admin/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2025-12-07 20:06:24 +00:00
Code Issues Packages Projects Releases Wiki Activity

sched_ext: Refactor lockup handlers into handle_lockup()

Browse Source 
scx_rcu_cpu_stall() and scx_softlockup() share the same pattern: check if the
scheduler is enabled under RCU read lock and trigger an error if so. Extract
the common pattern into handle_lockup() helper. Add scx_verror() macro and use
guard(rcu)().

This simplifies both handlers, reduces code duplication, and prepares for
hardlockup handling.

Reviewed-by: Dan Schatzberg <schatzberg.dan@gmail.com>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
Cc: Emil Tsalapatis <etsal@meta.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Tejun Heo
2025-11-11 09:18:10 -10:00
parent f2fe382e1f
commit 4ba54a6cbd
1 changed files with 29 additions and 44 deletions
Download Patch File Download Diff File Expand all files Collapse all files

73
kernel/sched/ext.c
View File

@@ -192,6 +192,7 @@ static __printf(4, 5) bool scx_exit(struct scx_sched *sch,
}
#define scx_error(sch, fmt, args...) scx_exit((sch), SCX_EXIT_ERROR, 0, fmt, ##args)
#define scx_verror(sch, fmt, args) scx_vexit((sch), SCX_EXIT_ERROR, 0, fmt, args)
#define SCX_HAS_OP(sch, op) test_bit(SCX_OP_IDX(op), (sch)->has_op)
@@ -3654,6 +3655,29 @@ bool scx_allow_ttwu_queue(const struct task_struct *p)
return false;
}
static __printf(1, 2) bool handle_lockup(const char *fmt, ...)
{
struct scx_sched *sch;
va_list args;
guard(rcu)();
sch = rcu_dereference(scx_root);
if (unlikely(!sch))
return false;
switch (scx_enable_state()) {
case SCX_ENABLING:
case SCX_ENABLED:
va_start(args, fmt);
scx_verror(sch, fmt, args);
va_end(args);
return true;
default:
return false;
}
}
/**
* scx_rcu_cpu_stall - sched_ext RCU CPU stall handler
*
@@ -3664,29 +3688,7 @@ bool scx_allow_ttwu_queue(const struct task_struct *p)
*/
bool scx_rcu_cpu_stall(void)
{
struct scx_sched *sch;
rcu_read_lock();
sch = rcu_dereference(scx_root);
if (unlikely(!sch)) {
rcu_read_unlock();
return false;
}
switch (scx_enable_state()) {
case SCX_ENABLING:
case SCX_ENABLED:
break;
default:
rcu_read_unlock();
return false;
}
scx_error(sch, "RCU CPU stall detected!");
rcu_read_unlock();
return true;
return handle_lockup("RCU CPU stall detected!");
}
/**
@@ -3701,28 +3703,11 @@ bool scx_rcu_cpu_stall(void)
*/
void scx_softlockup(u32 dur_s)
{
struct scx_sched *sch;
if (!handle_lockup("soft lockup - CPU %d stuck for %us", smp_processor_id(), dur_s))
return;
rcu_read_lock();
sch = rcu_dereference(scx_root);
if (unlikely(!sch))
goto out_unlock;
switch (scx_enable_state()) {
case SCX_ENABLING:
case SCX_ENABLED:
break;
default:
goto out_unlock;
}
printk_deferred(KERN_ERR "sched_ext: Soft lockup - CPU%d stuck for %us, disabling \"%s\"\n",
smp_processor_id(), dur_s, scx_root->ops.name);
scx_error(sch, "soft lockup - CPU#%d stuck for %us", smp_processor_id(), dur_s);
out_unlock:
rcu_read_unlock();
printk_deferred(KERN_ERR "sched_ext: Soft lockup - CPU %d stuck for %us, disabling BPF scheduler\n",
smp_processor_id(), dur_s);
}
/**