Commit fc1fcebe authored by Tejun Heo's avatar Tejun Heo
Browse files

sched_ext: Remove SCX_OPS_PREPPING 



The distinction between SCX_OPS_PREPPING and SCX_OPS_ENABLING is not used
anywhere and only adds confusion. Drop SCX_OPS_PREPPING.

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent 1bbcfe62

kernel/sched/ext.c

+7 −22
Original line number Diff line number Diff line
@@ -779,7 +779,6 @@ enum scx_tg_flags { 
};



enum scx_ops_enable_state {

	SCX_OPS_PREPPING,

	SCX_OPS_ENABLING,

	SCX_OPS_ENABLED,

	SCX_OPS_DISABLING,
@@ -787,7 +786,6 @@ enum scx_ops_enable_state { 
};



static const char *scx_ops_enable_state_str[] = {

	[SCX_OPS_PREPPING]	= "prepping",

	[SCX_OPS_ENABLING]	= "enabling",

	[SCX_OPS_ENABLED]	= "enabled",

	[SCX_OPS_DISABLING]	= "disabling",
@@ -5016,12 +5014,12 @@ static int scx_ops_enable(struct sched_ext_ops *ops, struct bpf_link *link) 
	}



	/*

	 * Set scx_ops, transition to PREPPING and clear exit info to arm the

	 * Set scx_ops, transition to ENABLING and clear exit info to arm the

	 * disable path. Failure triggers full disabling from here on.

	 */

	scx_ops = *ops;



	WARN_ON_ONCE(scx_ops_set_enable_state(SCX_OPS_PREPPING) !=

	WARN_ON_ONCE(scx_ops_set_enable_state(SCX_OPS_ENABLING) !=

		     SCX_OPS_DISABLED);



	atomic_set(&scx_exit_kind, SCX_EXIT_NONE);
@@ -5174,23 +5172,6 @@ static int scx_ops_enable(struct sched_ext_ops *ops, struct bpf_link *link) 
	 */

	preempt_disable();



	/*

	 * From here on, the disable path must assume that tasks have ops

	 * enabled and need to be recovered.

	 *

	 * Transition to ENABLING fails iff the BPF scheduler has already

	 * triggered scx_bpf_error(). Returning an error code here would lose

	 * the recorded error information. Exit indicating success so that the

	 * error is notified through ops.exit() with all the details.

	 */

	if (!scx_ops_tryset_enable_state(SCX_OPS_ENABLING, SCX_OPS_PREPPING)) {

		preempt_enable();

		spin_unlock_irq(&scx_tasks_lock);

		WARN_ON_ONCE(atomic_read(&scx_exit_kind) == SCX_EXIT_NONE);

		ret = 0;

		goto err_disable_unlock_all;

	}



	/*

	 * We're fully committed and can't fail. The PREPPED -> ENABLED

	 * transitions here are synchronized against sched_ext_free() through
@@ -5221,7 +5202,11 @@ static int scx_ops_enable(struct sched_ext_ops *ops, struct bpf_link *link) 
	cpus_read_unlock();

	percpu_up_write(&scx_fork_rwsem);



	/* see above ENABLING transition for the explanation on exiting with 0 */

	/*

	 * Returning an error code here would lose the recorded error

	 * information. Exit indicating success so that the error is notified

	 * through ops.exit() with all the details.

	 */

	if (!scx_ops_tryset_enable_state(SCX_OPS_ENABLED, SCX_OPS_ENABLING)) {

		WARN_ON_ONCE(atomic_read(&scx_exit_kind) == SCX_EXIT_NONE);

		ret = 0;