Bug 1867190 - Add prefs for PHC probablities r=glandium

Differential Revision: https://phabricator.services.mozilla.com/D198652

UltraBlame original commit: ce5606473bf95f0899f69034525766ca9d0ed749

memory/build/PHC.cpp

@@ -3678,7 +3678,10 @@ return
 aRnd
 &
 (
+uint64_t
+(
 aAvgDelay
+)
 *
 2
 -
@@ -3689,6 +3692,88 @@ aAvgDelay
 1
 ;
 }
+constexpr
+Delay
+CheckProbability
+(
+int64_t
+aProb
+)
+{
+/
+/
+Limit
+delays
+calculated
+from
+prefs
+to
+0x80000000
+this
+is
+the
+largest
+/
+/
+power
+-
+of
+-
+two
+that
+fits
+in
+a
+Delay
+since
+it
+is
+a
+uint32_t
+.
+/
+/
+The
+minimum
+is
+2
+that
+way
+not
+every
+allocation
+goes
+straight
+to
+PHC
+.
+return
+RoundUpPow2
+(
+std
+:
+:
+min
+(
+std
+:
+:
+max
+(
+aProb
+int64_t
+(
+2
+)
+)
+int64_t
+(
+0x80000000
+)
+)
+)
+;
+}
 /
 /
 Maps
@@ -7234,6 +7319,48 @@ mPhcState
 aState
 ;
 }
+void
+SetProbabilities
+(
+int64_t
+aAvgDelayFirst
+int64_t
+aAvgDelayNormal
+int64_t
+aAvgDelayPageReuse
+)
+{
+MutexAutoLock
+lock
+(
+GMut
+:
+:
+sMutex
+)
+;
+mAvgFirstAllocDelay
+=
+CheckProbability
+(
+aAvgDelayFirst
+)
+;
+mAvgAllocDelay
+=
+CheckProbability
+(
+aAvgDelayNormal
+)
+;
+mAvgPageReuseDelay
+=
+CheckProbability
+(
+aAvgDelayPageReuse
+)
+;
+}
 private
 :
 template
@@ -14770,6 +14897,39 @@ aState
 )
 ;
 }
+void
+SetPHCProbabilities
+(
+int64_t
+aAvgDelayFirst
+int64_t
+aAvgDelayNormal
+int64_t
+aAvgDelayPageReuse
+)
+{
+if
+(
+!
+maybe_init
+(
+)
+)
+{
+return
+;
+}
+gMut
+-
+>
+SetProbabilities
+(
+aAvgDelayFirst
+aAvgDelayNormal
+aAvgDelayPageReuse
+)
+;
+}
 }
 /
 /

memory/build/PHC.h

@@ -979,6 +979,18 @@ PHCState
 aState
 )
 ;
+MOZ_JEMALLOC_API
+void
+SetPHCProbabilities
+(
+int64_t
+aAvgDelayFirst
+int64_t
+aAvgDelayNormal
+int64_t
+aAvgDelayPageReuse
+)
+;
 struct
 MemoryUsage
 {

modules/libpref/init/StaticPrefList.yaml

@@ -66759,6 +66759,63 @@ value
 mirror
 :
 always
+-
+name
+:
+memory
+.
+phc
+.
+avg_delay
+.
+first
+type
+:
+uint32_t
+value
+:
+65536
+mirror
+:
+always
+-
+name
+:
+memory
+.
+phc
+.
+avg_delay
+.
+normal
+type
+:
+uint32_t
+value
+:
+16384
+mirror
+:
+always
+-
+name
+:
+memory
+.
+phc
+.
+avg_delay
+.
+page_reuse
+type
+:
+uint32_t
+value
+:
+262144
+mirror
+:
+always
 #
 -
 -

toolkit/components/nimbus/FeatureManifest.yaml

@@ -14349,6 +14349,88 @@ memory
 phc
 .
 min_ram_mb
+phcAvgDelayFirst
+:
+description
+:
+The
+delay
+before
+the
+first
+PHC
+allocation
+type
+:
+int
+setPref
+:
+branch
+:
+user
+pref
+:
+memory
+.
+phc
+.
+avg_delay
+.
+first
+phcAvgDelayNormal
+:
+description
+:
+The
+delay
+between
+PHC
+allocations
+type
+:
+int
+setPref
+:
+branch
+:
+user
+pref
+:
+memory
+.
+phc
+.
+avg_delay
+.
+normal
+phcAvgDelayPageReuse
+:
+description
+:
+The
+delay
+before
+reusing
+a
+PHC
+page
+type
+:
+int
+setPref
+:
+branch
+:
+user
+pref
+:
+memory
+.
+phc
+.
+avg_delay
+.
+page_reuse
 mailto
 :
 description