On 6/10/05, lk <linux_kernel@xxxxxxxxx> wrote: > >i remember filling GDT with TLS segments for glibc. what does this > >segment mean ? is it that the glibc libraries are found in this > >segment ? > > here is my view > TLS is a thread local storage segment, this concept is used in threading > abstractions to store the > per thread local data. > yes, when we fill the GDT there is also an entry for the pointer in TLS > segment #1 descriptor. The _thread extension is already supported by > glibc.The kernel keeps a specific per thread GDT entry that can be set up > and modified by each thread. > The kernel upon context switch, modifies this GDT entry to match that of the > thread's TLS setting.this way user space threaded code can access per thread > data via this descriptor > > regards > lk > can u throw some light on " _thread extension is already supported by glibc " what per thread data are we speaking about ? again how is it different from a TSS ? -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
