---

yaml
---
r: 226170
b: refs/heads/master
c: 404a02c
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 1051b9f0f9eab8091fe3bf98320741adf36b4cfa
+refs/heads/master: 404a02cbd2ae8bf256a2fa1169bdfe86bb5ebb34

trunk/Documentation/accounting/getdelays.c

@@ -516,6 +516,7 @@ int main(int argc, char *argv[])
 			default:
 				fprintf(stderr, "Unknown nla_type %d\n",
 					na->nla_type);
+			case TASKSTATS_TYPE_NULL:
 				break;
 			}
 			na = (struct nlattr *) (GENLMSG_DATA(&msg) + len);

trunk/Documentation/arm/00-INDEX

@@ -34,3 +34,5 @@ memory.txt
 	- description of the virtual memory layout
 nwfpe/
 	- NWFPE floating point emulator documentation
+swp_emulation
+	- SWP/SWPB emulation handler/logging description

trunk/Documentation/arm/swp_emulation

@@ -0,0 +1,27 @@
+Software emulation of deprecated SWP instruction (CONFIG_SWP_EMULATE)
+---------------------------------------------------------------------
+
+ARMv6 architecture deprecates use of the SWP/SWPB instructions, and recommeds
+moving to the load-locked/store-conditional instructions LDREX and STREX.
+
+ARMv7 multiprocessing extensions introduce the ability to disable these
+instructions, triggering an undefined instruction exception when executed.
+Trapped instructions are emulated using an LDREX/STREX or LDREXB/STREXB
+sequence. If a memory access fault (an abort) occurs, a segmentation fault is
+signalled to the triggering process.
+
+/proc/cpu/swp_emulation holds some statistics/information, including the PID of
+the last process to trigger the emulation to be invocated. For example:
+---
+Emulated SWP:		12
+Emulated SWPB:		0
+Aborted SWP{B}:		1
+Last process:		314
+---
+
+NOTE: when accessing uncached shared regions, LDREX/STREX rely on an external
+transaction monitoring block called a global monitor to maintain update
+atomicity. If your system does not implement a global monitor, this option can
+cause programs that perform SWP operations to uncached memory to deadlock, as
+the STREX operation will always fail.
+