diff options
Diffstat (limited to 'drivers/misc/sgi-gru/grukservices.c')
-rw-r--r-- | drivers/misc/sgi-gru/grukservices.c | 1171 |
1 files changed, 1171 insertions, 0 deletions
diff --git a/drivers/misc/sgi-gru/grukservices.c b/drivers/misc/sgi-gru/grukservices.c new file mode 100644 index 000000000..030769018 --- /dev/null +++ b/drivers/misc/sgi-gru/grukservices.c @@ -0,0 +1,1171 @@ +/* + * SN Platform GRU Driver + * + * KERNEL SERVICES THAT USE THE GRU + * + * Copyright (c) 2008 Silicon Graphics, Inc. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/slab.h> +#include <linux/mm.h> +#include <linux/spinlock.h> +#include <linux/device.h> +#include <linux/miscdevice.h> +#include <linux/proc_fs.h> +#include <linux/interrupt.h> +#include <linux/uaccess.h> +#include <linux/delay.h> +#include <linux/export.h> +#include <asm/io_apic.h> +#include "gru.h" +#include "grulib.h" +#include "grutables.h" +#include "grukservices.h" +#include "gru_instructions.h" +#include <asm/uv/uv_hub.h> + +/* + * Kernel GRU Usage + * + * The following is an interim algorithm for management of kernel GRU + * resources. This will likely be replaced when we better understand the + * kernel/user requirements. + * + * Blade percpu resources reserved for kernel use. These resources are + * reserved whenever the the kernel context for the blade is loaded. Note + * that the kernel context is not guaranteed to be always available. It is + * loaded on demand & can be stolen by a user if the user demand exceeds the + * kernel demand. The kernel can always reload the kernel context but + * a SLEEP may be required!!!. + * + * Async Overview: + * + * Each blade has one "kernel context" that owns GRU kernel resources + * located on the blade. Kernel drivers use GRU resources in this context + * for sending messages, zeroing memory, etc. + * + * The kernel context is dynamically loaded on demand. If it is not in + * use by the kernel, the kernel context can be unloaded & given to a user. + * The kernel context will be reloaded when needed. This may require that + * a context be stolen from a user. + * NOTE: frequent unloading/reloading of the kernel context is + * expensive. We are depending on batch schedulers, cpusets, sane + * drivers or some other mechanism to prevent the need for frequent + * stealing/reloading. + * + * The kernel context consists of two parts: + * - 1 CB & a few DSRs that are reserved for each cpu on the blade. + * Each cpu has it's own private resources & does not share them + * with other cpus. These resources are used serially, ie, + * locked, used & unlocked on each call to a function in + * grukservices. + * (Now that we have dynamic loading of kernel contexts, I + * may rethink this & allow sharing between cpus....) + * + * - Additional resources can be reserved long term & used directly + * by UV drivers located in the kernel. Drivers using these GRU + * resources can use asynchronous GRU instructions that send + * interrupts on completion. + * - these resources must be explicitly locked/unlocked + * - locked resources prevent (obviously) the kernel + * context from being unloaded. + * - drivers using these resource directly issue their own + * GRU instruction and must wait/check completion. + * + * When these resources are reserved, the caller can optionally + * associate a wait_queue with the resources and use asynchronous + * GRU instructions. When an async GRU instruction completes, the + * driver will do a wakeup on the event. + * + */ + + +#define ASYNC_HAN_TO_BID(h) ((h) - 1) +#define ASYNC_BID_TO_HAN(b) ((b) + 1) +#define ASYNC_HAN_TO_BS(h) gru_base[ASYNC_HAN_TO_BID(h)] + +#define GRU_NUM_KERNEL_CBR 1 +#define GRU_NUM_KERNEL_DSR_BYTES 256 +#define GRU_NUM_KERNEL_DSR_CL (GRU_NUM_KERNEL_DSR_BYTES / \ + GRU_CACHE_LINE_BYTES) + +/* GRU instruction attributes for all instructions */ +#define IMA IMA_CB_DELAY + +/* GRU cacheline size is always 64 bytes - even on arches with 128 byte lines */ +#define __gru_cacheline_aligned__ \ + __attribute__((__aligned__(GRU_CACHE_LINE_BYTES))) + +#define MAGIC 0x1234567887654321UL + +/* Default retry count for GRU errors on kernel instructions */ +#define EXCEPTION_RETRY_LIMIT 3 + +/* Status of message queue sections */ +#define MQS_EMPTY 0 +#define MQS_FULL 1 +#define MQS_NOOP 2 + +/*----------------- RESOURCE MANAGEMENT -------------------------------------*/ +/* optimized for x86_64 */ +struct message_queue { + union gru_mesqhead head __gru_cacheline_aligned__; /* CL 0 */ + int qlines; /* DW 1 */ + long hstatus[2]; + void *next __gru_cacheline_aligned__;/* CL 1 */ + void *limit; + void *start; + void *start2; + char data ____cacheline_aligned; /* CL 2 */ +}; + +/* First word in every message - used by mesq interface */ +struct message_header { + char present; + char present2; + char lines; + char fill; +}; + +#define HSTATUS(mq, h) ((mq) + offsetof(struct message_queue, hstatus[h])) + +/* + * Reload the blade's kernel context into a GRU chiplet. Called holding + * the bs_kgts_sema for READ. Will steal user contexts if necessary. + */ +static void gru_load_kernel_context(struct gru_blade_state *bs, int blade_id) +{ + struct gru_state *gru; + struct gru_thread_state *kgts; + void *vaddr; + int ctxnum, ncpus; + + up_read(&bs->bs_kgts_sema); + down_write(&bs->bs_kgts_sema); + + if (!bs->bs_kgts) { + do { + bs->bs_kgts = gru_alloc_gts(NULL, 0, 0, 0, 0, 0); + if (!IS_ERR(bs->bs_kgts)) + break; + msleep(1); + } while (true); + bs->bs_kgts->ts_user_blade_id = blade_id; + } + kgts = bs->bs_kgts; + + if (!kgts->ts_gru) { + STAT(load_kernel_context); + ncpus = uv_blade_nr_possible_cpus(blade_id); + kgts->ts_cbr_au_count = GRU_CB_COUNT_TO_AU( + GRU_NUM_KERNEL_CBR * ncpus + bs->bs_async_cbrs); + kgts->ts_dsr_au_count = GRU_DS_BYTES_TO_AU( + GRU_NUM_KERNEL_DSR_BYTES * ncpus + + bs->bs_async_dsr_bytes); + while (!gru_assign_gru_context(kgts)) { + msleep(1); + gru_steal_context(kgts); + } + gru_load_context(kgts); + gru = bs->bs_kgts->ts_gru; + vaddr = gru->gs_gru_base_vaddr; + ctxnum = kgts->ts_ctxnum; + bs->kernel_cb = get_gseg_base_address_cb(vaddr, ctxnum, 0); + bs->kernel_dsr = get_gseg_base_address_ds(vaddr, ctxnum, 0); + } + downgrade_write(&bs->bs_kgts_sema); +} + +/* + * Free all kernel contexts that are not currently in use. + * Returns 0 if all freed, else number of inuse context. + */ +static int gru_free_kernel_contexts(void) +{ + struct gru_blade_state *bs; + struct gru_thread_state *kgts; + int bid, ret = 0; + + for (bid = 0; bid < GRU_MAX_BLADES; bid++) { + bs = gru_base[bid]; + if (!bs) + continue; + + /* Ignore busy contexts. Don't want to block here. */ + if (down_write_trylock(&bs->bs_kgts_sema)) { + kgts = bs->bs_kgts; + if (kgts && kgts->ts_gru) + gru_unload_context(kgts, 0); + bs->bs_kgts = NULL; + up_write(&bs->bs_kgts_sema); + kfree(kgts); + } else { + ret++; + } + } + return ret; +} + +/* + * Lock & load the kernel context for the specified blade. + */ +static struct gru_blade_state *gru_lock_kernel_context(int blade_id) +{ + struct gru_blade_state *bs; + int bid; + + STAT(lock_kernel_context); +again: + bid = blade_id < 0 ? uv_numa_blade_id() : blade_id; + bs = gru_base[bid]; + + /* Handle the case where migration occurred while waiting for the sema */ + down_read(&bs->bs_kgts_sema); + if (blade_id < 0 && bid != uv_numa_blade_id()) { + up_read(&bs->bs_kgts_sema); + goto again; + } + if (!bs->bs_kgts || !bs->bs_kgts->ts_gru) + gru_load_kernel_context(bs, bid); + return bs; + +} + +/* + * Unlock the kernel context for the specified blade. Context is not + * unloaded but may be stolen before next use. + */ +static void gru_unlock_kernel_context(int blade_id) +{ + struct gru_blade_state *bs; + + bs = gru_base[blade_id]; + up_read(&bs->bs_kgts_sema); + STAT(unlock_kernel_context); +} + +/* + * Reserve & get pointers to the DSR/CBRs reserved for the current cpu. + * - returns with preemption disabled + */ +static int gru_get_cpu_resources(int dsr_bytes, void **cb, void **dsr) +{ + struct gru_blade_state *bs; + int lcpu; + + BUG_ON(dsr_bytes > GRU_NUM_KERNEL_DSR_BYTES); + preempt_disable(); + bs = gru_lock_kernel_context(-1); + lcpu = uv_blade_processor_id(); + *cb = bs->kernel_cb + lcpu * GRU_HANDLE_STRIDE; + *dsr = bs->kernel_dsr + lcpu * GRU_NUM_KERNEL_DSR_BYTES; + return 0; +} + +/* + * Free the current cpus reserved DSR/CBR resources. + */ +static void gru_free_cpu_resources(void *cb, void *dsr) +{ + gru_unlock_kernel_context(uv_numa_blade_id()); + preempt_enable(); +} + +/* + * Reserve GRU resources to be used asynchronously. + * Note: currently supports only 1 reservation per blade. + * + * input: + * blade_id - blade on which resources should be reserved + * cbrs - number of CBRs + * dsr_bytes - number of DSR bytes needed + * output: + * handle to identify resource + * (0 = async resources already reserved) + */ +unsigned long gru_reserve_async_resources(int blade_id, int cbrs, int dsr_bytes, + struct completion *cmp) +{ + struct gru_blade_state *bs; + struct gru_thread_state *kgts; + int ret = 0; + + bs = gru_base[blade_id]; + + down_write(&bs->bs_kgts_sema); + + /* Verify no resources already reserved */ + if (bs->bs_async_dsr_bytes + bs->bs_async_cbrs) + goto done; + bs->bs_async_dsr_bytes = dsr_bytes; + bs->bs_async_cbrs = cbrs; + bs->bs_async_wq = cmp; + kgts = bs->bs_kgts; + + /* Resources changed. Unload context if already loaded */ + if (kgts && kgts->ts_gru) + gru_unload_context(kgts, 0); + ret = ASYNC_BID_TO_HAN(blade_id); + +done: + up_write(&bs->bs_kgts_sema); + return ret; +} + +/* + * Release async resources previously reserved. + * + * input: + * han - handle to identify resources + */ +void gru_release_async_resources(unsigned long han) +{ + struct gru_blade_state *bs = ASYNC_HAN_TO_BS(han); + + down_write(&bs->bs_kgts_sema); + bs->bs_async_dsr_bytes = 0; + bs->bs_async_cbrs = 0; + bs->bs_async_wq = NULL; + up_write(&bs->bs_kgts_sema); +} + +/* + * Wait for async GRU instructions to complete. + * + * input: + * han - handle to identify resources + */ +void gru_wait_async_cbr(unsigned long han) +{ + struct gru_blade_state *bs = ASYNC_HAN_TO_BS(han); + + wait_for_completion(bs->bs_async_wq); + mb(); +} + +/* + * Lock previous reserved async GRU resources + * + * input: + * han - handle to identify resources + * output: + * cb - pointer to first CBR + * dsr - pointer to first DSR + */ +void gru_lock_async_resource(unsigned long han, void **cb, void **dsr) +{ + struct gru_blade_state *bs = ASYNC_HAN_TO_BS(han); + int blade_id = ASYNC_HAN_TO_BID(han); + int ncpus; + + gru_lock_kernel_context(blade_id); + ncpus = uv_blade_nr_possible_cpus(blade_id); + if (cb) + *cb = bs->kernel_cb + ncpus * GRU_HANDLE_STRIDE; + if (dsr) + *dsr = bs->kernel_dsr + ncpus * GRU_NUM_KERNEL_DSR_BYTES; +} + +/* + * Unlock previous reserved async GRU resources + * + * input: + * han - handle to identify resources + */ +void gru_unlock_async_resource(unsigned long han) +{ + int blade_id = ASYNC_HAN_TO_BID(han); + + gru_unlock_kernel_context(blade_id); +} + +/*----------------------------------------------------------------------*/ +int gru_get_cb_exception_detail(void *cb, + struct control_block_extended_exc_detail *excdet) +{ + struct gru_control_block_extended *cbe; + struct gru_thread_state *kgts = NULL; + unsigned long off; + int cbrnum, bid; + + /* + * Locate kgts for cb. This algorithm is SLOW but + * this function is rarely called (ie., almost never). + * Performance does not matter. + */ + for_each_possible_blade(bid) { + if (!gru_base[bid]) + break; + kgts = gru_base[bid]->bs_kgts; + if (!kgts || !kgts->ts_gru) + continue; + off = cb - kgts->ts_gru->gs_gru_base_vaddr; + if (off < GRU_SIZE) + break; + kgts = NULL; + } + BUG_ON(!kgts); + cbrnum = thread_cbr_number(kgts, get_cb_number(cb)); + cbe = get_cbe(GRUBASE(cb), cbrnum); + gru_flush_cache(cbe); /* CBE not coherent */ + sync_core(); + excdet->opc = cbe->opccpy; + excdet->exopc = cbe->exopccpy; + excdet->ecause = cbe->ecause; + excdet->exceptdet0 = cbe->idef1upd; + excdet->exceptdet1 = cbe->idef3upd; + gru_flush_cache(cbe); + return 0; +} + +static char *gru_get_cb_exception_detail_str(int ret, void *cb, + char *buf, int size) +{ + struct gru_control_block_status *gen = (void *)cb; + struct control_block_extended_exc_detail excdet; + + if (ret > 0 && gen->istatus == CBS_EXCEPTION) { + gru_get_cb_exception_detail(cb, &excdet); + snprintf(buf, size, + "GRU:%d exception: cb %p, opc %d, exopc %d, ecause 0x%x," + "excdet0 0x%lx, excdet1 0x%x", smp_processor_id(), + gen, excdet.opc, excdet.exopc, excdet.ecause, + excdet.exceptdet0, excdet.exceptdet1); + } else { + snprintf(buf, size, "No exception"); + } + return buf; +} + +static int gru_wait_idle_or_exception(struct gru_control_block_status *gen) +{ + while (gen->istatus >= CBS_ACTIVE) { + cpu_relax(); + barrier(); + } + return gen->istatus; +} + +static int gru_retry_exception(void *cb) +{ + struct gru_control_block_status *gen = (void *)cb; + struct control_block_extended_exc_detail excdet; + int retry = EXCEPTION_RETRY_LIMIT; + + while (1) { + if (gru_wait_idle_or_exception(gen) == CBS_IDLE) + return CBS_IDLE; + if (gru_get_cb_message_queue_substatus(cb)) + return CBS_EXCEPTION; + gru_get_cb_exception_detail(cb, &excdet); + if ((excdet.ecause & ~EXCEPTION_RETRY_BITS) || + (excdet.cbrexecstatus & CBR_EXS_ABORT_OCC)) + break; + if (retry-- == 0) + break; + gen->icmd = 1; + gru_flush_cache(gen); + } + return CBS_EXCEPTION; +} + +int gru_check_status_proc(void *cb) +{ + struct gru_control_block_status *gen = (void *)cb; + int ret; + + ret = gen->istatus; + if (ret == CBS_EXCEPTION) + ret = gru_retry_exception(cb); + rmb(); + return ret; + +} + +int gru_wait_proc(void *cb) +{ + struct gru_control_block_status *gen = (void *)cb; + int ret; + + ret = gru_wait_idle_or_exception(gen); + if (ret == CBS_EXCEPTION) + ret = gru_retry_exception(cb); + rmb(); + return ret; +} + +static void gru_abort(int ret, void *cb, char *str) +{ + char buf[GRU_EXC_STR_SIZE]; + + panic("GRU FATAL ERROR: %s - %s\n", str, + gru_get_cb_exception_detail_str(ret, cb, buf, sizeof(buf))); +} + +void gru_wait_abort_proc(void *cb) +{ + int ret; + + ret = gru_wait_proc(cb); + if (ret) + gru_abort(ret, cb, "gru_wait_abort"); +} + + +/*------------------------------ MESSAGE QUEUES -----------------------------*/ + +/* Internal status . These are NOT returned to the user. */ +#define MQIE_AGAIN -1 /* try again */ + + +/* + * Save/restore the "present" flag that is in the second line of 2-line + * messages + */ +static inline int get_present2(void *p) +{ + struct message_header *mhdr = p + GRU_CACHE_LINE_BYTES; + return mhdr->present; +} + +static inline void restore_present2(void *p, int val) +{ + struct message_header *mhdr = p + GRU_CACHE_LINE_BYTES; + mhdr->present = val; +} + +/* + * Create a message queue. + * qlines - message queue size in cache lines. Includes 2-line header. + */ +int gru_create_message_queue(struct gru_message_queue_desc *mqd, + void *p, unsigned int bytes, int nasid, int vector, int apicid) +{ + struct message_queue *mq = p; + unsigned int qlines; + + qlines = bytes / GRU_CACHE_LINE_BYTES - 2; + memset(mq, 0, bytes); + mq->start = &mq->data; + mq->start2 = &mq->data + (qlines / 2 - 1) * GRU_CACHE_LINE_BYTES; + mq->next = &mq->data; + mq->limit = &mq->data + (qlines - 2) * GRU_CACHE_LINE_BYTES; + mq->qlines = qlines; + mq->hstatus[0] = 0; + mq->hstatus[1] = 1; + mq->head = gru_mesq_head(2, qlines / 2 + 1); + mqd->mq = mq; + mqd->mq_gpa = uv_gpa(mq); + mqd->qlines = qlines; + mqd->interrupt_pnode = nasid >> 1; + mqd->interrupt_vector = vector; + mqd->interrupt_apicid = apicid; + return 0; +} +EXPORT_SYMBOL_GPL(gru_create_message_queue); + +/* + * Send a NOOP message to a message queue + * Returns: + * 0 - if queue is full after the send. This is the normal case + * but various races can change this. + * -1 - if mesq sent successfully but queue not full + * >0 - unexpected error. MQE_xxx returned + */ +static int send_noop_message(void *cb, struct gru_message_queue_desc *mqd, + void *mesg) +{ + const struct message_header noop_header = { + .present = MQS_NOOP, .lines = 1}; + unsigned long m; + int substatus, ret; + struct message_header save_mhdr, *mhdr = mesg; + + STAT(mesq_noop); + save_mhdr = *mhdr; + *mhdr = noop_header; + gru_mesq(cb, mqd->mq_gpa, gru_get_tri(mhdr), 1, IMA); + ret = gru_wait(cb); + + if (ret) { + substatus = gru_get_cb_message_queue_substatus(cb); + switch (substatus) { + case CBSS_NO_ERROR: + STAT(mesq_noop_unexpected_error); + ret = MQE_UNEXPECTED_CB_ERR; + break; + case CBSS_LB_OVERFLOWED: + STAT(mesq_noop_lb_overflow); + ret = MQE_CONGESTION; + break; + case CBSS_QLIMIT_REACHED: + STAT(mesq_noop_qlimit_reached); + ret = 0; + break; + case CBSS_AMO_NACKED: + STAT(mesq_noop_amo_nacked); + ret = MQE_CONGESTION; + break; + case CBSS_PUT_NACKED: + STAT(mesq_noop_put_nacked); + m = mqd->mq_gpa + (gru_get_amo_value_head(cb) << 6); + gru_vstore(cb, m, gru_get_tri(mesg), XTYPE_CL, 1, 1, + IMA); + if (gru_wait(cb) == CBS_IDLE) + ret = MQIE_AGAIN; + else + ret = MQE_UNEXPECTED_CB_ERR; + break; + case CBSS_PAGE_OVERFLOW: + STAT(mesq_noop_page_overflow); + /* fallthru */ + default: + BUG(); + } + } + *mhdr = save_mhdr; + return ret; +} + +/* + * Handle a gru_mesq full. + */ +static int send_message_queue_full(void *cb, struct gru_message_queue_desc *mqd, + void *mesg, int lines) +{ + union gru_mesqhead mqh; + unsigned int limit, head; + unsigned long avalue; + int half, qlines; + + /* Determine if switching to first/second half of q */ + avalue = gru_get_amo_value(cb); + head = gru_get_amo_value_head(cb); + limit = gru_get_amo_value_limit(cb); + + qlines = mqd->qlines; + half = (limit != qlines); + + if (half) + mqh = gru_mesq_head(qlines / 2 + 1, qlines); + else + mqh = gru_mesq_head(2, qlines / 2 + 1); + + /* Try to get lock for switching head pointer */ + gru_gamir(cb, EOP_IR_CLR, HSTATUS(mqd->mq_gpa, half), XTYPE_DW, IMA); + if (gru_wait(cb) != CBS_IDLE) + goto cberr; + if (!gru_get_amo_value(cb)) { + STAT(mesq_qf_locked); + return MQE_QUEUE_FULL; + } + + /* Got the lock. Send optional NOP if queue not full, */ + if (head != limit) { + if (send_noop_message(cb, mqd, mesg)) { + gru_gamir(cb, EOP_IR_INC, HSTATUS(mqd->mq_gpa, half), + XTYPE_DW, IMA); + if (gru_wait(cb) != CBS_IDLE) + goto cberr; + STAT(mesq_qf_noop_not_full); + return MQIE_AGAIN; + } + avalue++; + } + + /* Then flip queuehead to other half of queue. */ + gru_gamer(cb, EOP_ERR_CSWAP, mqd->mq_gpa, XTYPE_DW, mqh.val, avalue, + IMA); + if (gru_wait(cb) != CBS_IDLE) + goto cberr; + + /* If not successfully in swapping queue head, clear the hstatus lock */ + if (gru_get_amo_value(cb) != avalue) { + STAT(mesq_qf_switch_head_failed); + gru_gamir(cb, EOP_IR_INC, HSTATUS(mqd->mq_gpa, half), XTYPE_DW, + IMA); + if (gru_wait(cb) != CBS_IDLE) + goto cberr; + } + return MQIE_AGAIN; +cberr: + STAT(mesq_qf_unexpected_error); + return MQE_UNEXPECTED_CB_ERR; +} + +/* + * Handle a PUT failure. Note: if message was a 2-line message, one of the + * lines might have successfully have been written. Before sending the + * message, "present" must be cleared in BOTH lines to prevent the receiver + * from prematurely seeing the full message. + */ +static int send_message_put_nacked(void *cb, struct gru_message_queue_desc *mqd, + void *mesg, int lines) +{ + unsigned long m; + int ret, loops = 200; /* experimentally determined */ + + m = mqd->mq_gpa + (gru_get_amo_value_head(cb) << 6); + if (lines == 2) { + gru_vset(cb, m, 0, XTYPE_CL, lines, 1, IMA); + if (gru_wait(cb) != CBS_IDLE) + return MQE_UNEXPECTED_CB_ERR; + } + gru_vstore(cb, m, gru_get_tri(mesg), XTYPE_CL, lines, 1, IMA); + if (gru_wait(cb) != CBS_IDLE) + return MQE_UNEXPECTED_CB_ERR; + + if (!mqd->interrupt_vector) + return MQE_OK; + + /* + * Send a noop message in order to deliver a cross-partition interrupt + * to the SSI that contains the target message queue. Normally, the + * interrupt is automatically delivered by hardware following mesq + * operations, but some error conditions require explicit delivery. + * The noop message will trigger delivery. Otherwise partition failures + * could cause unrecovered errors. + */ + do { + ret = send_noop_message(cb, mqd, mesg); + } while ((ret == MQIE_AGAIN || ret == MQE_CONGESTION) && (loops-- > 0)); + + if (ret == MQIE_AGAIN || ret == MQE_CONGESTION) { + /* + * Don't indicate to the app to resend the message, as it's + * already been successfully sent. We simply send an OK + * (rather than fail the send with MQE_UNEXPECTED_CB_ERR), + * assuming that the other side is receiving enough + * interrupts to get this message processed anyway. + */ + ret = MQE_OK; + } + return ret; +} + +/* + * Handle a gru_mesq failure. Some of these failures are software recoverable + * or retryable. + */ +static int send_message_failure(void *cb, struct gru_message_queue_desc *mqd, + void *mesg, int lines) +{ + int substatus, ret = 0; + + substatus = gru_get_cb_message_queue_substatus(cb); + switch (substatus) { + case CBSS_NO_ERROR: + STAT(mesq_send_unexpected_error); + ret = MQE_UNEXPECTED_CB_ERR; + break; + case CBSS_LB_OVERFLOWED: + STAT(mesq_send_lb_overflow); + ret = MQE_CONGESTION; + break; + case CBSS_QLIMIT_REACHED: + STAT(mesq_send_qlimit_reached); + ret = send_message_queue_full(cb, mqd, mesg, lines); + break; + case CBSS_AMO_NACKED: + STAT(mesq_send_amo_nacked); + ret = MQE_CONGESTION; + break; + case CBSS_PUT_NACKED: + STAT(mesq_send_put_nacked); + ret = send_message_put_nacked(cb, mqd, mesg, lines); + break; + case CBSS_PAGE_OVERFLOW: + STAT(mesq_page_overflow); + /* fallthru */ + default: + BUG(); + } + return ret; +} + +/* + * Send a message to a message queue + * mqd message queue descriptor + * mesg message. ust be vaddr within a GSEG + * bytes message size (<= 2 CL) + */ +int gru_send_message_gpa(struct gru_message_queue_desc *mqd, void *mesg, + unsigned int bytes) +{ + struct message_header *mhdr; + void *cb; + void *dsr; + int istatus, clines, ret; + + STAT(mesq_send); + BUG_ON(bytes < sizeof(int) || bytes > 2 * GRU_CACHE_LINE_BYTES); + + clines = DIV_ROUND_UP(bytes, GRU_CACHE_LINE_BYTES); + if (gru_get_cpu_resources(bytes, &cb, &dsr)) + return MQE_BUG_NO_RESOURCES; + memcpy(dsr, mesg, bytes); + mhdr = dsr; + mhdr->present = MQS_FULL; + mhdr->lines = clines; + if (clines == 2) { + mhdr->present2 = get_present2(mhdr); + restore_present2(mhdr, MQS_FULL); + } + + do { + ret = MQE_OK; + gru_mesq(cb, mqd->mq_gpa, gru_get_tri(mhdr), clines, IMA); + istatus = gru_wait(cb); + if (istatus != CBS_IDLE) + ret = send_message_failure(cb, mqd, dsr, clines); + } while (ret == MQIE_AGAIN); + gru_free_cpu_resources(cb, dsr); + + if (ret) + STAT(mesq_send_failed); + return ret; +} +EXPORT_SYMBOL_GPL(gru_send_message_gpa); + +/* + * Advance the receive pointer for the queue to the next message. + */ +void gru_free_message(struct gru_message_queue_desc *mqd, void *mesg) +{ + struct message_queue *mq = mqd->mq; + struct message_header *mhdr = mq->next; + void *next, *pnext; + int half = -1; + int lines = mhdr->lines; + + if (lines == 2) + restore_present2(mhdr, MQS_EMPTY); + mhdr->present = MQS_EMPTY; + + pnext = mq->next; + next = pnext + GRU_CACHE_LINE_BYTES * lines; + if (next == mq->limit) { + next = mq->start; + half = 1; + } else if (pnext < mq->start2 && next >= mq->start2) { + half = 0; + } + + if (half >= 0) + mq->hstatus[half] = 1; + mq->next = next; +} +EXPORT_SYMBOL_GPL(gru_free_message); + +/* + * Get next message from message queue. Return NULL if no message + * present. User must call next_message() to move to next message. + * rmq message queue + */ +void *gru_get_next_message(struct gru_message_queue_desc *mqd) +{ + struct message_queue *mq = mqd->mq; + struct message_header *mhdr = mq->next; + int present = mhdr->present; + + /* skip NOOP messages */ + while (present == MQS_NOOP) { + gru_free_message(mqd, mhdr); + mhdr = mq->next; + present = mhdr->present; + } + + /* Wait for both halves of 2 line messages */ + if (present == MQS_FULL && mhdr->lines == 2 && + get_present2(mhdr) == MQS_EMPTY) + present = MQS_EMPTY; + + if (!present) { + STAT(mesq_receive_none); + return NULL; + } + + if (mhdr->lines == 2) + restore_present2(mhdr, mhdr->present2); + + STAT(mesq_receive); + return mhdr; +} +EXPORT_SYMBOL_GPL(gru_get_next_message); + +/* ---------------------- GRU DATA COPY FUNCTIONS ---------------------------*/ + +/* + * Load a DW from a global GPA. The GPA can be a memory or MMR address. + */ +int gru_read_gpa(unsigned long *value, unsigned long gpa) +{ + void *cb; + void *dsr; + int ret, iaa; + + STAT(read_gpa); + if (gru_get_cpu_resources(GRU_NUM_KERNEL_DSR_BYTES, &cb, &dsr)) + return MQE_BUG_NO_RESOURCES; + iaa = gpa >> 62; + gru_vload_phys(cb, gpa, gru_get_tri(dsr), iaa, IMA); + ret = gru_wait(cb); + if (ret == CBS_IDLE) + *value = *(unsigned long *)dsr; + gru_free_cpu_resources(cb, dsr); + return ret; +} +EXPORT_SYMBOL_GPL(gru_read_gpa); + + +/* + * Copy a block of data using the GRU resources + */ +int gru_copy_gpa(unsigned long dest_gpa, unsigned long src_gpa, + unsigned int bytes) +{ + void *cb; + void *dsr; + int ret; + + STAT(copy_gpa); + if (gru_get_cpu_resources(GRU_NUM_KERNEL_DSR_BYTES, &cb, &dsr)) + return MQE_BUG_NO_RESOURCES; + gru_bcopy(cb, src_gpa, dest_gpa, gru_get_tri(dsr), + XTYPE_B, bytes, GRU_NUM_KERNEL_DSR_CL, IMA); + ret = gru_wait(cb); + gru_free_cpu_resources(cb, dsr); + return ret; +} +EXPORT_SYMBOL_GPL(gru_copy_gpa); + +/* ------------------- KERNEL QUICKTESTS RUN AT STARTUP ----------------*/ +/* Temp - will delete after we gain confidence in the GRU */ + +static int quicktest0(unsigned long arg) +{ + unsigned long word0; + unsigned long word1; + void *cb; + void *dsr; + unsigned long *p; + int ret = -EIO; + + if (gru_get_cpu_resources(GRU_CACHE_LINE_BYTES, &cb, &dsr)) + return MQE_BUG_NO_RESOURCES; + p = dsr; + word0 = MAGIC; + word1 = 0; + + gru_vload(cb, uv_gpa(&word0), gru_get_tri(dsr), XTYPE_DW, 1, 1, IMA); + if (gru_wait(cb) != CBS_IDLE) { + printk(KERN_DEBUG "GRU:%d quicktest0: CBR failure 1\n", smp_processor_id()); + goto done; + } + + if (*p != MAGIC) { + printk(KERN_DEBUG "GRU:%d quicktest0 bad magic 0x%lx\n", smp_processor_id(), *p); + goto done; + } + gru_vstore(cb, uv_gpa(&word1), gru_get_tri(dsr), XTYPE_DW, 1, 1, IMA); + if (gru_wait(cb) != CBS_IDLE) { + printk(KERN_DEBUG "GRU:%d quicktest0: CBR failure 2\n", smp_processor_id()); + goto done; + } + + if (word0 != word1 || word1 != MAGIC) { + printk(KERN_DEBUG + "GRU:%d quicktest0 err: found 0x%lx, expected 0x%lx\n", + smp_processor_id(), word1, MAGIC); + goto done; + } + ret = 0; + +done: + gru_free_cpu_resources(cb, dsr); + return ret; +} + +#define ALIGNUP(p, q) ((void *)(((unsigned long)(p) + (q) - 1) & ~(q - 1))) + +static int quicktest1(unsigned long arg) +{ + struct gru_message_queue_desc mqd; + void *p, *mq; + int i, ret = -EIO; + char mes[GRU_CACHE_LINE_BYTES], *m; + + /* Need 1K cacheline aligned that does not cross page boundary */ + p = kmalloc(4096, 0); + if (p == NULL) + return -ENOMEM; + mq = ALIGNUP(p, 1024); + memset(mes, 0xee, sizeof(mes)); + + gru_create_message_queue(&mqd, mq, 8 * GRU_CACHE_LINE_BYTES, 0, 0, 0); + for (i = 0; i < 6; i++) { + mes[8] = i; + do { + ret = gru_send_message_gpa(&mqd, mes, sizeof(mes)); + } while (ret == MQE_CONGESTION); + if (ret) + break; + } + if (ret != MQE_QUEUE_FULL || i != 4) { + printk(KERN_DEBUG "GRU:%d quicktest1: unexpect status %d, i %d\n", + smp_processor_id(), ret, i); + goto done; + } + + for (i = 0; i < 6; i++) { + m = gru_get_next_message(&mqd); + if (!m || m[8] != i) + break; + gru_free_message(&mqd, m); + } + if (i != 4) { + printk(KERN_DEBUG "GRU:%d quicktest2: bad message, i %d, m %p, m8 %d\n", + smp_processor_id(), i, m, m ? m[8] : -1); + goto done; + } + ret = 0; + +done: + kfree(p); + return ret; +} + +static int quicktest2(unsigned long arg) +{ + static DECLARE_COMPLETION(cmp); + unsigned long han; + int blade_id = 0; + int numcb = 4; + int ret = 0; + unsigned long *buf; + void *cb0, *cb; + struct gru_control_block_status *gen; + int i, k, istatus, bytes; + + bytes = numcb * 4 * 8; + buf = kmalloc(bytes, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + ret = -EBUSY; + han = gru_reserve_async_resources(blade_id, numcb, 0, &cmp); + if (!han) + goto done; + + gru_lock_async_resource(han, &cb0, NULL); + memset(buf, 0xee, bytes); + for (i = 0; i < numcb; i++) + gru_vset(cb0 + i * GRU_HANDLE_STRIDE, uv_gpa(&buf[i * 4]), 0, + XTYPE_DW, 4, 1, IMA_INTERRUPT); + + ret = 0; + k = numcb; + do { + gru_wait_async_cbr(han); + for (i = 0; i < numcb; i++) { + cb = cb0 + i * GRU_HANDLE_STRIDE; + istatus = gru_check_status(cb); + if (istatus != CBS_ACTIVE && istatus != CBS_CALL_OS) + break; + } + if (i == numcb) + continue; + if (istatus != CBS_IDLE) { + printk(KERN_DEBUG "GRU:%d quicktest2: cb %d, exception\n", smp_processor_id(), i); + ret = -EFAULT; + } else if (buf[4 * i] || buf[4 * i + 1] || buf[4 * i + 2] || + buf[4 * i + 3]) { + printk(KERN_DEBUG "GRU:%d quicktest2:cb %d, buf 0x%lx, 0x%lx, 0x%lx, 0x%lx\n", + smp_processor_id(), i, buf[4 * i], buf[4 * i + 1], buf[4 * i + 2], buf[4 * i + 3]); + ret = -EIO; + } + k--; + gen = cb; + gen->istatus = CBS_CALL_OS; /* don't handle this CBR again */ + } while (k); + BUG_ON(cmp.done); + + gru_unlock_async_resource(han); + gru_release_async_resources(han); +done: + kfree(buf); + return ret; +} + +#define BUFSIZE 200 +static int quicktest3(unsigned long arg) +{ + char buf1[BUFSIZE], buf2[BUFSIZE]; + int ret = 0; + + memset(buf2, 0, sizeof(buf2)); + memset(buf1, get_cycles() & 255, sizeof(buf1)); + gru_copy_gpa(uv_gpa(buf2), uv_gpa(buf1), BUFSIZE); + if (memcmp(buf1, buf2, BUFSIZE)) { + printk(KERN_DEBUG "GRU:%d quicktest3 error\n", smp_processor_id()); + ret = -EIO; + } + return ret; +} + +/* + * Debugging only. User hook for various kernel tests + * of driver & gru. + */ +int gru_ktest(unsigned long arg) +{ + int ret = -EINVAL; + + switch (arg & 0xff) { + case 0: + ret = quicktest0(arg); + break; + case 1: + ret = quicktest1(arg); + break; + case 2: + ret = quicktest2(arg); + break; + case 3: + ret = quicktest3(arg); + break; + case 99: + ret = gru_free_kernel_contexts(); + break; + } + return ret; + +} + +int gru_kservices_init(void) +{ + return 0; +} + +void gru_kservices_exit(void) +{ + if (gru_free_kernel_contexts()) + BUG(); +} + |