[tip:,irq/core] docs: locking: Discourage from calling disable_irq() in atomic
Commit Message
The following commit has been merged into the irq/core branch of tip:
Commit-ID: 379af13b31fa8a36ad4abd59a5c511f25c5d4d42
Gitweb: https://git.kernel.org/tip/379af13b31fa8a36ad4abd59a5c511f25c5d4d42
Author: Alexander Sverdlin <alexander.sverdlin@siemens.com>
AuthorDate: Mon, 12 Dec 2022 17:37:15 +01:00
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Wed, 11 Jan 2023 19:45:26 +01:00
docs: locking: Discourage from calling disable_irq() in atomic
Correct the example in the documentation so that disable_irq() is not being
called in atomic context.
disable_irq() calls sleeping synchronize_irq(), it's not allowed to call
them in atomic context.
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Manfred Spraul <manfred@colorfullife.com>
Cc: linux-doc@vger.kernel.org
Link: https://lore.kernel.org/lkml/87k02wbs2n.ffs@tglx/
Link: https://lore.kernel.org/r/20221212163715.830315-1-alexander.sverdlin@siemens.com
---
Documentation/kernel-hacking/locking.rst | 4 ++--
Documentation/translations/it_IT/kernel-hacking/locking.rst | 4 ++--
2 files changed, 4 insertions(+), 4 deletions(-)
@@ -1277,11 +1277,11 @@ Manfred Spraul points out that you can still do this, even if the data
is very occasionally accessed in user context or softirqs/tasklets. The
irq handler doesn't use a lock, and all other accesses are done as so::
- spin_lock(&lock);
+ mutex_lock(&lock);
disable_irq(irq);
...
enable_irq(irq);
- spin_unlock(&lock);
+ mutex_unlock(&lock);
The disable_irq() prevents the irq handler from running
(and waits for it to finish if it's currently running on other CPUs).
@@ -1307,11 +1307,11 @@ se i dati vengono occasionalmente utilizzati da un contesto utente o
da un'interruzione software. Il gestore d'interruzione non utilizza alcun
*lock*, e tutti gli altri accessi verranno fatti così::
- spin_lock(&lock);
+ mutex_lock(&lock);
disable_irq(irq);
...
enable_irq(irq);
- spin_unlock(&lock);
+ mutex_unlock(&lock);
La funzione disable_irq() impedisce al gestore d'interruzioni
d'essere eseguito (e aspetta che finisca nel caso fosse in esecuzione su