summaryrefslogtreecommitdiff
path: root/includes/rts/prof/CCS.h
diff options
context:
space:
mode:
authorSimon Marlow <marlowsd@gmail.com>2011-11-28 16:48:43 +0000
committerSimon Marlow <marlowsd@gmail.com>2011-11-29 12:21:18 +0000
commit50de6034343abc93a7b01daccff34121042c0e7c (patch)
tree24496a5fc6bc39c6baaa574608e53c5d76c169f6 /includes/rts/prof/CCS.h
parent1c2b838131134d44004dfdff18c302131478390d (diff)
downloadhaskell-50de6034343abc93a7b01daccff34121042c0e7c.tar.gz
Make profiling work with multiple capabilities (+RTS -N)
This means that both time and heap profiling work for parallel programs. Main internal changes: - CCCS is no longer a global variable; it is now another pseudo-register in the StgRegTable struct. Thus every Capability has its own CCCS. - There is a new built-in CCS called "IDLE", which records ticks for Capabilities in the idle state. If you profile a single-threaded program with +RTS -N2, you'll see about 50% of time in "IDLE". - There is appropriate locking in rts/Profiling.c to protect the shared cost-centre-stack data structures. This patch does enough to get it working, I have cut one big corner: the cost-centre-stack data structure is still shared amongst all Capabilities, which means that multiple Capabilities will race when updating the "allocations" and "entries" fields of a CCS. Not only does this give unpredictable results, but it runs very slowly due to cache line bouncing. It is strongly recommended that you use -fno-prof-count-entries to disable the "entries" count when profiling parallel programs. (I shall add a note to this effect to the docs).
Diffstat (limited to 'includes/rts/prof/CCS.h')
-rw-r--r--includes/rts/prof/CCS.h7
1 files changed, 4 insertions, 3 deletions
diff --git a/includes/rts/prof/CCS.h b/includes/rts/prof/CCS.h
index 4692d166b5..9737fc9c18 100644
--- a/includes/rts/prof/CCS.h
+++ b/includes/rts/prof/CCS.h
@@ -114,8 +114,6 @@ typedef struct _IndexTable {
Pre-defined cost centres and cost centre stacks
-------------------------------------------------------------------------- */
-extern CostCentreStack * RTS_VAR(CCCS); /* current CCS */
-
#if IN_STG_CODE
extern StgWord CC_MAIN[];
@@ -153,6 +151,9 @@ extern CostCentreStack CCS_DONT_CARE[]; // shouldn't ever get set
extern CostCentre CC_PINNED[];
extern CostCentreStack CCS_PINNED[]; // pinned memory
+extern CostCentre CC_IDLE[];
+extern CostCentreStack CCS_IDLE[]; // capability is idle
+
#endif /* IN_STG_CODE */
extern unsigned int RTS_VAR(CC_ID); // global ids
@@ -165,7 +166,7 @@ extern unsigned int RTS_VAR(era);
* ---------------------------------------------------------------------------*/
CostCentreStack * pushCostCentre (CostCentreStack *, CostCentre *);
-void enterFunCCS (CostCentreStack *);
+void enterFunCCS (StgRegTable *reg, CostCentreStack *);
/* -----------------------------------------------------------------------------
Registering CCs and CCSs