The transparent hugepage Linux-specific memory advisory has potentially significant implications for how the memory management behaves. Add a new mmap specific option that enables private TLP mmap mode when set so we can test running fio with anonymous memory (i.e. mmap /dev/zero).
Signed-off-by: Keith Busch <[email protected]> --- engines/mmap.c | 39 ++++++++++++++++++++++++++++++++++++--- optgroup.h | 2 ++ 2 files changed, 38 insertions(+), 3 deletions(-) diff --git a/engines/mmap.c b/engines/mmap.c index 308b4665..7bca6c20 100644 --- a/engines/mmap.c +++ b/engines/mmap.c @@ -11,6 +11,7 @@ #include <sys/mman.h> #include "../fio.h" +#include "../optgroup.h" #include "../verify.h" /* @@ -26,6 +27,26 @@ struct fio_mmap_data { off_t mmap_off; }; +struct mmap_options { + void *pad; + unsigned int thp; +}; + +static struct fio_option options[] = { + { + .name = "thp", + .lname = "Transparent Huge Pages", + .type = FIO_OPT_INT, + .off1 = offsetof(struct mmap_options, thp), + .help = "Memory Advise Huge Page", + .category = FIO_OPT_C_ENGINE, + .group = FIO_OPT_G_MMAP, + }, + { + .name = NULL, + }, +}; + static bool fio_madvise_file(struct thread_data *td, struct fio_file *f, size_t length) @@ -54,7 +75,8 @@ static int fio_mmap_file(struct thread_data *td, struct fio_file *f, size_t length, off_t off) { struct fio_mmap_data *fmd = FILE_ENG_DATA(f); - int flags = 0; + struct mmap_options *o = td->eo; + int flags = 0, shared = MAP_SHARED; if (td_rw(td) && !td->o.verify_only) flags = PROT_READ | PROT_WRITE; @@ -66,7 +88,12 @@ static int fio_mmap_file(struct thread_data *td, struct fio_file *f, } else flags = PROT_READ; - fmd->mmap_ptr = mmap(NULL, length, flags, MAP_SHARED, f->fd, off); +#if FIO_OS==os_linux + if (o->thp) + shared = MAP_PRIVATE; +#endif + + fmd->mmap_ptr = mmap(NULL, length, flags, shared, f->fd, off); if (fmd->mmap_ptr == MAP_FAILED) { fmd->mmap_ptr = NULL; td_verror(td, errno, "mmap"); @@ -146,6 +173,7 @@ static int fio_mmapio_prep(struct thread_data *td, struct io_u *io_u) { struct fio_file *f = io_u->file; struct fio_mmap_data *fmd = FILE_ENG_DATA(f); + struct mmap_options *o = td->eo; int ret; /* @@ -170,10 +198,13 @@ static int fio_mmapio_prep(struct thread_data *td, struct io_u *io_u) if (ret) return ret; } - done: io_u->mmap_data = fmd->mmap_ptr + io_u->offset - fmd->mmap_off - f->file_offset; +#if FIO_OS==os_linux + if (o->thp) + madvise(io_u->mmap_data, fmd->mmap_sz, MADV_HUGEPAGE); +#endif return 0; } @@ -275,6 +306,8 @@ static struct ioengine_ops ioengine = { .close_file = fio_mmapio_close_file, .get_file_size = generic_get_file_size, .flags = FIO_SYNCIO | FIO_NOEXTEND, + .options = options, + .option_struct_size = sizeof(struct mmap_options), }; static void fio_init fio_mmapio_register(void) diff --git a/optgroup.h b/optgroup.h index adf4d09b..bf1bb036 100644 --- a/optgroup.h +++ b/optgroup.h @@ -61,6 +61,7 @@ enum opt_category_group { __FIO_OPT_G_MTD, __FIO_OPT_G_HDFS, __FIO_OPT_G_SG, + __FIO_OPT_G_MMAP, __FIO_OPT_G_NR, FIO_OPT_G_RATE = (1ULL << __FIO_OPT_G_RATE), @@ -97,6 +98,7 @@ enum opt_category_group { FIO_OPT_G_MTD = (1ULL << __FIO_OPT_G_MTD), FIO_OPT_G_HDFS = (1ULL << __FIO_OPT_G_HDFS), FIO_OPT_G_SG = (1ULL << __FIO_OPT_G_SG), + FIO_OPT_G_MMAP = (1ULL << __FIO_OPT_G_MMAP), FIO_OPT_G_INVALID = (1ULL << __FIO_OPT_G_NR), }; -- 2.14.4
