summaryrefslogtreecommitdiffstats
path: root/arch/um/drivers/line.c
diff options
context:
space:
mode:
authorAnton Ivanov <anton.ivanov@cambridgegreys.com>2018-09-25 09:47:13 +0200
committerRichard Weinberger <richard@nod.at>2018-10-29 22:34:16 +0100
commit917e2fd2c53eb3c4162f5397555cbd394390d4bc (patch)
treeaf60a713b762c7915fa44792ed9ef4f25ff766be /arch/um/drivers/line.c
parentum: trap: fix spelling mistake, EACCESS -> EACCES (diff)
downloadlinux-917e2fd2c53eb3c4162f5397555cbd394390d4bc.tar.xz
linux-917e2fd2c53eb3c4162f5397555cbd394390d4bc.zip
um: Make line/tty semantics use true write IRQ
This fixes a long standing bug where large amounts of output could freeze the tty (most commonly seen on stdio console). While the bug has always been there it became more pronounced after moving to the new interrupt controller. The line semantics are now changed to have true IRQ write semantics which should further improve the tty/line subsystem stability and performance Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com> Signed-off-by: Richard Weinberger <richard@nod.at>
Diffstat (limited to 'arch/um/drivers/line.c')
-rw-r--r--arch/um/drivers/line.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/um/drivers/line.c b/arch/um/drivers/line.c
index 8d80b27502e6..7e524efed584 100644
--- a/arch/um/drivers/line.c
+++ b/arch/um/drivers/line.c
@@ -261,7 +261,7 @@ static irqreturn_t line_write_interrupt(int irq, void *data)
if (err == 0) {
spin_unlock(&line->lock);
return IRQ_NONE;
- } else if (err < 0) {
+ } else if ((err < 0) && (err != -EAGAIN)) {
line->head = line->buffer;
line->tail = line->buffer;
}
@@ -284,7 +284,7 @@ int line_setup_irq(int fd, int input, int output, struct line *line, void *data)
if (err)
return err;
if (output)
- err = um_request_irq(driver->write_irq, fd, IRQ_NONE,
+ err = um_request_irq(driver->write_irq, fd, IRQ_WRITE,
line_write_interrupt, IRQF_SHARED,
driver->write_irq_name, data);
return err;