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@@ -0,0 +1,1641 @@
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+/*
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+ * Performance event support for the System z CPU-measurement Sampling Facility
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+ *
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+ * Copyright IBM Corp. 2013
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+ * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
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+ *
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+ * This program is free software; you can redistribute it and/or modify
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+ * it under the terms of the GNU General Public License (version 2 only)
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+ * as published by the Free Software Foundation.
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+ */
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+#define KMSG_COMPONENT "cpum_sf"
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+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
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+
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+#include <linux/kernel.h>
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+#include <linux/kernel_stat.h>
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+#include <linux/perf_event.h>
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+#include <linux/percpu.h>
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+#include <linux/notifier.h>
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+#include <linux/export.h>
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+#include <linux/slab.h>
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+#include <linux/mm.h>
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+#include <linux/moduleparam.h>
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+#include <asm/cpu_mf.h>
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+#include <asm/irq.h>
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+#include <asm/debug.h>
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+#include <asm/timex.h>
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+
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+/* Minimum number of sample-data-block-tables:
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+ * At least one table is required for the sampling buffer structure.
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+ * A single table contains up to 511 pointers to sample-data-blocks.
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+ */
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+#define CPUM_SF_MIN_SDBT 1
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+
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+/* Number of sample-data-blocks per sample-data-block-table (SDBT):
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+ * A table contains SDB pointers (8 bytes) and one table-link entry
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+ * that points to the origin of the next SDBT.
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+ */
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+#define CPUM_SF_SDB_PER_TABLE ((PAGE_SIZE - 8) / 8)
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+
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+/* Maximum page offset for an SDBT table-link entry:
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+ * If this page offset is reached, a table-link entry to the next SDBT
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+ * must be added.
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+ */
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+#define CPUM_SF_SDBT_TL_OFFSET (CPUM_SF_SDB_PER_TABLE * 8)
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+static inline int require_table_link(const void *sdbt)
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+{
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+ return ((unsigned long) sdbt & ~PAGE_MASK) == CPUM_SF_SDBT_TL_OFFSET;
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+}
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+
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+/* Minimum and maximum sampling buffer sizes:
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+ *
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+ * This number represents the maximum size of the sampling buffer taking
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+ * the number of sample-data-block-tables into account. Note that these
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+ * numbers apply to the basic-sampling function only.
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+ * The maximum number of SDBs is increased by CPUM_SF_SDB_DIAG_FACTOR if
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+ * the diagnostic-sampling function is active.
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+ *
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+ * Sampling buffer size Buffer characteristics
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+ * ---------------------------------------------------
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+ * 64KB == 16 pages (4KB per page)
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+ * 1 page for SDB-tables
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+ * 15 pages for SDBs
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+ *
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+ * 32MB == 8192 pages (4KB per page)
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+ * 16 pages for SDB-tables
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+ * 8176 pages for SDBs
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+ */
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+static unsigned long __read_mostly CPUM_SF_MIN_SDB = 15;
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+static unsigned long __read_mostly CPUM_SF_MAX_SDB = 8176;
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+static unsigned long __read_mostly CPUM_SF_SDB_DIAG_FACTOR = 1;
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+
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+struct sf_buffer {
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+ unsigned long *sdbt; /* Sample-data-block-table origin */
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+ /* buffer characteristics (required for buffer increments) */
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+ unsigned long num_sdb; /* Number of sample-data-blocks */
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+ unsigned long num_sdbt; /* Number of sample-data-block-tables */
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+ unsigned long *tail; /* last sample-data-block-table */
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+};
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+
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+struct cpu_hw_sf {
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+ /* CPU-measurement sampling information block */
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+ struct hws_qsi_info_block qsi;
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+ /* CPU-measurement sampling control block */
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+ struct hws_lsctl_request_block lsctl;
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+ struct sf_buffer sfb; /* Sampling buffer */
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+ unsigned int flags; /* Status flags */
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+ struct perf_event *event; /* Scheduled perf event */
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+};
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+static DEFINE_PER_CPU(struct cpu_hw_sf, cpu_hw_sf);
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+
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+/* Debug feature */
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+static debug_info_t *sfdbg;
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+
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+/*
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+ * sf_disable() - Switch off sampling facility
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+ */
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+static int sf_disable(void)
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+{
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+ struct hws_lsctl_request_block sreq;
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+
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+ memset(&sreq, 0, sizeof(sreq));
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+ return lsctl(&sreq);
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+}
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+
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+/*
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+ * sf_buffer_available() - Check for an allocated sampling buffer
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+ */
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+static int sf_buffer_available(struct cpu_hw_sf *cpuhw)
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+{
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+ return !!cpuhw->sfb.sdbt;
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+}
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+
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+/*
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+ * deallocate sampling facility buffer
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+ */
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+static void free_sampling_buffer(struct sf_buffer *sfb)
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+{
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+ unsigned long *sdbt, *curr;
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+
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+ if (!sfb->sdbt)
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+ return;
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+
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+ sdbt = sfb->sdbt;
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+ curr = sdbt;
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+
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+ /* Free the SDBT after all SDBs are processed... */
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+ while (1) {
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+ if (!*curr || !sdbt)
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+ break;
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+
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+ /* Process table-link entries */
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+ if (is_link_entry(curr)) {
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+ curr = get_next_sdbt(curr);
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+ if (sdbt)
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+ free_page((unsigned long) sdbt);
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+
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+ /* If the origin is reached, sampling buffer is freed */
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+ if (curr == sfb->sdbt)
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+ break;
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+ else
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+ sdbt = curr;
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+ } else {
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+ /* Process SDB pointer */
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+ if (*curr) {
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+ free_page(*curr);
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+ curr++;
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+ }
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+ }
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+ }
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+
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+ debug_sprintf_event(sfdbg, 5,
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+ "free_sampling_buffer: freed sdbt=%p\n", sfb->sdbt);
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+ memset(sfb, 0, sizeof(*sfb));
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+}
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+
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+static int alloc_sample_data_block(unsigned long *sdbt, gfp_t gfp_flags)
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+{
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+ unsigned long sdb, *trailer;
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+
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+ /* Allocate and initialize sample-data-block */
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+ sdb = get_zeroed_page(gfp_flags);
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+ if (!sdb)
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+ return -ENOMEM;
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+ trailer = trailer_entry_ptr(sdb);
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+ *trailer = SDB_TE_ALERT_REQ_MASK;
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+
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+ /* Link SDB into the sample-data-block-table */
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+ *sdbt = sdb;
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+
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+ return 0;
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+}
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+
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+/*
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+ * realloc_sampling_buffer() - extend sampler memory
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+ *
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+ * Allocates new sample-data-blocks and adds them to the specified sampling
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+ * buffer memory.
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+ *
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+ * Important: This modifies the sampling buffer and must be called when the
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+ * sampling facility is disabled.
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+ *
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+ * Returns zero on success, non-zero otherwise.
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+ */
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+static int realloc_sampling_buffer(struct sf_buffer *sfb,
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+ unsigned long num_sdb, gfp_t gfp_flags)
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+{
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+ int i, rc;
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+ unsigned long *new, *tail;
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+
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+ if (!sfb->sdbt || !sfb->tail)
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+ return -EINVAL;
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+
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+ if (!is_link_entry(sfb->tail))
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+ return -EINVAL;
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+
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+ /* Append to the existing sampling buffer, overwriting the table-link
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+ * register.
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+ * The tail variables always points to the "tail" (last and table-link)
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+ * entry in an SDB-table.
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+ */
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+ tail = sfb->tail;
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+
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+ /* Do a sanity check whether the table-link entry points to
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+ * the sampling buffer origin.
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+ */
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+ if (sfb->sdbt != get_next_sdbt(tail)) {
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+ debug_sprintf_event(sfdbg, 3, "realloc_sampling_buffer: "
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+ "sampling buffer is not linked: origin=%p"
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+ "tail=%p\n",
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+ (void *) sfb->sdbt, (void *) tail);
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+ return -EINVAL;
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+ }
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+
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+ /* Allocate remaining SDBs */
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+ rc = 0;
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+ for (i = 0; i < num_sdb; i++) {
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+ /* Allocate a new SDB-table if it is full. */
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+ if (require_table_link(tail)) {
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+ new = (unsigned long *) get_zeroed_page(gfp_flags);
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+ if (!new) {
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+ rc = -ENOMEM;
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+ break;
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+ }
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+ sfb->num_sdbt++;
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+ /* Link current page to tail of chain */
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+ *tail = (unsigned long)(void *) new + 1;
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+ tail = new;
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+ }
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+
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+ /* Allocate a new sample-data-block.
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+ * If there is not enough memory, stop the realloc process
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+ * and simply use what was allocated. If this is a temporary
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+ * issue, a new realloc call (if required) might succeed.
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+ */
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+ rc = alloc_sample_data_block(tail, gfp_flags);
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+ if (rc)
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+ break;
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+ sfb->num_sdb++;
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+ tail++;
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+ }
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+
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+ /* Link sampling buffer to its origin */
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+ *tail = (unsigned long) sfb->sdbt + 1;
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+ sfb->tail = tail;
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+
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+ debug_sprintf_event(sfdbg, 4, "realloc_sampling_buffer: new buffer"
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+ " settings: sdbt=%lu sdb=%lu\n",
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+ sfb->num_sdbt, sfb->num_sdb);
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+ return rc;
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+}
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+
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+/*
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+ * allocate_sampling_buffer() - allocate sampler memory
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+ *
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+ * Allocates and initializes a sampling buffer structure using the
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+ * specified number of sample-data-blocks (SDB). For each allocation,
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+ * a 4K page is used. The number of sample-data-block-tables (SDBT)
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+ * are calculated from SDBs.
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+ * Also set the ALERT_REQ mask in each SDBs trailer.
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+ *
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+ * Returns zero on success, non-zero otherwise.
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+ */
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+static int alloc_sampling_buffer(struct sf_buffer *sfb, unsigned long num_sdb)
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+{
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+ int rc;
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+
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+ if (sfb->sdbt)
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+ return -EINVAL;
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+
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+ /* Allocate the sample-data-block-table origin */
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+ sfb->sdbt = (unsigned long *) get_zeroed_page(GFP_KERNEL);
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+ if (!sfb->sdbt)
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+ return -ENOMEM;
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+ sfb->num_sdb = 0;
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+ sfb->num_sdbt = 1;
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+
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+ /* Link the table origin to point to itself to prepare for
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+ * realloc_sampling_buffer() invocation.
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+ */
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+ sfb->tail = sfb->sdbt;
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+ *sfb->tail = (unsigned long)(void *) sfb->sdbt + 1;
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+
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+ /* Allocate requested number of sample-data-blocks */
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+ rc = realloc_sampling_buffer(sfb, num_sdb, GFP_KERNEL);
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+ if (rc) {
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+ free_sampling_buffer(sfb);
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+ debug_sprintf_event(sfdbg, 4, "alloc_sampling_buffer: "
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+ "realloc_sampling_buffer failed with rc=%i\n", rc);
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+ } else
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+ debug_sprintf_event(sfdbg, 4,
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+ "alloc_sampling_buffer: tear=%p dear=%p\n",
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+ sfb->sdbt, (void *) *sfb->sdbt);
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+ return rc;
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+}
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+
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+static void sfb_set_limits(unsigned long min, unsigned long max)
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+{
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+ struct hws_qsi_info_block si;
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+
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+ CPUM_SF_MIN_SDB = min;
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+ CPUM_SF_MAX_SDB = max;
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+
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+ memset(&si, 0, sizeof(si));
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+ if (!qsi(&si))
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+ CPUM_SF_SDB_DIAG_FACTOR = DIV_ROUND_UP(si.dsdes, si.bsdes);
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+}
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+
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+static unsigned long sfb_max_limit(struct hw_perf_event *hwc)
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+{
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+ return SAMPL_DIAG_MODE(hwc) ? CPUM_SF_MAX_SDB * CPUM_SF_SDB_DIAG_FACTOR
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+ : CPUM_SF_MAX_SDB;
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+}
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+
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+static unsigned long sfb_pending_allocs(struct sf_buffer *sfb,
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+ struct hw_perf_event *hwc)
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+{
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+ if (!sfb->sdbt)
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+ return SFB_ALLOC_REG(hwc);
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+ if (SFB_ALLOC_REG(hwc) > sfb->num_sdb)
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+ return SFB_ALLOC_REG(hwc) - sfb->num_sdb;
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+ return 0;
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+}
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+
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+static int sfb_has_pending_allocs(struct sf_buffer *sfb,
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+ struct hw_perf_event *hwc)
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+{
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+ return sfb_pending_allocs(sfb, hwc) > 0;
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+}
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+
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+static void sfb_account_allocs(unsigned long num, struct hw_perf_event *hwc)
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+{
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+ /* Limit the number of SDBs to not exceed the maximum */
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+ num = min_t(unsigned long, num, sfb_max_limit(hwc) - SFB_ALLOC_REG(hwc));
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+ if (num)
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+ SFB_ALLOC_REG(hwc) += num;
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+}
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+
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+static void sfb_init_allocs(unsigned long num, struct hw_perf_event *hwc)
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+{
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+ SFB_ALLOC_REG(hwc) = 0;
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+ sfb_account_allocs(num, hwc);
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+}
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+
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+static size_t event_sample_size(struct hw_perf_event *hwc)
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+{
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+ struct sf_raw_sample *sfr = (struct sf_raw_sample *) RAWSAMPLE_REG(hwc);
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+ size_t sample_size;
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+
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+ /* The sample size depends on the sampling function: The basic-sampling
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+ * function must be always enabled, diagnostic-sampling function is
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+ * optional.
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+ */
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+ sample_size = sfr->bsdes;
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+ if (SAMPL_DIAG_MODE(hwc))
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+ sample_size += sfr->dsdes;
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+
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+ return sample_size;
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+}
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+
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+static void deallocate_buffers(struct cpu_hw_sf *cpuhw)
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+{
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+ if (cpuhw->sfb.sdbt)
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+ free_sampling_buffer(&cpuhw->sfb);
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+}
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+
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+static int allocate_buffers(struct cpu_hw_sf *cpuhw, struct hw_perf_event *hwc)
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+{
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+ unsigned long n_sdb, freq, factor;
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+ size_t sfr_size, sample_size;
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+ struct sf_raw_sample *sfr;
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+
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+ /* Allocate raw sample buffer
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+ *
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+ * The raw sample buffer is used to temporarily store sampling data
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+ * entries for perf raw sample processing. The buffer size mainly
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+ * depends on the size of diagnostic-sampling data entries which is
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+ * machine-specific. The exact size calculation includes:
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+ * 1. The first 4 bytes of diagnostic-sampling data entries are
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+ * already reflected in the sf_raw_sample structure. Subtract
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+ * these bytes.
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+ * 2. The perf raw sample data must be 8-byte aligned (u64) and
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+ * perf's internal data size must be considered too. So add
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+ * an additional u32 for correct alignment and subtract before
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+ * allocating the buffer.
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+ * 3. Store the raw sample buffer pointer in the perf event
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+ * hardware structure.
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+ */
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+ sfr_size = ALIGN((sizeof(*sfr) - sizeof(sfr->diag) + cpuhw->qsi.dsdes) +
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+ sizeof(u32), sizeof(u64));
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+ sfr_size -= sizeof(u32);
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+ sfr = kzalloc(sfr_size, GFP_KERNEL);
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+ if (!sfr)
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+ return -ENOMEM;
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+ sfr->size = sfr_size;
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+ sfr->bsdes = cpuhw->qsi.bsdes;
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+ sfr->dsdes = cpuhw->qsi.dsdes;
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+ RAWSAMPLE_REG(hwc) = (unsigned long) sfr;
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+
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+ /* Calculate sampling buffers using 4K pages
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+ *
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+ * 1. Determine the sample data size which depends on the used
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|
|
+ * sampling functions, for example, basic-sampling or
|
|
|
+ * basic-sampling with diagnostic-sampling.
|
|
|
+ *
|
|
|
+ * 2. Use the sampling frequency as input. The sampling buffer is
|
|
|
+ * designed for almost one second. This can be adjusted through
|
|
|
+ * the "factor" variable.
|
|
|
+ * In any case, alloc_sampling_buffer() sets the Alert Request
|
|
|
+ * Control indicator to trigger a measurement-alert to harvest
|
|
|
+ * sample-data-blocks (sdb).
|
|
|
+ *
|
|
|
+ * 3. Compute the number of sample-data-blocks and ensure a minimum
|
|
|
+ * of CPUM_SF_MIN_SDB. Also ensure the upper limit does not
|
|
|
+ * exceed a "calculated" maximum. The symbolic maximum is
|
|
|
+ * designed for basic-sampling only and needs to be increased if
|
|
|
+ * diagnostic-sampling is active.
|
|
|
+ * See also the remarks for these symbolic constants.
|
|
|
+ *
|
|
|
+ * 4. Compute the number of sample-data-block-tables (SDBT) and
|
|
|
+ * ensure a minimum of CPUM_SF_MIN_SDBT (one table can manage up
|
|
|
+ * to 511 SDBs).
|
|
|
+ */
|
|
|
+ sample_size = event_sample_size(hwc);
|
|
|
+ freq = sample_rate_to_freq(&cpuhw->qsi, SAMPL_RATE(hwc));
|
|
|
+ factor = 1;
|
|
|
+ n_sdb = DIV_ROUND_UP(freq, factor * ((PAGE_SIZE-64) / sample_size));
|
|
|
+ if (n_sdb < CPUM_SF_MIN_SDB)
|
|
|
+ n_sdb = CPUM_SF_MIN_SDB;
|
|
|
+
|
|
|
+ /* If there is already a sampling buffer allocated, it is very likely
|
|
|
+ * that the sampling facility is enabled too. If the event to be
|
|
|
+ * initialized requires a greater sampling buffer, the allocation must
|
|
|
+ * be postponed. Changing the sampling buffer requires the sampling
|
|
|
+ * facility to be in the disabled state. So, account the number of
|
|
|
+ * required SDBs and let cpumsf_pmu_enable() resize the buffer just
|
|
|
+ * before the event is started.
|
|
|
+ */
|
|
|
+ sfb_init_allocs(n_sdb, hwc);
|
|
|
+ if (sf_buffer_available(cpuhw))
|
|
|
+ return 0;
|
|
|
+
|
|
|
+ debug_sprintf_event(sfdbg, 3,
|
|
|
+ "allocate_buffers: rate=%lu f=%lu sdb=%lu/%lu"
|
|
|
+ " sample_size=%lu cpuhw=%p\n",
|
|
|
+ SAMPL_RATE(hwc), freq, n_sdb, sfb_max_limit(hwc),
|
|
|
+ sample_size, cpuhw);
|
|
|
+
|
|
|
+ return alloc_sampling_buffer(&cpuhw->sfb,
|
|
|
+ sfb_pending_allocs(&cpuhw->sfb, hwc));
|
|
|
+}
|
|
|
+
|
|
|
+static unsigned long min_percent(unsigned int percent, unsigned long base,
|
|
|
+ unsigned long min)
|
|
|
+{
|
|
|
+ return min_t(unsigned long, min, DIV_ROUND_UP(percent * base, 100));
|
|
|
+}
|
|
|
+
|
|
|
+static unsigned long compute_sfb_extent(unsigned long ratio, unsigned long base)
|
|
|
+{
|
|
|
+ /* Use a percentage-based approach to extend the sampling facility
|
|
|
+ * buffer. Accept up to 5% sample data loss.
|
|
|
+ * Vary the extents between 1% to 5% of the current number of
|
|
|
+ * sample-data-blocks.
|
|
|
+ */
|
|
|
+ if (ratio <= 5)
|
|
|
+ return 0;
|
|
|
+ if (ratio <= 25)
|
|
|
+ return min_percent(1, base, 1);
|
|
|
+ if (ratio <= 50)
|
|
|
+ return min_percent(1, base, 1);
|
|
|
+ if (ratio <= 75)
|
|
|
+ return min_percent(2, base, 2);
|
|
|
+ if (ratio <= 100)
|
|
|
+ return min_percent(3, base, 3);
|
|
|
+ if (ratio <= 250)
|
|
|
+ return min_percent(4, base, 4);
|
|
|
+
|
|
|
+ return min_percent(5, base, 8);
|
|
|
+}
|
|
|
+
|
|
|
+static void sfb_account_overflows(struct cpu_hw_sf *cpuhw,
|
|
|
+ struct hw_perf_event *hwc)
|
|
|
+{
|
|
|
+ unsigned long ratio, num;
|
|
|
+
|
|
|
+ if (!OVERFLOW_REG(hwc))
|
|
|
+ return;
|
|
|
+
|
|
|
+ /* The sample_overflow contains the average number of sample data
|
|
|
+ * that has been lost because sample-data-blocks were full.
|
|
|
+ *
|
|
|
+ * Calculate the total number of sample data entries that has been
|
|
|
+ * discarded. Then calculate the ratio of lost samples to total samples
|
|
|
+ * per second in percent.
|
|
|
+ */
|
|
|
+ ratio = DIV_ROUND_UP(100 * OVERFLOW_REG(hwc) * cpuhw->sfb.num_sdb,
|
|
|
+ sample_rate_to_freq(&cpuhw->qsi, SAMPL_RATE(hwc)));
|
|
|
+
|
|
|
+ /* Compute number of sample-data-blocks */
|
|
|
+ num = compute_sfb_extent(ratio, cpuhw->sfb.num_sdb);
|
|
|
+ if (num)
|
|
|
+ sfb_account_allocs(num, hwc);
|
|
|
+
|
|
|
+ debug_sprintf_event(sfdbg, 5, "sfb: overflow: overflow=%llu ratio=%lu"
|
|
|
+ " num=%lu\n", OVERFLOW_REG(hwc), ratio, num);
|
|
|
+ OVERFLOW_REG(hwc) = 0;
|
|
|
+}
|
|
|
+
|
|
|
+/* extend_sampling_buffer() - Extend sampling buffer
|
|
|
+ * @sfb: Sampling buffer structure (for local CPU)
|
|
|
+ * @hwc: Perf event hardware structure
|
|
|
+ *
|
|
|
+ * Use this function to extend the sampling buffer based on the overflow counter
|
|
|
+ * and postponed allocation extents stored in the specified Perf event hardware.
|
|
|
+ *
|
|
|
+ * Important: This function disables the sampling facility in order to safely
|
|
|
+ * change the sampling buffer structure. Do not call this function
|
|
|
+ * when the PMU is active.
|
|
|
+ */
|
|
|
+static void extend_sampling_buffer(struct sf_buffer *sfb,
|
|
|
+ struct hw_perf_event *hwc)
|
|
|
+{
|
|
|
+ unsigned long num, num_old;
|
|
|
+ int rc;
|
|
|
+
|
|
|
+ num = sfb_pending_allocs(sfb, hwc);
|
|
|
+ if (!num)
|
|
|
+ return;
|
|
|
+ num_old = sfb->num_sdb;
|
|
|
+
|
|
|
+ /* Disable the sampling facility to reset any states and also
|
|
|
+ * clear pending measurement alerts.
|
|
|
+ */
|
|
|
+ sf_disable();
|
|
|
+
|
|
|
+ /* Extend the sampling buffer.
|
|
|
+ * This memory allocation typically happens in an atomic context when
|
|
|
+ * called by perf. Because this is a reallocation, it is fine if the
|
|
|
+ * new SDB-request cannot be satisfied immediately.
|
|
|
+ */
|
|
|
+ rc = realloc_sampling_buffer(sfb, num, GFP_ATOMIC);
|
|
|
+ if (rc)
|
|
|
+ debug_sprintf_event(sfdbg, 5, "sfb: extend: realloc "
|
|
|
+ "failed with rc=%i\n", rc);
|
|
|
+
|
|
|
+ if (sfb_has_pending_allocs(sfb, hwc))
|
|
|
+ debug_sprintf_event(sfdbg, 5, "sfb: extend: "
|
|
|
+ "req=%lu alloc=%lu remaining=%lu\n",
|
|
|
+ num, sfb->num_sdb - num_old,
|
|
|
+ sfb_pending_allocs(sfb, hwc));
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+/* Number of perf events counting hardware events */
|
|
|
+static atomic_t num_events;
|
|
|
+/* Used to avoid races in calling reserve/release_cpumf_hardware */
|
|
|
+static DEFINE_MUTEX(pmc_reserve_mutex);
|
|
|
+
|
|
|
+#define PMC_INIT 0
|
|
|
+#define PMC_RELEASE 1
|
|
|
+#define PMC_FAILURE 2
|
|
|
+static void setup_pmc_cpu(void *flags)
|
|
|
+{
|
|
|
+ int err;
|
|
|
+ struct cpu_hw_sf *cpusf = &__get_cpu_var(cpu_hw_sf);
|
|
|
+
|
|
|
+ err = 0;
|
|
|
+ switch (*((int *) flags)) {
|
|
|
+ case PMC_INIT:
|
|
|
+ memset(cpusf, 0, sizeof(*cpusf));
|
|
|
+ err = qsi(&cpusf->qsi);
|
|
|
+ if (err)
|
|
|
+ break;
|
|
|
+ cpusf->flags |= PMU_F_RESERVED;
|
|
|
+ err = sf_disable();
|
|
|
+ if (err)
|
|
|
+ pr_err("Switching off the sampling facility failed "
|
|
|
+ "with rc=%i\n", err);
|
|
|
+ debug_sprintf_event(sfdbg, 5,
|
|
|
+ "setup_pmc_cpu: initialized: cpuhw=%p\n", cpusf);
|
|
|
+ break;
|
|
|
+ case PMC_RELEASE:
|
|
|
+ cpusf->flags &= ~PMU_F_RESERVED;
|
|
|
+ err = sf_disable();
|
|
|
+ if (err) {
|
|
|
+ pr_err("Switching off the sampling facility failed "
|
|
|
+ "with rc=%i\n", err);
|
|
|
+ } else
|
|
|
+ deallocate_buffers(cpusf);
|
|
|
+ debug_sprintf_event(sfdbg, 5,
|
|
|
+ "setup_pmc_cpu: released: cpuhw=%p\n", cpusf);
|
|
|
+ break;
|
|
|
+ }
|
|
|
+ if (err)
|
|
|
+ *((int *) flags) |= PMC_FAILURE;
|
|
|
+}
|
|
|
+
|
|
|
+static void release_pmc_hardware(void)
|
|
|
+{
|
|
|
+ int flags = PMC_RELEASE;
|
|
|
+
|
|
|
+ irq_subclass_unregister(IRQ_SUBCLASS_MEASUREMENT_ALERT);
|
|
|
+ on_each_cpu(setup_pmc_cpu, &flags, 1);
|
|
|
+ perf_release_sampling();
|
|
|
+}
|
|
|
+
|
|
|
+static int reserve_pmc_hardware(void)
|
|
|
+{
|
|
|
+ int flags = PMC_INIT;
|
|
|
+ int err;
|
|
|
+
|
|
|
+ err = perf_reserve_sampling();
|
|
|
+ if (err)
|
|
|
+ return err;
|
|
|
+ on_each_cpu(setup_pmc_cpu, &flags, 1);
|
|
|
+ if (flags & PMC_FAILURE) {
|
|
|
+ release_pmc_hardware();
|
|
|
+ return -ENODEV;
|
|
|
+ }
|
|
|
+ irq_subclass_register(IRQ_SUBCLASS_MEASUREMENT_ALERT);
|
|
|
+
|
|
|
+ return 0;
|
|
|
+}
|
|
|
+
|
|
|
+static void hw_perf_event_destroy(struct perf_event *event)
|
|
|
+{
|
|
|
+ /* Free raw sample buffer */
|
|
|
+ if (RAWSAMPLE_REG(&event->hw))
|
|
|
+ kfree((void *) RAWSAMPLE_REG(&event->hw));
|
|
|
+
|
|
|
+ /* Release PMC if this is the last perf event */
|
|
|
+ if (!atomic_add_unless(&num_events, -1, 1)) {
|
|
|
+ mutex_lock(&pmc_reserve_mutex);
|
|
|
+ if (atomic_dec_return(&num_events) == 0)
|
|
|
+ release_pmc_hardware();
|
|
|
+ mutex_unlock(&pmc_reserve_mutex);
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+static void hw_init_period(struct hw_perf_event *hwc, u64 period)
|
|
|
+{
|
|
|
+ hwc->sample_period = period;
|
|
|
+ hwc->last_period = hwc->sample_period;
|
|
|
+ local64_set(&hwc->period_left, hwc->sample_period);
|
|
|
+}
|
|
|
+
|
|
|
+static void hw_reset_registers(struct hw_perf_event *hwc,
|
|
|
+ unsigned long *sdbt_origin)
|
|
|
+{
|
|
|
+ struct sf_raw_sample *sfr;
|
|
|
+
|
|
|
+ /* (Re)set to first sample-data-block-table */
|
|
|
+ TEAR_REG(hwc) = (unsigned long) sdbt_origin;
|
|
|
+
|
|
|
+ /* (Re)set raw sampling buffer register */
|
|
|
+ sfr = (struct sf_raw_sample *) RAWSAMPLE_REG(hwc);
|
|
|
+ memset(&sfr->basic, 0, sizeof(sfr->basic));
|
|
|
+ memset(&sfr->diag, 0, sfr->dsdes);
|
|
|
+}
|
|
|
+
|
|
|
+static unsigned long hw_limit_rate(const struct hws_qsi_info_block *si,
|
|
|
+ unsigned long rate)
|
|
|
+{
|
|
|
+ return clamp_t(unsigned long, rate,
|
|
|
+ si->min_sampl_rate, si->max_sampl_rate);
|
|
|
+}
|
|
|
+
|
|
|
+static int __hw_perf_event_init(struct perf_event *event)
|
|
|
+{
|
|
|
+ struct cpu_hw_sf *cpuhw;
|
|
|
+ struct hws_qsi_info_block si;
|
|
|
+ struct perf_event_attr *attr = &event->attr;
|
|
|
+ struct hw_perf_event *hwc = &event->hw;
|
|
|
+ unsigned long rate;
|
|
|
+ int cpu, err;
|
|
|
+
|
|
|
+ /* Reserve CPU-measurement sampling facility */
|
|
|
+ err = 0;
|
|
|
+ if (!atomic_inc_not_zero(&num_events)) {
|
|
|
+ mutex_lock(&pmc_reserve_mutex);
|
|
|
+ if (atomic_read(&num_events) == 0 && reserve_pmc_hardware())
|
|
|
+ err = -EBUSY;
|
|
|
+ else
|
|
|
+ atomic_inc(&num_events);
|
|
|
+ mutex_unlock(&pmc_reserve_mutex);
|
|
|
+ }
|
|
|
+ event->destroy = hw_perf_event_destroy;
|
|
|
+
|
|
|
+ if (err)
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ /* Access per-CPU sampling information (query sampling info) */
|
|
|
+ /*
|
|
|
+ * The event->cpu value can be -1 to count on every CPU, for example,
|
|
|
+ * when attaching to a task. If this is specified, use the query
|
|
|
+ * sampling info from the current CPU, otherwise use event->cpu to
|
|
|
+ * retrieve the per-CPU information.
|
|
|
+ * Later, cpuhw indicates whether to allocate sampling buffers for a
|
|
|
+ * particular CPU (cpuhw!=NULL) or each online CPU (cpuw==NULL).
|
|
|
+ */
|
|
|
+ memset(&si, 0, sizeof(si));
|
|
|
+ cpuhw = NULL;
|
|
|
+ if (event->cpu == -1)
|
|
|
+ qsi(&si);
|
|
|
+ else {
|
|
|
+ /* Event is pinned to a particular CPU, retrieve the per-CPU
|
|
|
+ * sampling structure for accessing the CPU-specific QSI.
|
|
|
+ */
|
|
|
+ cpuhw = &per_cpu(cpu_hw_sf, event->cpu);
|
|
|
+ si = cpuhw->qsi;
|
|
|
+ }
|
|
|
+
|
|
|
+ /* Check sampling facility authorization and, if not authorized,
|
|
|
+ * fall back to other PMUs. It is safe to check any CPU because
|
|
|
+ * the authorization is identical for all configured CPUs.
|
|
|
+ */
|
|
|
+ if (!si.as) {
|
|
|
+ err = -ENOENT;
|
|
|
+ goto out;
|
|
|
+ }
|
|
|
+
|
|
|
+ /* Always enable basic sampling */
|
|
|
+ SAMPL_FLAGS(hwc) = PERF_CPUM_SF_BASIC_MODE;
|
|
|
+
|
|
|
+ /* Check if diagnostic sampling is requested. Deny if the required
|
|
|
+ * sampling authorization is missing.
|
|
|
+ */
|
|
|
+ if (attr->config == PERF_EVENT_CPUM_SF_DIAG) {
|
|
|
+ if (!si.ad) {
|
|
|
+ err = -EPERM;
|
|
|
+ goto out;
|
|
|
+ }
|
|
|
+ SAMPL_FLAGS(hwc) |= PERF_CPUM_SF_DIAG_MODE;
|
|
|
+ }
|
|
|
+
|
|
|
+ /* Check and set other sampling flags */
|
|
|
+ if (attr->config1 & PERF_CPUM_SF_FULL_BLOCKS)
|
|
|
+ SAMPL_FLAGS(hwc) |= PERF_CPUM_SF_FULL_BLOCKS;
|
|
|
+
|
|
|
+ /* The sampling information (si) contains information about the
|
|
|
+ * min/max sampling intervals and the CPU speed. So calculate the
|
|
|
+ * correct sampling interval and avoid the whole period adjust
|
|
|
+ * feedback loop.
|
|
|
+ */
|
|
|
+ rate = 0;
|
|
|
+ if (attr->freq) {
|
|
|
+ rate = freq_to_sample_rate(&si, attr->sample_freq);
|
|
|
+ rate = hw_limit_rate(&si, rate);
|
|
|
+ attr->freq = 0;
|
|
|
+ attr->sample_period = rate;
|
|
|
+ } else {
|
|
|
+ /* The min/max sampling rates specifies the valid range
|
|
|
+ * of sample periods. If the specified sample period is
|
|
|
+ * out of range, limit the period to the range boundary.
|
|
|
+ */
|
|
|
+ rate = hw_limit_rate(&si, hwc->sample_period);
|
|
|
+
|
|
|
+ /* The perf core maintains a maximum sample rate that is
|
|
|
+ * configurable through the sysctl interface. Ensure the
|
|
|
+ * sampling rate does not exceed this value. This also helps
|
|
|
+ * to avoid throttling when pushing samples with
|
|
|
+ * perf_event_overflow().
|
|
|
+ */
|
|
|
+ if (sample_rate_to_freq(&si, rate) >
|
|
|
+ sysctl_perf_event_sample_rate) {
|
|
|
+ err = -EINVAL;
|
|
|
+ debug_sprintf_event(sfdbg, 1, "Sampling rate exceeds maximum perf sample rate\n");
|
|
|
+ goto out;
|
|
|
+ }
|
|
|
+ }
|
|
|
+ SAMPL_RATE(hwc) = rate;
|
|
|
+ hw_init_period(hwc, SAMPL_RATE(hwc));
|
|
|
+
|
|
|
+ /* Initialize sample data overflow accounting */
|
|
|
+ hwc->extra_reg.reg = REG_OVERFLOW;
|
|
|
+ OVERFLOW_REG(hwc) = 0;
|
|
|
+
|
|
|
+ /* Allocate the per-CPU sampling buffer using the CPU information
|
|
|
+ * from the event. If the event is not pinned to a particular
|
|
|
+ * CPU (event->cpu == -1; or cpuhw == NULL), allocate sampling
|
|
|
+ * buffers for each online CPU.
|
|
|
+ */
|
|
|
+ if (cpuhw)
|
|
|
+ /* Event is pinned to a particular CPU */
|
|
|
+ err = allocate_buffers(cpuhw, hwc);
|
|
|
+ else {
|
|
|
+ /* Event is not pinned, allocate sampling buffer on
|
|
|
+ * each online CPU
|
|
|
+ */
|
|
|
+ for_each_online_cpu(cpu) {
|
|
|
+ cpuhw = &per_cpu(cpu_hw_sf, cpu);
|
|
|
+ err = allocate_buffers(cpuhw, hwc);
|
|
|
+ if (err)
|
|
|
+ break;
|
|
|
+ }
|
|
|
+ }
|
|
|
+out:
|
|
|
+ return err;
|
|
|
+}
|
|
|
+
|
|
|
+static int cpumsf_pmu_event_init(struct perf_event *event)
|
|
|
+{
|
|
|
+ int err;
|
|
|
+
|
|
|
+ /* No support for taken branch sampling */
|
|
|
+ if (has_branch_stack(event))
|
|
|
+ return -EOPNOTSUPP;
|
|
|
+
|
|
|
+ switch (event->attr.type) {
|
|
|
+ case PERF_TYPE_RAW:
|
|
|
+ if ((event->attr.config != PERF_EVENT_CPUM_SF) &&
|
|
|
+ (event->attr.config != PERF_EVENT_CPUM_SF_DIAG))
|
|
|
+ return -ENOENT;
|
|
|
+ break;
|
|
|
+ case PERF_TYPE_HARDWARE:
|
|
|
+ /* Support sampling of CPU cycles in addition to the
|
|
|
+ * counter facility. However, the counter facility
|
|
|
+ * is more precise and, hence, restrict this PMU to
|
|
|
+ * sampling events only.
|
|
|
+ */
|
|
|
+ if (event->attr.config != PERF_COUNT_HW_CPU_CYCLES)
|
|
|
+ return -ENOENT;
|
|
|
+ if (!is_sampling_event(event))
|
|
|
+ return -ENOENT;
|
|
|
+ break;
|
|
|
+ default:
|
|
|
+ return -ENOENT;
|
|
|
+ }
|
|
|
+
|
|
|
+ /* Check online status of the CPU to which the event is pinned */
|
|
|
+ if (event->cpu >= nr_cpumask_bits ||
|
|
|
+ (event->cpu >= 0 && !cpu_online(event->cpu)))
|
|
|
+ return -ENODEV;
|
|
|
+
|
|
|
+ /* Force reset of idle/hv excludes regardless of what the
|
|
|
+ * user requested.
|
|
|
+ */
|
|
|
+ if (event->attr.exclude_hv)
|
|
|
+ event->attr.exclude_hv = 0;
|
|
|
+ if (event->attr.exclude_idle)
|
|
|
+ event->attr.exclude_idle = 0;
|
|
|
+
|
|
|
+ err = __hw_perf_event_init(event);
|
|
|
+ if (unlikely(err))
|
|
|
+ if (event->destroy)
|
|
|
+ event->destroy(event);
|
|
|
+ return err;
|
|
|
+}
|
|
|
+
|
|
|
+static void cpumsf_pmu_enable(struct pmu *pmu)
|
|
|
+{
|
|
|
+ struct cpu_hw_sf *cpuhw = &__get_cpu_var(cpu_hw_sf);
|
|
|
+ struct hw_perf_event *hwc;
|
|
|
+ int err;
|
|
|
+
|
|
|
+ if (cpuhw->flags & PMU_F_ENABLED)
|
|
|
+ return;
|
|
|
+
|
|
|
+ if (cpuhw->flags & PMU_F_ERR_MASK)
|
|
|
+ return;
|
|
|
+
|
|
|
+ /* Check whether to extent the sampling buffer.
|
|
|
+ *
|
|
|
+ * Two conditions trigger an increase of the sampling buffer for a
|
|
|
+ * perf event:
|
|
|
+ * 1. Postponed buffer allocations from the event initialization.
|
|
|
+ * 2. Sampling overflows that contribute to pending allocations.
|
|
|
+ *
|
|
|
+ * Note that the extend_sampling_buffer() function disables the sampling
|
|
|
+ * facility, but it can be fully re-enabled using sampling controls that
|
|
|
+ * have been saved in cpumsf_pmu_disable().
|
|
|
+ */
|
|
|
+ if (cpuhw->event) {
|
|
|
+ hwc = &cpuhw->event->hw;
|
|
|
+ /* Account number of overflow-designated buffer extents */
|
|
|
+ sfb_account_overflows(cpuhw, hwc);
|
|
|
+ if (sfb_has_pending_allocs(&cpuhw->sfb, hwc))
|
|
|
+ extend_sampling_buffer(&cpuhw->sfb, hwc);
|
|
|
+ }
|
|
|
+
|
|
|
+ /* (Re)enable the PMU and sampling facility */
|
|
|
+ cpuhw->flags |= PMU_F_ENABLED;
|
|
|
+ barrier();
|
|
|
+
|
|
|
+ err = lsctl(&cpuhw->lsctl);
|
|
|
+ if (err) {
|
|
|
+ cpuhw->flags &= ~PMU_F_ENABLED;
|
|
|
+ pr_err("Loading sampling controls failed: op=%i err=%i\n",
|
|
|
+ 1, err);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+
|
|
|
+ debug_sprintf_event(sfdbg, 6, "pmu_enable: es=%i cs=%i ed=%i cd=%i "
|
|
|
+ "tear=%p dear=%p\n", cpuhw->lsctl.es, cpuhw->lsctl.cs,
|
|
|
+ cpuhw->lsctl.ed, cpuhw->lsctl.cd,
|
|
|
+ (void *) cpuhw->lsctl.tear, (void *) cpuhw->lsctl.dear);
|
|
|
+}
|
|
|
+
|
|
|
+static void cpumsf_pmu_disable(struct pmu *pmu)
|
|
|
+{
|
|
|
+ struct cpu_hw_sf *cpuhw = &__get_cpu_var(cpu_hw_sf);
|
|
|
+ struct hws_lsctl_request_block inactive;
|
|
|
+ struct hws_qsi_info_block si;
|
|
|
+ int err;
|
|
|
+
|
|
|
+ if (!(cpuhw->flags & PMU_F_ENABLED))
|
|
|
+ return;
|
|
|
+
|
|
|
+ if (cpuhw->flags & PMU_F_ERR_MASK)
|
|
|
+ return;
|
|
|
+
|
|
|
+ /* Switch off sampling activation control */
|
|
|
+ inactive = cpuhw->lsctl;
|
|
|
+ inactive.cs = 0;
|
|
|
+ inactive.cd = 0;
|
|
|
+
|
|
|
+ err = lsctl(&inactive);
|
|
|
+ if (err) {
|
|
|
+ pr_err("Loading sampling controls failed: op=%i err=%i\n",
|
|
|
+ 2, err);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+
|
|
|
+ /* Save state of TEAR and DEAR register contents */
|
|
|
+ if (!qsi(&si)) {
|
|
|
+ /* TEAR/DEAR values are valid only if the sampling facility is
|
|
|
+ * enabled. Note that cpumsf_pmu_disable() might be called even
|
|
|
+ * for a disabled sampling facility because cpumsf_pmu_enable()
|
|
|
+ * controls the enable/disable state.
|
|
|
+ */
|
|
|
+ if (si.es) {
|
|
|
+ cpuhw->lsctl.tear = si.tear;
|
|
|
+ cpuhw->lsctl.dear = si.dear;
|
|
|
+ }
|
|
|
+ } else
|
|
|
+ debug_sprintf_event(sfdbg, 3, "cpumsf_pmu_disable: "
|
|
|
+ "qsi() failed with err=%i\n", err);
|
|
|
+
|
|
|
+ cpuhw->flags &= ~PMU_F_ENABLED;
|
|
|
+}
|
|
|
+
|
|
|
+/* perf_exclude_event() - Filter event
|
|
|
+ * @event: The perf event
|
|
|
+ * @regs: pt_regs structure
|
|
|
+ * @sde_regs: Sample-data-entry (sde) regs structure
|
|
|
+ *
|
|
|
+ * Filter perf events according to their exclude specification.
|
|
|
+ *
|
|
|
+ * Return non-zero if the event shall be excluded.
|
|
|
+ */
|
|
|
+static int perf_exclude_event(struct perf_event *event, struct pt_regs *regs,
|
|
|
+ struct perf_sf_sde_regs *sde_regs)
|
|
|
+{
|
|
|
+ if (event->attr.exclude_user && user_mode(regs))
|
|
|
+ return 1;
|
|
|
+ if (event->attr.exclude_kernel && !user_mode(regs))
|
|
|
+ return 1;
|
|
|
+ if (event->attr.exclude_guest && sde_regs->in_guest)
|
|
|
+ return 1;
|
|
|
+ if (event->attr.exclude_host && !sde_regs->in_guest)
|
|
|
+ return 1;
|
|
|
+ return 0;
|
|
|
+}
|
|
|
+
|
|
|
+/* perf_push_sample() - Push samples to perf
|
|
|
+ * @event: The perf event
|
|
|
+ * @sample: Hardware sample data
|
|
|
+ *
|
|
|
+ * Use the hardware sample data to create perf event sample. The sample
|
|
|
+ * is the pushed to the event subsystem and the function checks for
|
|
|
+ * possible event overflows. If an event overflow occurs, the PMU is
|
|
|
+ * stopped.
|
|
|
+ *
|
|
|
+ * Return non-zero if an event overflow occurred.
|
|
|
+ */
|
|
|
+static int perf_push_sample(struct perf_event *event, struct sf_raw_sample *sfr)
|
|
|
+{
|
|
|
+ int overflow;
|
|
|
+ struct pt_regs regs;
|
|
|
+ struct perf_sf_sde_regs *sde_regs;
|
|
|
+ struct perf_sample_data data;
|
|
|
+ struct perf_raw_record raw;
|
|
|
+
|
|
|
+ /* Setup perf sample */
|
|
|
+ perf_sample_data_init(&data, 0, event->hw.last_period);
|
|
|
+ raw.size = sfr->size;
|
|
|
+ raw.data = sfr;
|
|
|
+ data.raw = &raw;
|
|
|
+
|
|
|
+ /* Setup pt_regs to look like an CPU-measurement external interrupt
|
|
|
+ * using the Program Request Alert code. The regs.int_parm_long
|
|
|
+ * field which is unused contains additional sample-data-entry related
|
|
|
+ * indicators.
|
|
|
+ */
|
|
|
+ memset(®s, 0, sizeof(regs));
|
|
|
+ regs.int_code = 0x1407;
|
|
|
+ regs.int_parm = CPU_MF_INT_SF_PRA;
|
|
|
+ sde_regs = (struct perf_sf_sde_regs *) ®s.int_parm_long;
|
|
|
+
|
|
|
+ regs.psw.addr = sfr->basic.ia;
|
|
|
+ if (sfr->basic.T)
|
|
|
+ regs.psw.mask |= PSW_MASK_DAT;
|
|
|
+ if (sfr->basic.W)
|
|
|
+ regs.psw.mask |= PSW_MASK_WAIT;
|
|
|
+ if (sfr->basic.P)
|
|
|
+ regs.psw.mask |= PSW_MASK_PSTATE;
|
|
|
+ switch (sfr->basic.AS) {
|
|
|
+ case 0x0:
|
|
|
+ regs.psw.mask |= PSW_ASC_PRIMARY;
|
|
|
+ break;
|
|
|
+ case 0x1:
|
|
|
+ regs.psw.mask |= PSW_ASC_ACCREG;
|
|
|
+ break;
|
|
|
+ case 0x2:
|
|
|
+ regs.psw.mask |= PSW_ASC_SECONDARY;
|
|
|
+ break;
|
|
|
+ case 0x3:
|
|
|
+ regs.psw.mask |= PSW_ASC_HOME;
|
|
|
+ break;
|
|
|
+ }
|
|
|
+
|
|
|
+ /* The host-program-parameter (hpp) contains the sie control
|
|
|
+ * block that is set by sie64a() in entry64.S. Check if hpp
|
|
|
+ * refers to a valid control block and set sde_regs flags
|
|
|
+ * accordingly. This would allow to use hpp values for other
|
|
|
+ * purposes too.
|
|
|
+ * For now, simply use a non-zero value as guest indicator.
|
|
|
+ */
|
|
|
+ if (sfr->basic.hpp)
|
|
|
+ sde_regs->in_guest = 1;
|
|
|
+
|
|
|
+ overflow = 0;
|
|
|
+ if (perf_exclude_event(event, ®s, sde_regs))
|
|
|
+ goto out;
|
|
|
+ if (perf_event_overflow(event, &data, ®s)) {
|
|
|
+ overflow = 1;
|
|
|
+ event->pmu->stop(event, 0);
|
|
|
+ }
|
|
|
+ perf_event_update_userpage(event);
|
|
|
+out:
|
|
|
+ return overflow;
|
|
|
+}
|
|
|
+
|
|
|
+static void perf_event_count_update(struct perf_event *event, u64 count)
|
|
|
+{
|
|
|
+ local64_add(count, &event->count);
|
|
|
+}
|
|
|
+
|
|
|
+static int sample_format_is_valid(struct hws_combined_entry *sample,
|
|
|
+ unsigned int flags)
|
|
|
+{
|
|
|
+ if (likely(flags & PERF_CPUM_SF_BASIC_MODE))
|
|
|
+ /* Only basic-sampling data entries with data-entry-format
|
|
|
+ * version of 0x0001 can be processed.
|
|
|
+ */
|
|
|
+ if (sample->basic.def != 0x0001)
|
|
|
+ return 0;
|
|
|
+ if (flags & PERF_CPUM_SF_DIAG_MODE)
|
|
|
+ /* The data-entry-format number of diagnostic-sampling data
|
|
|
+ * entries can vary. Because diagnostic data is just passed
|
|
|
+ * through, do only a sanity check on the DEF.
|
|
|
+ */
|
|
|
+ if (sample->diag.def < 0x8001)
|
|
|
+ return 0;
|
|
|
+ return 1;
|
|
|
+}
|
|
|
+
|
|
|
+static int sample_is_consistent(struct hws_combined_entry *sample,
|
|
|
+ unsigned long flags)
|
|
|
+{
|
|
|
+ /* This check applies only to basic-sampling data entries of potentially
|
|
|
+ * combined-sampling data entries. Invalid entries cannot be processed
|
|
|
+ * by the PMU and, thus, do not deliver an associated
|
|
|
+ * diagnostic-sampling data entry.
|
|
|
+ */
|
|
|
+ if (unlikely(!(flags & PERF_CPUM_SF_BASIC_MODE)))
|
|
|
+ return 0;
|
|
|
+ /*
|
|
|
+ * Samples are skipped, if they are invalid or for which the
|
|
|
+ * instruction address is not predictable, i.e., the wait-state bit is
|
|
|
+ * set.
|
|
|
+ */
|
|
|
+ if (sample->basic.I || sample->basic.W)
|
|
|
+ return 0;
|
|
|
+ return 1;
|
|
|
+}
|
|
|
+
|
|
|
+static void reset_sample_slot(struct hws_combined_entry *sample,
|
|
|
+ unsigned long flags)
|
|
|
+{
|
|
|
+ if (likely(flags & PERF_CPUM_SF_BASIC_MODE))
|
|
|
+ sample->basic.def = 0;
|
|
|
+ if (flags & PERF_CPUM_SF_DIAG_MODE)
|
|
|
+ sample->diag.def = 0;
|
|
|
+}
|
|
|
+
|
|
|
+static void sfr_store_sample(struct sf_raw_sample *sfr,
|
|
|
+ struct hws_combined_entry *sample)
|
|
|
+{
|
|
|
+ if (likely(sfr->format & PERF_CPUM_SF_BASIC_MODE))
|
|
|
+ sfr->basic = sample->basic;
|
|
|
+ if (sfr->format & PERF_CPUM_SF_DIAG_MODE)
|
|
|
+ memcpy(&sfr->diag, &sample->diag, sfr->dsdes);
|
|
|
+}
|
|
|
+
|
|
|
+static void debug_sample_entry(struct hws_combined_entry *sample,
|
|
|
+ struct hws_trailer_entry *te,
|
|
|
+ unsigned long flags)
|
|
|
+{
|
|
|
+ debug_sprintf_event(sfdbg, 4, "hw_collect_samples: Found unknown "
|
|
|
+ "sampling data entry: te->f=%i basic.def=%04x (%p)"
|
|
|
+ " diag.def=%04x (%p)\n", te->f,
|
|
|
+ sample->basic.def, &sample->basic,
|
|
|
+ (flags & PERF_CPUM_SF_DIAG_MODE)
|
|
|
+ ? sample->diag.def : 0xFFFF,
|
|
|
+ (flags & PERF_CPUM_SF_DIAG_MODE)
|
|
|
+ ? &sample->diag : NULL);
|
|
|
+}
|
|
|
+
|
|
|
+/* hw_collect_samples() - Walk through a sample-data-block and collect samples
|
|
|
+ * @event: The perf event
|
|
|
+ * @sdbt: Sample-data-block table
|
|
|
+ * @overflow: Event overflow counter
|
|
|
+ *
|
|
|
+ * Walks through a sample-data-block and collects sampling data entries that are
|
|
|
+ * then pushed to the perf event subsystem. Depending on the sampling function,
|
|
|
+ * there can be either basic-sampling or combined-sampling data entries. A
|
|
|
+ * combined-sampling data entry consists of a basic- and a diagnostic-sampling
|
|
|
+ * data entry. The sampling function is determined by the flags in the perf
|
|
|
+ * event hardware structure. The function always works with a combined-sampling
|
|
|
+ * data entry but ignores the the diagnostic portion if it is not available.
|
|
|
+ *
|
|
|
+ * Note that the implementation focuses on basic-sampling data entries and, if
|
|
|
+ * such an entry is not valid, the entire combined-sampling data entry is
|
|
|
+ * ignored.
|
|
|
+ *
|
|
|
+ * The overflow variables counts the number of samples that has been discarded
|
|
|
+ * due to a perf event overflow.
|
|
|
+ */
|
|
|
+static void hw_collect_samples(struct perf_event *event, unsigned long *sdbt,
|
|
|
+ unsigned long long *overflow)
|
|
|
+{
|
|
|
+ unsigned long flags = SAMPL_FLAGS(&event->hw);
|
|
|
+ struct hws_combined_entry *sample;
|
|
|
+ struct hws_trailer_entry *te;
|
|
|
+ struct sf_raw_sample *sfr;
|
|
|
+ size_t sample_size;
|
|
|
+
|
|
|
+ /* Prepare and initialize raw sample data */
|
|
|
+ sfr = (struct sf_raw_sample *) RAWSAMPLE_REG(&event->hw);
|
|
|
+ sfr->format = flags & PERF_CPUM_SF_MODE_MASK;
|
|
|
+
|
|
|
+ sample_size = event_sample_size(&event->hw);
|
|
|
+ te = (struct hws_trailer_entry *) trailer_entry_ptr(*sdbt);
|
|
|
+ sample = (struct hws_combined_entry *) *sdbt;
|
|
|
+ while ((unsigned long *) sample < (unsigned long *) te) {
|
|
|
+ /* Check for an empty sample */
|
|
|
+ if (!sample->basic.def)
|
|
|
+ break;
|
|
|
+
|
|
|
+ /* Update perf event period */
|
|
|
+ perf_event_count_update(event, SAMPL_RATE(&event->hw));
|
|
|
+
|
|
|
+ /* Check sampling data entry */
|
|
|
+ if (sample_format_is_valid(sample, flags)) {
|
|
|
+ /* If an event overflow occurred, the PMU is stopped to
|
|
|
+ * throttle event delivery. Remaining sample data is
|
|
|
+ * discarded.
|
|
|
+ */
|
|
|
+ if (!*overflow) {
|
|
|
+ if (sample_is_consistent(sample, flags)) {
|
|
|
+ /* Deliver sample data to perf */
|
|
|
+ sfr_store_sample(sfr, sample);
|
|
|
+ *overflow = perf_push_sample(event, sfr);
|
|
|
+ }
|
|
|
+ } else
|
|
|
+ /* Count discarded samples */
|
|
|
+ *overflow += 1;
|
|
|
+ } else {
|
|
|
+ debug_sample_entry(sample, te, flags);
|
|
|
+ /* Sample slot is not yet written or other record.
|
|
|
+ *
|
|
|
+ * This condition can occur if the buffer was reused
|
|
|
+ * from a combined basic- and diagnostic-sampling.
|
|
|
+ * If only basic-sampling is then active, entries are
|
|
|
+ * written into the larger diagnostic entries.
|
|
|
+ * This is typically the case for sample-data-blocks
|
|
|
+ * that are not full. Stop processing if the first
|
|
|
+ * invalid format was detected.
|
|
|
+ */
|
|
|
+ if (!te->f)
|
|
|
+ break;
|
|
|
+ }
|
|
|
+
|
|
|
+ /* Reset sample slot and advance to next sample */
|
|
|
+ reset_sample_slot(sample, flags);
|
|
|
+ sample += sample_size;
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+/* hw_perf_event_update() - Process sampling buffer
|
|
|
+ * @event: The perf event
|
|
|
+ * @flush_all: Flag to also flush partially filled sample-data-blocks
|
|
|
+ *
|
|
|
+ * Processes the sampling buffer and create perf event samples.
|
|
|
+ * The sampling buffer position are retrieved and saved in the TEAR_REG
|
|
|
+ * register of the specified perf event.
|
|
|
+ *
|
|
|
+ * Only full sample-data-blocks are processed. Specify the flash_all flag
|
|
|
+ * to also walk through partially filled sample-data-blocks. It is ignored
|
|
|
+ * if PERF_CPUM_SF_FULL_BLOCKS is set. The PERF_CPUM_SF_FULL_BLOCKS flag
|
|
|
+ * enforces the processing of full sample-data-blocks only (trailer entries
|
|
|
+ * with the block-full-indicator bit set).
|
|
|
+ */
|
|
|
+static void hw_perf_event_update(struct perf_event *event, int flush_all)
|
|
|
+{
|
|
|
+ struct hw_perf_event *hwc = &event->hw;
|
|
|
+ struct hws_trailer_entry *te;
|
|
|
+ unsigned long *sdbt;
|
|
|
+ unsigned long long event_overflow, sampl_overflow, num_sdb, te_flags;
|
|
|
+ int done;
|
|
|
+
|
|
|
+ if (flush_all && SDB_FULL_BLOCKS(hwc))
|
|
|
+ flush_all = 0;
|
|
|
+
|
|
|
+ sdbt = (unsigned long *) TEAR_REG(hwc);
|
|
|
+ done = event_overflow = sampl_overflow = num_sdb = 0;
|
|
|
+ while (!done) {
|
|
|
+ /* Get the trailer entry of the sample-data-block */
|
|
|
+ te = (struct hws_trailer_entry *) trailer_entry_ptr(*sdbt);
|
|
|
+
|
|
|
+ /* Leave loop if no more work to do (block full indicator) */
|
|
|
+ if (!te->f) {
|
|
|
+ done = 1;
|
|
|
+ if (!flush_all)
|
|
|
+ break;
|
|
|
+ }
|
|
|
+
|
|
|
+ /* Check the sample overflow count */
|
|
|
+ if (te->overflow)
|
|
|
+ /* Account sample overflows and, if a particular limit
|
|
|
+ * is reached, extend the sampling buffer.
|
|
|
+ * For details, see sfb_account_overflows().
|
|
|
+ */
|
|
|
+ sampl_overflow += te->overflow;
|
|
|
+
|
|
|
+ /* Timestamps are valid for full sample-data-blocks only */
|
|
|
+ debug_sprintf_event(sfdbg, 6, "hw_perf_event_update: sdbt=%p "
|
|
|
+ "overflow=%llu timestamp=0x%llx\n",
|
|
|
+ sdbt, te->overflow,
|
|
|
+ (te->f) ? trailer_timestamp(te) : 0ULL);
|
|
|
+
|
|
|
+ /* Collect all samples from a single sample-data-block and
|
|
|
+ * flag if an (perf) event overflow happened. If so, the PMU
|
|
|
+ * is stopped and remaining samples will be discarded.
|
|
|
+ */
|
|
|
+ hw_collect_samples(event, sdbt, &event_overflow);
|
|
|
+ num_sdb++;
|
|
|
+
|
|
|
+ /* Reset trailer (using compare-double-and-swap) */
|
|
|
+ do {
|
|
|
+ te_flags = te->flags & ~SDB_TE_BUFFER_FULL_MASK;
|
|
|
+ te_flags |= SDB_TE_ALERT_REQ_MASK;
|
|
|
+ } while (!cmpxchg_double(&te->flags, &te->overflow,
|
|
|
+ te->flags, te->overflow,
|
|
|
+ te_flags, 0ULL));
|
|
|
+
|
|
|
+ /* Advance to next sample-data-block */
|
|
|
+ sdbt++;
|
|
|
+ if (is_link_entry(sdbt))
|
|
|
+ sdbt = get_next_sdbt(sdbt);
|
|
|
+
|
|
|
+ /* Update event hardware registers */
|
|
|
+ TEAR_REG(hwc) = (unsigned long) sdbt;
|
|
|
+
|
|
|
+ /* Stop processing sample-data if all samples of the current
|
|
|
+ * sample-data-block were flushed even if it was not full.
|
|
|
+ */
|
|
|
+ if (flush_all && done)
|
|
|
+ break;
|
|
|
+
|
|
|
+ /* If an event overflow happened, discard samples by
|
|
|
+ * processing any remaining sample-data-blocks.
|
|
|
+ */
|
|
|
+ if (event_overflow)
|
|
|
+ flush_all = 1;
|
|
|
+ }
|
|
|
+
|
|
|
+ /* Account sample overflows in the event hardware structure */
|
|
|
+ if (sampl_overflow)
|
|
|
+ OVERFLOW_REG(hwc) = DIV_ROUND_UP(OVERFLOW_REG(hwc) +
|
|
|
+ sampl_overflow, 1 + num_sdb);
|
|
|
+ if (sampl_overflow || event_overflow)
|
|
|
+ debug_sprintf_event(sfdbg, 4, "hw_perf_event_update: "
|
|
|
+ "overflow stats: sample=%llu event=%llu\n",
|
|
|
+ sampl_overflow, event_overflow);
|
|
|
+}
|
|
|
+
|
|
|
+static void cpumsf_pmu_read(struct perf_event *event)
|
|
|
+{
|
|
|
+ /* Nothing to do ... updates are interrupt-driven */
|
|
|
+}
|
|
|
+
|
|
|
+/* Activate sampling control.
|
|
|
+ * Next call of pmu_enable() starts sampling.
|
|
|
+ */
|
|
|
+static void cpumsf_pmu_start(struct perf_event *event, int flags)
|
|
|
+{
|
|
|
+ struct cpu_hw_sf *cpuhw = &__get_cpu_var(cpu_hw_sf);
|
|
|
+
|
|
|
+ if (WARN_ON_ONCE(!(event->hw.state & PERF_HES_STOPPED)))
|
|
|
+ return;
|
|
|
+
|
|
|
+ if (flags & PERF_EF_RELOAD)
|
|
|
+ WARN_ON_ONCE(!(event->hw.state & PERF_HES_UPTODATE));
|
|
|
+
|
|
|
+ perf_pmu_disable(event->pmu);
|
|
|
+ event->hw.state = 0;
|
|
|
+ cpuhw->lsctl.cs = 1;
|
|
|
+ if (SAMPL_DIAG_MODE(&event->hw))
|
|
|
+ cpuhw->lsctl.cd = 1;
|
|
|
+ perf_pmu_enable(event->pmu);
|
|
|
+}
|
|
|
+
|
|
|
+/* Deactivate sampling control.
|
|
|
+ * Next call of pmu_enable() stops sampling.
|
|
|
+ */
|
|
|
+static void cpumsf_pmu_stop(struct perf_event *event, int flags)
|
|
|
+{
|
|
|
+ struct cpu_hw_sf *cpuhw = &__get_cpu_var(cpu_hw_sf);
|
|
|
+
|
|
|
+ if (event->hw.state & PERF_HES_STOPPED)
|
|
|
+ return;
|
|
|
+
|
|
|
+ perf_pmu_disable(event->pmu);
|
|
|
+ cpuhw->lsctl.cs = 0;
|
|
|
+ cpuhw->lsctl.cd = 0;
|
|
|
+ event->hw.state |= PERF_HES_STOPPED;
|
|
|
+
|
|
|
+ if ((flags & PERF_EF_UPDATE) && !(event->hw.state & PERF_HES_UPTODATE)) {
|
|
|
+ hw_perf_event_update(event, 1);
|
|
|
+ event->hw.state |= PERF_HES_UPTODATE;
|
|
|
+ }
|
|
|
+ perf_pmu_enable(event->pmu);
|
|
|
+}
|
|
|
+
|
|
|
+static int cpumsf_pmu_add(struct perf_event *event, int flags)
|
|
|
+{
|
|
|
+ struct cpu_hw_sf *cpuhw = &__get_cpu_var(cpu_hw_sf);
|
|
|
+ int err;
|
|
|
+
|
|
|
+ if (cpuhw->flags & PMU_F_IN_USE)
|
|
|
+ return -EAGAIN;
|
|
|
+
|
|
|
+ if (!cpuhw->sfb.sdbt)
|
|
|
+ return -EINVAL;
|
|
|
+
|
|
|
+ err = 0;
|
|
|
+ perf_pmu_disable(event->pmu);
|
|
|
+
|
|
|
+ event->hw.state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
|
|
|
+
|
|
|
+ /* Set up sampling controls. Always program the sampling register
|
|
|
+ * using the SDB-table start. Reset TEAR_REG event hardware register
|
|
|
+ * that is used by hw_perf_event_update() to store the sampling buffer
|
|
|
+ * position after samples have been flushed.
|
|
|
+ */
|
|
|
+ cpuhw->lsctl.s = 0;
|
|
|
+ cpuhw->lsctl.h = 1;
|
|
|
+ cpuhw->lsctl.tear = (unsigned long) cpuhw->sfb.sdbt;
|
|
|
+ cpuhw->lsctl.dear = *(unsigned long *) cpuhw->sfb.sdbt;
|
|
|
+ cpuhw->lsctl.interval = SAMPL_RATE(&event->hw);
|
|
|
+ hw_reset_registers(&event->hw, cpuhw->sfb.sdbt);
|
|
|
+
|
|
|
+ /* Ensure sampling functions are in the disabled state. If disabled,
|
|
|
+ * switch on sampling enable control. */
|
|
|
+ if (WARN_ON_ONCE(cpuhw->lsctl.es == 1 || cpuhw->lsctl.ed == 1)) {
|
|
|
+ err = -EAGAIN;
|
|
|
+ goto out;
|
|
|
+ }
|
|
|
+ cpuhw->lsctl.es = 1;
|
|
|
+ if (SAMPL_DIAG_MODE(&event->hw))
|
|
|
+ cpuhw->lsctl.ed = 1;
|
|
|
+
|
|
|
+ /* Set in_use flag and store event */
|
|
|
+ event->hw.idx = 0; /* only one sampling event per CPU supported */
|
|
|
+ cpuhw->event = event;
|
|
|
+ cpuhw->flags |= PMU_F_IN_USE;
|
|
|
+
|
|
|
+ if (flags & PERF_EF_START)
|
|
|
+ cpumsf_pmu_start(event, PERF_EF_RELOAD);
|
|
|
+out:
|
|
|
+ perf_event_update_userpage(event);
|
|
|
+ perf_pmu_enable(event->pmu);
|
|
|
+ return err;
|
|
|
+}
|
|
|
+
|
|
|
+static void cpumsf_pmu_del(struct perf_event *event, int flags)
|
|
|
+{
|
|
|
+ struct cpu_hw_sf *cpuhw = &__get_cpu_var(cpu_hw_sf);
|
|
|
+
|
|
|
+ perf_pmu_disable(event->pmu);
|
|
|
+ cpumsf_pmu_stop(event, PERF_EF_UPDATE);
|
|
|
+
|
|
|
+ cpuhw->lsctl.es = 0;
|
|
|
+ cpuhw->lsctl.ed = 0;
|
|
|
+ cpuhw->flags &= ~PMU_F_IN_USE;
|
|
|
+ cpuhw->event = NULL;
|
|
|
+
|
|
|
+ perf_event_update_userpage(event);
|
|
|
+ perf_pmu_enable(event->pmu);
|
|
|
+}
|
|
|
+
|
|
|
+static int cpumsf_pmu_event_idx(struct perf_event *event)
|
|
|
+{
|
|
|
+ return event->hw.idx;
|
|
|
+}
|
|
|
+
|
|
|
+CPUMF_EVENT_ATTR(SF, SF_CYCLES_BASIC, PERF_EVENT_CPUM_SF);
|
|
|
+CPUMF_EVENT_ATTR(SF, SF_CYCLES_BASIC_DIAG, PERF_EVENT_CPUM_SF_DIAG);
|
|
|
+
|
|
|
+static struct attribute *cpumsf_pmu_events_attr[] = {
|
|
|
+ CPUMF_EVENT_PTR(SF, SF_CYCLES_BASIC),
|
|
|
+ CPUMF_EVENT_PTR(SF, SF_CYCLES_BASIC_DIAG),
|
|
|
+ NULL,
|
|
|
+};
|
|
|
+
|
|
|
+PMU_FORMAT_ATTR(event, "config:0-63");
|
|
|
+
|
|
|
+static struct attribute *cpumsf_pmu_format_attr[] = {
|
|
|
+ &format_attr_event.attr,
|
|
|
+ NULL,
|
|
|
+};
|
|
|
+
|
|
|
+static struct attribute_group cpumsf_pmu_events_group = {
|
|
|
+ .name = "events",
|
|
|
+ .attrs = cpumsf_pmu_events_attr,
|
|
|
+};
|
|
|
+static struct attribute_group cpumsf_pmu_format_group = {
|
|
|
+ .name = "format",
|
|
|
+ .attrs = cpumsf_pmu_format_attr,
|
|
|
+};
|
|
|
+static const struct attribute_group *cpumsf_pmu_attr_groups[] = {
|
|
|
+ &cpumsf_pmu_events_group,
|
|
|
+ &cpumsf_pmu_format_group,
|
|
|
+ NULL,
|
|
|
+};
|
|
|
+
|
|
|
+static struct pmu cpumf_sampling = {
|
|
|
+ .pmu_enable = cpumsf_pmu_enable,
|
|
|
+ .pmu_disable = cpumsf_pmu_disable,
|
|
|
+
|
|
|
+ .event_init = cpumsf_pmu_event_init,
|
|
|
+ .add = cpumsf_pmu_add,
|
|
|
+ .del = cpumsf_pmu_del,
|
|
|
+
|
|
|
+ .start = cpumsf_pmu_start,
|
|
|
+ .stop = cpumsf_pmu_stop,
|
|
|
+ .read = cpumsf_pmu_read,
|
|
|
+
|
|
|
+ .event_idx = cpumsf_pmu_event_idx,
|
|
|
+ .attr_groups = cpumsf_pmu_attr_groups,
|
|
|
+};
|
|
|
+
|
|
|
+static void cpumf_measurement_alert(struct ext_code ext_code,
|
|
|
+ unsigned int alert, unsigned long unused)
|
|
|
+{
|
|
|
+ struct cpu_hw_sf *cpuhw;
|
|
|
+
|
|
|
+ if (!(alert & CPU_MF_INT_SF_MASK))
|
|
|
+ return;
|
|
|
+ inc_irq_stat(IRQEXT_CMS);
|
|
|
+ cpuhw = &__get_cpu_var(cpu_hw_sf);
|
|
|
+
|
|
|
+ /* Measurement alerts are shared and might happen when the PMU
|
|
|
+ * is not reserved. Ignore these alerts in this case. */
|
|
|
+ if (!(cpuhw->flags & PMU_F_RESERVED))
|
|
|
+ return;
|
|
|
+
|
|
|
+ /* The processing below must take care of multiple alert events that
|
|
|
+ * might be indicated concurrently. */
|
|
|
+
|
|
|
+ /* Program alert request */
|
|
|
+ if (alert & CPU_MF_INT_SF_PRA) {
|
|
|
+ if (cpuhw->flags & PMU_F_IN_USE)
|
|
|
+ hw_perf_event_update(cpuhw->event, 0);
|
|
|
+ else
|
|
|
+ WARN_ON_ONCE(!(cpuhw->flags & PMU_F_IN_USE));
|
|
|
+ }
|
|
|
+
|
|
|
+ /* Report measurement alerts only for non-PRA codes */
|
|
|
+ if (alert != CPU_MF_INT_SF_PRA)
|
|
|
+ debug_sprintf_event(sfdbg, 6, "measurement alert: 0x%x\n", alert);
|
|
|
+
|
|
|
+ /* Sampling authorization change request */
|
|
|
+ if (alert & CPU_MF_INT_SF_SACA)
|
|
|
+ qsi(&cpuhw->qsi);
|
|
|
+
|
|
|
+ /* Loss of sample data due to high-priority machine activities */
|
|
|
+ if (alert & CPU_MF_INT_SF_LSDA) {
|
|
|
+ pr_err("Sample data was lost\n");
|
|
|
+ cpuhw->flags |= PMU_F_ERR_LSDA;
|
|
|
+ sf_disable();
|
|
|
+ }
|
|
|
+
|
|
|
+ /* Invalid sampling buffer entry */
|
|
|
+ if (alert & (CPU_MF_INT_SF_IAE|CPU_MF_INT_SF_ISE)) {
|
|
|
+ pr_err("A sampling buffer entry is incorrect (alert=0x%x)\n",
|
|
|
+ alert);
|
|
|
+ cpuhw->flags |= PMU_F_ERR_IBE;
|
|
|
+ sf_disable();
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+static int cpumf_pmu_notifier(struct notifier_block *self,
|
|
|
+ unsigned long action, void *hcpu)
|
|
|
+{
|
|
|
+ unsigned int cpu = (long) hcpu;
|
|
|
+ int flags;
|
|
|
+
|
|
|
+ /* Ignore the notification if no events are scheduled on the PMU.
|
|
|
+ * This might be racy...
|
|
|
+ */
|
|
|
+ if (!atomic_read(&num_events))
|
|
|
+ return NOTIFY_OK;
|
|
|
+
|
|
|
+ switch (action & ~CPU_TASKS_FROZEN) {
|
|
|
+ case CPU_ONLINE:
|
|
|
+ case CPU_ONLINE_FROZEN:
|
|
|
+ flags = PMC_INIT;
|
|
|
+ smp_call_function_single(cpu, setup_pmc_cpu, &flags, 1);
|
|
|
+ break;
|
|
|
+ case CPU_DOWN_PREPARE:
|
|
|
+ flags = PMC_RELEASE;
|
|
|
+ smp_call_function_single(cpu, setup_pmc_cpu, &flags, 1);
|
|
|
+ break;
|
|
|
+ default:
|
|
|
+ break;
|
|
|
+ }
|
|
|
+
|
|
|
+ return NOTIFY_OK;
|
|
|
+}
|
|
|
+
|
|
|
+static int param_get_sfb_size(char *buffer, const struct kernel_param *kp)
|
|
|
+{
|
|
|
+ if (!cpum_sf_avail())
|
|
|
+ return -ENODEV;
|
|
|
+ return sprintf(buffer, "%lu,%lu", CPUM_SF_MIN_SDB, CPUM_SF_MAX_SDB);
|
|
|
+}
|
|
|
+
|
|
|
+static int param_set_sfb_size(const char *val, const struct kernel_param *kp)
|
|
|
+{
|
|
|
+ int rc;
|
|
|
+ unsigned long min, max;
|
|
|
+
|
|
|
+ if (!cpum_sf_avail())
|
|
|
+ return -ENODEV;
|
|
|
+ if (!val || !strlen(val))
|
|
|
+ return -EINVAL;
|
|
|
+
|
|
|
+ /* Valid parameter values: "min,max" or "max" */
|
|
|
+ min = CPUM_SF_MIN_SDB;
|
|
|
+ max = CPUM_SF_MAX_SDB;
|
|
|
+ if (strchr(val, ','))
|
|
|
+ rc = (sscanf(val, "%lu,%lu", &min, &max) == 2) ? 0 : -EINVAL;
|
|
|
+ else
|
|
|
+ rc = kstrtoul(val, 10, &max);
|
|
|
+
|
|
|
+ if (min < 2 || min >= max || max > get_num_physpages())
|
|
|
+ rc = -EINVAL;
|
|
|
+ if (rc)
|
|
|
+ return rc;
|
|
|
+
|
|
|
+ sfb_set_limits(min, max);
|
|
|
+ pr_info("The sampling buffer limits have changed to: "
|
|
|
+ "min=%lu max=%lu (diag=x%lu)\n",
|
|
|
+ CPUM_SF_MIN_SDB, CPUM_SF_MAX_SDB, CPUM_SF_SDB_DIAG_FACTOR);
|
|
|
+ return 0;
|
|
|
+}
|
|
|
+
|
|
|
+#define param_check_sfb_size(name, p) __param_check(name, p, void)
|
|
|
+static struct kernel_param_ops param_ops_sfb_size = {
|
|
|
+ .set = param_set_sfb_size,
|
|
|
+ .get = param_get_sfb_size,
|
|
|
+};
|
|
|
+
|
|
|
+#define RS_INIT_FAILURE_QSI 0x0001
|
|
|
+#define RS_INIT_FAILURE_BSDES 0x0002
|
|
|
+#define RS_INIT_FAILURE_ALRT 0x0003
|
|
|
+#define RS_INIT_FAILURE_PERF 0x0004
|
|
|
+static void __init pr_cpumsf_err(unsigned int reason)
|
|
|
+{
|
|
|
+ pr_err("Sampling facility support for perf is not available: "
|
|
|
+ "reason=%04x\n", reason);
|
|
|
+}
|
|
|
+
|
|
|
+static int __init init_cpum_sampling_pmu(void)
|
|
|
+{
|
|
|
+ struct hws_qsi_info_block si;
|
|
|
+ int err;
|
|
|
+
|
|
|
+ if (!cpum_sf_avail())
|
|
|
+ return -ENODEV;
|
|
|
+
|
|
|
+ memset(&si, 0, sizeof(si));
|
|
|
+ if (qsi(&si)) {
|
|
|
+ pr_cpumsf_err(RS_INIT_FAILURE_QSI);
|
|
|
+ return -ENODEV;
|
|
|
+ }
|
|
|
+
|
|
|
+ if (si.bsdes != sizeof(struct hws_basic_entry)) {
|
|
|
+ pr_cpumsf_err(RS_INIT_FAILURE_BSDES);
|
|
|
+ return -EINVAL;
|
|
|
+ }
|
|
|
+
|
|
|
+ if (si.ad)
|
|
|
+ sfb_set_limits(CPUM_SF_MIN_SDB, CPUM_SF_MAX_SDB);
|
|
|
+
|
|
|
+ sfdbg = debug_register(KMSG_COMPONENT, 2, 1, 80);
|
|
|
+ if (!sfdbg)
|
|
|
+ pr_err("Registering for s390dbf failed\n");
|
|
|
+ debug_register_view(sfdbg, &debug_sprintf_view);
|
|
|
+
|
|
|
+ err = register_external_interrupt(0x1407, cpumf_measurement_alert);
|
|
|
+ if (err) {
|
|
|
+ pr_cpumsf_err(RS_INIT_FAILURE_ALRT);
|
|
|
+ goto out;
|
|
|
+ }
|
|
|
+
|
|
|
+ err = perf_pmu_register(&cpumf_sampling, "cpum_sf", PERF_TYPE_RAW);
|
|
|
+ if (err) {
|
|
|
+ pr_cpumsf_err(RS_INIT_FAILURE_PERF);
|
|
|
+ unregister_external_interrupt(0x1407, cpumf_measurement_alert);
|
|
|
+ goto out;
|
|
|
+ }
|
|
|
+ perf_cpu_notifier(cpumf_pmu_notifier);
|
|
|
+out:
|
|
|
+ return err;
|
|
|
+}
|
|
|
+arch_initcall(init_cpum_sampling_pmu);
|
|
|
+core_param(cpum_sfb_size, CPUM_SF_MAX_SDB, sfb_size, 0640);
|
Linus Torvalds