Message ID | 20201203171528.83180-1-msc@linux.ibm.com |
---|---|
Headers | show |
Series | powerpc: Add support for system call vectored | expand |
Hi Matheus, Worked on top of Adhemerval's brk patch. But it fails if applied directly on master. Tested on a POWER9 with and without scv support. Tested-by: Lucas A. M. Magalhães <lamm@linux.ibm.com> Quoting Matheus Castanho via Libc-alpha (2020-12-03 14:15:26) > This patchset enables the usage of system call vectored (scv) instruction by > system calls for improved performance on POWER9 and later processors. > > This new version dropped the patch to move brk to a C-based implementation, in > favor of Adhemerval's patch [0]. So it should be applied on top of that. > > Also, it modified the scv check mechanism to remove the thread pointer check as > suggested by Florian. Now the dynamic loader always uses sc, static code still > checks the thread pointer before accessing the TCB, and shared code (outside the > dl) accesses the TCB directly. > > Please check each patch for more details, specially 1/2 which explains the > rationale and details of the runtime mechanism to choose between the old > behavior (sc) and the new one (scv 0). > > Tested on powerpc, powerpc64, and powerpc64le (with and without scv) > > [0] https://sourceware.org/pipermail/libc-alpha/2020-November/119770.html > > --- > > v2: > - Fix typos and comments to match GNU style > - Remove the check for the thread pointer on shared code, and always use sc > when inside the dynamic loader > - Drop the patch implementing brk in C > > Matheus Castanho (2): > powerpc: Runtime selection between sc and scv for syscalls > powerpc: Use scv instruction on clone when available > > sysdeps/powerpc/powerpc32/sysdep.h | 15 ++- > sysdeps/powerpc/powerpc64/sysdep.h | 120 +++++++++++++++++- > .../unix/sysv/linux/powerpc/powerpc64/clone.S | 36 +++++- > .../unix/sysv/linux/powerpc/powerpc64/vfork.S | 6 +- > sysdeps/unix/sysv/linux/powerpc/syscall.S | 11 +- > sysdeps/unix/sysv/linux/powerpc/sysdep.h | 93 ++++++++++---- > 6 files changed, 241 insertions(+), 40 deletions(-) > > -- > 2.26.2