qemu/include
David Hildenbrand 1f6493be08 s390x/tcg: MVCL: Exit to main loop if requested
MVCL is interruptible and we should check for interrupts and process
them after writing back the variables to the registers. Let's check
for any exit requests and exit to the main loop. Introduce a new helper
function for that: cpu_loop_exit_requested().

When booting Fedora 30, I can see a handful of these exits and it seems
to work reliable. Also, Richard explained why this works correctly even
when MVCL is called via EXECUTE:

    (1) TB with EXECUTE runs, at address Ae
        - env->psw_addr stored with Ae.
        - helper_ex() runs, memory address Am computed
          from D2a(X2a,B2a) or from psw.addr+RI2.
        - env->ex_value stored with memory value modified by R1a

    (2) TB of executee runs,
        - env->ex_value stored with 0.
        - helper_mvcl() runs, using and updating R1b, R1b+1, R2b, R2b+1.

    (3a) helper_mvcl() completes,
         - TB of executee continues, psw.addr += ilen.
         - Next instruction is the one following EXECUTE.

    (3b) helper_mvcl() exits to main loop,
         - cpu_loop_exit_restore() unwinds psw.addr = Ae.
         - Next instruction is the EXECUTE itself...
         - goto 1.

As the PoP mentiones that an interruptible instruction called via EXECUTE
should avoid modifying storage/registers that are used by EXECUTE itself,
it is fine to retrigger EXECUTE.

Cc: Alex Bennée <alex.bennee@linaro.org>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
2019-10-10 12:27:15 +02:00
..
authz Include generated QAPI headers less 2019-08-16 13:31:51 +02:00
block nbd: Grab aio context lock in more places 2019-09-24 07:30:19 -05:00
chardev Include qemu/main-loop.h less 2019-08-16 13:31:52 +02:00
crypto crypto: define cleanup functions for use with g_autoptr 2019-08-22 10:47:12 +01:00
disas include: Make headers more self-contained 2019-08-16 13:31:51 +02:00
exec s390x/tcg: MVCL: Exit to main loop if requested 2019-10-10 12:27:15 +02:00
fpu fpu: make softfloat-macros "self-contained" 2019-08-19 12:07:13 +01:00
hw ppc patch queue 2019-10-04 2019-10-07 13:49:02 +01:00
io socket: Add num connections to qio_net_listener_open_sync() 2019-09-03 23:24:42 +02:00
libdecnumber include: Make headers more self-contained 2019-08-16 13:31:51 +02:00
migration migration: register_savevm_live doesn't need dev 2019-09-12 11:15:03 +01:00
monitor Include hw/qdev-properties.h less 2019-08-16 13:31:53 +02:00
net Include qemu/queue.h slightly less 2019-08-16 13:31:52 +02:00
qapi qapi: Make visit_next_list()'s comment less confusing 2019-09-24 11:03:44 +02:00
qemu qemu/compiler.h: Add qemu_build_not_reached 2019-09-25 10:19:57 -07:00
qom hw/core: Move cpu.c, cpu.h from qom/ to hw/core/ 2019-08-21 13:24:01 +02:00
scsi scsi: explicitly list guest-recoverable sense codes 2019-07-15 11:20:42 +02:00
standard-headers kvm: i386: halt poll control MSR support 2019-08-20 17:26:17 +02:00
sysemu target/i386: expand feature words to 64 bits 2019-10-04 18:49:19 +02:00
ui ui/egl: fix framebuffer reads 2019-09-17 13:42:02 +02:00
elf.h linux-user: elf: ELF_HWCAP for s390x 2019-06-07 14:53:26 +02:00
glib-compat.h glib: bump min required glib library version to 2.48 2019-08-22 10:46:34 +01:00
qemu-common.h cutils: Move size_to_str() from "qemu-common.h" to "qemu/cutils.h" 2019-09-19 11:57:34 +02:00
qemu-io.h Include qemu-common.h exactly where needed 2019-06-12 13:20:20 +02:00
trace-tcg.h trace: get rid of generated-events.h/generated-events.c 2016-10-12 09:54:52 +02:00