sh: oprofile: Fix up and extend op_name_from_perf_id().

op_name_from_perf_id() currently returns a local variable, which isn't
terribly productive. As we only handle a single PMU case for now, simply
allocate and free the string from the arch init/exit context and have
op_name_from_perf_id() hand back the cached string.

This also takes UTS_MACHINE in to account, given that we build for
multiple architectures.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

4 files changed, 21 insertions, 16 deletions

diff --git a/arch/sh/kernel/cpu/sh4/perf_event.c b/arch/sh/kernel/cpu/sh4/perf_event.c
index 7f9ecc9c2d02..dbf3b4bb71fe 100644
--- a/arch/sh/kernel/cpu/sh4/perf_event.c
+++ b/arch/sh/kernel/cpu/sh4/perf_event.c
@@ -225,7 +225,7 @@ static void sh7750_pmu_enable_all(void)
 }
 
 static struct sh_pmu sh7750_pmu = {
-        .name           = "SH7750",
+        .name           = "sh7750",
         .num_events     = 2,
         .event_map      = sh7750_event_map,
         .max_events     = ARRAY_SIZE(sh7750_general_events),
diff --git a/arch/sh/kernel/cpu/sh4a/perf_event.c b/arch/sh/kernel/cpu/sh4a/perf_event.c
index b8b873d8d6b5..580276525731 100644
--- a/arch/sh/kernel/cpu/sh4a/perf_event.c
+++ b/arch/sh/kernel/cpu/sh4a/perf_event.c
@@ -259,7 +259,7 @@ static void sh4a_pmu_enable_all(void)
 }
 
 static struct sh_pmu sh4a_pmu = {
-        .name           = "SH-4A",
+        .name           = "sh4a",
         .num_events     = 2,
         .event_map      = sh4a_event_map,
         .max_events     = ARRAY_SIZE(sh4a_general_events),
diff --git a/arch/sh/oprofile/Makefile b/arch/sh/oprofile/Makefile
index e85aae73e3dc..ce3b119021e7 100644
--- a/arch/sh/oprofile/Makefile
+++ b/arch/sh/oprofile/Makefile
@@ -1,5 +1,7 @@
 obj-$(CONFIG_OPROFILE) += oprofile.o
 
+CFLAGS_common.o += -DUTS_MACHINE='"$(UTS_MACHINE)"'
+
 DRIVER_OBJS = $(addprefix ../../../drivers/oprofile/, \
                 oprof.o cpu_buffer.o buffer_sync.o \
                 event_buffer.o oprofile_files.o \
diff --git a/arch/sh/oprofile/common.c b/arch/sh/oprofile/common.c
index e10d89376f9b..84533142da9b 100644
--- a/arch/sh/oprofile/common.c
+++ b/arch/sh/oprofile/common.c
@@ -1,7 +1,7 @@
 /*
  * arch/sh/oprofile/init.c
  *
- * Copyright (C) 2003 - 2008  Paul Mundt
+ * Copyright (C) 2003 - 2010  Paul Mundt
  *
  * Based on arch/mips/oprofile/common.c:
  *
@@ -18,38 +18,41 @@
 #include <linux/errno.h>
 #include <linux/smp.h>
 #include <linux/perf_event.h>
+#include <linux/slab.h>
 #include <asm/processor.h>
 
 #ifdef CONFIG_HW_PERF_EVENTS
 extern void sh_backtrace(struct pt_regs * const regs, unsigned int depth);
 
+/*
+ * This will need to be reworked when multiple PMUs are supported.
+ */
+static char *sh_pmu_op_name;
+
 char *op_name_from_perf_id(void)
 {
-        const char *pmu;
-        char buf[20];
-        int size;
-
-        pmu = perf_pmu_name();
-        if (!pmu)
-                return NULL;
-
-        size = snprintf(buf, sizeof(buf), "sh/%s", pmu);
-        if (size > -1 && size < sizeof(buf))
-                return buf;
-
-        return NULL;
+        return sh_pmu_op_name;
 }
 
 int __init oprofile_arch_init(struct oprofile_operations *ops)
 {
         ops->backtrace = sh_backtrace;
 
+        if (perf_num_counters() == 0)
+                return -ENODEV;
+
+        sh_pmu_op_name = kasprintf(GFP_KERNEL, "%s/%s",
+                                   UTS_MACHINE, perf_pmu_name());
+        if (unlikely(!sh_pmu_op_name))
+                return -ENOMEM;
+
         return oprofile_perf_init(ops);
 }
 
 void __exit oprofile_arch_exit(void)
 {
         oprofile_perf_exit();
+        kfree(sh_pmu_op_name);
 }
 #else
 int __init oprofile_arch_init(struct oprofile_operations *ops)