Author: asomers Date: Mon Apr 16 18:12:15 2018 New Revision: 332631 URL: https://svnweb.freebsd.org/changeset/base/332631
Log: lio_listio: return EAGAIN instead of EIO when out of resources This behavior is already documented by the man page, and suggested by POSIX. Reviewed by: jhb MFC after: 3 weeks Differential Revision: https://reviews.freebsd.org/D15099 Modified: head/sys/kern/vfs_aio.c head/tests/sys/aio/Makefile head/tests/sys/aio/lio_test.c Modified: head/sys/kern/vfs_aio.c ============================================================================== --- head/sys/kern/vfs_aio.c Mon Apr 16 18:07:51 2018 (r332630) +++ head/sys/kern/vfs_aio.c Mon Apr 16 18:12:15 2018 (r332631) @@ -2131,7 +2131,7 @@ kern_lio_listio(struct thread *td, int mode, struct ai struct aioliojob *lj; struct kevent kev; int error; - int nerror; + int nagain, nerror; int i; if ((mode != LIO_NOWAIT) && (mode != LIO_WAIT)) @@ -2200,12 +2200,15 @@ kern_lio_listio(struct thread *td, int mode, struct ai /* * Get pointers to the list of I/O requests. */ + nagain = 0; nerror = 0; for (i = 0; i < nent; i++) { job = acb_list[i]; if (job != NULL) { error = aio_aqueue(td, job, lj, LIO_NOP, ops); - if (error != 0) + if (error == EAGAIN) + nagain++; + else if (error != 0) nerror++; } } @@ -2252,7 +2255,10 @@ kern_lio_listio(struct thread *td, int mode, struct ai if (nerror) return (EIO); - return (error); + else if (nagain) + return (EAGAIN); + else + return (error); } /* syscall - list directed I/O (REALTIME) */ Modified: head/tests/sys/aio/Makefile ============================================================================== --- head/tests/sys/aio/Makefile Mon Apr 16 18:07:51 2018 (r332630) +++ head/tests/sys/aio/Makefile Mon Apr 16 18:12:15 2018 (r332631) @@ -6,6 +6,8 @@ ATF_TESTS_C+= aio_test ATF_TESTS_C+= lio_test TEST_METADATA.aio_test+= timeout="30" TEST_METADATA.lio_test+= timeout="10" +# Some lio_test testcases involve system resource limitations, so cannot run concurrently +TEST_METADATA.lio_test+= is_exclusive=true PLAIN_TESTS_C+= aio_kqueue_test PLAIN_TESTS_C+= lio_kqueue_test Modified: head/tests/sys/aio/lio_test.c ============================================================================== --- head/tests/sys/aio/lio_test.c Mon Apr 16 18:07:51 2018 (r332630) +++ head/tests/sys/aio/lio_test.c Mon Apr 16 18:12:15 2018 (r332631) @@ -30,10 +30,13 @@ #include <sys/event.h> #include <aio.h> +#include <fcntl.h> #include <semaphore.h> +#include <stdlib.h> #include <atf-c.h> +#include "local.h" #include "freebsd_test_suite/macros.h" static sem_t completions; @@ -51,6 +54,73 @@ thr_handler(union sigval sv __unused) ATF_REQUIRE_EQ(0, sem_post(&completions)); } +/* + * If lio_listio is unable to enqueue any requests at all, it should return + * EAGAIN. + */ +ATF_TC_WITHOUT_HEAD(lio_listio_eagain_kevent); +ATF_TC_BODY(lio_listio_eagain_kevent, tc) +{ + int fd, i, j, kq, max_queue_per_proc, ios_per_call; + size_t max_queue_per_proc_size; + struct aiocb *aiocbs[2]; + struct aiocb **list[2]; + struct sigevent sev[2]; + char *buffer; + const char *path="tempfile"; + void *udata[2]; + + ATF_REQUIRE_KERNEL_MODULE("aio"); + ATF_REQUIRE_UNSAFE_AIO(); + + max_queue_per_proc_size = sizeof(max_queue_per_proc); + ATF_REQUIRE_EQ(sysctlbyname("vfs.aio.max_aio_queue_per_proc", + &max_queue_per_proc, &max_queue_per_proc_size, NULL, 0), 0); + ios_per_call = max_queue_per_proc; + + fd = open(path, O_RDWR|O_CREAT, 0666); + ATF_REQUIRE(fd >= 0); + + kq = kqueue(); + ATF_REQUIRE(kq > 0); + + buffer = calloc(1, 4096); + ATF_REQUIRE(buffer != NULL); + + /* + * Call lio_listio twice, each with the maximum number of operations. + * The first call should succeed and the second should fail. + */ + for (i = 0; i < 2; i++) { + aiocbs[i] = calloc(ios_per_call, sizeof(struct aiocb)); + ATF_REQUIRE(aiocbs[i] != NULL); + list[i] = calloc(ios_per_call, sizeof(struct aiocb*)); + ATF_REQUIRE(list[i] != NULL); + udata[i] = (void*)((caddr_t)0xdead0000 + i); + sev[i].sigev_notify = SIGEV_KEVENT; + sev[i].sigev_notify_kqueue = kq; + sev[i].sigev_value.sival_ptr = udata[i]; + for (j = 0; j < ios_per_call; j++) { + aiocbs[i][j].aio_fildes = fd; + aiocbs[i][j].aio_offset = (i * ios_per_call + j) * 4096; + aiocbs[i][j].aio_buf = buffer; + aiocbs[i][j].aio_nbytes = 4096; + aiocbs[i][j].aio_lio_opcode = LIO_WRITE; + list[i][j] = &aiocbs[i][j]; + } + } + + ATF_REQUIRE_EQ(0, lio_listio(LIO_NOWAIT, list[0], ios_per_call, &sev[0])); + ATF_REQUIRE_EQ(-1, lio_listio(LIO_NOWAIT, list[1], ios_per_call, &sev[1])); + /* + * The second lio_listio call should fail with EAGAIN. Bad timing may + * mean that some requests did get enqueued, but the result should + * still be EAGAIN. + */ + ATF_REQUIRE_EQ(errno, EAGAIN); +} + + /* With LIO_WAIT, an empty lio_listio should return immediately */ ATF_TC_WITHOUT_HEAD(lio_listio_empty_wait); ATF_TC_BODY(lio_listio_empty_wait, tc) @@ -136,6 +206,7 @@ ATF_TC_BODY(lio_listio_empty_nowait_thread, tc) ATF_TP_ADD_TCS(tp) { + ATF_TP_ADD_TC(tp, lio_listio_eagain_kevent); ATF_TP_ADD_TC(tp, lio_listio_empty_nowait_kevent); ATF_TP_ADD_TC(tp, lio_listio_empty_nowait_signal); ATF_TP_ADD_TC(tp, lio_listio_empty_nowait_thread); _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
