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From: Robert Foley <robert.foley@linaro.org>
To: qemu-devel@nongnu.org
Cc: richard.henderson@linaro.org, "Emilio G. Cota" <cota@braap.org>,
	alex.bennee@linaro.org, robert.foley@linaro.org,
	peter.puhov@linaro.org
Subject: [PATCH v8 63/74] cpu: introduce cpu_has_work_with_iothread_lock
Date: Thu, 26 Mar 2020 15:31:45 -0400
Message-ID: <20200326193156.4322-64-robert.foley@linaro.org> (raw)
In-Reply-To: <20200326193156.4322-1-robert.foley@linaro.org>

From: "Emilio G. Cota" <cota@braap.org>

It will gain some users soon.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Robert Foley <robert.foley@linaro.org>
---
 include/hw/core/cpu.h | 37 ++++++++++++++++++++++++++++++++++---
 1 file changed, 34 insertions(+), 3 deletions(-)

diff --git a/include/hw/core/cpu.h b/include/hw/core/cpu.h
index a01c258320..e3527b6194 100644
--- a/include/hw/core/cpu.h
+++ b/include/hw/core/cpu.h
@@ -26,6 +26,7 @@
 #include "exec/memattrs.h"
 #include "qapi/qapi-types-run-state.h"
 #include "qemu/bitmap.h"
+#include "qemu/main-loop.h"
 #include "qemu/rcu_queue.h"
 #include "qemu/queue.h"
 #include "qemu/thread.h"
@@ -82,6 +83,8 @@ struct TranslationBlock;
  * @reset_dump_flags: #CPUDumpFlags to use for reset logging.
  * @has_work: Callback for checking if there is work to do. Called with the
  * CPU lock held.
+ * @has_work_with_iothread_lock: Callback for checking if there is work to do.
+ * Called with both the BQL and the CPU lock held.
  * @do_interrupt: Callback for interrupt handling.
  * @do_unaligned_access: Callback for unaligned access handling, if
  * the target defines #TARGET_ALIGNED_ONLY.
@@ -167,6 +170,7 @@ typedef struct CPUClass {
 
     int reset_dump_flags;
     bool (*has_work)(CPUState *cpu);
+    bool (*has_work_with_iothread_lock)(CPUState *cpu);
     void (*do_interrupt)(CPUState *cpu);
     void (*do_unaligned_access)(CPUState *cpu, vaddr addr,
                                 MMUAccessType access_type,
@@ -800,14 +804,41 @@ const char *parse_cpu_option(const char *cpu_option);
 static inline bool cpu_has_work(CPUState *cpu)
 {
     CPUClass *cc = CPU_GET_CLASS(cpu);
+    bool has_cpu_lock = cpu_mutex_locked(cpu);
+    bool (*func)(CPUState *cpu);
     bool ret;
 
+    /* some targets require us to hold the BQL when checking for work */
+    if (cc->has_work_with_iothread_lock) {
+        if (qemu_mutex_iothread_locked()) {
+            func = cc->has_work_with_iothread_lock;
+            goto call_func;
+        }
+
+        if (has_cpu_lock) {
+            /* avoid deadlock by acquiring the locks in order */
+            cpu_mutex_unlock(cpu);
+        }
+        qemu_mutex_lock_iothread();
+        cpu_mutex_lock(cpu);
+
+        ret = cc->has_work_with_iothread_lock(cpu);
+
+        qemu_mutex_unlock_iothread();
+        if (!has_cpu_lock) {
+            cpu_mutex_unlock(cpu);
+        }
+        return ret;
+    }
+
     g_assert(cc->has_work);
-    if (cpu_mutex_locked(cpu)) {
-        return cc->has_work(cpu);
+    func = cc->has_work;
+ call_func:
+    if (has_cpu_lock) {
+        return func(cpu);
     }
     cpu_mutex_lock(cpu);
-    ret = cc->has_work(cpu);
+    ret = func(cpu);
     cpu_mutex_unlock(cpu);
     return ret;
 }
-- 
2.17.1



  parent reply index

Thread overview: 100+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-26 19:30 [PATCH v8 00/74] per-CPU locks Robert Foley
2020-03-26 19:30 ` [PATCH v8 01/74] cpu: convert queued work to a QSIMPLEQ Robert Foley
2020-03-26 19:30 ` [PATCH v8 02/74] cpu: rename cpu->work_mutex to cpu->lock Robert Foley
2020-05-11 14:48   ` Alex Bennée
2020-05-11 16:33     ` Robert Foley
2020-03-26 19:30 ` [PATCH v8 03/74] cpu: introduce cpu_mutex_lock/unlock Robert Foley
2020-05-11 10:24   ` Alex Bennée
2020-05-11 16:09     ` Robert Foley
2020-03-26 19:30 ` [PATCH v8 04/74] cpu: make qemu_work_cond per-cpu Robert Foley
2020-03-26 19:30 ` [PATCH v8 05/74] cpu: move run_on_cpu to cpus-common Robert Foley
2020-03-26 19:30 ` [PATCH v8 06/74] cpu: introduce process_queued_cpu_work_locked Robert Foley
2020-03-26 19:30 ` [PATCH v8 07/74] cpu: make per-CPU locks an alias of the BQL in TCG rr mode Robert Foley
2020-03-26 19:30 ` [PATCH v8 08/74] tcg-runtime: define helper_cpu_halted_set Robert Foley
2020-03-26 19:30 ` [PATCH v8 09/74] ppc: convert to helper_cpu_halted_set Robert Foley
2020-03-26 19:30 ` [PATCH v8 10/74] cris: " Robert Foley
2020-03-26 19:30 ` [PATCH v8 11/74] hppa: " Robert Foley
2020-03-26 19:30 ` [PATCH v8 12/74] m68k: " Robert Foley
2020-03-26 19:30 ` [PATCH v8 13/74] alpha: " Robert Foley
2020-03-26 19:30 ` [PATCH v8 14/74] microblaze: " Robert Foley
2020-03-26 19:30 ` [PATCH v8 15/74] cpu: define cpu_halted helpers Robert Foley
2020-03-26 19:30 ` [PATCH v8 16/74] tcg-runtime: convert to cpu_halted_set Robert Foley
2020-03-26 19:30 ` [PATCH v8 17/74] hw/semihosting: " Robert Foley
2020-05-11 10:25   ` Alex Bennée
2020-03-26 19:31 ` [PATCH v8 18/74] arm: convert to cpu_halted Robert Foley
2020-03-26 19:31 ` [PATCH v8 19/74] ppc: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 20/74] sh4: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 21/74] i386: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 22/74] lm32: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 23/74] m68k: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 24/74] mips: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 25/74] riscv: " Robert Foley
2020-05-11 10:40   ` Alex Bennée
2020-05-11 16:13     ` Robert Foley
2020-03-26 19:31 ` [PATCH v8 26/74] s390x: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 27/74] sparc: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 28/74] xtensa: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 29/74] gdbstub: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 30/74] openrisc: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 31/74] cpu-exec: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 32/74] cpu: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 33/74] cpu: define cpu_interrupt_request helpers Robert Foley
2020-03-26 19:31 ` [PATCH v8 34/74] ppc: use cpu_reset_interrupt Robert Foley
2020-03-26 19:31 ` [PATCH v8 35/74] exec: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 36/74] i386: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 37/74] s390x: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 38/74] openrisc: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 39/74] arm: convert to cpu_interrupt_request Robert Foley
2020-03-26 19:31 ` [PATCH v8 40/74] i386: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 41/74] i386/kvm: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 42/74] i386/hax-all: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 43/74] i386/whpx-all: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 44/74] i386/hvf: convert to cpu_request_interrupt Robert Foley
2020-03-26 19:31 ` [PATCH v8 45/74] ppc: convert to cpu_interrupt_request Robert Foley
2020-03-26 19:31 ` [PATCH v8 46/74] sh4: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 47/74] cris: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 48/74] hppa: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 49/74] lm32: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 50/74] m68k: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 51/74] mips: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 52/74] nios: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 53/74] s390x: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 54/74] alpha: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 55/74] moxie: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 56/74] sparc: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 57/74] openrisc: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 58/74] unicore32: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 59/74] microblaze: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 60/74] accel/tcg: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 61/74] cpu: convert to interrupt_request Robert Foley
2020-03-26 19:31 ` [PATCH v8 62/74] cpu: call .cpu_has_work with the CPU lock held Robert Foley
2020-03-26 19:31 ` Robert Foley [this message]
2020-03-26 19:31 ` [PATCH v8 64/74] ppc: convert to cpu_has_work_with_iothread_lock Robert Foley
2020-03-26 19:31 ` [PATCH v8 65/74] mips: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 66/74] s390x: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 67/74] riscv: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 68/74] sparc: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 69/74] xtensa: " Robert Foley
2020-03-26 19:31 ` [PATCH v8 70/74] cpu: rename all_cpu_threads_idle to qemu_tcg_rr_all_cpu_threads_idle Robert Foley
2020-03-26 19:31 ` [PATCH v8 71/74] cpu: protect CPU state with cpu->lock instead of the BQL Robert Foley
2020-03-26 19:31 ` [PATCH v8 72/74] cpus-common: release BQL earlier in run_on_cpu Robert Foley
2020-03-26 19:31 ` [PATCH v8 73/74] cpu: add async_run_on_cpu_no_bql Robert Foley
2020-03-26 19:31 ` [PATCH v8 74/74] cputlb: queue async flush jobs without the BQL Robert Foley
2020-05-12 16:27   ` Alex Bennée
2020-05-12 19:26     ` Robert Foley
2020-05-18 13:46       ` Robert Foley
2020-05-20  4:46         ` Emilio G. Cota
2020-05-20 15:01           ` Robert Foley
2020-05-21 14:17             ` Robert Foley
2020-05-12 18:38   ` Alex Bennée
2020-03-26 22:58 ` [PATCH v8 00/74] per-CPU locks Aleksandar Markovic
2020-03-27  9:39   ` Alex Bennée
2020-03-27  9:50     ` Aleksandar Markovic
2020-03-27 10:24       ` Aleksandar Markovic
2020-03-27 17:21         ` Robert Foley
2020-03-27  5:14 ` Emilio G. Cota
2020-03-27 10:59   ` Philippe Mathieu-Daudé
2020-03-30  8:57     ` Stefan Hajnoczi
2020-03-27 18:23   ` Alex Bennée
2020-03-27 18:30   ` Robert Foley
2020-05-12 16:29 ` Alex Bennée

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