The patch titled
uml: irq locking commentary
has been removed from the -mm tree. Its filename was
uml-irq-locking-commentary.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
Subject: uml: irq locking commentary
From: Jeff Dike <jdike@xxxxxxxxxxx>
Locking commentary.
Signed-off-by: Jeff Dike <jdike@xxxxxxxxxxxxxxx>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@xxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/um/kernel/irq.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)
diff -puN arch/um/kernel/irq.c~uml-irq-locking-commentary arch/um/kernel/irq.c
--- a/arch/um/kernel/irq.c~uml-irq-locking-commentary
+++ a/arch/um/kernel/irq.c
@@ -78,6 +78,14 @@ skip:
return 0;
}
+/*
+ * This list is accessed under irq_lock, except in sigio_handler,
+ * where it is safe from being modified. IRQ handlers won't change it -
+ * if an IRQ source has vanished, it will be freed by free_irqs just
+ * before returning from sigio_handler. That will process a separate
+ * list of irqs to free, with its own locking, coming back here to
+ * remove list elements, taking the irq_lock to do so.
+ */
static struct irq_fd *active_fds = NULL;
static struct irq_fd **last_irq_ptr = &active_fds;
@@ -243,6 +251,7 @@ void free_irq_by_fd(int fd)
free_irq_by_cb(same_fd, &fd);
}
+/* Must be called with irq_lock held */
static struct irq_fd *find_irq_by_fd(int fd, int irqnum, int *index_out)
{
struct irq_fd *irq;
@@ -308,6 +317,12 @@ void deactivate_fd(int fd, int irqnum)
ignore_sigio_fd(fd);
}
+/*
+ * Called just before shutdown in order to provide a clean exec
+ * environment in case the system is rebooting. No locking because
+ * that would cause a pointless shutdown hang if something hadn't
+ * released the lock.
+ */
int deactivate_all_fds(void)
{
struct irq_fd *irq;
_
Patches currently in -mm which might be from jdike@xxxxxxxxxxx are
origin.patch
uml-hostfs-style-fixes.patch
uml-an-idle-system-should-have-zero-load-average.patch
remove-tas.patch
x86-create-asm-cmpxchgh.patch
uml-network-and-pcap-cleanup.patch
uml-pcap-devices-should-get-macs-from-command-line.patch
-
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
