diff options
| author |  Anton Ivanov <aivanov@kot-begemot.co.uk>
| 2016-11-09 20:43:25 +0000 |
|---|---|---|
| committer |  Richard Weinberger <richard@nod.at>
| 2016-12-14 22:46:55 +0100 |
| commit | f88f0bdfc32f3d1e2fd03ec8a7f7b456df4db725 (patch) | |
| tree | 7eed7ad5a2f795f8b45187db4955eff9c5ef049a /arch/um/drivers/ubd_user.c | |
| parent | Linux 4.9 (diff) | |
| download | linux-f88f0bdfc32f3d1e2fd03ec8a7f7b456df4db725.tar.gz linux-f88f0bdfc32f3d1e2fd03ec8a7f7b456df4db725.tar.bz2 linux-f88f0bdfc32f3d1e2fd03ec8a7f7b456df4db725.zip | |
um: UBD Improvements
UBD at present is extremely slow because it handles only
one request at a time in the IO thread and IRQ handler.
The single request at a time is replaced by handling multiple
requests as well as necessary workarounds for short reads/writes.
Resulting performance improvement in disk IO - 30%
Signed-off-by: Anton Ivanov <aivanov@kot-begemot.co.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
Diffstat (limited to 'arch/um/drivers/ubd_user.c')
| -rw-r--r-- | arch/um/drivers/ubd_user.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/arch/um/drivers/ubd_user.c b/arch/um/drivers/ubd_user.c index e376f9b9c68d..6f744794d141 100644 --- a/arch/um/drivers/ubd_user.c +++ b/arch/um/drivers/ubd_user.c @@ -1,4 +1,5 @@ -/* +/* + * Copyright (C) 2016 Anton Ivanov (aivanov@brocade.com) * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com) * Copyright (C) 2001 Ridgerun,Inc (glonnon@ridgerun.com) * Licensed under the GPL @@ -20,6 +21,9 @@ #include "ubd.h" #include <os.h> +#include <poll.h> + +struct pollfd kernel_pollfd; int start_io_thread(unsigned long sp, int *fd_out) { @@ -32,9 +36,12 @@ int start_io_thread(unsigned long sp, int *fd_out) } kernel_fd = fds[0]; + kernel_pollfd.fd = kernel_fd; + kernel_pollfd.events = POLLIN; *fd_out = fds[1]; err = os_set_fd_block(*fd_out, 0); + err = os_set_fd_block(kernel_fd, 0); if (err) { printk("start_io_thread - failed to set nonblocking I/O.\n"); goto out_close; @@ -57,3 +64,15 @@ int start_io_thread(unsigned long sp, int *fd_out) out: return err; } + +int ubd_read_poll(int timeout) +{ + kernel_pollfd.events = POLLIN; + return poll(&kernel_pollfd, 1, timeout); +} +int ubd_write_poll(int timeout) +{ + kernel_pollfd.events = POLLOUT; + return poll(&kernel_pollfd, 1, timeout); +} + |