Writes to interrupt_request used non-atomic accesses, but there are a
few cases where the access was not protected by the BQL. Now that
there is a full set of helpers, it's easier to guarantee that
interrupt_request accesses are fully atomic, so just drop the
requirement instead of fixing them.
Reviewed-by: Igor Mammedov <imamm...@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <phi...@linaro.org>
Reviewed-by: Richard Henderson <richard.hender...@linaro.org>
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
include/hw/core/cpu.h | 1 -
hw/core/cpu-common.c | 12 +-----------
system/cpus.c | 3 +--
3 files changed, 2 insertions(+), 14 deletions(-)
diff --git a/include/hw/core/cpu.h b/include/hw/core/cpu.h
index b01a0cffd64..23bd02277f4 100644
--- a/include/hw/core/cpu.h
+++ b/include/hw/core/cpu.h
@@ -495,7 +495,6 @@ struct CPUState {
bool exit_request;
int exclusive_context_count;
uint32_t cflags_next_tb;
- /* updates protected by BQL */
uint32_t interrupt_request;
int singlestep_enabled;
int64_t icount_budget;
diff --git a/hw/core/cpu-common.c b/hw/core/cpu-common.c
index 259cf2a3c36..152abc9024b 100644
--- a/hw/core/cpu-common.c
+++ b/hw/core/cpu-common.c
@@ -67,19 +67,9 @@ CPUState *cpu_create(const char *typename)
return cpu;
}
-/* Resetting the IRQ comes from across the code base so we take the
- * BQL here if we need to. cpu_interrupt assumes it is held.*/
void cpu_reset_interrupt(CPUState *cpu, int mask)
{
- bool need_lock = !bql_locked();
-
- if (need_lock) {
- bql_lock();
- }
- cpu->interrupt_request &= ~mask;
- if (need_lock) {
- bql_unlock();
- }
+ qatomic_and(&cpu->interrupt_request, ~mask);
}
void cpu_exit(CPUState *cpu)
diff --git a/system/cpus.c b/system/cpus.c
index 437848b5eb4..9bfbe2b0607 100644
--- a/system/cpus.c
+++ b/system/cpus.c
@@ -257,8 +257,7 @@ int64_t cpus_get_elapsed_ticks(void)
void cpu_set_interrupt(CPUState *cpu, int mask)
{
/* Pairs with cpu_test_interrupt(). */
- qatomic_store_release(&cpu->interrupt_request,
- cpu->interrupt_request | mask);
+ qatomic_or(&cpu->interrupt_request, mask);
}
void generic_handle_interrupt(CPUState *cpu, int mask)
--
2.51.0
