[POWERPC] spufs: Add stat file to spufs

Export per-context statistics in spufs.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 51 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/cell/spufs/spufs.h b/arch/powerpc/platforms/cell/spufs/spufs.h
index 7f5d0b2fdea3..cd2b54f6e378 100644
--- a/arch/powerpc/platforms/cell/spufs/spufs.h
+++ b/arch/powerpc/platforms/cell/spufs/spufs.h
@@ -40,6 +40,19 @@ enum {
 struct spu_context_ops;
 struct spu_gang;
 
+/*
+ * This is the state for spu utilization reporting to userspace.
+ * Because this state is visible to userspace it must never change and needs
+ * to be kept strictly separate from any internal state kept by the kernel.
+ */
+enum spuctx_execution_state {
+        SPUCTX_UTIL_USER = 0,
+        SPUCTX_UTIL_SYSTEM,
+        SPUCTX_UTIL_IOWAIT,
+        SPUCTX_UTIL_LOADED,
+        SPUCTX_UTIL_MAX
+};
+
 struct spu_context {
         struct spu *spu;                  /* pointer to a physical SPU */
         struct spu_state csa;             /* SPU context save area. */
@@ -87,6 +100,24 @@ struct spu_context {
         cpumask_t cpus_allowed;
         int policy;
         int prio;
+
+        /* statistics */
+        struct {
+                /* updates protected by ctx->state_mutex */
+                enum spuctx_execution_state execution_state;
+                unsigned long tstamp;           /* time of last ctx switch */
+                unsigned long times[SPUCTX_UTIL_MAX];
+                unsigned long long vol_ctx_switch;
+                unsigned long long invol_ctx_switch;
+                unsigned long long min_flt;
+                unsigned long long maj_flt;
+                unsigned long long hash_flt;
+                unsigned long long slb_flt;
+                unsigned long long slb_flt_base; /* # at last ctx switch */
+                unsigned long long class2_intr;
+                unsigned long long class2_intr_base; /* # at last ctx switch */
+                unsigned long long libassist;
+        } stats;
 };
 
 struct spu_gang {
@@ -256,4 +287,24 @@ struct spufs_coredump_reader {
 extern struct spufs_coredump_reader spufs_coredump_read[];
 extern int spufs_coredump_num_notes;
 
+/*
+ * This function is a little bit too large for an inline, but
+ * as fault.c is built into the kernel we can't move it out of
+ * line.
+ */
+static inline void spuctx_switch_state(struct spu_context *ctx,
+                enum spuctx_execution_state new_state)
+{
+        WARN_ON(!mutex_is_locked(&ctx->state_mutex));
+
+        if (ctx->stats.execution_state != new_state) {
+                unsigned long curtime = jiffies;
+
+                ctx->stats.times[ctx->stats.execution_state] +=
+                                 curtime - ctx->stats.tstamp;
+                ctx->stats.tstamp = curtime;
+                ctx->stats.execution_state = new_state;
+        }
+}
+
 #endif