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| author | Arash Rouhani <rarash@student.chalmers.se> | 2014-09-01 15:13:57 -0500 |
|---|---|---|
| committer | Austin Seipp <austin@well-typed.com> | 2014-09-01 15:13:57 -0500 |
| commit | 2f343b0cbf8adf5b9df49c7a21f1914a38811dcf (patch) | |
| tree | 5fd51434c7f96b987ec1e7d5c824b70651e4061b /rts/ThreadPaused.c | |
| parent | 3be704ab373ecd84d97b832c0d4f59dd7cb9e0ea (diff) | |
| download | haskell-2f343b0cbf8adf5b9df49c7a21f1914a38811dcf.tar.gz | |
Refactor stack squeezing logic
Summary:
This patch is only to make the code easier to read.
In addition, this is the first patch I send with the arc/differential workflow.
So I start with something very small.
Test Plan: I have not even tried to compile it yet.
Reviewers: simonmar, austin
Reviewed By: austin
Subscribers: simonmar, ezyang, carter
Differential Revision: https://phabricator.haskell.org/D189
Diffstat (limited to 'rts/ThreadPaused.c')
| -rw-r--r-- | rts/ThreadPaused.c | 21 |
1 files changed, 13 insertions, 8 deletions
diff --git a/rts/ThreadPaused.c b/rts/ThreadPaused.c index bf7def4583..af37b53670 100644 --- a/rts/ThreadPaused.c +++ b/rts/ThreadPaused.c @@ -26,6 +26,7 @@ * * -------------------------------------------------------------------------- */ + struct stack_gap { StgWord gap_size; struct stack_gap *next_gap; }; static struct stack_gap * @@ -131,7 +132,7 @@ stackSqueeze(Capability *cap, StgTSO *tso, StgPtr bottom) adjacent_update_frames, gap); } - // Now we have a stack with gaps in it, and we have to walk down + // Now we have a stack with gap-structs in it, and we have to walk down // shoving the stack up to fill in the gaps. A diagram might // help: // @@ -200,6 +201,7 @@ threadPaused(Capability *cap, StgTSO *tso) nat weight = 0; nat weight_pending = 0; rtsBool prev_was_update_frame = rtsFalse; + StgWord heuristic_says_squeeze; // Check to see whether we have threads waiting to raise // exceptions, and we're not blocking exceptions, or are blocked @@ -358,17 +360,20 @@ threadPaused(Capability *cap, StgTSO *tso) } end: - debugTrace(DEBUG_squeeze, - "words_to_squeeze: %d, weight: %d, squeeze: %s", - words_to_squeeze, weight, - ((weight <= 8 && words_to_squeeze > 0) || weight < words_to_squeeze) ? "YES" : "NO"); - // Should we squeeze or not? Arbitrary heuristic: we squeeze if // the number of words we have to shift down is less than the // number of stack words we squeeze away by doing so. + // The threshold was bumped from 5 to 8 as a result of #2797 + heuristic_says_squeeze = ((weight <= 8 && words_to_squeeze > 0) + || weight < words_to_squeeze); + + debugTrace(DEBUG_squeeze, + "words_to_squeeze: %d, weight: %d, squeeze: %s", + words_to_squeeze, weight, + heuristic_says_squeeze ? "YES" : "NO"); + if (RtsFlags.GcFlags.squeezeUpdFrames == rtsTrue && - ((weight <= 8 && words_to_squeeze > 0) || weight < words_to_squeeze)) { - // threshold above bumped from 5 to 8 as a result of #2797 + heuristic_says_squeeze) { stackSqueeze(cap, tso, (StgPtr)frame); tso->flags |= TSO_SQUEEZED; // This flag tells threadStackOverflow() that the stack was |