denote that we've reached the offlining - * threshold. + * Return a >0 value to callers, to denote that we've reached + * the offlining threshold. */ ret = 1; goto unlock; } -decay: ca->decay_count++; if (ca->decay_count >= CLEAN_ELEMS) |