From cef8c8b249023fb8129ae791e0998cbca771f96a Mon Sep 17 00:00:00 2001 From: yangyun50 <149988609+yangyun50@users.noreply.github.com> Date: Tue, 4 Jun 2024 19:50:48 +0800 Subject: Add support for no_interrupt (#956) The function fuse_session_process_buf_int() would do much things for FUSE_INTERRUPT requests, even there are no FUSE_INTERRUPT requests: 1. check every non-FUSE_INTERRUPT request and add these requests to the linked list(se->list) under a big lock(se->lock). 2. the function fuse_free_req() frees every request and remove them from the linked list(se->list) under a bing lock(se->lock). These operations are not meaningful when there are no FUSE_INTERRUPT requests, and have a great impact on the performance of fuse filesystem because the big lock for each request. In some cases, FUSE_INTERRUPT requests are infrequent, even none at all. Besides, the user-defined filesystem may do nothing for FUSE_INTERRUPT requests. And the kernel side has the option "no_interrupt" in struct fuse_conn. This kernel option can be enabled by return ENOSYS in libfuse for the reply of FUSE_INTERRUPT request. But I don't find the code to enable the "no_interrupt" kernel option in libfuse. So add the no_interrupt support, and when this operaion is enabled: 1. remove the useless locking operaions and list operations. 2. return ENOSYS for the reply of FUSE_INTERRUPT request to inform the kernel to disable FUSE_INTERRUPT request. --- example/cuse.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'example/cuse.c') diff --git a/example/cuse.c b/example/cuse.c index 0c0e7bc..6b33302 100644 --- a/example/cuse.c +++ b/example/cuse.c @@ -87,6 +87,14 @@ static int cusexmp_expand(size_t new_size) return 0; } +static void cusexmp_init(void *userdata, struct fuse_conn_info *conn) +{ + (void)userdata; + + /* Disable the receiving and processing of FUSE_INTERRUPT requests */ + conn->no_interrupt = 1; +} + static void cusexmp_open(fuse_req_t req, struct fuse_file_info *fi) { fuse_reply_open(req, fi); @@ -281,6 +289,7 @@ static int cusexmp_process_arg(void *data, const char *arg, int key, } static const struct cuse_lowlevel_ops cusexmp_clop = { + .init = cusexmp_init, .open = cusexmp_open, .read = cusexmp_read, .write = cusexmp_write, -- cgit v1.2.3