On 2023/9/5 16:29, Baoquan He wrote:
> On 09/04/23 at 10:47am, Leizhen (ThunderTown) wrote:
>>
>>
>> On 2023/9/1 17:49, Baoquan He wrote:
>>>>> +
>>>>> + *high = true;
>>>>> + } else if (ret || !*crash_size) {
>>>> This check can be moved outside of #ifdef. Because even '!high', it's
>>>> completely
>>>> applicable. The overall adjustment is as follows:
>>> Hmm, the current logic is much easier to understand. However, I may not
>>> 100% get your suggestion. Can you paste the complete code in your
>>> suggested way? Do not need 100% correct code, just the skeleton of code
>>> logic
>>> so that I can better understand it and add inline comment.
>>
>> int __init parse_crashkernel(...)
>> {
>> int ret;
>>
>> /* crashkernel=X[@offset] */
>> ret = __parse_crashkernel(cmdline, system_ram, crash_size,
>> crash_base, NULL);
>>
>> #ifdef CONFIG_ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
>> if (high && ret == -ENOENT) {
>> ... ... //The code for your original branch "else if
>> (ret == -ENOENT) {"
>> ret = 0; //Added based on the next discussion
>> }
>> +#endif
>>
>> if (!*crash_size)
>> ret = -EINVAL;
>>
>> return ret;
>> }
>>
> Thanks, Zhen Lei.
>
> I paste the whole parse_crashkernel() as you suggested at bottom. Please
> check if it's what you want.
Yes.
> To me, both is fine to me. I have two minor
> concerns to your suggested way.
>
> 1)
> I took the "if (!high) return" way because except of x86/arm64, all
> other architectures will call parse_crashkerne() and check
> if *crash_size ==0. Please try 'git grep "parse_crashkernel(" arch'
> and check those call sites. With that, we will have duplicated checking.
Add some patches to remove the duplicated checking of other ARCHs? After this
patch series upstreamed.
>
> ret = __parse_crashkernel(cmdline, system_ram, crash_size,
> crash_base, NULL);
> if (!high)
> return ret;
> 2)
> I actually like below branch and the code comment. It can give people
> hint about what's going on in that case. Discarding it is a little pity.
Except that "!*crash_size" and "(high && ret == -ENOENT)" needs special
comments,
other common errors do not need to be described, I think. Even if some is
required,
it should be placed in function __parse_crashkernel().
>
> } else if (ret || !*crash_size) {
> /* The specified value is invalid */
> return -1;
> }
>
> int __init parse_crashkernel(...)
> {
> int ret;
>
> /* crashkernel=X[@offset] */
> ret = __parse_crashkernel(cmdline, system_ram, crash_size,
> crash_base, NULL);
> #ifdef CONFIG_ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
> if (high && ret == -ENOENT) {
> ret = __parse_crashkernel(cmdline, 0, crash_size,
> crash_base, suffix_tbl[SUFFIX_HIGH]);
> if (ret || !*crash_size)
> return -EINVAL;
>
> /*
> * crashkernel=Y,low can be specified or not, but invalid value
> * is not allowed.
> */
> ret = __parse_crashkernel(cmdline, 0, low_size,
> crash_base, suffix_tbl[SUFFIX_LOW]);
> if (ret == -ENOENT) {
> *low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE;
> ret = 0;
> } else if (ret) {
> return ret;
> }
>
> *high = true;
> }
> #endif
>
> if (!*crash_size)
> ret = -EINVAL;
>
> return ret;
> }
>
> .
>
--
Regards,
Zhen Lei
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