Hello, For perfmon, we need a couple of TIF bits. It seems that with 2.6.22-rc2 there is now a TIF_RESTORE_SIGMASK which uses the last remaining bit in the first 7 bits of the thread flag. Many architectures, including IA-64, rely on the fact that some of the TIF flags (TIF_ALL_WORKMASK or TIF_ALL_WORK) tested on kernel exit reside in the low 8-bit or 7-bit because they use instructions (such as add r1=imm8,r2 on IA-64) which operate on 8 or 7 bit immediate. On IA-64, adding that one perfmon flag (as bit 7) would cause some restructuring in the kernel exit path but also in all the lightweight syscall handlers. I looked at all the low order TIF flags and found that TIF_NOTIFY_RESUME was never set nor used anywhere in any architecture. Is that really the case? If so, we could get rid of it and free up one low-order TIF bit. Thanks. -- -Stephane - To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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