[PATCH v5 1/5] target/riscv: Propagate error from PMU setup

[Rob Bradford]

More closely follow the QEMU style by returning an Error and propagating
it there is an error relating to the PMU setup.

Further simplify the function by removing the num_counters parameter as
this is available from the passed in cpu pointer.

Signed-off-by: Rob Bradford <rbradford@rivosinc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
---
 target/riscv/pmu.c         | 19 +++++++++----------
 target/riscv/pmu.h         |  3 ++-
 target/riscv/tcg/tcg-cpu.c |  8 +++++++-
 3 files changed, 18 insertions(+), 12 deletions(-)

diff --git a/target/riscv/pmu.c b/target/riscv/pmu.c
index 36f6307d28..13801ccb78 100644
--- a/target/riscv/pmu.c
+++ b/target/riscv/pmu.c
@@ -434,22 +434,21 @@ int riscv_pmu_setup_timer(CPURISCVState *env, uint64_t 
value, uint32_t ctr_idx)
 }
 
 
-int riscv_pmu_init(RISCVCPU *cpu, int num_counters)
+void riscv_pmu_init(RISCVCPU *cpu, Error **errp)
 {
-    if (num_counters > (RV_MAX_MHPMCOUNTERS - 3)) {
-        return -1;
+    uint8_t pmu_num = cpu->cfg.pmu_num;
+
+    if (pmu_num > (RV_MAX_MHPMCOUNTERS - 3)) {
+        error_setg(errp, "Number of counters exceeds maximum available");
+        return;
     }
 
     cpu->pmu_event_ctr_map = g_hash_table_new(g_direct_hash, g_direct_equal);
     if (!cpu->pmu_event_ctr_map) {
-        /* PMU support can not be enabled */
-        qemu_log_mask(LOG_UNIMP, "PMU events can't be supported\n");
-        cpu->cfg.pmu_num = 0;
-        return -1;
+        error_setg(errp, "Unable to allocate PMU event hash table");
+        return;
     }
 
     /* Create a bitmask of available programmable counters */
-    cpu->pmu_avail_ctrs = MAKE_32BIT_MASK(3, num_counters);
-
-    return 0;
+    cpu->pmu_avail_ctrs = MAKE_32BIT_MASK(3, pmu_num);
 }
diff --git a/target/riscv/pmu.h b/target/riscv/pmu.h
index 2bfb71ba87..88e0713296 100644
--- a/target/riscv/pmu.h
+++ b/target/riscv/pmu.h
@@ -17,13 +17,14 @@
  */
 
 #include "cpu.h"
+#include "qapi/error.h"
 
 bool riscv_pmu_ctr_monitor_instructions(CPURISCVState *env,
                                         uint32_t target_ctr);
 bool riscv_pmu_ctr_monitor_cycles(CPURISCVState *env,
                                   uint32_t target_ctr);
 void riscv_pmu_timer_cb(void *priv);
-int riscv_pmu_init(RISCVCPU *cpu, int num_counters);
+void riscv_pmu_init(RISCVCPU *cpu, Error **errp);
 int riscv_pmu_update_event_map(CPURISCVState *env, uint64_t value,
                                uint32_t ctr_idx);
 int riscv_pmu_incr_ctr(RISCVCPU *cpu, enum riscv_pmu_event_idx event_idx);
diff --git a/target/riscv/tcg/tcg-cpu.c b/target/riscv/tcg/tcg-cpu.c
index a28918ab30..ed3eb991c0 100644
--- a/target/riscv/tcg/tcg-cpu.c
+++ b/target/riscv/tcg/tcg-cpu.c
@@ -614,7 +614,13 @@ static bool tcg_cpu_realize(CPUState *cs, Error **errp)
     }
 
     if (cpu->cfg.pmu_num) {
-        if (!riscv_pmu_init(cpu, cpu->cfg.pmu_num) && cpu->cfg.ext_sscofpmf) {
+        riscv_pmu_init(cpu, &local_err);
+        if (local_err != NULL) {
+            error_propagate(errp, local_err);
+            return false;
+        }
+
+        if (cpu->cfg.ext_sscofpmf) {
             cpu->pmu_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
                                           riscv_pmu_timer_cb, cpu);
         }
-- 
2.41.0