diff options
Diffstat (limited to 'arch/tile/lib')
| -rw-r--r-- | arch/tile/lib/cacheflush.c | 28 |
1 files changed, 26 insertions, 2 deletions
diff --git a/arch/tile/lib/cacheflush.c b/arch/tile/lib/cacheflush.c index 6af2b97a6886..db4fb89e12d8 100644 --- a/arch/tile/lib/cacheflush.c +++ b/arch/tile/lib/cacheflush.c @@ -39,7 +39,21 @@ void finv_buffer_remote(void *buffer, size_t size, int hfh) { char *p, *base; size_t step_size, load_count; + + /* + * On TILEPro the striping granularity is a fixed 8KB; on + * TILE-Gx it is configurable, and we rely on the fact that + * the hypervisor always configures maximum striping, so that + * bits 9 and 10 of the PA are part of the stripe function, so + * every 512 bytes we hit a striping boundary. + * + */ +#ifdef __tilegx__ + const unsigned long STRIPE_WIDTH = 512; +#else const unsigned long STRIPE_WIDTH = 8192; +#endif + #ifdef __tilegx__ /* * On TILE-Gx, we must disable the dstream prefetcher before doing @@ -74,7 +88,7 @@ void finv_buffer_remote(void *buffer, size_t size, int hfh) * memory, that one load would be sufficient, but since we may * be, we also need to back up to the last load issued to * another memory controller, which would be the point where - * we crossed an 8KB boundary (the granularity of striping + * we crossed a "striping" boundary (the granularity of striping * across memory controllers). Keep backing up and doing this * until we are before the beginning of the buffer, or have * hit all the controllers. @@ -88,12 +102,22 @@ void finv_buffer_remote(void *buffer, size_t size, int hfh) * every cache line on a full memory stripe on each * controller" that we simply do that, to simplify the logic. * - * FIXME: See bug 9535 for some issues with this code. + * On TILE-Gx the hash-for-home function is much more complex, + * with the upshot being we can't readily guarantee we have + * hit both entries in the 128-entry AMT that were hit by any + * load in the entire range, so we just re-load them all. + * With larger buffers, we may want to consider using a hypervisor + * trap to issue loads directly to each hash-for-home tile for + * each controller (doing it from Linux would trash the TLB). */ if (hfh) { step_size = L2_CACHE_BYTES; +#ifdef __tilegx__ + load_count = (size + L2_CACHE_BYTES - 1) / L2_CACHE_BYTES; +#else load_count = (STRIPE_WIDTH / L2_CACHE_BYTES) * (1 << CHIP_LOG_NUM_MSHIMS()); +#endif } else { step_size = STRIPE_WIDTH; load_count = (1 << CHIP_LOG_NUM_MSHIMS()); |