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-rw-r--r--drivers/misc/sgi-gru/gruhandles.c5
-rw-r--r--drivers/misc/sgi-gru/grukdump.c2
-rw-r--r--drivers/misc/sgi-gru/grukservices.c201
-rw-r--r--drivers/misc/sgi-gru/grumain.c55
-rw-r--r--drivers/misc/sgi-gru/gruprocfs.c9
-rw-r--r--drivers/misc/sgi-gru/grutables.h17
6 files changed, 184 insertions, 105 deletions
diff --git a/drivers/misc/sgi-gru/gruhandles.c b/drivers/misc/sgi-gru/gruhandles.c
index a3a870ad9153..37e7cfc53b9c 100644
--- a/drivers/misc/sgi-gru/gruhandles.c
+++ b/drivers/misc/sgi-gru/gruhandles.c
@@ -57,7 +57,7 @@ static void start_instruction(void *h)
static int wait_instruction_complete(void *h, enum mcs_op opc)
{
int status;
- cycles_t start_time = get_cycles();
+ unsigned long start_time = get_cycles();
while (1) {
cpu_relax();
@@ -65,7 +65,8 @@ static int wait_instruction_complete(void *h, enum mcs_op opc)
if (status != CCHSTATUS_ACTIVE)
break;
if (GRU_OPERATION_TIMEOUT < (get_cycles() - start_time))
- panic("GRU %p is malfunctioning\n", h);
+ panic("GRU %p is malfunctioning: start %ld, end %ld\n",
+ h, start_time, (unsigned long)get_cycles());
}
if (gru_options & OPT_STATS)
update_mcs_stats(opc, get_cycles() - start_time);
diff --git a/drivers/misc/sgi-gru/grukdump.c b/drivers/misc/sgi-gru/grukdump.c
index 27e00931a7b8..7b1bdf3906ba 100644
--- a/drivers/misc/sgi-gru/grukdump.c
+++ b/drivers/misc/sgi-gru/grukdump.c
@@ -131,7 +131,7 @@ static int gru_dump_context(struct gru_state *gru, int ctxnum,
if (cch_locked || !lock_cch) {
gts = gru->gs_gts[ctxnum];
- if (gts) {
+ if (gts && gts->ts_vma) {
hdr.pid = gts->ts_tgid_owner;
hdr.vaddr = gts->ts_vma->vm_start;
}
diff --git a/drivers/misc/sgi-gru/grukservices.c b/drivers/misc/sgi-gru/grukservices.c
index 900f7aad2286..50b4dd8b0c9f 100644
--- a/drivers/misc/sgi-gru/grukservices.c
+++ b/drivers/misc/sgi-gru/grukservices.c
@@ -31,6 +31,7 @@
#include <linux/proc_fs.h>
#include <linux/interrupt.h>
#include <linux/uaccess.h>
+#include <linux/delay.h>
#include "gru.h"
#include "grulib.h"
#include "grutables.h"
@@ -45,18 +46,17 @@
* resources. This will likely be replaced when we better understand the
* kernel/user requirements.
*
- * At boot time, the kernel permanently reserves a fixed number of
- * CBRs/DSRs for each cpu to use. The resources are all taken from
- * the GRU chiplet 1 on the blade. This leaves the full set of resources
- * of chiplet 0 available to be allocated to a single user.
+ * 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!!!.
*/
-
-/* Blade percpu resources PERMANENTLY reserved for kernel use */
#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)
-#define KERNEL_CTXNUM 15
/* GRU instruction attributes for all instructions */
#define IMA IMA_CB_DELAY
@@ -98,6 +98,88 @@ struct message_header {
#define HSTATUS(mq, h) ((mq) + offsetof(struct message_queue, hstatus[h]))
+/*
+ * Allocate a kernel context (GTS) for the specified blade.
+ * - protected by writelock on bs_kgts_sema.
+ */
+static void gru_alloc_kernel_context(struct gru_blade_state *bs, int blade_id)
+{
+ int cbr_au_count, dsr_au_count, ncpus;
+
+ ncpus = uv_blade_nr_possible_cpus(blade_id);
+ cbr_au_count = GRU_CB_COUNT_TO_AU(GRU_NUM_KERNEL_CBR * ncpus);
+ dsr_au_count = GRU_DS_BYTES_TO_AU(GRU_NUM_KERNEL_DSR_BYTES * ncpus);
+ bs->bs_kgts = gru_alloc_gts(NULL, cbr_au_count, dsr_au_count, 0, 0);
+}
+
+/*
+ * 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;
+
+ up_read(&bs->bs_kgts_sema);
+ down_write(&bs->bs_kgts_sema);
+
+ if (!bs->bs_kgts)
+ gru_alloc_kernel_context(bs, blade_id);
+ kgts = bs->bs_kgts;
+
+ if (!kgts->ts_gru) {
+ STAT(load_kernel_context);
+ while (!gru_assign_gru_context(kgts, blade_id)) {
+ msleep(1);
+ gru_steal_context(kgts, blade_id);
+ }
+ 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);
+}
+
+/*
+ * 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;
+
+ STAT(lock_kernel_context);
+ bs = gru_base[blade_id];
+
+ down_read(&bs->bs_kgts_sema);
+ if (!bs->bs_kgts || !bs->bs_kgts->ts_gru)
+ gru_load_kernel_context(bs, blade_id);
+ 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;
@@ -105,18 +187,23 @@ static int gru_get_cpu_resources(int dsr_bytes, void **cb, void **dsr)
BUG_ON(dsr_bytes > GRU_NUM_KERNEL_DSR_BYTES);
preempt_disable();
- bs = gru_base[uv_numa_blade_id()];
+ bs = gru_lock_kernel_context(uv_numa_blade_id());
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();
}
+/*----------------------------------------------------------------------*/
int gru_get_cb_exception_detail(void *cb,
struct control_block_extended_exc_detail *excdet)
{
@@ -597,34 +684,36 @@ EXPORT_SYMBOL_GPL(gru_copy_gpa);
/* ------------------- KERNEL QUICKTESTS RUN AT STARTUP ----------------*/
/* Temp - will delete after we gain confidence in the GRU */
-static __cacheline_aligned unsigned long word0;
-static __cacheline_aligned unsigned long word1;
-static int quicktest(struct gru_state *gru)
+int quicktest(void)
{
+ unsigned long word0;
+ unsigned long word1;
void *cb;
- void *ds;
+ void *dsr;
unsigned long *p;
- cb = get_gseg_base_address_cb(gru->gs_gru_base_vaddr, KERNEL_CTXNUM, 0);
- ds = get_gseg_base_address_ds(gru->gs_gru_base_vaddr, KERNEL_CTXNUM, 0);
- p = ds;
+ 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), 0, XTYPE_DW, 1, 1, IMA);
+ gru_vload(cb, uv_gpa(&word0), gru_get_tri(dsr), XTYPE_DW, 1, 1, IMA);
if (gru_wait(cb) != CBS_IDLE)
BUG();
- if (*(unsigned long *)ds != MAGIC)
+ if (*p != MAGIC)
BUG();
- gru_vstore(cb, uv_gpa(&word1), 0, XTYPE_DW, 1, 1, IMA);
+ gru_vstore(cb, uv_gpa(&word1), gru_get_tri(dsr), XTYPE_DW, 1, 1, IMA);
if (gru_wait(cb) != CBS_IDLE)
BUG();
+ gru_free_cpu_resources(cb, dsr);
- if (word0 != word1 || word0 != MAGIC) {
+ if (word0 != word1 || word1 != MAGIC) {
printk
- ("GRU quicktest err: gid %d, found 0x%lx, expected 0x%lx\n",
- gru->gs_gid, word1, MAGIC);
+ ("GRU quicktest err: found 0x%lx, expected 0x%lx\n",
+ word1, MAGIC);
BUG(); /* ZZZ should not be fatal */
}
@@ -635,80 +724,30 @@ static int quicktest(struct gru_state *gru)
int gru_kservices_init(struct gru_state *gru)
{
struct gru_blade_state *bs;
- struct gru_context_configuration_handle *cch;
- unsigned long cbr_map, dsr_map;
- int err, num, cpus_possible;
-
- /*
- * Currently, resources are reserved ONLY on the second chiplet
- * on each blade. This leaves ALL resources on chiplet 0 available
- * for user code.
- */
+
bs = gru->gs_blade;
- if (gru != &bs->bs_grus[1])
+ if (gru != &bs->bs_grus[0])
return 0;
- cpus_possible = uv_blade_nr_possible_cpus(gru->gs_blade_id);
-
- num = GRU_NUM_KERNEL_CBR * cpus_possible;
- cbr_map = gru_reserve_cb_resources(gru, GRU_CB_COUNT_TO_AU(num), NULL);
- gru->gs_reserved_cbrs += num;
-
- num = GRU_NUM_KERNEL_DSR_BYTES * cpus_possible;
- dsr_map = gru_reserve_ds_resources(gru, GRU_DS_BYTES_TO_AU(num), NULL);
- gru->gs_reserved_dsr_bytes += num;
-
- gru->gs_active_contexts++;
- __set_bit(KERNEL_CTXNUM, &gru->gs_context_map);
- cch = get_cch(gru->gs_gru_base_vaddr, KERNEL_CTXNUM);
-
- bs->kernel_cb = get_gseg_base_address_cb(gru->gs_gru_base_vaddr,
- KERNEL_CTXNUM, 0);
- bs->kernel_dsr = get_gseg_base_address_ds(gru->gs_gru_base_vaddr,
- KERNEL_CTXNUM, 0);
-
- lock_cch_handle(cch);
- cch->tfm_fault_bit_enable = 0;
- cch->tlb_int_enable = 0;
- cch->tfm_done_bit_enable = 0;
- cch->unmap_enable = 1;
- cch->dsr_allocation_map = dsr_map;
- cch->cbr_allocation_map = cbr_map;
-
- err = cch_allocate(cch);
- if (err) {
- gru_dbg(grudev,
- "Unable to allocate kernel CCH: gid %d, err %d\n",
- gru->gs_gid, err);
- BUG();
- }
- if (cch_start(cch)) {
- gru_dbg(grudev, "Unable to start kernel CCH: gid %d, err %d\n",
- gru->gs_gid, err);
- BUG();
- }
- unlock_cch_handle(cch);
+ init_rwsem(&bs->bs_kgts_sema);
if (gru_options & GRU_QUICKLOOK)
- quicktest(gru);
+ quicktest();
return 0;
}
void gru_kservices_exit(struct gru_state *gru)
{
- struct gru_context_configuration_handle *cch;
struct gru_blade_state *bs;
+ struct gru_thread_state *kgts;
bs = gru->gs_blade;
- if (gru != &bs->bs_grus[1])
+ if (gru != &bs->bs_grus[0])
return;
- cch = get_cch(gru->gs_gru_base_vaddr, KERNEL_CTXNUM);
- lock_cch_handle(cch);
- if (cch_interrupt_sync(cch))
- BUG();
- if (cch_deallocate(cch))
- BUG();
- unlock_cch_handle(cch);
+ kgts = bs->bs_kgts;
+ if (kgts && kgts->ts_gru)
+ gru_unload_context(kgts, 0);
+ kfree(kgts);
}
diff --git a/drivers/misc/sgi-gru/grumain.c b/drivers/misc/sgi-gru/grumain.c
index 0c7bd384f0cf..3398e54a762b 100644
--- a/drivers/misc/sgi-gru/grumain.c
+++ b/drivers/misc/sgi-gru/grumain.c
@@ -96,7 +96,7 @@ static int gru_reset_asid_limit(struct gru_state *gru, int asid)
gid = gru->gs_gid;
again:
for (i = 0; i < GRU_NUM_CCH; i++) {
- if (!gru->gs_gts[i])
+ if (!gru->gs_gts[i] || is_kernel_context(gru->gs_gts[i]))
continue;
inuse_asid = gru->gs_gts[i]->ts_gms->ms_asids[gid].mt_asid;
gru_dbg(grudev, "gid %d, gts %p, gms %p, inuse 0x%x, cxt %d\n",
@@ -506,7 +506,8 @@ void gru_unload_context(struct gru_thread_state *gts, int savestate)
struct gru_context_configuration_handle *cch;
int ctxnum = gts->ts_ctxnum;
- zap_vma_ptes(gts->ts_vma, UGRUADDR(gts), GRU_GSEG_PAGESIZE);
+ if (!is_kernel_context(gts))
+ zap_vma_ptes(gts->ts_vma, UGRUADDR(gts), GRU_GSEG_PAGESIZE);
cch = get_cch(gru->gs_gru_base_vaddr, ctxnum);
gru_dbg(grudev, "gts %p\n", gts);
@@ -514,7 +515,8 @@ void gru_unload_context(struct gru_thread_state *gts, int savestate)
if (cch_interrupt_sync(cch))
BUG();
- gru_unload_mm_tracker(gru, gts);
+ if (!is_kernel_context(gts))
+ gru_unload_mm_tracker(gru, gts);
if (savestate)
gru_unload_context_data(gts->ts_gdata, gru->gs_gru_base_vaddr,
ctxnum, gts->ts_cbr_map,
@@ -526,7 +528,6 @@ void gru_unload_context(struct gru_thread_state *gts, int savestate)
unlock_cch_handle(cch);
gru_free_gru_context(gts);
- STAT(unload_context);
}
/*
@@ -554,11 +555,16 @@ void gru_load_context(struct gru_thread_state *gts)
cch->tfm_done_bit_enable = 0;
cch->dsr_allocation_map = gts->ts_dsr_map;
cch->cbr_allocation_map = gts->ts_cbr_map;
- asid = gru_load_mm_tracker(gru, gts);
- cch->unmap_enable = 0;
- for (i = 0; i < 8; i++) {
- cch->asid[i] = asid + i;
- cch->sizeavail[i] = gts->ts_sizeavail;
+
+ if (is_kernel_context(gts)) {
+ cch->unmap_enable = 1;
+ } else {
+ cch->unmap_enable = 0;
+ asid = gru_load_mm_tracker(gru, gts);
+ for (i = 0; i < 8; i++) {
+ cch->asid[i] = asid + i;
+ cch->sizeavail[i] = gts->ts_sizeavail;
+ }
}
err = cch_allocate(cch);
@@ -575,8 +581,6 @@ void gru_load_context(struct gru_thread_state *gts)
if (cch_start(cch))
BUG();
unlock_cch_handle(cch);
-
- STAT(load_context);
}
/*
@@ -652,6 +656,27 @@ static int gru_retarget_intr(struct gru_thread_state *gts)
#define next_gru(b, g) (((g) < &(b)->bs_grus[GRU_CHIPLETS_PER_BLADE - 1]) ? \
((g)+1) : &(b)->bs_grus[0])
+static int is_gts_stealable(struct gru_thread_state *gts,
+ struct gru_blade_state *bs)
+{
+ if (is_kernel_context(gts))
+ return down_write_trylock(&bs->bs_kgts_sema);
+ else
+ return mutex_trylock(&gts->ts_ctxlock);
+}
+
+static void gts_stolen(struct gru_thread_state *gts,
+ struct gru_blade_state *bs)
+{
+ if (is_kernel_context(gts)) {
+ up_write(&bs->bs_kgts_sema);
+ STAT(steal_kernel_context);
+ } else {
+ mutex_unlock(&gts->ts_ctxlock);
+ STAT(steal_user_context);
+ }
+}
+
void gru_steal_context(struct gru_thread_state *gts, int blade_id)
{
struct gru_blade_state *blade;
@@ -685,7 +710,7 @@ void gru_steal_context(struct gru_thread_state *gts, int blade_id)
* success are high. If trylock fails, try to steal a
* different GSEG.
*/
- if (ngts && mutex_trylock(&ngts->ts_ctxlock))
+ if (ngts && is_gts_stealable(ngts, blade))
break;
ngts = NULL;
flag = 1;
@@ -701,10 +726,9 @@ void gru_steal_context(struct gru_thread_state *gts, int blade_id)
spin_unlock(&blade->bs_lock);
if (ngts) {
- STAT(steal_context);
ngts->ts_steal_jiffies = jiffies;
- gru_unload_context(ngts, 1);
- mutex_unlock(&ngts->ts_ctxlock);
+ gru_unload_context(ngts, is_kernel_context(ngts) ? 0 : 1);
+ gts_stolen(ngts, blade);
} else {
STAT(steal_context_failed);
}
@@ -810,6 +834,7 @@ again:
}
if (!gts->ts_gru) {
+ STAT(load_user_context);
if (!gru_assign_gru_context(gts, blade_id)) {
preempt_enable();
mutex_unlock(&gts->ts_ctxlock);
diff --git a/drivers/misc/sgi-gru/gruprocfs.c b/drivers/misc/sgi-gru/gruprocfs.c
index c46c1c5f0c73..6ef4cb4b84c8 100644
--- a/drivers/misc/sgi-gru/gruprocfs.c
+++ b/drivers/misc/sgi-gru/gruprocfs.c
@@ -51,9 +51,12 @@ static int statistics_show(struct seq_file *s, void *p)
printstat(s, assign_context);
printstat(s, assign_context_failed);
printstat(s, free_context);
- printstat(s, load_context);
- printstat(s, unload_context);
- printstat(s, steal_context);
+ printstat(s, load_user_context);
+ printstat(s, load_kernel_context);
+ printstat(s, lock_kernel_context);
+ printstat(s, unlock_kernel_context);
+ printstat(s, steal_user_context);
+ printstat(s, steal_kernel_context);
printstat(s, steal_context_failed);
printstat(s, nopfn);
printstat(s, break_cow);
diff --git a/drivers/misc/sgi-gru/grutables.h b/drivers/misc/sgi-gru/grutables.h
index 4ddb5b92acbb..1c85fdcf5d37 100644
--- a/drivers/misc/sgi-gru/grutables.h
+++ b/drivers/misc/sgi-gru/grutables.h
@@ -174,9 +174,12 @@ struct gru_stats_s {
atomic_long_t assign_context;
atomic_long_t assign_context_failed;
atomic_long_t free_context;
- atomic_long_t load_context;
- atomic_long_t unload_context;
- atomic_long_t steal_context;
+ atomic_long_t load_user_context;
+ atomic_long_t load_kernel_context;
+ atomic_long_t lock_kernel_context;
+ atomic_long_t unlock_kernel_context;
+ atomic_long_t steal_user_context;
+ atomic_long_t steal_kernel_context;
atomic_long_t steal_context_failed;
atomic_long_t nopfn;
atomic_long_t break_cow;
@@ -454,6 +457,9 @@ struct gru_blade_state {
reserved cb */
void *kernel_dsr; /* First kernel
reserved DSR */
+ struct rw_semaphore bs_kgts_sema; /* lock for kgts */
+ struct gru_thread_state *bs_kgts; /* GTS for kernel use */
+
/* ---- the following are protected by the bs_lock spinlock ---- */
spinlock_t bs_lock; /* lock used for
stealing contexts */
@@ -597,6 +603,11 @@ static inline void unlock_tgh_handle(struct gru_tlb_global_handle *tgh)
__unlock_handle(tgh);
}
+static inline int is_kernel_context(struct gru_thread_state *gts)
+{
+ return !gts->ts_mm;
+}
+
/*-----------------------------------------------------------------------------
* Function prototypes & externs
*/
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-11 06:37:52 +0000