Author: jeff
Date: Mon Dec 16 20:15:04 2019
New Revision: 355819
URL: https://svnweb.freebsd.org/changeset/base/355819
Log:
Repeat the spinlock_enter/exit pattern from amd64 on other architectures to
fix an assert violation introduced in r355784. Without this spinlock_exit()
may see owepreempt and switch before reducing the spinlock count. amd64
had been optimized to do a single critical enter/exit regardless of the
number of spinlocks which avoided the problem and this optimization had
not been applied elsewhere.
Reported by: emaste
Suggested by: rlibby
Discussed with: jhb, rlibby
Tested by: manu (arm64)
Modified:
head/sys/arm/arm/machdep.c
head/sys/arm64/arm64/machdep.c
head/sys/i386/i386/machdep.c
head/sys/mips/mips/machdep.c
head/sys/powerpc/powerpc/machdep.c
head/sys/riscv/riscv/machdep.c
Modified: head/sys/arm/arm/machdep.c
==============================================================================
--- head/sys/arm/arm/machdep.c Mon Dec 16 20:07:04 2019 (r355818)
+++ head/sys/arm/arm/machdep.c Mon Dec 16 20:15:04 2019 (r355819)
@@ -389,9 +389,9 @@ spinlock_enter(void)
cspr = disable_interrupts(PSR_I | PSR_F);
td->td_md.md_spinlock_count = 1;
td->td_md.md_saved_cspr = cspr;
+ critical_enter();
} else
td->td_md.md_spinlock_count++;
- critical_enter();
}
void
@@ -401,11 +401,12 @@ spinlock_exit(void)
register_t cspr;
td = curthread;
- critical_exit();
cspr = td->td_md.md_saved_cspr;
td->td_md.md_spinlock_count--;
- if (td->td_md.md_spinlock_count == 0)
+ if (td->td_md.md_spinlock_count == 0) {
+ critical_exit();
restore_interrupts(cspr);
+ }
}
/*
Modified: head/sys/arm64/arm64/machdep.c
==============================================================================
--- head/sys/arm64/arm64/machdep.c Mon Dec 16 20:07:04 2019
(r355818)
+++ head/sys/arm64/arm64/machdep.c Mon Dec 16 20:15:04 2019
(r355819)
@@ -635,9 +635,9 @@ spinlock_enter(void)
daif = intr_disable();
td->td_md.md_spinlock_count = 1;
td->td_md.md_saved_daif = daif;
+ critical_enter();
} else
td->td_md.md_spinlock_count++;
- critical_enter();
}
void
@@ -647,11 +647,12 @@ spinlock_exit(void)
register_t daif;
td = curthread;
- critical_exit();
daif = td->td_md.md_saved_daif;
td->td_md.md_spinlock_count--;
- if (td->td_md.md_spinlock_count == 0)
+ if (td->td_md.md_spinlock_count == 0) {
+ critical_exit();
intr_restore(daif);
+ }
}
#ifndef _SYS_SYSPROTO_H_
Modified: head/sys/i386/i386/machdep.c
==============================================================================
--- head/sys/i386/i386/machdep.c Mon Dec 16 20:07:04 2019
(r355818)
+++ head/sys/i386/i386/machdep.c Mon Dec 16 20:15:04 2019
(r355819)
@@ -2679,9 +2679,9 @@ spinlock_enter(void)
flags = intr_disable();
td->td_md.md_spinlock_count = 1;
td->td_md.md_saved_flags = flags;
+ critical_enter();
} else
td->td_md.md_spinlock_count++;
- critical_enter();
}
void
@@ -2691,11 +2691,12 @@ spinlock_exit(void)
register_t flags;
td = curthread;
- critical_exit();
flags = td->td_md.md_saved_flags;
td->td_md.md_spinlock_count--;
- if (td->td_md.md_spinlock_count == 0)
+ if (td->td_md.md_spinlock_count == 0) {
+ critical_exit();
intr_restore(flags);
+ }
}
#if defined(I586_CPU) && !defined(NO_F00F_HACK)
Modified: head/sys/mips/mips/machdep.c
==============================================================================
--- head/sys/mips/mips/machdep.c Mon Dec 16 20:07:04 2019
(r355818)
+++ head/sys/mips/mips/machdep.c Mon Dec 16 20:15:04 2019
(r355819)
@@ -516,9 +516,9 @@ spinlock_enter(void)
intr = intr_disable();
td->td_md.md_spinlock_count = 1;
td->td_md.md_saved_intr = intr;
+ critical_enter();
} else
td->td_md.md_spinlock_count++;
- critical_enter();
}
void
@@ -528,11 +528,12 @@ spinlock_exit(void)
register_t intr;
td = curthread;
- critical_exit();
intr = td->td_md.md_saved_intr;
td->td_md.md_spinlock_count--;
- if (td->td_md.md_spinlock_count == 0)
+ if (td->td_md.md_spinlock_count == 0) {
+ critical_exit();
intr_restore(intr);
+ }
}
/*
Modified: head/sys/powerpc/powerpc/machdep.c
==============================================================================
--- head/sys/powerpc/powerpc/machdep.c Mon Dec 16 20:07:04 2019
(r355818)
+++ head/sys/powerpc/powerpc/machdep.c Mon Dec 16 20:15:04 2019
(r355819)
@@ -499,9 +499,9 @@ spinlock_enter(void)
msr = intr_disable();
td->td_md.md_spinlock_count = 1;
td->td_md.md_saved_msr = msr;
+ critical_enter();
} else
td->td_md.md_spinlock_count++;
- critical_enter();
}
void
@@ -511,10 +511,10 @@ spinlock_exit(void)
register_t msr;
td = curthread;
- critical_exit();
msr = td->td_md.md_saved_msr;
td->td_md.md_spinlock_count--;
if (td->td_md.md_spinlock_count == 0) {
+ critical_exit();
intr_restore(msr);
nop_prio_medium();
}
Modified: head/sys/riscv/riscv/machdep.c
==============================================================================
--- head/sys/riscv/riscv/machdep.c Mon Dec 16 20:07:04 2019
(r355818)
+++ head/sys/riscv/riscv/machdep.c Mon Dec 16 20:15:04 2019
(r355819)
@@ -489,9 +489,9 @@ spinlock_enter(void)
reg = intr_disable();
td->td_md.md_spinlock_count = 1;
td->td_md.md_saved_sstatus_ie = reg;
+ critical_enter();
} else
td->td_md.md_spinlock_count++;
- critical_enter();
}
void
@@ -501,11 +501,12 @@ spinlock_exit(void)
register_t sstatus_ie;
td = curthread;
- critical_exit();
sstatus_ie = td->td_md.md_saved_sstatus_ie;
td->td_md.md_spinlock_count--;
- if (td->td_md.md_spinlock_count == 0)
+ if (td->td_md.md_spinlock_count == 0) {
+ critical_exit();
intr_restore(sstatus_ie);
+ }
}
#ifndef _SYS_SYSPROTO_H_
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