scftorture: Count single_rpc offline failures in statistics outputgrafted

scf_torture_stats_print() aggregates each invoker thread's counters
into a local scf_statistics structure before printing, but the
n_single_rpc_ofl field is missing from the aggregation loop.  As a
result, the "single_rpc_ofl" value printed in the statistics line is
always zero, even when smp_call_function_single() invocations for the
RPC test have failed due to offline CPUs and been counted by the
invoker threads.

Add the missing accumulation so that the printed value reflects the
actual counts.

Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

1 files changed, 141 insertions, 0 deletions

diff --git a/drivers/accessibility/speakup/selection.c b/drivers/accessibility/speakup/selection.c
new file mode 100644
index 000000000..7df7afad5
--- /dev/null
+++ b/drivers/accessibility/speakup/selection.c
@@ -0,0 +1,141 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/slab.h> /* for kmalloc */
+#include <linux/consolemap.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/device.h> /* for dev_warn */
+#include <linux/selection.h>
+#include <linux/workqueue.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/atomic.h>
+#include <linux/console.h>
+
+#include "speakup.h"
+
+unsigned short spk_xs, spk_ys, spk_xe, spk_ye; /* our region points */
+struct vc_data *spk_sel_cons;
+
+struct speakup_selection_work {
+	struct work_struct work;
+	struct tiocl_selection sel;
+	struct tty_struct *tty;
+};
+
+static void __speakup_set_selection(struct work_struct *work)
+{
+	struct speakup_selection_work *ssw =
+		container_of(work, struct speakup_selection_work, work);
+
+	struct tty_struct *tty;
+	struct tiocl_selection sel;
+
+	sel = ssw->sel;
+
+	/* this ensures we copy sel before releasing the lock below */
+	rmb();
+
+	/* release the lock by setting tty of the struct to NULL */
+	tty = xchg(&ssw->tty, NULL);
+
+	if (spk_sel_cons != vc_cons[fg_console].d) {
+		spk_sel_cons = vc_cons[fg_console].d;
+		pr_warn("Selection: mark console not the same as cut\n");
+		goto unref;
+	}
+
+	console_lock();
+	clear_selection();
+	console_unlock();
+
+	set_selection_kernel(&sel, tty);
+
+unref:
+	tty_kref_put(tty);
+}
+
+static struct speakup_selection_work speakup_sel_work = {
+	.work = __WORK_INITIALIZER(speakup_sel_work.work,
+				   __speakup_set_selection)
+};
+
+int speakup_set_selection(struct tty_struct *tty)
+{
+	/* we get kref here first in order to avoid a subtle race when
+	 * cancelling selection work. getting kref first establishes the
+	 * invariant that if speakup_sel_work.tty is not NULL when
+	 * speakup_cancel_selection() is called, it must be the case that a put
+	 * kref is pending.
+	 */
+	tty_kref_get(tty);
+	if (cmpxchg(&speakup_sel_work.tty, NULL, tty)) {
+		tty_kref_put(tty);
+		return -EBUSY;
+	}
+	/* now we have the 'lock' by setting tty member of
+	 * speakup_selection_work. wmb() ensures that writes to
+	 * speakup_sel_work don't happen before cmpxchg() above.
+	 */
+	wmb();
+
+	speakup_sel_work.sel.xs = spk_xs + 1;
+	speakup_sel_work.sel.ys = spk_ys + 1;
+	speakup_sel_work.sel.xe = spk_xe + 1;
+	speakup_sel_work.sel.ye = spk_ye + 1;
+	speakup_sel_work.sel.sel_mode = TIOCL_SELCHAR;
+
+	schedule_work_on(WORK_CPU_UNBOUND, &speakup_sel_work.work);
+
+	return 0;
+}
+
+void speakup_cancel_selection(void)
+{
+	struct tty_struct *tty;
+
+	cancel_work_sync(&speakup_sel_work.work);
+	/* setting to null so that if work fails to run and we cancel it,
+	 * we can run it again without getting EBUSY forever from there on.
+	 * we need to use xchg here to avoid race with speakup_set_selection()
+	 */
+	tty = xchg(&speakup_sel_work.tty, NULL);
+	if (tty)
+		tty_kref_put(tty);
+}
+
+static void __speakup_paste_selection(struct work_struct *work)
+{
+	struct speakup_selection_work *ssw =
+		container_of(work, struct speakup_selection_work, work);
+	struct tty_struct *tty = xchg(&ssw->tty, NULL);
+
+	paste_selection(tty);
+	tty_kref_put(tty);
+}
+
+static struct speakup_selection_work speakup_paste_work = {
+	.work = __WORK_INITIALIZER(speakup_paste_work.work,
+				   __speakup_paste_selection)
+};
+
+int speakup_paste_selection(struct tty_struct *tty)
+{
+	tty_kref_get(tty);
+	if (cmpxchg(&speakup_paste_work.tty, NULL, tty)) {
+		tty_kref_put(tty);
+		return -EBUSY;
+	}
+
+	schedule_work_on(WORK_CPU_UNBOUND, &speakup_paste_work.work);
+	return 0;
+}
+
+void speakup_cancel_paste(void)
+{
+	struct tty_struct *tty;
+
+	cancel_work_sync(&speakup_paste_work.work);
+	tty = xchg(&speakup_paste_work.tty, NULL);
+	if (tty)
+		tty_kref_put(tty);
+}