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From: Steven Rostedt <rostedt@goodmis.org>
To: linux-kernel@vger.kernel.org
Cc: Ingo Molnar <mingo@kernel.org>,
	Frederic Weisbecker <fweisbec@gmail.com>,
	Andrew Morton <akpm@linux-foundation.org>
Subject: [for-next][PATCH 09/13] ftrace/x86: Get the current mcount addr for add_breakpoint()
Date: Mon, 12 May 2014 11:11:39 -0400	[thread overview]
Message-ID: <20140512151204.025712167@goodmis.org> (raw)
In-Reply-To: 20140512151130.345864843@goodmis.org

[-- Attachment #1: 0009-ftrace-x86-Get-the-current-mcount-addr-for-add_break.patch --]
[-- Type: text/plain, Size: 1424 bytes --]

From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>

The add_breakpoint() code in the ftrace updating gets the address
of what the call will become, but if the mcount address is changing
from regs to non-regs ftrace_caller or vice versa, it will use what
the record currently is.

This is rather silly as the code should always use what is currently
there regardless of if it's changing the regs function or just converting
to a nop.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 arch/x86/kernel/ftrace.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index 3d837b0..4b3c195 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -380,9 +380,9 @@ static int add_breakpoints(struct dyn_ftrace *rec, int enable)
 	unsigned long ftrace_addr;
 	int ret;
 
-	ret = ftrace_test_record(rec, enable);
+	ftrace_addr = get_ftrace_old_addr(rec);
 
-	ftrace_addr = get_ftrace_addr(rec);
+	ret = ftrace_test_record(rec, enable);
 
 	switch (ret) {
 	case FTRACE_UPDATE_IGNORE:
@@ -394,8 +394,6 @@ static int add_breakpoints(struct dyn_ftrace *rec, int enable)
 
 	case FTRACE_UPDATE_MODIFY_CALL_REGS:
 	case FTRACE_UPDATE_MODIFY_CALL:
-		ftrace_addr = get_ftrace_old_addr(rec);
-		/* fall through */
 	case FTRACE_UPDATE_MAKE_NOP:
 		/* converting a call to a nop */
 		return add_brk_on_call(rec, ftrace_addr);
-- 
1.8.5.3



  parent reply	other threads:[~2014-05-12 15:13 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-05-12 15:11 [for-next][PATCH 00/13] tracing: More updates for 3.16 Steven Rostedt
2014-05-12 15:11 ` [for-next][PATCH 01/13] ftrace: Have function graph tracer use global_ops for filtering Steven Rostedt
2014-05-12 15:11 ` [for-next][PATCH 02/13] tracing: Remove myself as a tracing maintainer Steven Rostedt
2014-05-12 15:11 ` [for-next][PATCH 03/13] tracing: Replace __get_cpu_var uses with this_cpu_ptr Steven Rostedt
2014-05-12 15:11 ` [for-next][PATCH 04/13] tracing: Add trace_<tracepoint>_enabled() function Steven Rostedt
2014-05-12 15:11 ` [for-next][PATCH 05/13] tracing: Add __bitmask() macro to trace events to cpumasks and other bitmasks Steven Rostedt
2014-05-12 15:11 ` [for-next][PATCH 06/13] ftrace: Remove boolean of hash_enable and hash_disable Steven Rostedt
2014-05-12 15:11 ` [for-next][PATCH 07/13] ftrace: Write in missing comment from a very old commit Steven Rostedt
2014-05-12 15:11 ` [for-next][PATCH 08/13] ftrace: Always inline ftrace_hash_empty() helper function Steven Rostedt
2014-05-12 15:11 ` Steven Rostedt [this message]
2014-05-12 15:11 ` [for-next][PATCH 10/13] ftrace: Make get_ftrace_addr() and get_ftrace_addr_old() global Steven Rostedt
2014-05-12 15:11 ` [for-next][PATCH 11/13] ftrace: Use the ftrace_addr helper functions to find the ftrace_addr Steven Rostedt
2014-05-12 15:11 ` [for-next][PATCH 12/13] ftrace: Remove FTRACE_UPDATE_MODIFY_CALL_REGS flag Steven Rostedt
2014-05-12 15:11 ` [for-next][PATCH 13/13] ftrace/x86: Move the mcount/fentry code out of entry_64.S Steven Rostedt

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