diff options
| author | Paul Gortmaker <paul.gortmaker@windriver.com> | 2011-02-20 22:05:20 -0500 |
|---|---|---|
| committer | Paul Gortmaker <paul.gortmaker@windriver.com> | 2011-02-20 22:05:20 -0500 |
| commit | 348f94bbb939e2bf5a24495874e30de35076519e (patch) | |
| tree | 49589bcab80be1364bb06491183c5f68337a981e | |
| parent | 6b10a5b34a245ec3079362635b43d078c59da6c2 (diff) | |
| download | rt-patches-348f94bbb939e2bf5a24495874e30de35076519e.tar.gz | |
percpu: prefix strip breaks __mmdrop_delayed (Nasty!)v2.6.33-4341-gc1dcb4bv2.6.33-4316-g60f8a8dv2.6.33-4313-gb037bbav2.6.33-4264-ga03696ev2.6.33-4252-g0a135ba
At the integration of RT onto v2.6.33-4252-g0a135ba, bad things
happen, and __mmdrop_delayed oopses the kernel. Turns out that
the removal of per_cpu__ from all the names of the percpu vars
causes an implicit name conflict, where the percpu var gets
shadowed by a local var with a poorly chosen (i.e. identical)
name string. Add the cpu_ prefix to the local to indicate it
is tied to the current CPU and is not meant to be the percpu one.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
| -rw-r--r-- | cpu-hotplug-Don-t-wake-up-the-desched-thread-from-id.patch | 10 | ||||
| -rw-r--r-- | sched-mmdrop-needs-to-be-delayed-on-rt.patch | 12 |
2 files changed, 13 insertions, 9 deletions
diff --git a/cpu-hotplug-Don-t-wake-up-the-desched-thread-from-id.patch b/cpu-hotplug-Don-t-wake-up-the-desched-thread-from-id.patch index 7a6d634..dfd6b81 100644 --- a/cpu-hotplug-Don-t-wake-up-the-desched-thread-from-id.patch +++ b/cpu-hotplug-Don-t-wake-up-the-desched-thread-from-id.patch @@ -79,15 +79,15 @@ index 6dc8e27..74192aa 100644 -void __mmdrop_delayed(struct mm_struct *mm) +void __mmdrop_delayed(struct mm_struct *mm, int wake) { - struct task_struct *desched_task; + struct task_struct *cpu_desched_task; struct list_head *head; @@ -1839,7 +1841,7 @@ void __mmdrop_delayed(struct mm_struct *mm) head = &get_cpu_var(delayed_drop_list); list_add_tail(&mm->delayed_drop, head); - desched_task = __get_cpu_var(desched_task); -- if (desched_task) -+ if (desched_task && wake) - wake_up_process(desched_task); + cpu_desched_task = __get_cpu_var(desched_task); +- if (cpu_desched_task) ++ if (cpu_desched_task && wake) + wake_up_process(cpu_desched_task); put_cpu_var(delayed_drop_list); } @@ -1854,13 +1856,16 @@ static void takeover_delayed_drop(int hotcpu) diff --git a/sched-mmdrop-needs-to-be-delayed-on-rt.patch b/sched-mmdrop-needs-to-be-delayed-on-rt.patch index bf6b222..e8e97cf 100644 --- a/sched-mmdrop-needs-to-be-delayed-on-rt.patch +++ b/sched-mmdrop-needs-to-be-delayed-on-rt.patch @@ -5,6 +5,10 @@ Subject: [PATCH] sched: mmdrop needs to be delayed on -rt commit 5b6e135f5e1e9e5586ad69e35c96494a4b413a00 in tip. +[PG: upstream per_cpu__ prefix removal dd17c8f729) caused an implicit + (and hard to spot) shadowing of the percpu desched_task with a + local var of the same name in __mmdrop_delayed, so add cpu_ prefix] + Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> @@ -154,14 +158,14 @@ index c12e53a..c49f839 100644 + */ +void __mmdrop_delayed(struct mm_struct *mm) +{ -+ struct task_struct *desched_task; ++ struct task_struct *cpu_desched_task; + struct list_head *head; + + head = &get_cpu_var(delayed_drop_list); + list_add_tail(&mm->delayed_drop, head); -+ desched_task = __get_cpu_var(desched_task); -+ if (desched_task) -+ wake_up_process(desched_task); ++ cpu_desched_task = __get_cpu_var(desched_task); ++ if (cpu_desched_task) ++ wake_up_process(cpu_desched_task); + put_cpu_var(delayed_drop_list); +} + |