From: Paolo Bonzini <pbonzini@redhat.com>
To: qemu-devel@nongnu.org
Cc: Igor Mammedov <imammedo@redhat.com>
Subject: [PATCH 19/19] tcg/user: do not set exit_request gratuitously
Date: Mon, 8 Sep 2025 12:12:41 +0200 [thread overview]
Message-ID: <20250908101241.2110068-20-pbonzini@redhat.com> (raw)
In-Reply-To: <20250908101241.2110068-1-pbonzini@redhat.com>
Whenever user-mode emulation needs to go all the way out of the cpu
exec loop, it uses cpu_exit(), which already sets cpu->exit_request.
Therefore, there is no need for tcg_kick_vcpu_thread() to set
cpu->exit_request again outside system emulation.
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
accel/tcg/cpu-exec.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/accel/tcg/cpu-exec.c b/accel/tcg/cpu-exec.c
index ad94f96b252..7c20d9db122 100644
--- a/accel/tcg/cpu-exec.c
+++ b/accel/tcg/cpu-exec.c
@@ -751,6 +751,7 @@ static inline bool cpu_handle_exception(CPUState *cpu, int *ret)
void tcg_kick_vcpu_thread(CPUState *cpu)
{
+#ifndef CONFIG_USER_ONLY
/*
* Ensure cpu_exec will see the reason why the exit request was set.
* FIXME: this is not always needed. Other accelerators instead
@@ -758,6 +759,7 @@ void tcg_kick_vcpu_thread(CPUState *cpu)
* CPU thread; see kvm_arch_pre_run() for example.
*/
qatomic_store_release(&cpu->exit_request, true);
+#endif
/* Ensure cpu_exec will see the exit request after TCG has exited. */
qatomic_store_release(&cpu->neg.icount_decr.u16.high, -1);
--
2.51.0
prev parent reply other threads:[~2025-09-08 10:16 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-09-08 10:12 [PATCH v3 00/19] accel, cpus: clean up cpu->exit_request Paolo Bonzini
2025-09-08 10:12 ` [PATCH 01/19] target/ppc: limit cpu_interrupt_exittb to system emulation Paolo Bonzini
2025-09-08 10:12 ` [PATCH 02/19] target/sparc: limit cpu_check_irqs " Paolo Bonzini
2025-09-08 10:12 ` [PATCH 03/19] target/i386: limit a20 " Paolo Bonzini
2025-09-08 10:12 ` [PATCH 04/19] target-arm: remove uses of cpu_interrupt() for user-mode emulation Paolo Bonzini
2025-09-08 10:12 ` [PATCH 05/19] user-exec: remove cpu_interrupt() stub Paolo Bonzini
2025-09-08 10:12 ` [PATCH 06/19] treewide: clear bits of cs->interrupt_request with cpu_reset_interrupt() Paolo Bonzini
2025-09-08 10:12 ` [PATCH 07/19] cpu-common: use atomic access for interrupt_request Paolo Bonzini
2025-09-08 10:12 ` [PATCH 08/19] cpus: document that qemu_cpu_kick() can be used for BQL-less operation Paolo Bonzini
2025-09-08 10:12 ` [PATCH 09/19] accel: use store_release/load_acquire for cross-thread exit_request Paolo Bonzini
2025-09-08 10:12 ` [PATCH 10/19] accel: use atomic accesses for exit_request Paolo Bonzini
2025-09-08 10:12 ` [PATCH 11/19] accel/tcg: create a thread-kick function for TCG Paolo Bonzini
2025-09-08 10:12 ` [PATCH 12/19] accel/tcg: inline cpu_exit() Paolo Bonzini
2025-09-08 10:12 ` [PATCH 13/19] cpus: remove TCG-ism from cpu_exit() Paolo Bonzini
2025-09-08 10:12 ` [PATCH 14/19] cpus: properly kick CPUs out of inner execution loop Paolo Bonzini
2025-09-10 7:13 ` Richard Henderson
2025-09-08 10:12 ` [PATCH 15/19] treewide: rename qemu_wait_io_event/qemu_wait_io_event_common Paolo Bonzini
2025-09-10 7:14 ` Richard Henderson
2025-09-08 10:12 ` [PATCH 16/19] bsd-user, linux-user: introduce qemu_process_cpu_events Paolo Bonzini
2025-09-08 10:12 ` [PATCH 17/19] cpus: clear exit_request in qemu_process_cpu_events Paolo Bonzini
2025-09-08 10:12 ` [PATCH 18/19] accel: make all calls to qemu_process_cpu_events look the same Paolo Bonzini
2025-09-08 10:12 ` Paolo Bonzini [this message]
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