Messages in this thread Patch in this message | | | From | Andi Kleen <> | Subject | [PATCH 12/29] x86, tsx: Add a per thread transaction disable count | Date | Fri, 22 Mar 2013 18:25:06 -0700 |
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From: Andi Kleen <ak@linux.intel.com>
For some locks that have a low chance of not aborting it's best to just disable transactions.
Add a counter to thread_info to allow to disable tranasctions for the current task.
I originally experimented with more complicated solutions, like a magic spinlock type to disable with magic type matching, but that was very intrusive in the locking code.
This setup -- while adding a few more instructions -- is more flexible and seems to work quite nicely.
Signed-off-by: Andi Kleen <ak@linux.intel.com> --- arch/x86/include/asm/thread_info.h | 8 ++++++++ 1 files changed, 8 insertions(+), 0 deletions(-)
diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h index 2cd056e..91bb84e 100644 --- a/arch/x86/include/asm/thread_info.h +++ b/arch/x86/include/asm/thread_info.h @@ -39,6 +39,7 @@ struct thread_info { */ __u8 supervisor_stack[0]; #endif + unsigned notxn; /* transactions are disabled */ unsigned int sig_on_uaccess_error:1; unsigned int uaccess_err:1; /* uaccess failed */ }; @@ -279,6 +280,13 @@ static inline bool is_ia32_task(void) #endif return false; } + +#ifdef CONFIG_RTM_LOCKS +#define txn_disabled() (current_thread_info()->notxn) +#define disable_txn() (current_thread_info()->notxn++) +#define reenable_txn() (current_thread_info()->notxn--) +#endif + #endif /* !__ASSEMBLY__ */ #ifndef __ASSEMBLY__ -- 1.7.7.6
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