static struct kmem_cache *hv_page_cache;
+DEFINE_PER_CPU(int, hv_24x7_txn_flags);
+DEFINE_PER_CPU(int, hv_24x7_txn_err);
+
+struct hv_24x7_hw {
+ struct perf_event *events[255];
+};
+
+DEFINE_PER_CPU(struct hv_24x7_hw, hv_24x7_hw);
+
/*
* request_buffer and result_buffer are not required to be 4k aligned,
* but are not allowed to cross any 4k boundary. Aligning them to 4k is
static void h_24x7_event_read(struct perf_event *event)
{
u64 now;
+ struct hv_24x7_request_buffer *request_buffer;
+ struct hv_24x7_hw *h24x7hw;
+ int txn_flags;
+
+ txn_flags = __this_cpu_read(hv_24x7_txn_flags);
+
+ /*
+ * If in a READ transaction, add this counter to the list of
+ * counters to read during the next HCALL (i.e commit_txn()).
+ * If not in a READ transaction, go ahead and make the HCALL
+ * to read this counter by itself.
+ */
+
+ if (txn_flags & PERF_PMU_TXN_READ) {
+ int i;
+ int ret;
- now = h_24x7_get_value(event);
- update_event_count(event, now);
+ if (__this_cpu_read(hv_24x7_txn_err))
+ return;
+
+ request_buffer = (void *)get_cpu_var(hv_24x7_reqb);
+
+ ret = add_event_to_24x7_request(event, request_buffer);
+ if (ret) {
+ __this_cpu_write(hv_24x7_txn_err, ret);
+ } else {
+ /*
+ * Assoicate the event with the HCALL request index,
+ * so ->commit_txn() can quickly find/update count.
+ */
+ i = request_buffer->num_requests - 1;
+
+ h24x7hw = &get_cpu_var(hv_24x7_hw);
+ h24x7hw->events[i] = event;
+ put_cpu_var(h24x7hw);
+ }
+
+ put_cpu_var(hv_24x7_reqb);
+ } else {
+ now = h_24x7_get_value(event);
+ update_event_count(event, now);
+ }
}
static void h_24x7_event_start(struct perf_event *event, int flags)
return 0;
}
+/*
+ * 24x7 counters only support READ transactions. They are
+ * always counting and dont need/support ADD transactions.
+ * Cache the flags, but otherwise ignore transactions that
+ * are not PERF_PMU_TXN_READ.
+ */
+static void h_24x7_event_start_txn(struct pmu *pmu, unsigned int flags)
+{
+ struct hv_24x7_request_buffer *request_buffer;
+ struct hv_24x7_data_result_buffer *result_buffer;
+
+ /* We should not be called if we are already in a txn */
+ WARN_ON_ONCE(__this_cpu_read(hv_24x7_txn_flags));
+
+ __this_cpu_write(hv_24x7_txn_flags, flags);
+ if (flags & ~PERF_PMU_TXN_READ)
+ return;
+
+ request_buffer = (void *)get_cpu_var(hv_24x7_reqb);
+ result_buffer = (void *)get_cpu_var(hv_24x7_resb);
+
+ init_24x7_request(request_buffer, result_buffer);
+
+ put_cpu_var(hv_24x7_resb);
+ put_cpu_var(hv_24x7_reqb);
+}
+
+/*
+ * Clean up transaction state.
+ *
+ * NOTE: Ignore state of request and result buffers for now.
+ * We will initialize them during the next read/txn.
+ */
+static void reset_txn(void)
+{
+ __this_cpu_write(hv_24x7_txn_flags, 0);
+ __this_cpu_write(hv_24x7_txn_err, 0);
+}
+
+/*
+ * 24x7 counters only support READ transactions. They are always counting
+ * and dont need/support ADD transactions. Clear ->txn_flags but otherwise
+ * ignore transactions that are not of type PERF_PMU_TXN_READ.
+ *
+ * For READ transactions, submit all pending 24x7 requests (i.e requests
+ * that were queued by h_24x7_event_read()), to the hypervisor and update
+ * the event counts.
+ */
+static int h_24x7_event_commit_txn(struct pmu *pmu)
+{
+ struct hv_24x7_request_buffer *request_buffer;
+ struct hv_24x7_data_result_buffer *result_buffer;
+ struct hv_24x7_result *resb;
+ struct perf_event *event;
+ u64 count;
+ int i, ret, txn_flags;
+ struct hv_24x7_hw *h24x7hw;
+
+ txn_flags = __this_cpu_read(hv_24x7_txn_flags);
+ WARN_ON_ONCE(!txn_flags);
+
+ ret = 0;
+ if (txn_flags & ~PERF_PMU_TXN_READ)
+ goto out;
+
+ ret = __this_cpu_read(hv_24x7_txn_err);
+ if (ret)
+ goto out;
+
+ request_buffer = (void *)get_cpu_var(hv_24x7_reqb);
+ result_buffer = (void *)get_cpu_var(hv_24x7_resb);
+
+ ret = make_24x7_request(request_buffer, result_buffer);
+ if (ret) {
+ log_24x7_hcall(request_buffer, result_buffer, ret);
+ goto put_reqb;
+ }
+
+ h24x7hw = &get_cpu_var(hv_24x7_hw);
+
+ /* Update event counts from hcall */
+ for (i = 0; i < request_buffer->num_requests; i++) {
+ resb = &result_buffer->results[i];
+ count = be64_to_cpu(resb->elements[0].element_data[0]);
+ event = h24x7hw->events[i];
+ h24x7hw->events[i] = NULL;
+ update_event_count(event, count);
+ }
+
+ put_cpu_var(hv_24x7_hw);
+
+put_reqb:
+ put_cpu_var(hv_24x7_resb);
+ put_cpu_var(hv_24x7_reqb);
+out:
+ reset_txn();
+ return ret;
+}
+
+/*
+ * 24x7 counters only support READ transactions. They are always counting
+ * and dont need/support ADD transactions. However, regardless of type
+ * of transaction, all we need to do is cleanup, so we don't have to check
+ * the type of transaction.
+ */
+static void h_24x7_event_cancel_txn(struct pmu *pmu)
+{
+ WARN_ON_ONCE(!__this_cpu_read(hv_24x7_txn_flags));
+ reset_txn();
+}
+
static struct pmu h_24x7_pmu = {
.task_ctx_nr = perf_invalid_context,
.start = h_24x7_event_start,
.stop = h_24x7_event_stop,
.read = h_24x7_event_read,
+ .start_txn = h_24x7_event_start_txn,
+ .commit_txn = h_24x7_event_commit_txn,
+ .cancel_txn = h_24x7_event_cancel_txn,
};
static int hv_24x7_init(void)
projects / karo-tx-linux.git / blobdiff