GOSTSec/sgminer
1
0
Fork 0
mirror of https://github.com/GOSTSec/sgminer synced 2025-03-10 04:31:03 +00:00
Code Issues Releases Wiki Activity

Find the nearest power of 2 maximum alloc size for the scrypt buffer that can successfully be allocated and is large enough to accomodate the thread concurrency chosen, thus mapping it to an intensity.

Browse Source
This commit is contained in:
Con Kolivas 2012-07-25 22:02:14 +10:00
parent bff58c3bed
commit ea10b08dce
1 changed files with 21 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
ocl.c
View File

@ -472,17 +472,35 @@ _clState *initCl(unsigned int gpu, char *name, size_t nameSize)
#ifdef USE_SCRYPT
if (opt_scrypt) {
cl_ulong ma = gpus[gpu].max_alloc, mt;
int pow2 = 0;
if (!gpus[gpu].lookup_gap) {
applog(LOG_DEBUG, "GPU %d: selecting lookup gap of 2", gpu);
gpus[gpu].lookup_gap = 2;
}
if (!gpus[gpu].thread_concurrency) {
gpus[gpu].thread_concurrency = gpus[gpu].max_alloc / 32768 / gpus[gpu].lookup_gap;
gpus[gpu].thread_concurrency = ma / 32768 / gpus[gpu].lookup_gap;
if (gpus[gpu].shaders && gpus[gpu].thread_concurrency > gpus[gpu].shaders)
gpus[gpu].thread_concurrency -= gpus[gpu].thread_concurrency % gpus[gpu].shaders;
applog(LOG_DEBUG, "GPU %d: selecting thread concurrency of %u",gpu, gpus[gpu].thread_concurrency);
}
/* If we have memory to spare, try to find a power of 2 value
* >= required amount to map nicely to an intensity */
mt = gpus[gpu].thread_concurrency * 32768 * gpus[gpu].lookup_gap;
if (ma > mt) {
while (ma >>= 1)
pow2++;
ma = 1;
while (--pow2 && ma < mt)
ma <<= 1;
if (ma >= mt) {
gpus[gpu].max_alloc = ma;
applog(LOG_DEBUG, "Max alloc decreased to %lu", gpus[gpu].max_alloc);
}
}
}
#endif
@ -776,8 +794,8 @@ built:
size_t ipt = (1024 / gpus[gpu].lookup_gap + (1024 % gpus[gpu].lookup_gap > 0));
size_t bufsize = 128 * ipt * gpus[gpu].thread_concurrency;
/* Always allocate the largest possible buffer allowed, even if we're not initially requiring it
* based on thread_concurrency, giving us some headroom for intensity levels. */
/* Use the max alloc value which has been rounded to a power of
* 2 greater >= required amount earlier */
if (bufsize > gpus[gpu].max_alloc) {
applog(LOG_WARNING, "Maximum buffer memory device %d supports says %u, your scrypt settings come to %u",
gpu, gpus[gpu].max_alloc, bufsize);