composer/cpuhint.cpp

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#include <cutils/properties.h>
#include <dlfcn.h>
#include <utils/debug.h>

#include "cpuhint.h"
#include "hwc_debugger.h"

#define __CLASS__ "CPUHint"

namespace sdm {

DisplayError CPUHint::Init(HWCDebugHandler *debug_handler) {
  char path[PROPERTY_VALUE_MAX];
  if (debug_handler->GetProperty("ro.vendor.extension_library", path) != kErrorNone) {
    DLOGI("Vendor Extension Library not enabled");
    return kErrorNotSupported;
  }

  if (vendor_ext_lib_.Open(path)) {
    if (!vendor_ext_lib_.Sym("perf_event_offload", reinterpret_cast<void **> \
        (&fn_perf_event_offload_))) {
      DLOGW("Failed to load symbols for Vendor Extension Library");
      return kErrorNotSupported;
    }
    DLOGI("Successfully Loaded Vendor Extension Library symbols");
    enabled_ = (fn_perf_event_offload_ != NULL);
  } else {
    DLOGW("Failed to open %s : %s", path, vendor_ext_lib_.Error());
  }

  return enabled_ ? kErrorNone : kErrorNotSupported;
}

void CPUHint::ReqHintsOffload(int hint, int duration) {
  if(enabled_ && hint > 0) {
    int args[] = {0, duration};
    int handle = fn_perf_event_offload_(hint, NULL, 2, args);
    if (handle < 0) {
      DLOGW("Failed to send hint 0x%x. handle = %d", hint, handle);
    }
  }
}
}  // namespace sdm