IoUringProvidedBufferRing: make huge pages configurable

Summary: As per title, and make it false by default as there's a known issue with kernel v6.9 + huge pages + provided buffers.

Reviewed By: yfeldblum

Differential Revision: D72349394

fbshipit-source-id: c4282b964f4dac1227076cf1e1a2562fbb887fde

Author: spikeh

folly/io/async/IoUringProvidedBufferRing.cpp

@@ -85,11 +85,12 @@ IoUringProvidedBufferRing::IoUringProvidedBufferRing(
     uint16_t gid,
     int count,
     int bufferShift,
-    int ringSizeShift)
+    int ringSizeShift,
+    bool useHugePages)
     : IoUringBufferProviderBase(
           gid, ProvidedBuffersBuffer::calcBufferSize(bufferShift)),
       ioRingPtr_(ioRingPtr),
-      buffer_(count, bufferShift, ringSizeShift, true) {
+      buffer_(count, bufferShift, ringSizeShift, useHugePages) {
   if (count > std::numeric_limits<uint16_t>::max()) {
     throw std::runtime_error("too many buffers");
   }

folly/io/async/IoUringProvidedBufferRing.h

@@ -38,7 +38,8 @@ class IoUringProvidedBufferRing : public IoUringBufferProviderBase {
       uint16_t gid,
       int count,
       int bufferShift,
-      int ringSizeShift);
+      int ringSizeShift,
+      bool useHugePages = false);
 
   void enobuf() noexcept override;
   void unusedBuf(uint16_t i) noexcept override;

folly/io/async/test/IoUringProvidedBufferRingTest.cpp

@@ -39,7 +39,17 @@ TEST_F(IoUringProvidedBufferRingTest, Create) {
   io_uring_queue_init(512, &ring, 0);
   int sizeShift = std::max<int>(get_shift(4096), 5);
   int ringShift = std::max<int>(get_shift(1000), 1);
-  IoUringProvidedBufferRing bufRing{&ring, 1, 1000, sizeShift, ringShift};
+  IoUringProvidedBufferRing bufRing{&ring, 1, 1000, sizeShift, ringShift, true};
+  EXPECT_EQ(bufRing.count(), 1000);
+}
+
+TEST_F(IoUringProvidedBufferRingTest, CreateNoHugepages) {
+  io_uring ring{};
+  io_uring_queue_init(512, &ring, 0);
+  int sizeShift = std::max<int>(get_shift(4096), 5);
+  int ringShift = std::max<int>(get_shift(1000), 1);
+  IoUringProvidedBufferRing bufRing{
+      &ring, 1, 1000, sizeShift, ringShift, false};
   EXPECT_EQ(bufRing.count(), 1000);
 }