joy/android_packages_modules_Connectivity
Watch
1
Fork
You've already forked android_packages_modules_Connectivity
 0
Code Issues Pull requests Projects Releases Wiki Activity

Merge "BpfRingbuf.h: add using-s" into main

Browse source
This commit is contained in:
Maciej Żenczykowski 2025-09-12 07:09:52 -07:00 • committed by Android (Google) Code Review
commit c3f84096de
1 changed files with 20 additions and 20 deletions
Download patch file Download diff file Expand all files Collapse all files

40
bpf/headers/include/bpf/BpfRingbuf.h
View file

@ -31,6 +31,10 @@
namespace android {
namespace bpf {
using android::base::ErrnoError;
using android::base::Result;
using android::base::unique_fd;
// BpfRingbufBase contains the non-templated functionality of BPF ring buffers.
class BpfRingbufBase {
public:
@ -62,10 +66,10 @@ class BpfRingbufBase {
BpfRingbufBase(const BpfRingbufBase&) = delete;
// Initialize the base ringbuffer components. Must be called exactly once.
base::Result<void> Init(const char* path);
Result<void> Init(const char* path);
// Consumes all messages from the ring buffer, passing them to the callback.
base::Result<int> ConsumeAll(
Result<int> ConsumeAll(
const std::function<void(const void*)>& callback);
// Replicates c-style void* "byte-wise" pointer addition.
@ -86,7 +90,7 @@ class BpfRingbufBase {
size_t mConsumerSize;
size_t mProducerSize;
unsigned long mPosMask;
android::base::unique_fd mRingFd;
unique_fd mRingFd;
void* mDataPos = nullptr;
// The kernel uses an "unsigned long" type for both consumer and producer position.
@ -138,7 +142,7 @@ class BpfRingbuf : public BpfRingbufBase {
// Creates a ringbuffer wrapper from a pinned path. There are no guarantees
// that the ringbuf outputs messaged of type `Value`, only that they are the
// same size. Size is only checked in ConsumeAll.
static base::Result<std::unique_ptr<BpfRingbuf<Value>>> Create(
static Result<std::unique_ptr<BpfRingbuf<Value>>> Create(
const char* path);
int epoll_ctl_add(int epfd, struct epoll_event *event) {
@ -156,7 +160,7 @@ class BpfRingbuf : public BpfRingbufBase {
// Consumes all messages from the ring buffer, passing them to the callback.
// Returns the number of messages consumed or a non-ok result on error. If the
// ring buffer has no pending messages an OK result with count 0 is returned.
base::Result<int> ConsumeAll(const MessageCallback& callback);
Result<int> ConsumeAll(const MessageCallback& callback);
protected:
// Empty ctor for use by Create.
@ -164,29 +168,27 @@ class BpfRingbuf : public BpfRingbufBase {
};
inline base::Result<void> BpfRingbufBase::Init(const char* path) {
inline Result<void> BpfRingbufBase::Init(const char* path) {
mRingFd.reset(mapRetrieveExclusiveRW(path));
if (!mRingFd.ok()) {
return android::base::ErrnoError()
<< "failed to retrieve ringbuffer at " << path;
return ErrnoError() << "failed to retrieve ringbuffer at " << path;
}
int map_type = android::bpf::bpfGetFdMapType(mRingFd);
if (map_type != BPF_MAP_TYPE_RINGBUF) {
errno = EINVAL;
return android::base::ErrnoError()
return ErrnoError()
<< "bpf map has wrong type: want BPF_MAP_TYPE_RINGBUF ("
<< BPF_MAP_TYPE_RINGBUF << ") got " << map_type;
}
int max_entries = android::bpf::bpfGetFdMaxEntries(mRingFd);
if (max_entries < 0) {
return android::base::ErrnoError()
<< "failed to read max_entries from ringbuf";
return ErrnoError() << "failed to read max_entries from ringbuf";
}
if (max_entries == 0) {
errno = EINVAL;
return android::base::ErrnoError() << "max_entries must be non-zero";
return ErrnoError() << "max_entries must be non-zero";
}
mPosMask = max_entries - 1;
@ -197,8 +199,7 @@ inline base::Result<void> BpfRingbufBase::Init(const char* path) {
void* ptr = mmap(NULL, mConsumerSize, PROT_READ | PROT_WRITE, MAP_SHARED,
mRingFd, 0);
if (ptr == MAP_FAILED) {
return android::base::ErrnoError()
<< "failed to mmap ringbuf consumer pages";
return ErrnoError() << "failed to mmap ringbuf consumer pages";
}
mConsumerPos = reinterpret_cast<decltype(mConsumerPos)>(ptr);
}
@ -207,8 +208,7 @@ inline base::Result<void> BpfRingbufBase::Init(const char* path) {
void* ptr = mmap(NULL, mProducerSize, PROT_READ, MAP_SHARED, mRingFd,
mConsumerSize);
if (ptr == MAP_FAILED) {
return android::base::ErrnoError()
<< "failed to mmap ringbuf producer page";
return ErrnoError() << "failed to mmap ringbuf producer page";
}
mProducerPos = reinterpret_cast<decltype(mProducerPos)>(ptr);
}
@ -233,7 +233,7 @@ inline bool BpfRingbufBase::wait(int timeout_ms) {
return !isEmpty();
}
inline base::Result<int> BpfRingbufBase::ConsumeAll(
inline Result<int> BpfRingbufBase::ConsumeAll(
const std::function<void(const void*)>& callback) {
int64_t count = 0;
uint32_t prod_pos = mProducerPos->load(std::memory_order_acquire);
@ -260,7 +260,7 @@ inline base::Result<int> BpfRingbufBase::ConsumeAll(
if (length != mValueSize) {
mConsumerPos->store(cons_pos, std::memory_order_release);
errno = EMSGSIZE;
return android::base::ErrnoError()
return ErrnoError()
<< "BPF ring buffer message has unexpected size (want "
<< mValueSize << " bytes, got " << length << " bytes)";
}
@ -275,7 +275,7 @@ inline base::Result<int> BpfRingbufBase::ConsumeAll(
}
template <typename Value>
inline base::Result<std::unique_ptr<BpfRingbuf<Value>>>
inline Result<std::unique_ptr<BpfRingbuf<Value>>>
BpfRingbuf<Value>::Create(const char* path) {
auto rb = std::unique_ptr<BpfRingbuf>(new BpfRingbuf);
if (auto status = rb->Init(path); !status.ok()) return status.error();
@ -283,7 +283,7 @@ BpfRingbuf<Value>::Create(const char* path) {
}
template <typename Value>
inline base::Result<int> BpfRingbuf<Value>::ConsumeAll(
inline Result<int> BpfRingbuf<Value>::ConsumeAll(
const MessageCallback& callback) {
return BpfRingbufBase::ConsumeAll([&](const void* value) {
callback(*reinterpret_cast<const Value*>(value));