[3/3] mm: memory-failure: make action_result() return int
Commit Message
Check mf_result in action_result(), only return 0 when MF_RECOVERED,
or return -EBUSY, which will simplify code a bit.
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
---
mm/memory-failure.c | 42 ++++++++++++++++--------------------------
1 file changed, 16 insertions(+), 26 deletions(-)
Comments
On Fri, Oct 21, 2022 at 04:46:11PM +0800, Kefeng Wang wrote:
> Check mf_result in action_result(), only return 0 when MF_RECOVERED,
> or return -EBUSY, which will simplify code a bit.
>
> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Thanks for the cleanup, Kefeng.
I basically agree with the change. I have one comment below ...
> ---
> mm/memory-failure.c | 42 ++++++++++++++++--------------------------
> 1 file changed, 16 insertions(+), 26 deletions(-)
>
> diff --git a/mm/memory-failure.c b/mm/memory-failure.c
> index ca0199d0f79d..3f469e2da047 100644
> --- a/mm/memory-failure.c
> +++ b/mm/memory-failure.c
> @@ -1182,14 +1182,16 @@ static struct page_state error_states[] = {
> * "Dirty/Clean" indication is not 100% accurate due to the possibility of
> * setting PG_dirty outside page lock. See also comment above set_page_dirty().
> */
> -static void action_result(unsigned long pfn, enum mf_action_page_type type,
> - enum mf_result result)
> +static int action_result(unsigned long pfn, enum mf_action_page_type type,
> + enum mf_result result)
> {
> trace_memory_failure_event(pfn, type, result);
>
> num_poisoned_pages_inc();
> pr_err("%#lx: recovery action for %s: %s\n",
> pfn, action_page_types[type], action_name[result]);
> +
> + return result == MF_RECOVERED ? 0 : -EBUSY;
I think that MF_DELAYED may be considered as success (returning 0), then
page_action() can be cleaned up a little more (like below?)
static int page_action(struct page_state *ps, struct page *p,
unsigned long pfn)
{
int result;
/* page p should be unlocked after returning from ps->action(). */
result = ps->action(ps, p);
/* Could do more checks here if page looks ok */
/*
* Could adjust zone counters here to correct for the missing page.
*/
return action_result(pfn, ps->type, result);
}
Existing direct callers (I mean action_result() called from other than
page_action()) are never called with result==MF_DELAYED, so this change
should not affect them.
Does it make sense for you?
Thanks,
Naoya Horiguchi
On 2022/10/24 7:56, HORIGUCHI NAOYA(堀口 直也) wrote:
> On Fri, Oct 21, 2022 at 04:46:11PM +0800, Kefeng Wang wrote:
>> Check mf_result in action_result(), only return 0 when MF_RECOVERED,
>> or return -EBUSY, which will simplify code a bit.
>>
>> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
> Thanks for the cleanup, Kefeng.
> I basically agree with the change. I have one comment below ...
>
>> ---
>> mm/memory-failure.c | 42 ++++++++++++++++--------------------------
>> 1 file changed, 16 insertions(+), 26 deletions(-)
>>
>> diff --git a/mm/memory-failure.c b/mm/memory-failure.c
>> index ca0199d0f79d..3f469e2da047 100644
>> --- a/mm/memory-failure.c
>> +++ b/mm/memory-failure.c
>> @@ -1182,14 +1182,16 @@ static struct page_state error_states[] = {
>> * "Dirty/Clean" indication is not 100% accurate due to the possibility of
>> * setting PG_dirty outside page lock. See also comment above set_page_dirty().
>> */
>> -static void action_result(unsigned long pfn, enum mf_action_page_type type,
>> - enum mf_result result)
>> +static int action_result(unsigned long pfn, enum mf_action_page_type type,
>> + enum mf_result result)
>> {
>> trace_memory_failure_event(pfn, type, result);
>>
>> num_poisoned_pages_inc();
>> pr_err("%#lx: recovery action for %s: %s\n",
>> pfn, action_page_types[type], action_name[result]);
>> +
>> + return result == MF_RECOVERED ? 0 : -EBUSY;
> I think that MF_DELAYED may be considered as success (returning 0), then
> page_action() can be cleaned up a little more (like below?)
Yes, MF_DELAYED should be considered as success,
>
> static int page_action(struct page_state *ps, struct page *p,
> unsigned long pfn)
> {
> int result;
>
> /* page p should be unlocked after returning from ps->action(). */
> result = ps->action(ps, p);
>
> /* Could do more checks here if page looks ok */
> /*
> * Could adjust zone counters here to correct for the missing page.
> */
>
> return action_result(pfn, ps->type, result);
> }
>
> Existing direct callers (I mean action_result() called from other than
> page_action()) are never called with result==MF_DELAYED, so this change
> should not affect them.
I will refresh this patch, thanks.
> Does it make sense for you?
>
> Thanks,
> Naoya Horiguchi
@@ -1182,14 +1182,16 @@ static struct page_state error_states[] = {
* "Dirty/Clean" indication is not 100% accurate due to the possibility of
* setting PG_dirty outside page lock. See also comment above set_page_dirty().
*/
-static void action_result(unsigned long pfn, enum mf_action_page_type type,
- enum mf_result result)
+static int action_result(unsigned long pfn, enum mf_action_page_type type,
+ enum mf_result result)
{
trace_memory_failure_event(pfn, type, result);
num_poisoned_pages_inc();
pr_err("%#lx: recovery action for %s: %s\n",
pfn, action_page_types[type], action_name[result]);
+
+ return result == MF_RECOVERED ? 0 : -EBUSY;
}
static int page_action(struct page_state *ps, struct page *p,
@@ -1856,8 +1858,7 @@ static int try_memory_failure_hugetlb(unsigned long pfn, int flags, int *hugetlb
flags |= MF_NO_RETRY;
goto retry;
}
- action_result(pfn, MF_MSG_UNKNOWN, MF_IGNORED);
- return res;
+ return action_result(pfn, MF_MSG_UNKNOWN, MF_IGNORED);
}
head = compound_head(p);
@@ -1883,22 +1884,18 @@ static int try_memory_failure_hugetlb(unsigned long pfn, int flags, int *hugetlb
} else {
res = MF_FAILED;
}
- action_result(pfn, MF_MSG_FREE_HUGE, res);
- return res == MF_RECOVERED ? 0 : -EBUSY;
+ return action_result(pfn, MF_MSG_FREE_HUGE, res);
}
page_flags = head->flags;
if (!hwpoison_user_mappings(p, pfn, flags, head)) {
- action_result(pfn, MF_MSG_UNMAP_FAILED, MF_IGNORED);
- res = -EBUSY;
- goto out;
+ res = action_result(pfn, MF_MSG_UNMAP_FAILED, MF_IGNORED);
+ unlock_page(head);
+ return res;
}
return identify_page_state(pfn, p, page_flags);
-out:
- unlock_page(head);
- return res;
}
#else
@@ -2063,16 +2060,13 @@ int memory_failure(unsigned long pfn, int flags)
}
res = MF_FAILED;
}
- action_result(pfn, MF_MSG_BUDDY, res);
- res = res == MF_RECOVERED ? 0 : -EBUSY;
+ res = action_result(pfn, MF_MSG_BUDDY, res);
} else {
- action_result(pfn, MF_MSG_KERNEL_HIGH_ORDER, MF_IGNORED);
- res = -EBUSY;
+ res = action_result(pfn, MF_MSG_KERNEL_HIGH_ORDER, MF_IGNORED);
}
goto unlock_mutex;
} else if (res < 0) {
- action_result(pfn, MF_MSG_UNKNOWN, MF_IGNORED);
- res = -EBUSY;
+ res = action_result(pfn, MF_MSG_UNKNOWN, MF_IGNORED);
goto unlock_mutex;
}
}
@@ -2093,8 +2087,7 @@ int memory_failure(unsigned long pfn, int flags)
*/
SetPageHasHWPoisoned(hpage);
if (try_to_split_thp_page(p) < 0) {
- action_result(pfn, MF_MSG_UNSPLIT_THP, MF_IGNORED);
- res = -EBUSY;
+ res = action_result(pfn, MF_MSG_UNSPLIT_THP, MF_IGNORED);
goto unlock_mutex;
}
VM_BUG_ON_PAGE(!page_count(p), p);
@@ -2127,8 +2120,7 @@ int memory_failure(unsigned long pfn, int flags)
retry = false;
goto try_again;
}
- action_result(pfn, MF_MSG_DIFFERENT_COMPOUND, MF_IGNORED);
- res = -EBUSY;
+ res = action_result(pfn, MF_MSG_DIFFERENT_COMPOUND, MF_IGNORED);
goto unlock_page;
}
@@ -2168,8 +2160,7 @@ int memory_failure(unsigned long pfn, int flags)
* Abort on fail: __filemap_remove_folio() assumes unmapped page.
*/
if (!hwpoison_user_mappings(p, pfn, flags, p)) {
- action_result(pfn, MF_MSG_UNMAP_FAILED, MF_IGNORED);
- res = -EBUSY;
+ res = action_result(pfn, MF_MSG_UNMAP_FAILED, MF_IGNORED);
goto unlock_page;
}
@@ -2177,8 +2168,7 @@ int memory_failure(unsigned long pfn, int flags)
* Torn down by someone else?
*/
if (PageLRU(p) && !PageSwapCache(p) && p->mapping == NULL) {
- action_result(pfn, MF_MSG_TRUNCATED_LRU, MF_IGNORED);
- res = -EBUSY;
+ res = action_result(pfn, MF_MSG_TRUNCATED_LRU, MF_IGNORED);
goto unlock_page;
}