On Thu, Oct 19, 2017 at 3:25 PM, Timothy Arceri <tarc...@itsqueeze.com> wrote:
> Maybe add to docs? > I'm not sure how I feel about that. I'm scared to death of options like this becoming something some random user on the internet decides they should use because it keeps the pre-populated shader cache they downloaded work. To be honest, I'd probably feel more comfortable about it being hidden behind an "if (0) {" so that you can't get to it without hacking up the driver. I think I'm ok with it as-is though. --Jason > On 19/10/17 16:32, Jordan Justen wrote: > >> The MESA_GLSL_CACHE_TIMESTAMP environment variable can be set to >> override the driver timestamp. Usually the driver will specify a hash >> of their driver build so the cache items become invalid with each >> driver build. >> >> We don't guarantee a stable serialized shader cache format, so >> changing the timestamp for each build is required for safety. >> >> Nevertheless, during debug, making small changes to the driver may be >> known to be safe. The driver developer can use this variable to keep >> the timestamp consistent. When debugging issues on an application for >> which the shader cache greatly lowers the startup time, this can save >> the developer significant time. >> >> Signed-off-by: Jordan Justen <jordan.l.jus...@intel.com> >> --- >> src/util/disk_cache.c | 12 ++++++++++++ >> 1 file changed, 12 insertions(+) >> >> diff --git a/src/util/disk_cache.c b/src/util/disk_cache.c >> index fde6e2e097..54f48a8ba5 100644 >> --- a/src/util/disk_cache.c >> +++ b/src/util/disk_cache.c >> @@ -208,6 +208,18 @@ disk_cache_create(const char *gpu_name, const char >> *timestamp, >> if (env_var_as_boolean("MESA_GLSL_CACHE_DISABLE", false)) >> goto fail; >> +#ifdef DEBUG >> + /* For debug builds, MESA_GLSL_CACHE_TIMESTAMP can be set to override >> the >> + * driver specified timestamp. This will allow small changes to be >> made to >> + * the driver without invalidating the cache. Given that this is >> normally >> + * unsafe, it is only allowed for debug builds. >> + */ >> + const char *timestamp_override = getenv("MESA_GLSL_CACHE_TIMESTAMP"); >> + if (timestamp_override) { >> + timestamp = timestamp_override; >> + } >> +#endif >> + >> /* Determine path for cache based on the first defined name as >> follows: >> * >> * $MESA_GLSL_CACHE_DIR >> >> _______________________________________________ > mesa-dev mailing list > mesa-dev@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/mesa-dev >
_______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev