[tip:irq/core] irq/work: Improve the flag definitions

From: tip-bot for Bartosz Golaszewski
Date: Mon Jan 08 2018 - 15:40:01 EST


Commit-ID: 6baf9e67c9c5d738188b8490893c7e079d3deb7e
Gitweb: https://git.kernel.org/tip/6baf9e67c9c5d738188b8490893c7e079d3deb7e
Author: Bartosz Golaszewski <brgl@xxxxxxxx>
AuthorDate: Fri, 5 Jan 2018 05:19:56 +0100
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Mon, 8 Jan 2018 19:43:15 +0100

irq/work: Improve the flag definitions

IRQ_WORK_FLAGS is defined simply to 3UL. This is confusing as it
says nothing about its purpose. Define IRQ_WORK_FLAGS as a bitwise
OR of IRQ_WORK_PENDING and IRQ_WORK_BUSY and change its name to
IRQ_WORK_CLAIMED.

While we're at it: use the BIT() macro for all flags.

Signed-off-by: Bartosz Golaszewski <brgl@xxxxxxxx>
Signed-off-by: Frederic Weisbecker <frederic@xxxxxxxxxx>
Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/1515125996-21564-1-git-send-email-frederic@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
include/linux/irq_work.h | 11 +++++++----
kernel/irq_work.c | 2 +-
2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/include/linux/irq_work.h b/include/linux/irq_work.h
index 0e81035..b11fcdf 100644
--- a/include/linux/irq_work.h
+++ b/include/linux/irq_work.h
@@ -13,10 +13,13 @@
* busy NULL, 2 -> {free, claimed} : callback in progress, can be claimed
*/

-#define IRQ_WORK_PENDING 1UL
-#define IRQ_WORK_BUSY 2UL
-#define IRQ_WORK_FLAGS 3UL
-#define IRQ_WORK_LAZY 4UL /* Doesn't want IPI, wait for tick */
+#define IRQ_WORK_PENDING BIT(0)
+#define IRQ_WORK_BUSY BIT(1)
+
+/* Doesn't want IPI, wait for tick: */
+#define IRQ_WORK_LAZY BIT(2)
+
+#define IRQ_WORK_CLAIMED (IRQ_WORK_PENDING | IRQ_WORK_BUSY)

struct irq_work {
unsigned long flags;
diff --git a/kernel/irq_work.c b/kernel/irq_work.c
index 40e9d73..6b7cdf1 100644
--- a/kernel/irq_work.c
+++ b/kernel/irq_work.c
@@ -36,7 +36,7 @@ static bool irq_work_claim(struct irq_work *work)
*/
flags = work->flags & ~IRQ_WORK_PENDING;
for (;;) {
- nflags = flags | IRQ_WORK_FLAGS;
+ nflags = flags | IRQ_WORK_CLAIMED;
oflags = cmpxchg(&work->flags, flags, nflags);
if (oflags == flags)
break;