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/**
* @file
*
* Module to support operations on bitmap of cores. Coremask can be used to
* select a specific core, a group of cores, or all available cores, for
* initialization and differentiation of roles within a single shared binary
* executable image.
*
* <hr>$Revision: 70030 $<hr>
*
*/
#include "cvmx-config.h"
#include "cvmx.h"
#include "cvmx-spinlock.h"
#include "cvmx-coremask.h"
#define CVMX_COREMASK_MAX_SYNCS 20 /* maximum number of coremasks for barrier sync */
/**
* This structure defines the private state maintained by coremask module.
*
*/
CVMX_SHARED static struct {
cvmx_spinlock_t lock; /**< mutex spinlock */
struct {
unsigned int coremask; /**< coremask specified for barrier */
unsigned int checkin; /**< bitmask of cores checking in */
volatile unsigned int exit; /**< variable to poll for exit condition */
} s[CVMX_COREMASK_MAX_SYNCS];
} state = {
{ CVMX_SPINLOCK_UNLOCKED_VAL },
{ { 0, 0, 0 } },
};
/**
* Wait (stall) until all cores in the given coremask has reached this point
* in the program execution before proceeding.
*
* @param coremask the group of cores performing the barrier sync
*
*/
void cvmx_coremask_barrier_sync(unsigned int coremask)
{
int i;
unsigned int target;
assert(coremask != 0);
cvmx_spinlock_lock(&state.lock);
for (i = 0; i < CVMX_COREMASK_MAX_SYNCS; i++) {
if (state.s[i].coremask == 0) {
/* end of existing coremask list, create new entry, fall-thru */
state.s[i].coremask = coremask;
}
if (state.s[i].coremask == coremask) {
target = state.s[i].exit + 1; /* wrap-around at 32b */
state.s[i].checkin |= cvmx_coremask_core(cvmx_get_core_num());
if (state.s[i].checkin == coremask) {
state.s[i].checkin = 0;
state.s[i].exit = target; /* signal exit condition */
}
cvmx_spinlock_unlock(&state.lock);
while (state.s[i].exit != target)
;
return;
}
}
/* error condition - coremask array overflowed */
cvmx_spinlock_unlock(&state.lock);
assert(0);
}