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| author | Jeff Roberson <jeff@FreeBSD.org> | 2019-12-16 20:15:04 +0000 |
|---|---|---|
| committer | Jeff Roberson <jeff@FreeBSD.org> | 2019-12-16 20:15:04 +0000 |
| commit | a94ba188c3443d90bad4a1d29bb477a7760c7267 (patch) | |
| tree | d15d0bf3a1e0cef48b7e615d7101a69dd0e45141 /sys/i386 | |
| parent | b5f20658ee91b62296384ec68cd1fc82a4fbe4bb (diff) | |
| download | src-a94ba188c3443d90bad4a1d29bb477a7760c7267.tar.gz src-a94ba188c3443d90bad4a1d29bb477a7760c7267.zip | |
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)
Notes
Notes:
svn path=/head/; revision=355819
Diffstat (limited to 'sys/i386')
| -rw-r--r-- | sys/i386/i386/machdep.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/sys/i386/i386/machdep.c b/sys/i386/i386/machdep.c index 60ebb3a3510e..b6a960ee0d10 100644 --- a/sys/i386/i386/machdep.c +++ b/sys/i386/i386/machdep.c @@ -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) |