From 5da784cce4308ae10a79e3c8c41b13fb9568e4e0 Mon Sep 17 00:00:00 2001 From: Constantine Shulyupin Date: Thu, 6 Sep 2018 15:37:06 +0300 Subject: fuse: add max_pages to init_out Replace FUSE_MAX_PAGES_PER_REQ with the configurable parameter max_pages to improve performance. Old RFC with detailed description of the problem and many fixes by Mitsuo Hayasaka (mitsuo.hayasaka.hu@hitachi.com): - https://lkml.org/lkml/2012/7/5/136 We've encountered performance degradation and fixed it on a big and complex virtual environment. Environment to reproduce degradation and improvement: 1. Add lag to user mode FUSE Add nanosleep(&(struct timespec){ 0, 1000 }, NULL); to xmp_write_buf in passthrough_fh.c 2. patch UM fuse with configurable max_pages parameter. The patch will be provided latter. 3. run test script and perform test on tmpfs fuse_test() { cd /tmp mkdir -p fusemnt passthrough_fh -o max_pages=$1 /tmp/fusemnt grep fuse /proc/self/mounts dd conv=fdatasync oflag=dsync if=/dev/zero of=fusemnt/tmp/tmp \ count=1K bs=1M 2>&1 | grep -v records rm fusemnt/tmp/tmp killall passthrough_fh } Test results: passthrough_fh /tmp/fusemnt fuse.passthrough_fh \ rw,nosuid,nodev,relatime,user_id=0,group_id=0 0 0 1073741824 bytes (1.1 GB) copied, 1.73867 s, 618 MB/s passthrough_fh /tmp/fusemnt fuse.passthrough_fh \ rw,nosuid,nodev,relatime,user_id=0,group_id=0,max_pages=256 0 0 1073741824 bytes (1.1 GB) copied, 1.15643 s, 928 MB/s Obviously with bigger lag the difference between 'before' and 'after' will be more significant. Mitsuo Hayasaka, in 2012 (https://lkml.org/lkml/2012/7/5/136), observed improvement from 400-550 to 520-740. Signed-off-by: Constantine Shulyupin Signed-off-by: Miklos Szeredi --- fs/fuse/file.c | 59 +++++++++++++++++++++++++++++----------------------------- 1 file changed, 30 insertions(+), 29 deletions(-) (limited to 'fs/fuse/file.c') diff --git a/fs/fuse/file.c b/fs/fuse/file.c index b10d14baeb1f..035843b501fe 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -850,11 +850,11 @@ static int fuse_readpages_fill(void *_data, struct page *page) fuse_wait_on_page_writeback(inode, page->index); if (req->num_pages && - (req->num_pages == FUSE_MAX_PAGES_PER_REQ || + (req->num_pages == fc->max_pages || (req->num_pages + 1) * PAGE_SIZE > fc->max_read || req->pages[req->num_pages - 1]->index + 1 != page->index)) { - int nr_alloc = min_t(unsigned, data->nr_pages, - FUSE_MAX_PAGES_PER_REQ); + unsigned int nr_alloc = min_t(unsigned int, data->nr_pages, + fc->max_pages); fuse_send_readpages(req, data->file); if (fc->async_read) req = fuse_get_req_for_background(fc, nr_alloc); @@ -889,7 +889,7 @@ static int fuse_readpages(struct file *file, struct address_space *mapping, struct fuse_conn *fc = get_fuse_conn(inode); struct fuse_fill_data data; int err; - int nr_alloc = min_t(unsigned, nr_pages, FUSE_MAX_PAGES_PER_REQ); + unsigned int nr_alloc = min_t(unsigned int, nr_pages, fc->max_pages); err = -EIO; if (is_bad_inode(inode)) @@ -1104,12 +1104,13 @@ static ssize_t fuse_fill_write_pages(struct fuse_req *req, return count > 0 ? count : err; } -static inline unsigned fuse_wr_pages(loff_t pos, size_t len) +static inline unsigned int fuse_wr_pages(loff_t pos, size_t len, + unsigned int max_pages) { - return min_t(unsigned, + return min_t(unsigned int, ((pos + len - 1) >> PAGE_SHIFT) - (pos >> PAGE_SHIFT) + 1, - FUSE_MAX_PAGES_PER_REQ); + max_pages); } static ssize_t fuse_perform_write(struct kiocb *iocb, @@ -1131,7 +1132,8 @@ static ssize_t fuse_perform_write(struct kiocb *iocb, do { struct fuse_req *req; ssize_t count; - unsigned nr_pages = fuse_wr_pages(pos, iov_iter_count(ii)); + unsigned int nr_pages = fuse_wr_pages(pos, iov_iter_count(ii), + fc->max_pages); req = fuse_get_req(fc, nr_pages); if (IS_ERR(req)) { @@ -1321,11 +1323,6 @@ static int fuse_get_user_pages(struct fuse_req *req, struct iov_iter *ii, return ret < 0 ? ret : 0; } -static inline int fuse_iter_npages(const struct iov_iter *ii_p) -{ - return iov_iter_npages(ii_p, FUSE_MAX_PAGES_PER_REQ); -} - ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter, loff_t *ppos, int flags) { @@ -1345,9 +1342,10 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter, int err = 0; if (io->async) - req = fuse_get_req_for_background(fc, fuse_iter_npages(iter)); + req = fuse_get_req_for_background(fc, iov_iter_npages(iter, + fc->max_pages)); else - req = fuse_get_req(fc, fuse_iter_npages(iter)); + req = fuse_get_req(fc, iov_iter_npages(iter, fc->max_pages)); if (IS_ERR(req)) return PTR_ERR(req); @@ -1392,9 +1390,10 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter, fuse_put_request(fc, req); if (io->async) req = fuse_get_req_for_background(fc, - fuse_iter_npages(iter)); + iov_iter_npages(iter, fc->max_pages)); else - req = fuse_get_req(fc, fuse_iter_npages(iter)); + req = fuse_get_req(fc, iov_iter_npages(iter, + fc->max_pages)); if (IS_ERR(req)) break; } @@ -1823,7 +1822,7 @@ static int fuse_writepages_fill(struct page *page, is_writeback = fuse_page_is_writeback(inode, page->index); if (req && req->num_pages && - (is_writeback || req->num_pages == FUSE_MAX_PAGES_PER_REQ || + (is_writeback || req->num_pages == fc->max_pages || (req->num_pages + 1) * PAGE_SIZE > fc->max_write || data->orig_pages[req->num_pages - 1]->index + 1 != page->index)) { fuse_writepages_send(data); @@ -1851,7 +1850,7 @@ static int fuse_writepages_fill(struct page *page, struct fuse_inode *fi = get_fuse_inode(inode); err = -ENOMEM; - req = fuse_request_alloc_nofs(FUSE_MAX_PAGES_PER_REQ); + req = fuse_request_alloc_nofs(fc->max_pages); if (!req) { __free_page(tmp_page); goto out_unlock; @@ -1908,6 +1907,7 @@ static int fuse_writepages(struct address_space *mapping, struct writeback_control *wbc) { struct inode *inode = mapping->host; + struct fuse_conn *fc = get_fuse_conn(inode); struct fuse_fill_wb_data data; int err; @@ -1920,7 +1920,7 @@ static int fuse_writepages(struct address_space *mapping, data.ff = NULL; err = -ENOMEM; - data.orig_pages = kcalloc(FUSE_MAX_PAGES_PER_REQ, + data.orig_pages = kcalloc(fc->max_pages, sizeof(struct page *), GFP_NOFS); if (!data.orig_pages) @@ -2391,10 +2391,11 @@ static int fuse_copy_ioctl_iovec_old(struct iovec *dst, void *src, } /* Make sure iov_length() won't overflow */ -static int fuse_verify_ioctl_iov(struct iovec *iov, size_t count) +static int fuse_verify_ioctl_iov(struct fuse_conn *fc, struct iovec *iov, + size_t count) { size_t n; - u32 max = FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT; + u32 max = fc->max_pages << PAGE_SHIFT; for (n = 0; n < count; n++, iov++) { if (iov->iov_len > (size_t) max) @@ -2518,7 +2519,7 @@ long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg, BUILD_BUG_ON(sizeof(struct fuse_ioctl_iovec) * FUSE_IOCTL_MAX_IOV > PAGE_SIZE); err = -ENOMEM; - pages = kcalloc(FUSE_MAX_PAGES_PER_REQ, sizeof(pages[0]), GFP_KERNEL); + pages = kcalloc(fc->max_pages, sizeof(pages[0]), GFP_KERNEL); iov_page = (struct iovec *) __get_free_page(GFP_KERNEL); if (!pages || !iov_page) goto out; @@ -2557,7 +2558,7 @@ long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg, /* make sure there are enough buffer pages and init request with them */ err = -ENOMEM; - if (max_pages > FUSE_MAX_PAGES_PER_REQ) + if (max_pages > fc->max_pages) goto out; while (num_pages < max_pages) { pages[num_pages] = alloc_page(GFP_KERNEL | __GFP_HIGHMEM); @@ -2644,11 +2645,11 @@ long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg, in_iov = iov_page; out_iov = in_iov + in_iovs; - err = fuse_verify_ioctl_iov(in_iov, in_iovs); + err = fuse_verify_ioctl_iov(fc, in_iov, in_iovs); if (err) goto out; - err = fuse_verify_ioctl_iov(out_iov, out_iovs); + err = fuse_verify_ioctl_iov(fc, out_iov, out_iovs); if (err) goto out; @@ -2839,9 +2840,9 @@ static void fuse_do_truncate(struct file *file) fuse_do_setattr(file_dentry(file), &attr, file); } -static inline loff_t fuse_round_up(loff_t off) +static inline loff_t fuse_round_up(struct fuse_conn *fc, loff_t off) { - return round_up(off, FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT); + return round_up(off, fc->max_pages << PAGE_SHIFT); } static ssize_t @@ -2870,7 +2871,7 @@ fuse_direct_IO(struct kiocb *iocb, struct iov_iter *iter) if (async_dio && iov_iter_rw(iter) != WRITE && offset + count > i_size) { if (offset >= i_size) return 0; - iov_iter_truncate(iter, fuse_round_up(i_size - offset)); + iov_iter_truncate(iter, fuse_round_up(ff->fc, i_size - offset)); count = iov_iter_count(iter); } -- cgit v1.2.3