cpumask: factor out show_cpumap into separate helper function

Many sysfs *_show function use cpu{list,mask}_scnprintf to copy cpumap
to the buffer aligned to PAGE_SIZE, append '\n' and '\0' to return null
terminated buffer with newline.

This patch creates a new helper function cpumap_print_to_pagebuf in
cpumask.h using newly added bitmap_print_to_pagebuf and consolidates
most of those sysfs functions using the new helper function.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Suggested-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: x86@kernel.org
Cc: linux-acpi@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

12 files changed, 73 insertions, 87 deletions

diff --git a/arch/x86/kernel/cpu/perf_event_amd_iommu.c b/arch/x86/kernel/cpu/perf_event_amd_iommu.c
index 639d1289b1ba..97242a9242bd 100644
--- a/arch/x86/kernel/cpu/perf_event_amd_iommu.c
+++ b/arch/x86/kernel/cpu/perf_event_amd_iommu.c
@@ -130,10 +130,7 @@ static ssize_t _iommu_cpumask_show(struct device *dev,
                                    struct device_attribute *attr,
                                    char *buf)
 {
-        int n = cpulist_scnprintf(buf, PAGE_SIZE - 2, &iommu_cpumask);
-        buf[n++] = '\n';
-        buf[n] = '\0';
-        return n;
+        return cpumap_print_to_pagebuf(true, buf, &iommu_cpumask);
 }
 static DEVICE_ATTR(cpumask, S_IRUGO, _iommu_cpumask_show, NULL);
 
diff --git a/arch/x86/kernel/cpu/perf_event_amd_uncore.c b/arch/x86/kernel/cpu/perf_event_amd_uncore.c
index 30790d798e6b..cc6cedb8f25d 100644
--- a/arch/x86/kernel/cpu/perf_event_amd_uncore.c
+++ b/arch/x86/kernel/cpu/perf_event_amd_uncore.c
@@ -219,7 +219,6 @@ static ssize_t amd_uncore_attr_show_cpumask(struct device *dev,
                                             struct device_attribute *attr,
                                             char *buf)
 {
-        int n;
         cpumask_t *active_mask;
         struct pmu *pmu = dev_get_drvdata(dev);
 
@@ -230,10 +229,7 @@ static ssize_t amd_uncore_attr_show_cpumask(struct device *dev,
         else
                 return 0;
 
-        n = cpulist_scnprintf(buf, PAGE_SIZE - 2, active_mask);
-        buf[n++] = '\n';
-        buf[n] = '\0';
-        return n;
+        return cpumap_print_to_pagebuf(true, buf, active_mask);
 }
 static DEVICE_ATTR(cpumask, S_IRUGO, amd_uncore_attr_show_cpumask, NULL);
 
diff --git a/arch/x86/kernel/cpu/perf_event_intel_rapl.c b/arch/x86/kernel/cpu/perf_event_intel_rapl.c
index d64f275fe274..673f930c700f 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_rapl.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_rapl.c
@@ -365,11 +365,7 @@ static void rapl_pmu_event_read(struct perf_event *event)
 static ssize_t rapl_get_attr_cpumask(struct device *dev,
                                 struct device_attribute *attr, char *buf)
 {
-        int n = cpulist_scnprintf(buf, PAGE_SIZE - 2, &rapl_cpu_mask);
-
-        buf[n++] = '\n';
-        buf[n] = '\0';
-        return n;
+        return cpumap_print_to_pagebuf(true, buf, &rapl_cpu_mask);
 }
 
 static DEVICE_ATTR(cpumask, S_IRUGO, rapl_get_attr_cpumask, NULL);
diff --git a/arch/x86/kernel/cpu/perf_event_intel_uncore.c b/arch/x86/kernel/cpu/perf_event_intel_uncore.c
index 9762dbd9f3f7..08f3fed2b0f2 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_uncore.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_uncore.c
@@ -647,11 +647,7 @@ static int uncore_pmu_event_init(struct perf_event *event)
 static ssize_t uncore_get_attr_cpumask(struct device *dev,
                                 struct device_attribute *attr, char *buf)
 {
-        int n = cpulist_scnprintf(buf, PAGE_SIZE - 2, &uncore_cpu_mask);
-
-        buf[n++] = '\n';
-        buf[n] = '\0';
-        return n;
+        return cpumap_print_to_pagebuf(true, buf, &uncore_cpu_mask);
 }
 
 static DEVICE_ATTR(cpumask, S_IRUGO, uncore_get_attr_cpumask, NULL);
diff --git a/drivers/acpi/acpi_pad.c b/drivers/acpi/acpi_pad.c
index f148a0580e04..c7b105c0e1d3 100644
--- a/drivers/acpi/acpi_pad.c
+++ b/drivers/acpi/acpi_pad.c
@@ -350,12 +350,10 @@ static ssize_t acpi_pad_idlecpus_store(struct device *dev,
 static ssize_t acpi_pad_idlecpus_show(struct device *dev,
         struct device_attribute *attr, char *buf)
 {
-        int n = 0;
-        n = cpumask_scnprintf(buf, PAGE_SIZE-2, to_cpumask(pad_busy_cpus_bits));
-        buf[n++] = '\n';
-        buf[n] = '\0';
-        return n;
+        return cpumap_print_to_pagebuf(false, buf,
+                                       to_cpumask(pad_busy_cpus_bits));
 }
+
 static DEVICE_ATTR(idlecpus, S_IRUGO|S_IWUSR,
         acpi_pad_idlecpus_show,
         acpi_pad_idlecpus_store);
diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index 006b1bc5297d..4d8a56406fbb 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -207,11 +207,8 @@ static ssize_t show_cpus_attr(struct device *dev,
                               char *buf)
 {
         struct cpu_attr *ca = container_of(attr, struct cpu_attr, attr);
-        int n = cpulist_scnprintf(buf, PAGE_SIZE-2, *(ca->map));
 
-        buf[n++] = '\n';
-        buf[n] = '\0';
-        return n;
+        return cpumap_print_to_pagebuf(true, buf, *ca->map);
 }
 
 #define _CPU_ATTR(name, map) \
diff --git a/drivers/base/node.c b/drivers/base/node.c
index 472168cd0c97..a3b82e9c7f20 100644
--- a/drivers/base/node.c
+++ b/drivers/base/node.c
@@ -25,32 +25,26 @@ static struct bus_type node_subsys = {
 };
 
 
-static ssize_t node_read_cpumap(struct device *dev, int type, char *buf)
+static ssize_t node_read_cpumap(struct device *dev, bool list, char *buf)
 {
         struct node *node_dev = to_node(dev);
         const struct cpumask *mask = cpumask_of_node(node_dev->dev.id);
-        int len;
 
         /* 2008/04/07: buf currently PAGE_SIZE, need 9 chars per 32 bits. */
         BUILD_BUG_ON((NR_CPUS/32 * 9) > (PAGE_SIZE-1));
 
-        len = type?
-                cpulist_scnprintf(buf, PAGE_SIZE-2, mask) :
-                cpumask_scnprintf(buf, PAGE_SIZE-2, mask);
-        buf[len++] = '\n';
-        buf[len] = '\0';
-        return len;
+        return cpumap_print_to_pagebuf(list, buf, mask);
 }
 
 static inline ssize_t node_read_cpumask(struct device *dev,
                                 struct device_attribute *attr, char *buf)
 {
-        return node_read_cpumap(dev, 0, buf);
+        return node_read_cpumap(dev, false, buf);
 }
 static inline ssize_t node_read_cpulist(struct device *dev,
                                 struct device_attribute *attr, char *buf)
 {
-        return node_read_cpumap(dev, 1, buf);
+        return node_read_cpumap(dev, true, buf);
 }
 
 static DEVICE_ATTR(cpumap,  S_IRUGO, node_read_cpumask, NULL);
diff --git a/drivers/base/topology.c b/drivers/base/topology.c
index be7c1fb7c0c9..f7c353843ddf 100644
--- a/drivers/base/topology.c
+++ b/drivers/base/topology.c
@@ -42,29 +42,11 @@ static ssize_t show_##name(struct device *dev,			\
         return sprintf(buf, "%d\n", topology_##name(dev->id));  \
 }