On 02/28/2013 11:24 AM, Maarten Lankhorst wrote:
This will allow me to call functions that have multiple arguments if fastpath fails. This is required to support ticket mutexes, because they need to be able to pass an extra argument to the fail function.
Originally I duplicated the functions, by adding __mutex_fastpath_lock_retval_arg. This ended up being just a duplication of the existing function, so a way to test if fastpath was called ended up being better.
This also cleaned up the reservation mutex patch some by being able to call an atomic_set instead of atomic_xchg, and making it easier to detect if the wrong unlock function was previously used.
Signed-off-by: Maarten Lankhorst maarten.lankhorst@canonical.com
arch/ia64/include/asm/mutex.h | 10 ++++------ arch/powerpc/include/asm/mutex.h | 10 ++++------ arch/sh/include/asm/mutex-llsc.h | 4 ++-- arch/x86/include/asm/mutex_32.h | 11 ++++------- arch/x86/include/asm/mutex_64.h | 11 ++++------- include/asm-generic/mutex-dec.h | 10 ++++------ include/asm-generic/mutex-null.h | 2 +- include/asm-generic/mutex-xchg.h | 10 ++++------ kernel/mutex.c | 32 ++++++++++++++------------------ 9 files changed, 41 insertions(+), 59 deletions(-)
[...]
diff --git a/arch/x86/include/asm/mutex_32.h b/arch/x86/include/asm/mutex_32.h index 03f90c8..b7f6b34 100644 --- a/arch/x86/include/asm/mutex_32.h +++ b/arch/x86/include/asm/mutex_32.h @@ -42,17 +42,14 @@ do { \
- __mutex_fastpath_lock_retval - try to take the lock by moving the count
from 1 to a 0 value- @count: pointer of type atomic_t
- @fail_fn: function to call if the original value was not 1
- Change the count from 1 to a value lower than 1, and call <fail_fn> if it
- wasn't 1 originally. This function returns 0 if the fastpath succeeds,
- or anything the slow path function returns
- Change the count from 1 to a value lower than 1. This function returns 0
- if the fastpath succeeds, or 1 otherwise.
The minus sign is missing, the return value should be -1.
[...]
diff --git a/include/asm-generic/mutex-null.h b/include/asm-generic/mutex-null.h index e1bbbc7..efd6206 100644 --- a/include/asm-generic/mutex-null.h +++ b/include/asm-generic/mutex-null.h @@ -11,7 +11,7 @@ #define _ASM_GENERIC_MUTEX_NULL_H #define __mutex_fastpath_lock(count, fail_fn) fail_fn(count) -#define __mutex_fastpath_lock_retval(count, fail_fn) fail_fn(count) +#define __mutex_fastpath_lock_retval(count, fail_fn) (-1)
The fail_fn parameter should be dropped here as well.
Regards, Francesco