This applies to: git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux.git seccomp-fastpath Gitweb: https://git.kernel.org/cgit/linux/kernel/git/kees/linux.git/log/?h=seccomp/fastpath This is both a cleanup and a speedup. It reduces overhead due to installing a trivial seccomp filter by 87%. The speedup comes from avoiding the full syscall tracing mechanism for filters that don't return SECCOMP_RET_TRACE. This series depends on splitting the seccomp hooks into two phases. The first phase evaluates the filter; it can skip syscalls, allow them, kill the calling task, or pass a u32 to the second phase. The second phase requires a full tracing context, and it sends ptrace events if necessary. The seccomp core part is in Kees' seccomp/fastpath tree. These patches implement a similar split for the x86 syscall entry work. The C callback is invoked in two phases: the first has only a partial frame, and it can request phase 2 processing with a full frame. Finally, I switch the 64-bit system_call code to use the new split entry work. This is a net deletion of assembly code: it replaces all of the audit entry muck. In the process, I fixed some bugs. If this is acceptable, someone can do the same tweak for the ia32entry and entry_32 code. This passes all seccomp tests that I know of. Changes from v3: - Dropped the core seccomp changes from the email -- Kees has applied them. - Add patch 2 (the TIF_NOHZ change). - Fix TIF_NOHZ in the two-phase entry code (thanks, Oleg). Changes from v2: - Fixed 32-bit x86 build (and the tests pass). - Put the doc patch where it belongs. Changes from v1: - Rebased on top of Kees' shiny new seccomp tree (no effect on the x86 part). - Improved patch 6 vs patch 7 split (thanks Alexei!) - Fixed bogus -ENOSYS in patch 5 (thanks Kees!) - Improved changelog message in patch 6. Changes from RFC version: - The first three patches are more or less the same - The rest is more or less a rewrite Andy Lutomirski (5): x86,x32,audit: Fix x32's AUDIT_ARCH wrt audit x86,entry: Only call user_exit if TIF_NOHZ x86: Split syscall_trace_enter into two phases x86_64,entry: Treat regs->ax the same in fastpath and slowpath syscalls x86_64,entry: Use split-phase syscall_trace_enter for 64-bit syscalls arch/x86/include/asm/calling.h | 6 +- arch/x86/include/asm/ptrace.h | 5 ++ arch/x86/kernel/entry_64.S | 51 +++++-------- arch/x86/kernel/ptrace.c | 159 ++++++++++++++++++++++++++++++++++------- 4 files changed, 161 insertions(+), 60 deletions(-) -- 1.9.3
