Patchwork libitm: Clarify ABI requirements for data-logging functions.

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Submitter Torvald Riegel
Date Oct. 23, 2012, 3:50 p.m.
Message ID <1351007448.3374.10910.camel@triegel.csb>
Download mbox | patch
Permalink /patch/193519/
State New
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Comments

Torvald Riegel - Oct. 23, 2012, 3:50 p.m.
This patch clarifies the ABI requirements for data-logging functions in
libitm's documentation.  Thanks to Luke Dalessandro for pointing this
out.

OK for trunk?

Torvald
commit b9cbb260f958f53afbea69675458f3f15a04b812
Author: Torvald Riegel <triegel@redhat.com>
Date:   Tue Oct 23 14:56:32 2012 +0200

    Clarify ABI requirements for data-logging functions.
    
    	* libitm.texi: Clarify ABI requirements for data-logging functions.
Richard Henderson - Oct. 23, 2012, 9:28 p.m.
On 2012-10-24 01:50, Torvald Riegel wrote:
>     Clarify ABI requirements for data-logging functions.
>     
>     	* libitm.texi: Clarify ABI requirements for data-logging functions.

Ok.


r~

Patch

diff --git a/libitm/libitm.texi b/libitm/libitm.texi
index 6cfcaf9..7e5c413 100644
--- a/libitm/libitm.texi
+++ b/libitm/libitm.texi
@@ -156,6 +156,13 @@  about which memory locations are shared and which are not shared with other
 threads (i.e., data must be accessed either transactionally or
 nontransactionally). Otherwise, non-write-through TM algorithms would not work.
 
+For memory locations on the stack, this requirement extends to only the
+lifetime of the stack frame that the memory location belongs to (or the
+lifetime of the transaction, whichever is shorter).  Thus, memory that is
+reused for several stack frames could be target of both data logging and
+transactional accesses; however, this is harmless because these stack frames'
+lifetimes will end before the transaction finishes.
+
 @subsection [No changes] Scatter/gather calls
 @subsection [No changes] Serial and irrevocable mode
 @subsection [No changes] Transaction descriptor