Switch Linux-aio implementation away from libaio

Drop libaio calls, start using internal implementation. Note that the internal implementation returns errors in the system call convention (-1 + errno) rather than the kernel convention (-error).
liangxiaoping · Jan 2, 2018 · 499cbf8 · 499cbf8
1 parent 27158ce
commit 499cbf8
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Showing 6 changed files with 52 additions and 48 deletions.
diff --git a/apps/iotune/iotune.cc b/apps/iotune/iotune.cc
@@ -26,7 +26,6 @@
 #include <memory>
 #include <vector>
 #include <cmath>
-#include <libaio.h>
 #include <wordexp.h>
 #include <boost/thread/barrier.hpp>
 #include <boost/filesystem.hpp>
@@ -38,13 +37,15 @@
 #include <queue>
 #include <fstream>
 #include <future>
+#include "core/linux-aio.hh"
 #include "core/sstring.hh"
 #include "core/posix.hh"
 #include "core/resource.hh"
 #include "core/aligned_buffer.hh"
 #include "util/defer.hh"
 
 using namespace seastar;
+using namespace seastar::internal;
 using namespace std::chrono_literals;
 
 namespace seastar {
@@ -478,8 +479,8 @@ class reader {
     {}
 
     iocb* issue() {
-        io_prep_pread(&_iocb, _file.get(), _buf.get(), iotune_manager::rbuffer_size, _pos_distribution(random_generator) * iotune_manager::rbuffer_size);
-        _iocb.data = this;
+        _iocb = make_read_iocb(_file.get(), _pos_distribution(random_generator) * iotune_manager::rbuffer_size, _buf.get(), iotune_manager::rbuffer_size);
+        set_user_data(_iocb, this);
         _tstamp = std::chrono::steady_clock::now();
         return &_iocb;
     }
@@ -517,10 +518,10 @@ void sanity_check_ev(const io_event& ev, size_t size) {
 }
 
 run_stats iotune_manager::issue_reads(size_t cpu_id, unsigned concurrency) {
-    io_context_t io_context = {0};
-    auto r = ::io_setup(concurrency, &io_context);
+    ::aio_context_t io_context = {0};
+    auto r = io_setup(concurrency, &io_context);
     assert(r >= 0);
-    auto destroyer = defer([&io_context] { ::io_destroy(io_context); });
+    auto destroyer = defer([&io_context] { io_destroy(io_context); });
 
     unsigned finished = 0;
     std::vector<io_event> ev;
@@ -541,13 +542,13 @@ run_stats iotune_manager::issue_reads(size_t cpu_id, unsigned concurrency) {
         iocb_vecptr.push_back(r.issue());
     }
 
-    r = ::io_submit(io_context, iocb_vecptr.size(), iocb_vecptr.data());
-    throw_kernel_error(r);
+    r = io_submit(io_context, iocb_vecptr.size(), iocb_vecptr.data());
+    throw_system_error_on(r == -1, "io_submit");
 
     struct timespec timeout = {0, 0};
     while (finished != concurrency) {
-        int n = ::io_getevents(io_context, 1, ev.size(), ev.data(), &timeout);
-        throw_kernel_error(n);
+        int n = io_getevents(io_context, 1, ev.size(), ev.data(), &timeout);
+        throw_system_error_on(n == -1, "io_getevents");
         unsigned new_req = 0;
         for (auto i = 0ul; i < size_t(n); ++i) {
             sanity_check_ev(ev[i], iotune_manager::rbuffer_size);
@@ -560,7 +561,7 @@ run_stats iotune_manager::issue_reads(size_t cpu_id, unsigned concurrency) {
             }
         }
         r = ::io_submit(io_context, new_req, iocb_vecptr.data());
-        throw_kernel_error(r);
+        throw_system_error_on(r == -1, "io_submit");
     }
     struct run_stats result;
     for (auto&& r: fds) {
@@ -579,11 +580,11 @@ void test_file::generate(iotune_manager& iotune_manager, std::chrono::seconds ti
     auto start_time = iotune_manager::clock::now();
     auto latest_tstamp = start_time;
 
-    io_context_t io_context = {0};
+    aio_context_t io_context = {0};
     auto max_aio = 128;
-    auto r = ::io_setup(max_aio, &io_context);
+    auto r = io_setup(max_aio, &io_context);
     assert(r >= 0);
-    auto destroyer = defer([&io_context] { ::io_destroy(io_context); });
+    auto destroyer = defer([&io_context] { io_destroy(io_context); });
 
     auto buf = allocate_aligned_buffer<char>(iotune_manager::wbuffer_size, 4096);
     memset(buf.get(), 0, iotune_manager::wbuffer_size);
@@ -608,19 +609,19 @@ void test_file::generate(iotune_manager& iotune_manager, std::chrono::seconds ti
         while (i < max_aio - aio_outstanding && pos < iotune_manager.file_size) {
             auto now = std::min(iotune_manager.file_size - pos, iotune_manager::wbuffer_size);
             auto& iocb = iocbs[i++];
-            iocb.data = buf.get();
-            io_prep_pwrite(&iocb, file.get(), buf.get(), now, pos);
+            iocb = make_write_iocb(file.get(), pos, buf.get(), now);
+            set_user_data(iocb, buf.get());
             pos += now;
         }
         if (i) {
-            r = ::io_submit(io_context, i, iocb_vecptr.data());
-            throw_kernel_error(r);
+            r = io_submit(io_context, i, iocb_vecptr.data());
+            throw_system_error_on(r == -1, "io_submit");
             aio_outstanding += r;
         }
         if (aio_outstanding) {
             struct timespec timeout = {0, 0};
-            int n = ::io_getevents(io_context, 1, ev.size(), ev.data(), &timeout);
-            throw_kernel_error(n);
+            int n = io_getevents(io_context, 1, ev.size(), ev.data(), &timeout);
+            throw_system_error_on(n == -1, "io_getevents");
             aio_outstanding -= n;
             for (auto i = 0ul; i < size_t(n); ++i) {
                 if (stopped_on_error) {

diff --git a/configure.py b/configure.py
@@ -431,8 +431,7 @@ def maybe_static(flag, libs):
 
 defines = ['FMT_HEADER_ONLY']
 # Include -lgcc_s before -lunwind to work around for https://savannah.nongnu.org/bugs/?48486. See https://github.com/scylladb/scylla/issues/1725.
-libs = ' '.join(['-laio',
-                 maybe_static(args.staticboost,
+libs = ' '.join([maybe_static(args.staticboost,
                               '-lboost_program_options -lboost_system -lboost_filesystem'),
                  '-lstdc++ -lm',
                  maybe_static(args.staticboost, '-lboost_thread'),
@@ -497,7 +496,7 @@ def maybe_static(flag, libs):
     'tests/fair_queue_test': ['tests/fair_queue_test.cc'] + core,
     'apps/seawreck/seawreck': ['apps/seawreck/seawreck.cc', 'http/http_response_parser.rl'] + core + libnet,
     'apps/io_tester/io_tester': ['apps/io_tester/io_tester.cc'] + core,
-    'apps/iotune/iotune': ['apps/iotune/iotune.cc'] + ['core/resource.cc', 'core/fsqual.cc'],
+    'apps/iotune/iotune': ['apps/iotune/iotune.cc'] + ['core/resource.cc', 'core/fsqual.cc', 'core/linux-aio.cc'],
     'tests/blkdiscard_test': ['tests/blkdiscard_test.cc'] + core,
     'tests/sstring_test': ['tests/sstring_test.cc'] + core,
     'tests/unwind_test': ['tests/unwind_test.cc'] + core,

diff --git a/core/fsqual.cc b/core/fsqual.cc
@@ -21,7 +21,7 @@
 
 #include "posix.hh"
 #include "util/defer.hh"
-#include <libaio.h>
+#include "core/linux-aio.hh"
 #include <sys/time.h>
 #include <sys/resource.h>
 #include <fcntl.h>
@@ -33,6 +33,8 @@
 
 namespace seastar {
 
+using namespace seastar::internal;
+
 // Runs func(), and also adds the number of context switches
 // that happened during func() to counter.
 template <typename Counter, typename Func>
@@ -57,9 +59,9 @@ with_ctxsw_counting(Counter& counter, Func&& func) {
 }
 
 bool filesystem_has_good_aio_support(sstring directory, bool verbose) {
-    io_context_t ioctx = {};
+    aio_context_t ioctx = {};
     auto r = io_setup(1, &ioctx);
-    throw_kernel_error(r);
+    throw_system_error_on(r == -1, "io_setup");
     auto cleanup = defer([&] { io_destroy(ioctx); });
     auto fname = directory + "/fsqual.tmp";
     auto fd = file_desc::open(fname, O_CREAT|O_EXCL|O_RDWR|O_DIRECT, 0600);
@@ -71,16 +73,16 @@ bool filesystem_has_good_aio_support(sstring directory, bool verbose) {
     auto buf = aligned_alloc(4096, 4096);
     for (int i = 0; i < nr; ++i) {
         struct iocb cmd;
-        io_prep_pwrite(&cmd, fd.get(), buf, bufsize, bufsize*i);
+        cmd = make_write_iocb(fd.get(), bufsize*i, buf, bufsize);
         struct iocb* cmds[1] = { &cmd };
         with_ctxsw_counting(ctxsw, [&] {
             auto r = io_submit(ioctx, 1, cmds);
-            throw_kernel_error(r);
+            throw_system_error_on(r == -1, "io_submit");
             assert(r == 1);
         });
         struct io_event ioev;
         auto n = io_getevents(ioctx, 1, 1, &ioev, nullptr);
-        throw_kernel_error(n);
+        throw_system_error_on(n == -1, "io_getevents");
         assert(n == 1);
         throw_kernel_error(long(ioev.res));
         assert(long(ioev.res) == bufsize);

diff --git a/core/reactor.cc b/core/reactor.cc
@@ -107,6 +107,8 @@ using namespace std::chrono_literals;
 
 using namespace net;
 
+using namespace internal;
+
 seastar::logger seastar_logger("seastar");
 seastar::logger sched_logger("scheduler");
 
@@ -431,7 +433,7 @@ reactor::reactor(unsigned id)
     _task_queues.push_back(std::make_unique<task_queue>(1, "atexit", 1000));
     _at_destroy_tasks = _task_queues.back().get();
     seastar::thread_impl::init();
-    auto r = ::io_setup(max_aio, &_io_context);
+    auto r = io_setup(max_aio, &_io_context);
     assert(r >= 0);
 #ifdef HAVE_OSV
     _timer_thread.start();
@@ -478,7 +480,7 @@ reactor::~reactor() {
     eraser(_expired_timers);
     eraser(_expired_lowres_timers);
     eraser(_expired_manual_timers);
-    ::io_destroy(_io_context);
+    io_destroy(_io_context);
 }
 
 // Add to an atomic integral non-atomically and returns the previous value
@@ -876,10 +878,10 @@ reactor::submit_io(Func prepare_io) {
         iocb io;
         prepare_io(io);
         if (_aio_eventfd) {
-            io_set_eventfd(&io, _aio_eventfd->get_fd());
+            set_eventfd_notification(io, _aio_eventfd->get_fd());
         }
         auto f = pr->get_future();
-        io.data = pr.get();
+        set_user_data(io, pr.get());
         _pending_aio.push_back(io);
         pr.release();
         if ((_io_queue->queued_requests() > 0) ||
@@ -899,15 +901,15 @@ reactor::flush_pending_aio() {
         for (size_t i = 0; i < nr; ++i) {
             iocbs[i] = &_pending_aio[i];
         }
-        auto r = ::io_submit(_io_context, nr, iocbs);
+        auto r = io_submit(_io_context, nr, iocbs);
         size_t nr_consumed;
-        if (r < 0) {
-            auto ec = -r;
+        if (r == -1) {
+            auto ec = errno;
             switch (ec) {
                 case EAGAIN:
                     return did_work;
                 case EBADF: {
-                    auto pr = reinterpret_cast<promise<io_event>*>(iocbs[0]->data);
+                    auto pr = reinterpret_cast<promise<io_event>*>(get_user_data(*iocbs[0]));
                     try {
                         throw_kernel_error(r);
                     } catch (...) {
@@ -921,7 +923,7 @@ reactor::flush_pending_aio() {
                     break;
                 }
                 default:
-                    throw_kernel_error(r);
+                    throw_system_error_on(true, "io_submit");
                     abort();
             }
         } else {
@@ -965,7 +967,7 @@ bool reactor::process_io()
 {
     io_event ev[max_aio];
     struct timespec timeout = {0, 0};
-    auto n = ::io_getevents(_io_context, 1, max_aio, ev, &timeout);
+    auto n = io_getevents(_io_context, 1, max_aio, ev, &timeout);
     assert(n >= 0);
     for (size_t i = 0; i < size_t(n); ++i) {
         auto pr = reinterpret_cast<promise<io_event>*>(ev[i].data);
@@ -1147,7 +1149,7 @@ posix_file_impl::query_dma_alignment() {
 future<size_t>
 posix_file_impl::write_dma(uint64_t pos, const void* buffer, size_t len, const io_priority_class& io_priority_class) {
     return engine().submit_io_write(io_priority_class, len, [fd = _fd, pos, buffer, len] (iocb& io) {
-        io_prep_pwrite(&io, fd, const_cast<void*>(buffer), len, pos);
+        io = make_write_iocb(fd, pos, const_cast<void*>(buffer), len);
     }).then([] (io_event ev) {
         throw_kernel_error(long(ev.res));
         return make_ready_future<size_t>(size_t(ev.res));
@@ -1161,7 +1163,7 @@ posix_file_impl::write_dma(uint64_t pos, std::vector<iovec> iov, const io_priori
     auto size = iov_ptr->size();
     auto data = iov_ptr->data();
     return engine().submit_io_write(io_priority_class, len, [fd = _fd, pos, data, size] (iocb& io) {
-        io_prep_pwritev(&io, fd, data, size, pos);
+        io = make_writev_iocb(fd, pos, data, size);
     }).then([iov_ptr = std::move(iov_ptr)] (io_event ev) {
         throw_kernel_error(long(ev.res));
         return make_ready_future<size_t>(size_t(ev.res));
@@ -1171,7 +1173,7 @@ posix_file_impl::write_dma(uint64_t pos, std::vector<iovec> iov, const io_priori
 future<size_t>
 posix_file_impl::read_dma(uint64_t pos, void* buffer, size_t len, const io_priority_class& io_priority_class) {
     return engine().submit_io_read(io_priority_class, len, [fd = _fd, pos, buffer, len] (iocb& io) {
-        io_prep_pread(&io, fd, buffer, len, pos);
+        io = make_read_iocb(fd, pos, buffer, len);
     }).then([] (io_event ev) {
         throw_kernel_error(long(ev.res));
         return make_ready_future<size_t>(size_t(ev.res));
@@ -1185,7 +1187,7 @@ posix_file_impl::read_dma(uint64_t pos, std::vector<iovec> iov, const io_priorit
     auto size = iov_ptr->size();
     auto data = iov_ptr->data();
     return engine().submit_io_read(io_priority_class, len, [fd = _fd, pos, data, size] (iocb& io) {
-        io_prep_preadv(&io, fd, data, size, pos);
+        io = make_read_iocb(fd, pos, data, size);
     }).then([iov_ptr = std::move(iov_ptr)] (io_event ev) {
         throw_kernel_error(long(ev.res));
         return make_ready_future<size_t>(size_t(ev.res));

diff --git a/core/reactor.hh b/core/reactor.hh
@@ -29,7 +29,6 @@
 #include "circular_buffer_fixed_capacity.hh"
 #include <memory>
 #include <type_traits>
-#include <libaio.h>
 #include <sys/epoll.h>
 #include <sys/types.h>
 #include <sys/socket.h>
@@ -55,6 +54,7 @@
 #include <boost/thread/barrier.hpp>
 #include <boost/container/static_vector.hpp>
 #include <set>
+#include "linux-aio.hh"
 #include "util/eclipse.hh"
 #include "future.hh"
 #include "posix.hh"
@@ -725,7 +725,7 @@ private:
     timer_set<timer<lowres_clock>, &timer<lowres_clock>::_link>::timer_list_t _expired_lowres_timers;
     timer_set<timer<manual_clock>, &timer<manual_clock>::_link> _manual_timers;
     timer_set<timer<manual_clock>, &timer<manual_clock>::_link>::timer_list_t _expired_manual_timers;
-    io_context_t _io_context;
+    ::aio_context_t _io_context;
     std::vector<struct ::iocb> _pending_aio;
     semaphore _io_context_available;
     io_stats _io_stats;

diff --git a/install-dependencies.sh b/install-dependencies.sh
@@ -28,7 +28,7 @@ if [ "$ID" = "ubuntu" ] || [ "$ID" = "debian" ]; then
         add-apt-repository -y ppa:ubuntu-toolchain-r/test
         apt-get -y update
     fi
-    apt-get install -y libaio-dev ninja-build ragel libhwloc-dev libnuma-dev libpciaccess-dev libcrypto++-dev libboost-all-dev libxml2-dev xfslibs-dev libgnutls28-dev liblz4-dev libsctp-dev gcc make libprotobuf-dev protobuf-compiler python3 libunwind8-dev systemtap-sdt-dev libtool cmake libyaml-cpp-dev
+    apt-get install -y ninja-build ragel libhwloc-dev libnuma-dev libpciaccess-dev libcrypto++-dev libboost-all-dev libxml2-dev xfslibs-dev libgnutls28-dev liblz4-dev libsctp-dev gcc make libprotobuf-dev protobuf-compiler python3 libunwind8-dev systemtap-sdt-dev libtool cmake libyaml-cpp-dev
     if [ "$ID" = "ubuntu" ]; then
         apt-get install -y g++-5
         echo "g++-5 is installed for Seastar. To build Seastar with g++-5, specify '--compiler=g++-5' on configure.py"
@@ -51,7 +51,7 @@ enabled=1
 enabled_metadata=1
 EOF
     fi
-    yum install -y libaio-devel hwloc-devel numactl-devel libpciaccess-devel cryptopp-devel libxml2-devel xfsprogs-devel gnutls-devel lksctp-tools-devel lz4-devel gcc make protobuf-devel protobuf-compiler libunwind-devel systemtap-sdt-devel libtool cmake yaml-cpp-devel
+    yum install -y hwloc-devel numactl-devel libpciaccess-devel cryptopp-devel libxml2-devel xfsprogs-devel gnutls-devel lksctp-tools-devel lz4-devel gcc make protobuf-devel protobuf-compiler libunwind-devel systemtap-sdt-devel libtool cmake yaml-cpp-devel
     if [ "$ID" = "fedora" ]; then
         dnf install -y gcc-c++ ninja-build ragel boost-devel libubsan libasan
     else # centos
@@ -60,7 +60,7 @@ EOF
         echo "Before running ninja-build, execute following command: . /etc/profile.d/scylla.sh"
     fi
 elif [ "$ID" = "arch" -o "$ID_LIKE" = "arch" ]; then
-    pacman -Sy --needed gcc ninja ragel boost boost-libs libaio hwloc numactl libpciaccess crypto++ libxml2 xfsprogs gnutls lksctp-tools lz4 make protobuf libunwind systemtap libtool cmake yaml-cpp
+    pacman -Sy --needed gcc ninja ragel boost boost-libs hwloc numactl libpciaccess crypto++ libxml2 xfsprogs gnutls lksctp-tools lz4 make protobuf libunwind systemtap libtool cmake yaml-cpp
 else
     echo "Your system ($ID) is not supported by this script. Please install dependencies manually."
     exit 1