[PATCH -tip v2 2/2] x86: Issue at least one memory barrier in stop_machine_text_poke().

[PATCH -tip v2 2/2] x86: Issue at least one memory barrier in stop_machine_text_poke().

[Masami Hiramatsu]

Fix stop_machine_text_poke() to issue smp_mb() before exiting waiting
loop, and use cpu_relax() for waiting.

Changes in v2:
 - Don't use ACCESS_ONCE().

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
---

 arch/x86/kernel/alternative.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index 635e4f4..3a4bf35 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -597,8 +597,8 @@ static int __kprobes stop_machine_text_poke(void *data)
 		wrote_text = 1;
 	} else {
 		while (!wrote_text)
-			smp_rmb();
-		sync_core();
+			cpu_relax();
+		smp_mb();	/* Load wrote_text before following execution */
 	}
 
 	flush_icache_range((unsigned long)tpp->addr,


-- 
Masami Hiramatsu
e-mail: mhiramat@redhat.com

[PATCH -tip v2 1/2] perf probe: Correct probe syntax on command line help

[Masami Hiramatsu]

Move @SRC right after FUNC in syntax according to syntax change
on command line help.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
---

 tools/perf/builtin-probe.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
index e3dfd0d..c30a335 100644
--- a/tools/perf/builtin-probe.c
+++ b/tools/perf/builtin-probe.c
@@ -177,7 +177,7 @@ static const struct option options[] = {
 #ifdef NO_DWARF_SUPPORT
 		"[EVENT=]FUNC[+OFF|%return] [ARG ...]",
 #else
-		"[EVENT=]FUNC[+OFF|%return|:RL|;PT][@SRC]|SRC:AL|SRC;PT"
+		"[EVENT=]FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT"
 		" [ARG ...]",
 #endif
 		"probe point definition, where\n"


-- 
Masami Hiramatsu
e-mail: mhiramat@redhat.com

[tip:perf/pebs] x86: Issue at least one memory barrier in stop_machine_text_poke()

[tip-bot for Masami Hiramatsu]

Commit-ID:  e5a11016643d1ab7172193591506d33a844734cc
Gitweb:     http://git.kernel.org/tip/e5a11016643d1ab7172193591506d33a844734cc
Author:     Masami Hiramatsu <mhiramat@redhat.com>
AuthorDate: Wed, 3 Mar 2010 22:38:50 -0500
Committer:  Ingo Molnar <mingo@elte.hu>
CommitDate: Thu, 4 Mar 2010 11:39:21 +0100

x86: Issue at least one memory barrier in stop_machine_text_poke()

Fix stop_machine_text_poke() to issue smp_mb() before exiting
waiting loop, and use cpu_relax() for waiting.

Changes in v2:
 - Don't use ACCESS_ONCE().

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Jason Baron <jbaron@redhat.com>
LKML-Reference: <20100304033850.3819.74590.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 arch/x86/kernel/alternative.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index c41f13c..e0b8770 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -595,8 +595,8 @@ static int __kprobes stop_machine_text_poke(void *data)
 		wrote_text = 1;
 	} else {
 		while (!wrote_text)
-			smp_rmb();
-		sync_core();
+			cpu_relax();
+		smp_mb();	/* Load wrote_text before following execution */
 	}
 
 	flush_icache_range((unsigned long)tpp->addr,

[tip:perf/pebs] perf probe: Correct probe syntax on command line help

[tip-bot for Masami Hiramatsu]

Commit-ID:  32cb0dd50672056e510ccab442dc9c3a03be649e
Gitweb:     http://git.kernel.org/tip/32cb0dd50672056e510ccab442dc9c3a03be649e
Author:     Masami Hiramatsu <mhiramat@redhat.com>
AuthorDate: Wed, 3 Mar 2010 22:38:43 -0500
Committer:  Ingo Molnar <mingo@elte.hu>
CommitDate: Thu, 4 Mar 2010 11:39:21 +0100

perf probe: Correct probe syntax on command line help

Move @SRC right after FUNC in syntax according to syntax change
on command line help.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
LKML-Reference: <20100304033843.3819.10087.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 tools/perf/builtin-probe.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
index e3dfd0d..c30a335 100644
--- a/tools/perf/builtin-probe.c
+++ b/tools/perf/builtin-probe.c
@@ -177,7 +177,7 @@ static const struct option options[] = {
 #ifdef NO_DWARF_SUPPORT
 		"[EVENT=]FUNC[+OFF|%return] [ARG ...]",
 #else
-		"[EVENT=]FUNC[+OFF|%return|:RL|;PT][@SRC]|SRC:AL|SRC;PT"
+		"[EVENT=]FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT"
 		" [ARG ...]",
 #endif
 		"probe point definition, where\n"