The original functionality was added back in:
1cee5e35f15 (kgdb: Add the ability to schedule a breakpoint via a tasklet)
However tasklets have long been deprecated as being too heavy on
the system by running in irq context - and this is not a performance
critical path. If a higher priority process wants to run, it must
wait for the tasklet to finish before doing so. Instead, generate
the breakpoint exception in process context.
Signed-off-by: Davidlohr Bueso <dbu...@suse.de>
---
Compile-tested only.
kernel/debug/debug_core.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index af6e8b4fb359..e1ff974c6b6f 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -119,7 +119,7 @@ static DEFINE_RAW_SPINLOCK(dbg_slave_lock);
*/
static atomic_t masters_in_kgdb;
static atomic_t slaves_in_kgdb;
-static atomic_t kgdb_break_tasklet_var;
+static atomic_t kgdb_break_work_var;
atomic_t kgdb_setting_breakpoint;
struct task_struct *kgdb_usethread;
@@ -1085,27 +1085,27 @@ static void kgdb_unregister_callbacks(void)
}
/*
- * There are times a tasklet needs to be used vs a compiled in
+ * There are times a workqueue needs to be used vs a compiled in
* break point so as to cause an exception outside a kgdb I/O module,
* such as is the case with kgdboe, where calling a breakpoint in the
* I/O driver itself would be fatal.
*/
-static void kgdb_tasklet_bpt(unsigned long ing)
+static void kgdb_work_bpt(struct work_struct *unused)
{
kgdb_breakpoint();
- atomic_set(&kgdb_break_tasklet_var, 0);
+ atomic_set(&kgdb_break_work_var, 0);
}
-static DECLARE_TASKLET_OLD(kgdb_tasklet_breakpoint, kgdb_tasklet_bpt);
+static DECLARE_WORK(kgdb_async_breakpoint, kgdb_work_bpt);
void kgdb_schedule_breakpoint(void)
{
- if (atomic_read(&kgdb_break_tasklet_var) ||
+ if (atomic_read(&kgdb_break_work_var) ||
atomic_read(&kgdb_active) != -1 ||
atomic_read(&kgdb_setting_breakpoint))
return;
- atomic_inc(&kgdb_break_tasklet_var);
- tasklet_schedule(&kgdb_tasklet_breakpoint);
+ atomic_inc(&kgdb_break_work_var);
+ schedule_work(&kgdb_async_breakpoint);
}
EXPORT_SYMBOL_GPL(kgdb_schedule_breakpoint);
--
2.26.2
