oritm at mellanox.com
Tue May 7 07:05:00 UTC 2013
I read a bit about the FreeBSD mutex implementation for spinlock.
I might be wrong, but I noticed a code section that might be problematic:
Taken from http://svn.freebsd.org/base/release/9.1.0/sys/ofed/include/linux/spinlock.h:
static inline void
memset(&lock->m, 0, sizeof(lock->m));
mtx_init(&lock->m, "lnxspin", NULL, MTX_DEF | MTX_NOWITNESS);
But MTX_DEF initializes mutex as a sleep mutex:
By default, MTX_DEF mutexes will context switch when they are already
There is a flag MTX_SPIN Which I think is the right one in this case .
I'd appreciate your take on this issue.
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