From d6110089c56efd5ec3485bd5edd4929bbd430098 Mon Sep 17 00:00:00 2001
From: stephane eranian <eranian@hpl.hp.com>
Date: Mon, 18 Apr 2005 11:42:00 -0700
Subject: [PATCH] --- yaml --- r: 922 b: refs/heads/master c:
 a5a70b75d93b26e14c0c5e759099d602a480b9e2 h: refs/heads/master v: v3

---
 [refs]                           |  2 +-
 trunk/arch/ia64/kernel/perfmon.c | 30 ++++++++++++++++++++----------
 2 files changed, 21 insertions(+), 11 deletions(-)

diff --git a/[refs] b/[refs]
index 1049522076c6..e590285e38c1 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 8df5a500a3e97f7811cdce0f553ca1917ccd4220
+refs/heads/master: a5a70b75d93b26e14c0c5e759099d602a480b9e2
diff --git a/trunk/arch/ia64/kernel/perfmon.c b/trunk/arch/ia64/kernel/perfmon.c
index fd4f3be6e856..71c101601e3e 100644
--- a/trunk/arch/ia64/kernel/perfmon.c
+++ b/trunk/arch/ia64/kernel/perfmon.c
@@ -4215,7 +4215,7 @@ pfm_context_load(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
 		DPRINT(("cannot load to [%d], invalid ctx_state=%d\n",
 			req->load_pid,
 			ctx->ctx_state));
-		return -EINVAL;
+		return -EBUSY;
 	}
 
 	DPRINT(("load_pid [%d] using_dbreg=%d\n", req->load_pid, ctx->ctx_fl_using_dbreg));
@@ -4717,16 +4717,26 @@ pfm_check_task_state(pfm_context_t *ctx, int cmd, unsigned long flags)
 	if (task == current || ctx->ctx_fl_system) return 0;
 
 	/*
-	 * if context is UNLOADED we are safe to go
-	 */
-	if (state == PFM_CTX_UNLOADED) return 0;
-
-	/*
-	 * no command can operate on a zombie context
+	 * we are monitoring another thread
 	 */
-	if (state == PFM_CTX_ZOMBIE) {
-		DPRINT(("cmd %d state zombie cannot operate on context\n", cmd));
-		return -EINVAL;
+	switch(state) {
+		case PFM_CTX_UNLOADED:
+			/*
+			 * if context is UNLOADED we are safe to go
+			 */
+			return 0;
+		case PFM_CTX_ZOMBIE:
+			/*
+			 * no command can operate on a zombie context
+			 */
+			DPRINT(("cmd %d state zombie cannot operate on context\n", cmd));
+			return -EINVAL;
+		case PFM_CTX_MASKED:
+			/*
+			 * PMU state has been saved to software even though
+			 * the thread may still be running.
+			 */
+			if (cmd != PFM_UNLOAD_CONTEXT) return 0;
 	}
 
 	/*