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envelope-from=steven.sistare@oracle.com; helo=mx0b-00069f02.pphosted.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_MED=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org During RUN_STATE_SUSPENDED, the cpu clock remains enabled, so the timers_state saved to the migration stream is stale, causing time errors in the guest when it wakes from suspend. To fix, maintain a shadow copy of timers_state, and update the shadow in a pre_save handler that uses the same logic found in cpu_disable_ticks. Copy the shadow to timers_state in post_load. Signed-off-by: Steve Sistare --- softmmu/cpu-timers.c | 36 +++++++++++++++++++++++++++++++++++- 1 file changed, 35 insertions(+), 1 deletion(-) diff --git a/softmmu/cpu-timers.c b/softmmu/cpu-timers.c index 117408c..d5af317 100644 --- a/softmmu/cpu-timers.c +++ b/softmmu/cpu-timers.c @@ -157,6 +157,36 @@ static bool icount_shift_state_needed(void *opaque) return icount_enabled() == 2; } +static int cpu_pre_save_ticks(void *opaque) +{ + TimersState *t = &timers_state; + TimersState *snap = opaque; + + seqlock_write_lock(&t->vm_clock_seqlock, &t->vm_clock_lock); + + if (t->cpu_ticks_enabled) { + snap->cpu_ticks_offset = t->cpu_ticks_offset + cpu_get_host_ticks(); + snap->cpu_clock_offset = cpu_get_clock_locked(); + } else { + snap->cpu_ticks_offset = t->cpu_ticks_offset; + snap->cpu_clock_offset = t->cpu_clock_offset; + } + seqlock_write_unlock(&t->vm_clock_seqlock, &t->vm_clock_lock); + return 0; +} + +static int cpu_post_load_ticks(void *opaque, int version_id) +{ + TimersState *t = &timers_state; + TimersState *snap = opaque; + + seqlock_write_lock(&t->vm_clock_seqlock, &t->vm_clock_lock); + t->cpu_ticks_offset = snap->cpu_ticks_offset; + t->cpu_clock_offset = snap->cpu_clock_offset; + seqlock_write_unlock(&t->vm_clock_seqlock, &t->vm_clock_lock); + return 0; +} + /* * Subsection for warp timer migration is optional, because may not be created */ @@ -221,6 +251,8 @@ static const VMStateDescription vmstate_timers = { .name = "timer", .version_id = 2, .minimum_version_id = 1, + .pre_save = cpu_pre_save_ticks, + .post_load = cpu_post_load_ticks, .fields = (VMStateField[]) { VMSTATE_INT64(cpu_ticks_offset, TimersState), VMSTATE_UNUSED(8), @@ -269,9 +301,11 @@ TimersState timers_state; /* initialize timers state and the cpu throttle for convenience */ void cpu_timers_init(void) { + static TimersState timers_snapshot; + seqlock_init(&timers_state.vm_clock_seqlock); qemu_spin_init(&timers_state.vm_clock_lock); - vmstate_register(NULL, 0, &vmstate_timers, &timers_state); + vmstate_register(NULL, 0, &vmstate_timers, &timers_snapshot); cpu_throttle_init(); }