ehca_irq.c
/*
* IBM eServer eHCA Infiniband device driver for Linux on POWER
*
* Functions for EQs, NEQs and interrupts
*
* Authors: Heiko J Schick <schickhj@de.ibm.com>
* Khadija Souissi <souissi@de.ibm.com>
* Hoang-Nam Nguyen <hnguyen@de.ibm.com>
* Joachim Fenkes <fenkes@de.ibm.com>
*
* Copyright (c) 2005 IBM Corporation
*
* All rights reserved.
*
* This source code is distributed under a dual license of GPL v2.0 and OpenIB
* BSD.
*
* OpenIB BSD License
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials
* provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
* IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include "ehca_classes.h"
#include "ehca_irq.h"
#include "ehca_iverbs.h"
#include "ehca_tools.h"
#include "hcp_if.h"
#include "hipz_fns.h"
#include "ipz_pt_fn.h"
#define EQE_COMPLETION_EVENT EHCA_BMASK_IBM( 1, 1)
#define EQE_CQ_QP_NUMBER EHCA_BMASK_IBM( 8, 31)
#define EQE_EE_IDENTIFIER EHCA_BMASK_IBM( 2, 7)
#define EQE_CQ_NUMBER EHCA_BMASK_IBM( 8, 31)
#define EQE_QP_NUMBER EHCA_BMASK_IBM( 8, 31)
#define EQE_QP_TOKEN EHCA_BMASK_IBM(32, 63)
#define EQE_CQ_TOKEN EHCA_BMASK_IBM(32, 63)
#define NEQE_COMPLETION_EVENT EHCA_BMASK_IBM( 1, 1)
#define NEQE_EVENT_CODE EHCA_BMASK_IBM( 2, 7)
#define NEQE_PORT_NUMBER EHCA_BMASK_IBM( 8, 15)
#define NEQE_PORT_AVAILABILITY EHCA_BMASK_IBM(16, 16)
#define NEQE_DISRUPTIVE EHCA_BMASK_IBM(16, 16)
#define NEQE_SPECIFIC_EVENT EHCA_BMASK_IBM(16, 23)
#define ERROR_DATA_LENGTH EHCA_BMASK_IBM(52, 63)
#define ERROR_DATA_TYPE EHCA_BMASK_IBM( 0, 7)
static void queue_comp_task(struct ehca_cq *__cq);
static struct ehca_comp_pool *pool;
static inline void comp_event_callback(struct ehca_cq *cq)
{
if (!cq->ib_cq.comp_handler)
return;
spin_lock(&cq->cb_lock);
cq->ib_cq.comp_handler(&cq->ib_cq, cq->ib_cq.cq_context);
spin_unlock(&cq->cb_lock);
return;
}
static void print_error_data(struct ehca_shca *shca, void *data,
u64 *rblock, int length)
{
u64 type = EHCA_BMASK_GET(ERROR_DATA_TYPE, rblock[2]);
u64 resource = rblock[1];
switch (type) {
case 0x1: /* Queue Pair */
{
struct ehca_qp *qp = (struct ehca_qp *)data;
/* only print error data if AER is set */
if (rblock[6] == 0)
return;
ehca_err(&shca->ib_device,
"QP 0x%x (resource=%llx) has errors.",
qp->ib_qp.qp_num, resource);
break;
}
case 0x4: /* Completion Queue */
{
struct ehca_cq *cq = (struct ehca_cq *)data;
ehca_err(&shca->ib_device,
"CQ 0x%x (resource=%llx) has errors.",
cq->cq_number, resource);
break;
}
default:
ehca_err(&shca->ib_device,
"Unknown error type: %llx on %s.",
type, shca->ib_device.name);
break;
}
ehca_err(&shca->ib_device, "Error data is available: %llx.", resource);
ehca_err(&shca->ib_device, "EHCA ----- error data begin "
"---------------------------------------------------");
ehca_dmp(rblock, length, "resource=%llx", resource);
ehca_err(&shca->ib_device, "EHCA ----- error data end "
"----------------------------------------------------");
return;
}
int ehca_error_data(struct ehca_shca *shca, void *data,
u64 resource)
{
unsigned long ret;
u64 *rblock;
unsigned long block_count;
rblock = ehca_alloc_fw_ctrlblock(GFP_ATOMIC);
if (!rblock) {
ehca_err(&shca->ib_device, "Cannot allocate rblock memory.");
ret = -ENOMEM;
goto error_data1;
}
/* rblock must be 4K aligned and should be 4K large */
ret = hipz_h_error_data(shca->ipz_hca_handle,
resource,
rblock,
&block_count);
if (ret == H_R_STATE)
ehca_err(&shca->ib_device,
"No error data is available: %llx.", resource);
else if (ret == H_SUCCESS) {
int length;
length = EHCA_BMASK_GET(ERROR_DATA_LENGTH, rblock[0]);
if (length > EHCA_PAGESIZE)
length = EHCA_PAGESIZE;
print_error_data(shca, data, rblock, length);
} else
ehca_err(&shca->ib_device,
"Error data could not be fetched: %llx", resource);
ehca_free_fw_ctrlblock(rblock);
error_data1:
return ret;
}
static void dispatch_qp_event(struct ehca_shca *shca, struct ehca_qp *qp,
enum ib_event_type event_type)
{
struct ib_event event;
/* PATH_MIG without the QP ever having been armed is false alarm */
if (event_type == IB_EVENT_PATH_MIG && !qp->mig_armed)
return;
event.device = &shca->ib_device;
event.event = event_type;
if (qp->ext_type == EQPT_SRQ) {
if (!qp->ib_srq.event_handler)
return;
event.element.srq = &qp->ib_srq;
qp->ib_srq.event_handler(&event, qp->ib_srq.srq_context);
} else {
if (!qp->ib_qp.event_handler)
return;
event.element.qp = &qp->ib_qp;
qp->ib_qp.event_handler(&event, qp->ib_qp.qp_context);
}
}
static void qp_event_callback(struct ehca_shca *shca, u64 eqe,
enum ib_event_type event_type, int fatal)
{
struct ehca_qp *qp;
u32 token = EHCA_BMASK_GET(EQE_QP_TOKEN, eqe);
read_lock(&ehca_qp_idr_lock);
qp = idr_find(&ehca_qp_idr, token);
if (qp)
atomic_inc(&qp->nr_events);
read_unlock(&ehca_qp_idr_lock);
if (!qp)
return;
if (fatal)
ehca_error_data(shca, qp, qp->ipz_qp_handle.handle);
dispatch_qp_event(shca, qp, fatal && qp->ext_type == EQPT_SRQ ?
IB_EVENT_SRQ_ERR : event_type);
/*
* eHCA only processes one WQE at a time for SRQ base QPs,
* so the last WQE has been processed as soon as the QP enters
* error state.
*/
if (fatal && qp->ext_type == EQPT_SRQBASE)
dispatch_qp_event(shca, qp, IB_EVENT_QP_LAST_WQE_REACHED);
if (atomic_dec_and_test(&qp->nr_events))
wake_up(&qp->wait_completion);
return;
}
static void cq_event_callback(struct ehca_shca *shca,
u64 eqe)
{
struct ehca_cq *cq;
u32 token = EHCA_BMASK_GET(EQE_CQ_TOKEN, eqe);
read_lock(&ehca_cq_idr_lock);
cq = idr_find(&ehca_cq_idr, token);
if (cq)
atomic_inc(&cq->nr_events);
read_unlock(&ehca_cq_idr_lock);
if (!cq)
return;
ehca_error_data(shca, cq, cq->ipz_cq_handle.handle);
if (atomic_dec_and_test(&cq->nr_events))
wake_up(&cq->wait_completion);
return;
}
static void parse_identifier(struct ehca_shca *shca, u64 eqe)
{
u8 identifier = EHCA_BMASK_GET(EQE_EE_IDENTIFIER, eqe);
switch (identifier) {
case 0x02: /* path migrated */
qp_event_callback(shca, eqe, IB_EVENT_PATH_MIG, 0);
break;
case 0x03: /* communication established */
qp_event_callback(shca, eqe, IB_EVENT_COMM_EST, 0);
break;
case 0x04: /* send queue drained */
qp_event_callback(shca, eqe, IB_EVENT_SQ_DRAINED, 0);
break;
case 0x05: /* QP error */
case 0x06: /* QP error */
qp_event_callback(shca, eqe, IB_EVENT_QP_FATAL, 1);
break;
case 0x07: /* CQ error */
case 0x08: /* CQ error */
cq_event_callback(shca, eqe);
break;
case 0x09: /* MRMWPTE error */
ehca_err(&shca->ib_device, "MRMWPTE error.");
break;
case 0x0A: /* port event */
ehca_err(&shca->ib_device, "Port event.");
break;
case 0x0B: /* MR access error */
ehca_err(&shca->ib_device, "MR access error.");
break;
case 0x0C: /* EQ error */
ehca_err(&shca->ib_device, "EQ error.");
break;
case 0x0D: /* P/Q_Key mismatch */
ehca_err(&shca->ib_device, "P/Q_Key mismatch.");
break;
case 0x10: /* sampling complete */
ehca_err(&shca->ib_device, "Sampling complete.");
break;
case 0x11: /* unaffiliated access error */
ehca_err(&shca->ib_device, "Unaffiliated access error.");
break;
case 0x12: /* path migrating */
ehca_err(&shca->ib_device, "Path migrating.");
break;
case 0x13: /* interface trace stopped */
ehca_err(&shca->ib_device, "Interface trace stopped.");
break;
case 0x14: /* first error capture info available */
ehca_info(&shca->ib_device, "First error capture available");
break;
case 0x15: /* SRQ limit reached */
qp_event_callback(shca, eqe, IB_EVENT_SRQ_LIMIT_REACHED, 0);
break;
default:
ehca_err(&shca->ib_device, "Unknown identifier: %x on %s.",
identifier, shca->ib_device.name);
break;
}
return;
}
static void dispatch_port_event(struct ehca_shca *shca, int port_num,
enum ib_event_type type, const char *msg)
{
struct ib_event event;
ehca_info(&shca->ib_device, "port %d %s.", port_num, msg);
event.device = &shca->ib_device;
event.event = type;
event.element.port_num = port_num;
ib_dispatch_event(&event);
}
static void notify_port_conf_change(struct ehca_shca *shca, int port_num)
{
struct ehca_sma_attr new_attr;
struct ehca_sma_attr *old_attr = &shca->sport[port_num - 1].saved_attr;
ehca_query_sma_attr(shca, port_num, &new_attr);
if (new_attr.sm_sl != old_attr->sm_sl ||
new_attr.sm_lid != old_attr->sm_lid)
dispatch_port_event(shca, port_num, IB_EVENT_SM_CHANGE,
"SM changed");
if (new_attr.lid != old_attr->lid ||
new_attr.lmc != old_attr->lmc)
dispatch_port_event(shca, port_num, IB_EVENT_LID_CHANGE,
"LID changed");
if (new_attr.pkey_tbl_len != old_attr->pkey_tbl_len ||
memcmp(new_attr.pkeys, old_attr->pkeys,
sizeof(u16) * new_attr.pkey_tbl_len))
dispatch_port_event(shca, port_num, IB_EVENT_PKEY_CHANGE,
"P_Key changed");
*old_attr = new_attr;
}
/* replay modify_qp for sqps -- return 0 if all is well, 1 if AQP1 destroyed */
static int replay_modify_qp(struct ehca_sport *sport)
{
int aqp1_destroyed;
unsigned long flags;
spin_lock_irqsave(&sport->mod_sqp_lock, flags);
aqp1_destroyed = !sport->ibqp_sqp[IB_QPT_GSI];
if (sport->ibqp_sqp[IB_QPT_SMI])
ehca_recover_sqp(sport->ibqp_sqp[IB_QPT_SMI]);
if (!aqp1_destroyed)
ehca_recover_sqp(sport->ibqp_sqp[IB_QPT_GSI]);
spin_unlock_irqrestore(&sport->mod_sqp_lock, flags);
return aqp1_destroyed;
}
static void parse_ec(struct ehca_shca *shca, u64 eqe)
{
u8 ec = EHCA_BMASK_GET(NEQE_EVENT_CODE, eqe);
u8 port = EHCA_BMASK_GET(NEQE_PORT_NUMBER, eqe);
u8 spec_event;
struct ehca_sport *sport = &shca->sport[port - 1];
switch (ec) {
case 0x30: /* port availability change */
if (EHCA_BMASK_GET(NEQE_PORT_AVAILABILITY, eqe)) {
/* only replay modify_qp calls in autodetect mode;
* if AQP1 was destroyed, the port is already down
* again and we can drop the event.
*/
if (ehca_nr_ports < 0)
if (replay_modify_qp(sport))
break;
sport->port_state = IB_PORT_ACTIVE;
dispatch_port_event(shca, port, IB_EVENT_PORT_ACTIVE,
"is active");
ehca_query_sma_attr(shca, port, &sport->saved_attr);
} else {
sport->port_state = IB_PORT_DOWN;
dispatch_port_event(shca, port, IB_EVENT_PORT_ERR,
"is inactive");
}
break;
case 0x31:
/* port configuration change
* disruptive change is caused by
* LID, PKEY or SM change
*/
if (EHCA_BMASK_GET(NEQE_DISRUPTIVE, eqe)) {
ehca_warn(&shca->ib_device, "disruptive port "
"%d configuration change", port);
sport->port_state = IB_PORT_DOWN;
dispatch_port_event(shca, port, IB_EVENT_PORT_ERR,
"is inactive");
sport->port_state = IB_PORT_ACTIVE;
dispatch_port_event(shca, port, IB_EVENT_PORT_ACTIVE,
"is active");
ehca_query_sma_attr(shca, port,
&sport->saved_attr);
} else
notify_port_conf_change(shca, port);
break;
case 0x32: /* adapter malfunction */
ehca_err(&shca->ib_device, "Adapter malfunction.");
break;
case 0x33: /* trace stopped */
ehca_err(&shca->ib_device, "Traced stopped.");
break;
case 0x34: /* util async event */
spec_event = EHCA_BMASK_GET(NEQE_SPECIFIC_EVENT, eqe);
if (spec_event == 0x80) /* client reregister required */
dispatch_port_event(shca, port,
IB_EVENT_CLIENT_REREGISTER,
"client reregister req.");
else
ehca_warn(&shca->ib_device, "Unknown util async "
"event %x on port %x", spec_event, port);
break;
default:
ehca_err(&shca->ib_device, "Unknown event code: %x on %s.",
ec, shca->ib_device.name);
break;
}
return;
}
static inline void reset_eq_pending(struct ehca_cq *cq)
{
u64 CQx_EP;
struct h_galpa gal = cq->galpas.kernel;
hipz_galpa_store_cq(gal, cqx_ep, 0x0);
CQx_EP = hipz_galpa_load(gal, CQTEMM_OFFSET(cqx_ep));
return;
}
irqreturn_t ehca_interrupt_neq(int irq, void *dev_id)
{
struct ehca_shca *shca = (struct ehca_shca*)dev_id;
tasklet_hi_schedule(&shca->neq.interrupt_task);
return IRQ_HANDLED;
}
void ehca_tasklet_neq(unsigned long data)
{
struct ehca_shca *shca = (struct ehca_shca*)data;
struct ehca_eqe *eqe;
u64 ret;
eqe = ehca_poll_eq(shca, &shca->neq);
while (eqe) {
if (!EHCA_BMASK_GET(NEQE_COMPLETION_EVENT, eqe->entry))
parse_ec(shca, eqe->entry);
eqe = ehca_poll_eq(shca, &shca->neq);
}
ret = hipz_h_reset_event(shca->ipz_hca_handle,
shca->neq.ipz_eq_handle, 0xFFFFFFFFFFFFFFFFL);
if (ret != H_SUCCESS)
ehca_err(&shca->ib_device, "Can't clear notification events.");
return;
}
irqreturn_t ehca_interrupt_eq(int irq, void *dev_id)
{
struct ehca_shca *shca = (struct ehca_shca*)dev_id;
tasklet_hi_schedule(&shca->eq.interrupt_task);
return IRQ_HANDLED;
}
static inline void process_eqe(struct ehca_shca *shca, struct ehca_eqe *eqe)
{
u64 eqe_value;
u32 token;
struct ehca_cq *cq;
eqe_value = eqe->entry;
ehca_dbg(&shca->ib_device, "eqe_value=%llx", eqe_value);
if (EHCA_BMASK_GET(EQE_COMPLETION_EVENT, eqe_value)) {
ehca_dbg(&shca->ib_device, "Got completion event");
token = EHCA_BMASK_GET(EQE_CQ_TOKEN, eqe_value);
read_lock(&ehca_cq_idr_lock);
cq = idr_find(&ehca_cq_idr, token);
if (cq)
atomic_inc(&cq->nr_events);
read_unlock(&ehca_cq_idr_lock);
if (cq == NULL) {
ehca_err(&shca->ib_device,
"Invalid eqe for non-existing cq token=%x",
token);
return;
}
reset_eq_pending(cq);
if (ehca_scaling_code)
queue_comp_task(cq);
else {
comp_event_callback(cq);
if (atomic_dec_and_test(&cq->nr_events))
wake_up(&cq->wait_completion);
}
} else {
ehca_dbg(&shca->ib_device, "Got non completion event");
parse_identifier(shca, eqe_value);
}
}
void ehca_process_eq(struct ehca_shca *shca, int is_irq)
{
struct ehca_eq *eq = &shca->eq;
struct ehca_eqe_cache_entry *eqe_cache = eq->eqe_cache;
u64 eqe_value, ret;
unsigned long flags;
int eqe_cnt, i;
int eq_empty = 0;
spin_lock_irqsave(&eq->irq_spinlock, flags);
if (is_irq) {
const int max_query_cnt = 100;
int query_cnt = 0;
int int_state = 1;
do {
int_state = hipz_h_query_int_state(
shca->ipz_hca_handle, eq->ist);
query_cnt++;
iosync();
} while (int_state && query_cnt < max_query_cnt);
if (unlikely((query_cnt == max_query_cnt)))
ehca_dbg(&shca->ib_device, "int_state=%x query_cnt=%x",
int_state, query_cnt);
}
/* read out all eqes */
eqe_cnt = 0;
do {
u32 token;
eqe_cache[eqe_cnt].eqe = ehca_poll_eq(shca, eq);
if (!eqe_cache[eqe_cnt].eqe)
break;
eqe_value = eqe_cache[eqe_cnt].eqe->entry;
if (EHCA_BMASK_GET(EQE_COMPLETION_EVENT, eqe_value)) {
token = EHCA_BMASK_GET(EQE_CQ_TOKEN, eqe_value);
read_lock(&ehca_cq_idr_lock);
eqe_cache[eqe_cnt].cq = idr_find(&ehca_cq_idr, token);
if (eqe_cache[eqe_cnt].cq)
atomic_inc(&eqe_cache[eqe_cnt].cq->nr_events);
read_unlock(&ehca_cq_idr_lock);
if (!eqe_cache[eqe_cnt].cq) {
ehca_err(&shca->ib_device,
"Invalid eqe for non-existing cq "
"token=%x", token);
continue;
}
} else
eqe_cache[eqe_cnt].cq = NULL;
eqe_cnt++;
} while (eqe_cnt < EHCA_EQE_CACHE_SIZE);
if (!eqe_cnt) {
if (is_irq)
ehca_dbg(&shca->ib_device,
"No eqe found for irq event");
goto unlock_irq_spinlock;
} else if (!is_irq) {
ret = hipz_h_eoi(eq->ist);
if (ret != H_SUCCESS)
ehca_err(&shca->ib_device,
"bad return code EOI -rc = %lld\n", ret);
ehca_dbg(&shca->ib_device, "deadman found %x eqe", eqe_cnt);
}
if (unlikely(eqe_cnt == EHCA_EQE_CACHE_SIZE))
ehca_dbg(&shca->ib_device, "too many eqes for one irq event");
/* enable irq for new packets */
for (i = 0; i < eqe_cnt; i++) {
if (eq->eqe_cache[i].cq)
reset_eq_pending(eq->eqe_cache[i].cq);
}
/* check eq */
spin_lock(&eq->spinlock);
eq_empty = (!ipz_eqit_eq_peek_valid(&shca->eq.ipz_queue));
spin_unlock(&eq->spinlock);
/* call completion handler for cached eqes */
for (i = 0; i < eqe_cnt; i++)
if (eq->eqe_cache[i].cq) {
if (ehca_scaling_code)
queue_comp_task(eq->eqe_cache[i].cq);
else {
struct ehca_cq *cq = eq->eqe_cache[i].cq;
comp_event_callback(cq);
if (atomic_dec_and_test(&cq->nr_events))
wake_up(&cq->wait_completion);
}
} else {
ehca_dbg(&shca->ib_device, "Got non completion event");
parse_identifier(shca, eq->eqe_cache[i].eqe->entry);
}
/* poll eq if not empty */
if (eq_empty)
goto unlock_irq_spinlock;
do {
struct ehca_eqe *eqe;
eqe = ehca_poll_eq(shca, &shca->eq);
if (!eqe)
break;
process_eqe(shca, eqe);
} while (1);
unlock_irq_spinlock:
spin_unlock_irqrestore(&eq->irq_spinlock, flags);
}
void ehca_tasklet_eq(unsigned long data)
{
ehca_process_eq((struct ehca_shca*)data, 1);
}
static inline int find_next_online_cpu(struct ehca_comp_pool *pool)
{
int cpu;
unsigned long flags;
WARN_ON_ONCE(!in_interrupt());
if (ehca_debug_level >= 3)
ehca_dmp(cpu_online_mask, cpumask_size(), "");
spin_lock_irqsave(&pool->last_cpu_lock, flags);
cpu = cpumask_next(pool->last_cpu, cpu_online_mask);
if (cpu >= nr_cpu_ids)
cpu = cpumask_first(cpu_online_mask);
pool->last_cpu = cpu;
spin_unlock_irqrestore(&pool->last_cpu_lock, flags);
return cpu;
}
static void __queue_comp_task(struct ehca_cq *__cq,
struct ehca_cpu_comp_task *cct)
{
unsigned long flags;
spin_lock_irqsave(&cct->task_lock, flags);
spin_lock(&__cq->task_lock);
if (__cq->nr_callbacks == 0) {
__cq->nr_callbacks++;
list_add_tail(&__cq->entry, &cct->cq_list);
cct->cq_jobs++;
wake_up(&cct->wait_queue);
} else
__cq->nr_callbacks++;
spin_unlock(&__cq->task_lock);
spin_unlock_irqrestore(&cct->task_lock, flags);
}
static void queue_comp_task(struct ehca_cq *__cq)
{
int cpu_id;
struct ehca_cpu_comp_task *cct;
int cq_jobs;
unsigned long flags;
cpu_id = find_next_online_cpu(pool);
BUG_ON(!cpu_online(cpu_id));
cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu_id);
BUG_ON(!cct);
spin_lock_irqsave(&cct->task_lock, flags);
cq_jobs = cct->cq_jobs;
spin_unlock_irqrestore(&cct->task_lock, flags);
if (cq_jobs > 0) {
cpu_id = find_next_online_cpu(pool);
cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu_id);
BUG_ON(!cct);
}
__queue_comp_task(__cq, cct);
}
static void run_comp_task(struct ehca_cpu_comp_task *cct)
{
struct ehca_cq *cq;
unsigned long flags;
spin_lock_irqsave(&cct->task_lock, flags);
while (!list_empty(&cct->cq_list)) {
cq = list_entry(cct->cq_list.next, struct ehca_cq, entry);
spin_unlock_irqrestore(&cct->task_lock, flags);
comp_event_callback(cq);
if (atomic_dec_and_test(&cq->nr_events))
wake_up(&cq->wait_completion);
spin_lock_irqsave(&cct->task_lock, flags);
spin_lock(&cq->task_lock);
cq->nr_callbacks--;
if (!cq->nr_callbacks) {
list_del_init(cct->cq_list.next);
cct->cq_jobs--;
}
spin_unlock(&cq->task_lock);
}
spin_unlock_irqrestore(&cct->task_lock, flags);
}
static int comp_task(void *__cct)
{
struct ehca_cpu_comp_task *cct = __cct;
int cql_empty;
DECLARE_WAITQUEUE(wait, current);
set_current_state(TASK_INTERRUPTIBLE);
while (!kthread_should_stop()) {
add_wait_queue(&cct->wait_queue, &wait);
spin_lock_irq(&cct->task_lock);
cql_empty = list_empty(&cct->cq_list);
spin_unlock_irq(&cct->task_lock);
if (cql_empty)
schedule();
else
__set_current_state(TASK_RUNNING);
remove_wait_queue(&cct->wait_queue, &wait);
spin_lock_irq(&cct->task_lock);
cql_empty = list_empty(&cct->cq_list);
spin_unlock_irq(&cct->task_lock);
if (!cql_empty)
run_comp_task(__cct);
set_current_state(TASK_INTERRUPTIBLE);
}
__set_current_state(TASK_RUNNING);
return 0;
}
static struct task_struct *create_comp_task(struct ehca_comp_pool *pool,
int cpu)
{
struct ehca_cpu_comp_task *cct;
cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu);
spin_lock_init(&cct->task_lock);
INIT_LIST_HEAD(&cct->cq_list);
init_waitqueue_head(&cct->wait_queue);
cct->task = kthread_create(comp_task, cct, "ehca_comp/%d", cpu);
return cct->task;
}
static void destroy_comp_task(struct ehca_comp_pool *pool,
int cpu)
{
struct ehca_cpu_comp_task *cct;
struct task_struct *task;
unsigned long flags_cct;
cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu);
spin_lock_irqsave(&cct->task_lock, flags_cct);
task = cct->task;
cct->task = NULL;
cct->cq_jobs = 0;
spin_unlock_irqrestore(&cct->task_lock, flags_cct);
if (task)
kthread_stop(task);
}
static void __cpuinit take_over_work(struct ehca_comp_pool *pool, int cpu)
{
struct ehca_cpu_comp_task *cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu);
LIST_HEAD(list);
struct ehca_cq *cq;
unsigned long flags_cct;
spin_lock_irqsave(&cct->task_lock, flags_cct);
list_splice_init(&cct->cq_list, &list);
while (!list_empty(&list)) {
cq = list_entry(cct->cq_list.next, struct ehca_cq, entry);
list_del(&cq->entry);
__queue_comp_task(cq, per_cpu_ptr(pool->cpu_comp_tasks,
smp_processor_id()));
}
spin_unlock_irqrestore(&cct->task_lock, flags_cct);
}
static int __cpuinit comp_pool_callback(struct notifier_block *nfb,
unsigned long action,
void *hcpu)
{
unsigned int cpu = (unsigned long)hcpu;
struct ehca_cpu_comp_task *cct;
switch (action) {
case CPU_UP_PREPARE:
case CPU_UP_PREPARE_FROZEN:
ehca_gen_dbg("CPU: %x (CPU_PREPARE)", cpu);
if (!create_comp_task(pool, cpu)) {
ehca_gen_err("Can't create comp_task for cpu: %x", cpu);
return NOTIFY_BAD;
}
break;
case CPU_UP_CANCELED:
case CPU_UP_CANCELED_FROZEN:
ehca_gen_dbg("CPU: %x (CPU_CANCELED)", cpu);
cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu);
kthread_bind(cct->task, cpumask_any(cpu_online_mask));
destroy_comp_task(pool, cpu);
break;
case CPU_ONLINE:
case CPU_ONLINE_FROZEN:
ehca_gen_dbg("CPU: %x (CPU_ONLINE)", cpu);
cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu);
kthread_bind(cct->task, cpu);
wake_up_process(cct->task);
break;
case CPU_DOWN_PREPARE:
case CPU_DOWN_PREPARE_FROZEN:
ehca_gen_dbg("CPU: %x (CPU_DOWN_PREPARE)", cpu);
break;
case CPU_DOWN_FAILED:
case CPU_DOWN_FAILED_FROZEN:
ehca_gen_dbg("CPU: %x (CPU_DOWN_FAILED)", cpu);
break;
case CPU_DEAD:
case CPU_DEAD_FROZEN:
ehca_gen_dbg("CPU: %x (CPU_DEAD)", cpu);
destroy_comp_task(pool, cpu);
take_over_work(pool, cpu);
break;
}
return NOTIFY_OK;
}
static struct notifier_block comp_pool_callback_nb __cpuinitdata = {
.notifier_call = comp_pool_callback,
.priority = 0,
};
int ehca_create_comp_pool(void)
{
int cpu;
struct task_struct *task;
if (!ehca_scaling_code)
return 0;
pool = kzalloc(sizeof(struct ehca_comp_pool), GFP_KERNEL);
if (pool == NULL)
return -ENOMEM;
spin_lock_init(&pool->last_cpu_lock);
pool->last_cpu = cpumask_any(cpu_online_mask);
pool->cpu_comp_tasks = alloc_percpu(struct ehca_cpu_comp_task);
if (pool->cpu_comp_tasks == NULL) {
kfree(pool);
return -EINVAL;
}
for_each_online_cpu(cpu) {
task = create_comp_task(pool, cpu);
if (task) {
kthread_bind(task, cpu);
wake_up_process(task);
}
}
register_hotcpu_notifier(&comp_pool_callback_nb);
printk(KERN_INFO "eHCA scaling code enabled\n");
return 0;
}
void ehca_destroy_comp_pool(void)
{
int i;
if (!ehca_scaling_code)
return;
unregister_hotcpu_notifier(&comp_pool_callback_nb);
for_each_online_cpu(i)
destroy_comp_task(pool, i);
free_percpu(pool->cpu_comp_tasks);
kfree(pool);
}
