[PATCH] x86: Don't use the strict copy checks when branch profiling is in use

From: Arjan van de Ven
Date: Tue Oct 06 2009 - 10:02:10 EST


The branch profiling creates very complex code for each if statement,
to the point that gcc has trouble even analyzing something as simple
as

if (count > 5)
count = 5;

This then means that causing an error on code that gcc cannot analyze
for copy_from_user() and co is not very productive.

This patch excludes the strict copy checks in the case of branch
profiling being enabled.

Signed-off-by: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
---
arch/x86/Kconfig.debug | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug
index 1bd2e36..fb772b6 100644
--- a/arch/x86/Kconfig.debug
+++ b/arch/x86/Kconfig.debug
@@ -289,7 +289,7 @@ config OPTIMIZE_INLINING

config DEBUG_STRICT_USER_COPY_CHECKS
bool "Strict copy size checks"
- depends on DEBUG_KERNEL
+ depends on DEBUG_KERNEL && !TRACE_BRANCH_PROFILING
---help---
Enabling this option turns a certain set of sanity checks for user
copy operations into compile time failures.
--
1.6.2.5


--
Arjan van de Ven Intel Open Source Technology Centre
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