[PATCH v2 4/6] powerpc/perf: Add event attribute and group to IMA pmus

From: Hemant Kumar
Date: Mon Nov 21 2016 - 01:11:10 EST


Device tree IMA driver code parses the IMA units and their events. It
passes the information to IMA pmu code which is placed in powerpc/perf
as "ima-pmu.c".

This patch creates only event attributes and attribute groups for the
IMA pmus.

Cc: Madhavan Srinivasan <maddy@xxxxxxxxxxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Anton Blanchard <anton@xxxxxxxxx>
Cc: Sukadev Bhattiprolu <sukadev@xxxxxxxxxxxxxxxxxx>
Cc: Michael Neuling <mikey@xxxxxxxxxxx>
Cc: Stewart Smith <stewart@xxxxxxxxxxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Signed-off-by: Hemant Kumar <hemant@xxxxxxxxxxxxxxxxxx>
---
Changelog:
v1 -> v2:
- Changes to Makefile to only enable this feature for
CONFIG_PPC_POWERNV=y

arch/powerpc/perf/Makefile | 6 +-
arch/powerpc/perf/ima-pmu.c | 96 +++++++++++++++++++++++++++++++
arch/powerpc/platforms/powernv/opal-ima.c | 12 +++-
3 files changed, 111 insertions(+), 3 deletions(-)
create mode 100644 arch/powerpc/perf/ima-pmu.c

diff --git a/arch/powerpc/perf/Makefile b/arch/powerpc/perf/Makefile
index f102d53..099c61a 100644
--- a/arch/powerpc/perf/Makefile
+++ b/arch/powerpc/perf/Makefile
@@ -2,10 +2,14 @@ subdir-ccflags-$(CONFIG_PPC_WERROR) := -Werror

obj-$(CONFIG_PERF_EVENTS) += callchain.o perf_regs.o

+ima-$(CONFIG_PPC_POWERNV) += ima-pmu.o
+
obj-$(CONFIG_PPC_PERF_CTRS) += core-book3s.o bhrb.o
obj64-$(CONFIG_PPC_PERF_CTRS) += power4-pmu.o ppc970-pmu.o power5-pmu.o \
power5+-pmu.o power6-pmu.o power7-pmu.o \
- isa207-common.o power8-pmu.o power9-pmu.o
+ isa207-common.o power8-pmu.o power9-pmu.o \
+ $(ima-y)
+
obj32-$(CONFIG_PPC_PERF_CTRS) += mpc7450-pmu.o

obj-$(CONFIG_FSL_EMB_PERF_EVENT) += core-fsl-emb.o
diff --git a/arch/powerpc/perf/ima-pmu.c b/arch/powerpc/perf/ima-pmu.c
new file mode 100644
index 0000000..50d2226
--- /dev/null
+++ b/arch/powerpc/perf/ima-pmu.c
@@ -0,0 +1,96 @@
+/*
+ * Nest Performance Monitor counter support.
+ *
+ * Copyright (C) 2016 Madhavan Srinivasan, IBM Corporation.
+ * (C) 2016 Hemant K Shaw, IBM Corporation.
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+#include <linux/perf_event.h>
+#include <linux/slab.h>
+#include <asm/opal.h>
+#include <asm/ima-pmu.h>
+#include <asm/cputhreads.h>
+#include <linux/string.h>
+
+struct perchip_nest_info nest_perchip_info[IMA_MAX_CHIPS];
+struct ima_pmu *per_nest_pmu_arr[IMA_MAX_PMUS];
+
+/* dev_str_attr : Populate event "name" and string "str" in attribute */
+static struct attribute *dev_str_attr(const char *name, const char *str)
+{
+ struct perf_pmu_events_attr *attr;
+
+ attr = kzalloc(sizeof(*attr), GFP_KERNEL);
+
+ sysfs_attr_init(&attr->attr.attr);
+
+ attr->event_str = str;
+ attr->attr.attr.name = name;
+ attr->attr.attr.mode = 0444;
+ attr->attr.show = perf_event_sysfs_show;
+
+ return &attr->attr.attr;
+}
+
+/*
+ * update_events_in_group: Update the "events" information in an attr_group
+ * and assign the attr_group to the pmu "pmu".
+ */
+static int update_events_in_group(struct ima_events *events,
+ int idx, struct ima_pmu *pmu)
+{
+ struct attribute_group *attr_group;
+ struct attribute **attrs;
+ int i;
+
+ /* Allocate memory for attribute group */
+ attr_group = kzalloc(sizeof(*attr_group), GFP_KERNEL);
+ if (!attr_group)
+ return -ENOMEM;
+
+ /* Allocate memory for attributes */
+ attrs = kzalloc((sizeof(struct attribute *) * (idx + 1)), GFP_KERNEL);
+ if (!attrs) {
+ kfree(attr_group);
+ return -ENOMEM;
+ }
+
+ attr_group->name = "events";
+ attr_group->attrs = attrs;
+ for (i = 0; i < idx; i++, events++) {
+ attrs[i] = dev_str_attr((char *)events->ev_name,
+ (char *)events->ev_value);
+ }
+
+ pmu->attr_groups[0] = attr_group;
+ return 0;
+}
+
+/*
+ * init_ima_pmu : Setup the IMA pmu device in "pmu_ptr" and its events
+ * "events".
+ * Setup the cpu mask information for these pmus and setup the state machine
+ * hotplug notifiers as well.
+ */
+int init_ima_pmu(struct ima_events *events, int idx,
+ struct ima_pmu *pmu_ptr)
+{
+ int ret = -ENODEV;
+
+ ret = update_events_in_group(events, idx, pmu_ptr);
+ if (ret)
+ goto err_free;
+
+ return 0;
+
+err_free:
+ /* Only free the attr_groups which are dynamically allocated */
+ if (pmu_ptr->attr_groups[0]) {
+ kfree(pmu_ptr->attr_groups[0]->attrs);
+ kfree(pmu_ptr->attr_groups[0]);
+ }
+
+ return ret;
+}
diff --git a/arch/powerpc/platforms/powernv/opal-ima.c b/arch/powerpc/platforms/powernv/opal-ima.c
index e8d5771..d2e6910 100644
--- a/arch/powerpc/platforms/powernv/opal-ima.c
+++ b/arch/powerpc/platforms/powernv/opal-ima.c
@@ -31,8 +31,11 @@
#include <asm/cputable.h>
#include <asm/ima-pmu.h>

-struct perchip_nest_info nest_perchip_info[IMA_MAX_CHIPS];
-struct ima_pmu *per_nest_pmu_arr[IMA_MAX_PMUS];
+extern struct perchip_nest_info nest_perchip_info[IMA_MAX_CHIPS];
+extern struct ima_pmu *per_nest_pmu_arr[IMA_MAX_PMUS];
+
+extern int init_ima_pmu(struct ima_events *events,
+ int idx, struct ima_pmu *pmu_ptr);

static int ima_event_info(char *name, struct ima_events *events)
{
@@ -335,6 +338,11 @@ static int ima_pmu_create(struct device_node *parent, int pmu_index)
idx += ret;
}

+ ret = init_ima_pmu(events, idx, pmu_ptr);
+ if (ret) {
+ pr_err("IMA PMU %s Register failed\n", pmu_ptr->pmu.name);
+ goto free_events;
+ }
return 0;

free_events:
--
2.7.4