RFR: 8357086: os::xxx functions returning memory size should return size_t

[Stefan Karlsson]

On Wed, 28 May 2025 09:47:39 GMT, Stefan Karlsson <stefank at openjdk.org> wrote:

>> Hi,
>> 
>> in this PR the output value type for functions which return memory are changed, namely:
>> 
>> 
>> static julong available_memory(); --> static size_t available_memory();
>> static julong used_memory(); --> static size_t used_memory();
>> static julong free_memory(); --> static size_t free_memory(); 
>> static jlong total_swap_space(); --> static size_t total_swap_space();
>> static jlong free_swap_space(); --> static size_t free_swap_space(); 
>> static julong physical_memory(); --> static size_t physical_memory(); 
>> 
>> 
>> The changes are done so that the other parts of the code have minimal impact. 
>> Tested in GHA and Tiers 1-4.
>> 
>> ---------
>> ### Progress
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>> 
>> 
>> 
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>
> src/hotspot/os/linux/os_linux.cpp line 349:
> 
>> 347: 
>> 348:   phys_mem = Linux::physical_memory();
>> 349:   log_trace(os)("total system memory: " "%zu", phys_mem);
> 
> Suggestion:
> 
>   log_trace(os)("total system memory: %zu", phys_mem);

The same in other places.

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PR Review Comment: https://git.openjdk.org/jdk/pull/25450#discussion_r2111426324