Files
kernels/runtime/src/vx_spawn.c

112 lines
2.6 KiB
C

#include <vx_spawn.h>
#include <vx_intrinsics.h>
#include <inttypes.h>
#ifdef __cplusplus
extern "C" {
#endif
#define NUM_CORES_MAX 16
#define MIN(a, b) ((a) < (b) ? (a) : (b))
typedef struct {
pfn_callback callback;
void * args;
int offset;
int N;
int R;
} wspawn_args_t;
wspawn_args_t* g_wspawn_args[NUM_CORES_MAX];
void spawn_tasks_callback() {
vx_tmc(vx_num_threads());
int core_id = vx_core_id();
int wid = vx_warp_id();
int tid = vx_thread_id();
int NT = vx_num_threads();
wspawn_args_t* p_wspawn_args = g_wspawn_args[core_id];
int wK = (p_wspawn_args->N * wid) + MIN(p_wspawn_args->R, wid);
int tK = p_wspawn_args->N + (wid < p_wspawn_args->R);
int offset = p_wspawn_args->offset + (wK * NT) + (tid * tK);
for (int task_id = offset, N = task_id + tK; task_id < N; ++task_id) {
(p_wspawn_args->callback)(task_id, p_wspawn_args->args);
}
vx_tmc(0 == wid);
}
void spawn_remaining_tasks_callback(int nthreads) {
vx_tmc(nthreads);
int core_id = vx_core_id();
int tid = vx_thread_gid();
wspawn_args_t* p_wspawn_args = g_wspawn_args[core_id];
int task_id = p_wspawn_args->offset + tid;
(p_wspawn_args->callback)(task_id, p_wspawn_args->args);
vx_tmc(1);
}
void vx_spawn_tasks(int num_tasks, pfn_callback callback , void * args) {
// device specs
int NC = vx_num_cores();
int NW = vx_num_warps();
int NT = vx_num_threads();
// current core id
int core_id = vx_core_id();
if (core_id >= NUM_CORES_MAX)
return;
// calculate necessary active cores
int WT = NW * NT;
int nC = (num_tasks > WT) ? (num_tasks / WT) : 1;
int nc = MIN(nC, NC);
if (core_id >= nc)
return; // terminate unused cores
// number of tasks per core
int tasks_per_core = num_tasks / nc;
int tasks_per_core0 = tasks_per_core;
if (core_id == (NC-1)) {
int QC_r = num_tasks - (nc * tasks_per_core0);
tasks_per_core0 += QC_r; // last core executes remaining tasks
}
// number of tasks per warp
int nW = tasks_per_core0 / NT; // total warps per core
int rT = tasks_per_core0 - (nW * NT); // remaining threads
int fW = (nW >= NW) ? (nW / NW) : 0; // full warps iterations
int rW = (fW != 0) ? (nW - fW * NW) : 0; // remaining warps
if (0 == fW)
fW = 1;
//--
wspawn_args_t wspawn_args = { callback, args, core_id * tasks_per_core, fW, rW };
g_wspawn_args[core_id] = &wspawn_args;
//--
if (nW > 1) {
int nw = MIN(nW, NW);
vx_wspawn(nw, (unsigned)&spawn_tasks_callback);
spawn_tasks_callback();
}
//--
if (rT != 0) {
wspawn_args.offset = tasks_per_core0 - rT;
spawn_remaining_tasks_callback(rT);
}
}
#ifdef __cplusplus
}
#endif