[Mesa-dev] [PATCH] src: replace RTLD_NOW with RTLD_LAZY

[⚛]

On Sat, Aug 6, 2016 at 3:37 AM, Jan Vesely <jan.vesely at rutgers.edu> wrote:
> On Sat, 2016-08-06 at 02:42 +0200, Jan Ziak wrote:
>> Mesa source code prior to this patch uses both RTLD_NOW and
>> RTLD_LAZY.
>> This patch removes all RTLD_NOW in favor of RTLD_LAZY.
>>
>> In comparison to early binding, lazy binding reduces CPU instruction
>> count
>> of small GL apps (e.g: glxinfo) by 6 million instructions.
>> Larger apps won't notice the difference.
>
> this is IMO micro-optimization in the wrong place. RTLD_NOW also
> guarantees that symbols were successfully resolved. Changing it to lazy
> may hide bugs by deferring failure to future point in the execution.

Question 1: Are you suggesting to replace current RTLD_LAZY in all
locations with RTLD_NOW?

Question 2: Exists there a reason for _not_ linking radeonsi_dri.so,
swrastg_dri.so, etc, directly to Mesa's libGL.so? The Gallium
*_dri.so libraries are the same inode on the filesystem.

Question 3: Isn't the current status quo (i.e: not linking
radeonsi_dri.so directly to libGL.so) also a micro-optimization that
can hide certain bugs?

Question 4: Is it planned for *_dri.so belonging to Gallium/DRI _not_
to be mapped to the same inode on the filesystem in the future? If
there is no such plan, what was the original point of having multiple
_dri.so files mapped to the same inode?

Thanks.