Commit b983b271 authored by Dimitri Sivanich's avatar Dimitri Sivanich Committed by Linus Torvalds
Browse files

misc: sgi-gru: Don't disable preemption in GRU driver 



Disabling preemption in the GRU driver is unnecessary, and clashes with
sleeping locks in several code paths.  Remove preempt_disable and
preempt_enable from the GRU driver.

Signed-off-by: default avatarDimitri Sivanich <sivanich@hpe.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent ff9d4099

drivers/misc/sgi-gru/grukservices.c

+0 −2
Original line number Diff line number Diff line
@@ -258,7 +258,6 @@ static int gru_get_cpu_resources(int dsr_bytes, void **cb, void **dsr) 
	int lcpu;



	BUG_ON(dsr_bytes > GRU_NUM_KERNEL_DSR_BYTES);

	preempt_disable();

	bs = gru_lock_kernel_context(-1);

	lcpu = uv_blade_processor_id();

	*cb = bs->kernel_cb + lcpu * GRU_HANDLE_STRIDE;
@@ -272,7 +271,6 @@ static int gru_get_cpu_resources(int dsr_bytes, void **cb, void **dsr) 
static void gru_free_cpu_resources(void *cb, void *dsr)

{

	gru_unlock_kernel_context(uv_numa_blade_id());

	preempt_enable();

}



/*

drivers/misc/sgi-gru/grumain.c

+0 −4
Original line number Diff line number Diff line
@@ -937,10 +937,8 @@ vm_fault_t gru_fault(struct vm_fault *vmf) 


again:

	mutex_lock(&gts->ts_ctxlock);

	preempt_disable();



	if (gru_check_context_placement(gts)) {

		preempt_enable();

		mutex_unlock(&gts->ts_ctxlock);

		gru_unload_context(gts, 1);

		return VM_FAULT_NOPAGE;
@@ -949,7 +947,6 @@ vm_fault_t gru_fault(struct vm_fault *vmf) 
	if (!gts->ts_gru) {

		STAT(load_user_context);

		if (!gru_assign_gru_context(gts)) {

			preempt_enable();

			mutex_unlock(&gts->ts_ctxlock);

			set_current_state(TASK_INTERRUPTIBLE);

			schedule_timeout(GRU_ASSIGN_DELAY);  /* true hack ZZZ */
@@ -965,7 +962,6 @@ vm_fault_t gru_fault(struct vm_fault *vmf) 
				vma->vm_page_prot);

	}



	preempt_enable();

	mutex_unlock(&gts->ts_ctxlock);



	return VM_FAULT_NOPAGE;

drivers/misc/sgi-gru/grutlbpurge.c

+0 −2
Original line number Diff line number Diff line
@@ -65,7 +65,6 @@ static struct gru_tlb_global_handle *get_lock_tgh_handle(struct gru_state 
	struct gru_tlb_global_handle *tgh;

	int n;



	preempt_disable();

	if (uv_numa_blade_id() == gru->gs_blade_id)

		n = get_on_blade_tgh(gru);

	else
@@ -79,7 +78,6 @@ static struct gru_tlb_global_handle *get_lock_tgh_handle(struct gru_state 
static void get_unlock_tgh_handle(struct gru_tlb_global_handle *tgh)

{

	unlock_tgh_handle(tgh);

	preempt_enable();

}



/*