On 10/20/06, Weldon Washburn <[EMAIL PROTECTED]> wrote:
Evgueni, Please also test on Linux. This looks like a reasonable patch to me.
Unfortunately, I don't have access to Linux today (work from home).
Regarding the 16-bit CAS. A long time ago, there was a 16-bit, byte-aligned field for thread ID. monenter() would do a 16-bit CAS. Maybe this is left over from old monenter()??
There is still 16-bit field for Thread ID which keeps ID of the thread holding object lock. port_atomic_cas16 is used to operate with it...As Artem said susped_request field used to be 16-bit value some time ago. I think that's the main reason why 16-bit CAS was used. Seems like somebody changed 16-bit value to 32-bit but failed to fix atomic dec/inc operations. Evgueni
On 10/19/06, Artem Aliev <[EMAIL PROTECTED]> wrote: > > Eugeny, > > > The problem can be easily fixed by changing int16 to unit16 in > > atomic16_dec. Do you think this is accaptable way to fix the problem. > > > > BTW, could somebody explain why 16-bit atomic operation is used for > > 32-bit value? > The suspend_request could be 16bit value some time ago. > Could you please file a JIRA issue with a patch. > It looks reasonable to replace inc16 by inc32 as a fix. > > > Thanks > Artem > > > > > On 10/19/06, Evgueni Brevnov <[EMAIL PROTECTED]> wrote: > > Hi, > > > > Today, I had several hangs of cunit tests. It turned out to be > > infinite cycling in > > while loop of atomic16_inc/atomic16_dec (see > > vm/thread/src/thread_native_suspend.c) > > > > Here is a snip of assembler code produced by msvc for atomic16_dec: > > > > call port_atomic_cas16 (10004A90h) > > add esp,0Ch > > movzx edx,ax <-----------------------------zero extention > > movsx eax,word ptr [old_value] <----sign extention > > cmp edx,eax > > je atomic16_inc+45h (10004A15h) > > > > The problem can be easily fixed by changing int16 to unit16 in > > atomic16_dec. Do you think this is accaptable way to fix the problem. > > > > BTW, could somebody explain why 16-bit atomic operation is used for > > 32-bit value? > > > > Thanks > > Evgueni > > > > --------------------------------------------------------------------- > > Terms of use : http://incubator.apache.org/harmony/mailing.html > > To unsubscribe, e-mail: [EMAIL PROTECTED] > > For additional commands, e-mail: [EMAIL PROTECTED] > > > > > > --------------------------------------------------------------------- > Terms of use : http://incubator.apache.org/harmony/mailing.html > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > > -- Weldon Washburn Intel Middleware Products Division
--------------------------------------------------------------------- Terms of use : http://incubator.apache.org/harmony/mailing.html To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
