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>

3 files changed, 259 insertions, 0 deletions

diff --git a/lib/raid/raid6/s390/pq_arch.h b/lib/raid/raid6/s390/pq_arch.h
new file mode 100644
index 000000000..95d14c342
--- /dev/null
+++ b/lib/raid/raid6/s390/pq_arch.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include <linux/cpufeature.h>
+
+extern const struct raid6_calls raid6_s390vx8;
+extern const struct raid6_recov_calls raid6_recov_s390xc;
+
+static __always_inline void __init arch_raid6_init(void)
+{
+	if (cpu_has_vx())
+		raid6_algo_add(&raid6_s390vx8);
+	else
+		raid6_algo_add_default();
+	raid6_recov_algo_add(&raid6_recov_s390xc);
+}
diff --git a/lib/raid/raid6/s390/recov_s390xc.c b/lib/raid/raid6/s390/recov_s390xc.c
new file mode 100644
index 000000000..08d56896e
--- /dev/null
+++ b/lib/raid/raid6/s390/recov_s390xc.c
@@ -0,0 +1,116 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * RAID-6 data recovery in dual failure mode based on the XC instruction.
+ *
+ * Copyright IBM Corp. 2016
+ * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
+ */
+
+#include <linux/mm.h>
+#include <linux/raid/pq.h>
+#include "algos.h"
+
+static inline void xor_block(u8 *p1, u8 *p2)
+{
+	typedef struct { u8 _[256]; } addrtype;
+
+	asm volatile(
+		"	xc	0(256,%[p1]),0(%[p2])\n"
+		: "+m" (*(addrtype *) p1) : "m" (*(addrtype *) p2),
+		  [p1] "a" (p1), [p2] "a" (p2) : "cc");
+}
+
+/* Recover two failed data blocks. */
+static void raid6_2data_recov_s390xc(int disks, size_t bytes, int faila,
+		int failb, void **ptrs)
+{
+	u8 *p, *q, *dp, *dq;
+	const u8 *pbmul;	/* P multiplier table for B data */
+	const u8 *qmul;		/* Q multiplier table (for both) */
+	int i;
+
+	p = (u8 *)ptrs[disks-2];
+	q = (u8 *)ptrs[disks-1];
+
+	/* Compute syndrome with zero for the missing data pages
+	   Use the dead data pages as temporary storage for
+	   delta p and delta q */
+	dp = (u8 *)ptrs[faila];
+	ptrs[faila] = page_address(ZERO_PAGE(0));
+	ptrs[disks-2] = dp;
+	dq = (u8 *)ptrs[failb];
+	ptrs[failb] = page_address(ZERO_PAGE(0));
+	ptrs[disks-1] = dq;
+
+	raid6_gen_syndrome(disks, bytes, ptrs);
+
+	/* Restore pointer table */
+	ptrs[faila]   = dp;
+	ptrs[failb]   = dq;
+	ptrs[disks-2] = p;
+	ptrs[disks-1] = q;
+
+	/* Now, pick the proper data tables */
+	pbmul = raid6_gfmul[raid6_gfexi[failb-faila]];
+	qmul  = raid6_gfmul[raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]]];
+
+	/* Now do it... */
+	while (bytes) {
+		xor_block(dp, p);
+		xor_block(dq, q);
+		for (i = 0; i < 256; i++)
+			dq[i] = pbmul[dp[i]] ^ qmul[dq[i]];
+		xor_block(dp, dq);
+		p += 256;
+		q += 256;
+		dp += 256;
+		dq += 256;
+		bytes -= 256;
+	}
+}
+
+/* Recover failure of one data block plus the P block */
+static void raid6_datap_recov_s390xc(int disks, size_t bytes, int faila,
+		void **ptrs)
+{
+	u8 *p, *q, *dq;
+	const u8 *qmul;		/* Q multiplier table */
+	int i;
+
+	p = (u8 *)ptrs[disks-2];
+	q = (u8 *)ptrs[disks-1];
+
+	/* Compute syndrome with zero for the missing data page
+	   Use the dead data page as temporary storage for delta q */
+	dq = (u8 *)ptrs[faila];
+	ptrs[faila] = page_address(ZERO_PAGE(0));
+	ptrs[disks-1] = dq;
+
+	raid6_gen_syndrome(disks, bytes, ptrs);
+
+	/* Restore pointer table */
+	ptrs[faila]   = dq;
+	ptrs[disks-1] = q;
+
+	/* Now, pick the proper data tables */
+	qmul  = raid6_gfmul[raid6_gfinv[raid6_gfexp[faila]]];
+
+	/* Now do it... */
+	while (bytes) {
+		xor_block(dq, q);
+		for (i = 0; i < 256; i++)
+			dq[i] = qmul[dq[i]];
+		xor_block(p, dq);
+		p += 256;
+		q += 256;
+		dq += 256;
+		bytes -= 256;
+	}
+}
+
+
+const struct raid6_recov_calls raid6_recov_s390xc = {
+	.data2 = raid6_2data_recov_s390xc,
+	.datap = raid6_datap_recov_s390xc,
+	.name = "s390xc",
+};
diff --git a/lib/raid/raid6/s390/s390vx.uc b/lib/raid/raid6/s390/s390vx.uc
new file mode 100644
index 000000000..e5cf9054b
--- /dev/null
+++ b/lib/raid/raid6/s390/s390vx.uc
@@ -0,0 +1,128 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * raid6_vx$#.c
+ *
+ * $#-way unrolled RAID6 gen/xor functions for s390
+ * based on the vector facility
+ *
+ * Copyright IBM Corp. 2016
+ * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
+ *
+ * This file is postprocessed using unroll.awk.
+ */
+
+#include <linux/cpufeature.h>
+#include <asm/fpu.h>
+#include "algos.h"
+
+#define NSIZE 16
+
+static __always_inline void LOAD_CONST(void)
+{
+	fpu_vrepib(24, 0x07);
+	fpu_vrepib(25, 0x1d);
+}
+
+/*
+ * The SHLBYTE() operation shifts each of the 16 bytes in
+ * vector register y left by 1 bit and stores the result in
+ * vector register x.
+ */
+#define SHLBYTE(x, y)		fpu_vab(x, y, y)
+
+/*
+ * For each of the 16 bytes in the vector register y the MASK()
+ * operation returns 0xFF if the high bit of the byte is 1,
+ * or 0x00 if the high bit is 0. The result is stored in vector
+ * register x.
+ */
+#define MASK(x, y)		fpu_vesravb(x, y, 24)
+
+#define AND(x, y, z)		fpu_vn(x, y, z)
+#define XOR(x, y, z)		fpu_vx(x, y, z)
+#define LOAD_DATA(x, ptr)	fpu_vlm(x, x + $# - 1, ptr)
+#define STORE_DATA(x, ptr)	fpu_vstm(x, x + $# - 1, ptr)
+#define COPY_VEC(x, y)		fpu_vlr(x, y)
+
+static void raid6_s390vx$#_gen_syndrome(int disks, size_t bytes, void **ptrs)
+{
+	DECLARE_KERNEL_FPU_ONSTACK32(vxstate);
+	u8 **dptr, *p, *q;
+	int d, z, z0;
+
+	kernel_fpu_begin(&vxstate, KERNEL_VXR);
+	LOAD_CONST();
+
+	dptr = (u8 **) ptrs;
+	z0 = disks - 3;		/* Highest data disk */
+	p = dptr[z0 + 1];	/* XOR parity */
+	q = dptr[z0 + 2];	/* RS syndrome */
+
+	for (d = 0; d < bytes; d += $#*NSIZE) {
+		LOAD_DATA(0,&dptr[z0][d]);
+		COPY_VEC(8+$$,0+$$);
+		for (z = z0 - 1; z >= 0; z--) {
+			MASK(16+$$,8+$$);
+			AND(16+$$,16+$$,25);
+			SHLBYTE(8+$$,8+$$);
+			XOR(8+$$,8+$$,16+$$);
+			LOAD_DATA(16,&dptr[z][d]);
+			XOR(0+$$,0+$$,16+$$);
+			XOR(8+$$,8+$$,16+$$);
+		}
+		STORE_DATA(0,&p[d]);
+		STORE_DATA(8,&q[d]);
+	}
+	kernel_fpu_end(&vxstate, KERNEL_VXR);
+}
+
+static void raid6_s390vx$#_xor_syndrome(int disks, int start, int stop,
+					size_t bytes, void **ptrs)
+{
+	DECLARE_KERNEL_FPU_ONSTACK32(vxstate);
+	u8 **dptr, *p, *q;
+	int d, z, z0;
+
+	dptr = (u8 **) ptrs;
+	z0 = stop;		/* P/Q right side optimization */
+	p = dptr[disks - 2];	/* XOR parity */
+	q = dptr[disks - 1];	/* RS syndrome */
+
+	kernel_fpu_begin(&vxstate, KERNEL_VXR);
+	LOAD_CONST();
+
+	for (d = 0; d < bytes; d += $#*NSIZE) {
+		/* P/Q data pages */
+		LOAD_DATA(0,&dptr[z0][d]);
+		COPY_VEC(8+$$,0+$$);
+		for (z = z0 - 1; z >= start; z--) {
+			MASK(16+$$,8+$$);
+			AND(16+$$,16+$$,25);
+			SHLBYTE(8+$$,8+$$);
+			XOR(8+$$,8+$$,16+$$);
+			LOAD_DATA(16,&dptr[z][d]);
+			XOR(0+$$,0+$$,16+$$);
+			XOR(8+$$,8+$$,16+$$);
+		}
+		/* P/Q left side optimization */
+		for (z = start - 1; z >= 0; z--) {
+			MASK(16+$$,8+$$);
+			AND(16+$$,16+$$,25);
+			SHLBYTE(8+$$,8+$$);
+			XOR(8+$$,8+$$,16+$$);
+		}
+		LOAD_DATA(16,&p[d]);
+		XOR(16+$$,16+$$,0+$$);
+		STORE_DATA(16,&p[d]);
+		LOAD_DATA(16,&q[d]);
+		XOR(16+$$,16+$$,8+$$);
+		STORE_DATA(16,&q[d]);
+	}
+	kernel_fpu_end(&vxstate, KERNEL_VXR);
+}
+
+const struct raid6_calls raid6_s390vx$# = {
+	.gen_syndrome	= raid6_s390vx$#_gen_syndrome,
+	.xor_syndrome	= raid6_s390vx$#_xor_syndrome,
+	.name		= "vx128x$#",
+};