[tip:x86/uv] x86/uv: Update the UV3 TLB shootdown logic

From: tip-bot for Cliff Wickman
Date: Thu Jun 05 2014 - 10:41:45 EST

Commit-ID: a26fd71953711acb4884df84e393d52de57e4f17
Gitweb: http://git.kernel.org/tip/a26fd71953711acb4884df84e393d52de57e4f17
Author: Cliff Wickman <cpw@xxxxxxx>
AuthorDate: Wed, 14 May 2014 16:15:47 -0500
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Thu, 5 Jun 2014 14:17:20 +0200

x86/uv: Update the UV3 TLB shootdown logic

Update of TLB shootdown code for UV3.

Kernel function native_flush_tlb_others() calls
uv_flush_tlb_others() on UV to invalidate tlb page definitions
on remote cpus. The UV systems have a hardware 'broadcast assist
unit' which can be used to broadcast shootdown messages to all
cpu's of selected nodes.

The behavior of the BAU has changed only slightly with UV3:

- UV3 is recognized with is_uv3_hub().
- UV2 functions and structures (uv2_xxx) are in most cases
simply renamed to uv2_3_xxx.
- Some UV2 error workarounds are not needed for UV3.
(see uv_bau_message_interrupt and enable_timeouts)

Signed-off-by: Cliff Wickman <cpw@xxxxxxx>
Link: http://lkml.kernel.org/r/E1WkgWh-0001yJ-3K@xxxxxxxxxxxxxxxxxxxxxx
[ Removed a few linebreak uglies. ]
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/include/asm/uv/uv_bau.h | 19 ++++++-----
arch/x86/platform/uv/tlb_uv.c | 69 ++++++++++++++++++++++------------------
2 files changed, 49 insertions(+), 39 deletions(-)

diff --git a/arch/x86/include/asm/uv/uv_bau.h b/arch/x86/include/asm/uv/uv_bau.h
index 0b46ef2..2d60a78 100644
--- a/arch/x86/include/asm/uv/uv_bau.h
+++ b/arch/x86/include/asm/uv/uv_bau.h
@@ -73,6 +73,7 @@
#define UV_INTD_SOFT_ACK_TIMEOUT_PERIOD (is_uv1_hub() ? \
UV1_INTD_SOFT_ACK_TIMEOUT_PERIOD : \
UV2_INTD_SOFT_ACK_TIMEOUT_PERIOD)
+/* assuming UV3 is the same */

#define BAU_MISC_CONTROL_MULT_MASK 3

@@ -93,6 +94,8 @@
#define SOFTACK_MSHIFT UVH_LB_BAU_MISC_CONTROL_ENABLE_INTD_SOFT_ACK_MODE_SHFT
#define SOFTACK_PSHIFT UVH_LB_BAU_MISC_CONTROL_INTD_SOFT_ACK_TIMEOUT_PERIOD_SHFT
#define SOFTACK_TIMEOUT_PERIOD UV_INTD_SOFT_ACK_TIMEOUT_PERIOD
+#define PREFETCH_HINT_SHFT UV3H_LB_BAU_MISC_CONTROL_ENABLE_INTD_PREFETCH_HINT_SHFT
+#define SB_STATUS_SHFT UV3H_LB_BAU_MISC_CONTROL_ENABLE_EXTENDED_SB_STATUS_SHFT
#define write_gmmr uv_write_global_mmr64
#define write_lmmr uv_write_local_mmr
#define read_lmmr uv_read_local_mmr
@@ -322,8 +325,9 @@ struct uv1_bau_msg_header {
/*
* UV2 Message header: 16 bytes (128 bits) (bytes 0x30-0x3f of descriptor)
* see figure 9-2 of harp_sys.pdf
+ * assuming UV3 is the same
*/
-struct uv2_bau_msg_header {
+struct uv2_3_bau_msg_header {
unsigned int base_dest_nasid:15; /* nasid of the first bit */
/* bits 14:0 */ /* in uvhub map */
unsigned int dest_subnodeid:5; /* must be 0x10, for the LB */
@@ -395,7 +399,7 @@ struct bau_desc {
*/
union bau_msg_header {
struct uv1_bau_msg_header uv1_hdr;
- struct uv2_bau_msg_header uv2_hdr;
+ struct uv2_3_bau_msg_header uv2_3_hdr;
} header;

struct bau_msg_payload payload;
@@ -631,11 +635,6 @@ struct bau_control {
struct hub_and_pnode *thp;
};

-static inline unsigned long read_mmr_uv2_status(void)
-{
- return read_lmmr(UV2H_LB_BAU_SB_ACTIVATION_STATUS_2);
-}
-
static inline void write_mmr_data_broadcast(int pnode, unsigned long mmr_image)
{
write_gmmr(pnode, UVH_BAU_DATA_BROADCAST, mmr_image);
@@ -760,7 +759,11 @@ static inline int atomic_read_short(const struct atomic_short *v)
*/
static inline int atom_asr(short i, struct atomic_short *v)
{
- return i + xadd(&v->counter, i);
+ short __i = i;
+ asm volatile(LOCK_PREFIX "xaddw %0, %1"
+ : "+r" (i), "+m" (v->counter)
+ : : "memory");
+ return i + __i;
}

/*
diff --git a/arch/x86/platform/uv/tlb_uv.c b/arch/x86/platform/uv/tlb_uv.c
index dfe605a..ed161c6 100644
--- a/arch/x86/platform/uv/tlb_uv.c
+++ b/arch/x86/platform/uv/tlb_uv.c
@@ -1,7 +1,7 @@
/*
* SGI UltraViolet TLB flush routines.
*
- * (c) 2008-2012 Cliff Wickman <cpw@xxxxxxx>, SGI.
+ * (c) 2008-2014 Cliff Wickman <cpw@xxxxxxx>, SGI.
*
* This code is released under the GNU General Public License version 2 or
* later.
@@ -451,7 +451,7 @@ static inline unsigned long long cycles_2_ns(unsigned long long cyc)

/*
* The reverse of the above; converts a duration in ns to a duration in cycles.
- */
+ */
static inline unsigned long long ns_2_cycles(unsigned long long ns)
{
struct cyc2ns_data *data = cyc2ns_read_begin();
@@ -563,7 +563,7 @@ static int uv1_wait_completion(struct bau_desc *bau_desc,
* UV2 could have an extra bit of status in the ACTIVATION_STATUS_2 register.
* But not currently used.
*/
-static unsigned long uv2_read_status(unsigned long offset, int rshft, int desc)
+static unsigned long uv2_3_read_status(unsigned long offset, int rshft, int desc)
{
unsigned long descriptor_status;

@@ -606,7 +606,7 @@ int handle_uv2_busy(struct bau_control *bcp)
return FLUSH_GIVEUP;
}

-static int uv2_wait_completion(struct bau_desc *bau_desc,
+static int uv2_3_wait_completion(struct bau_desc *bau_desc,
unsigned long mmr_offset, int right_shift,
struct bau_control *bcp, long try)
{
@@ -616,7 +616,7 @@ static int uv2_wait_completion(struct bau_desc *bau_desc,
long busy_reps = 0;
struct ptc_stats *stat = bcp->statp;

- descriptor_stat = uv2_read_status(mmr_offset, right_shift, desc);
+ descriptor_stat = uv2_3_read_status(mmr_offset, right_shift, desc);

/* spin on the status MMR, waiting for it to go idle */
while (descriptor_stat != UV2H_DESC_IDLE) {
@@ -658,8 +658,7 @@ static int uv2_wait_completion(struct bau_desc *bau_desc,
/* not to hammer on the clock */
busy_reps = 0;
ttm = get_cycles();
- if ((ttm - bcp->send_message) >
- bcp->timeout_interval)
+ if ((ttm - bcp->send_message) > bcp->timeout_interval)
return handle_uv2_busy(bcp);
}
/*
@@ -667,8 +666,7 @@ static int uv2_wait_completion(struct bau_desc *bau_desc,
*/
cpu_relax();
}
- descriptor_stat = uv2_read_status(mmr_offset, right_shift,
- desc);
+ descriptor_stat = uv2_3_read_status(mmr_offset, right_shift, desc);
}
bcp->conseccompletes++;
return FLUSH_COMPLETE;
@@ -679,8 +677,7 @@ static int uv2_wait_completion(struct bau_desc *bau_desc,
* which register to read and position in that register based on cpu in
* current hub.
*/
-static int wait_completion(struct bau_desc *bau_desc,
- struct bau_control *bcp, long try)
+static int wait_completion(struct bau_desc *bau_desc, struct bau_control *bcp, long try)
{
int right_shift;
unsigned long mmr_offset;
@@ -695,11 +692,9 @@ static int wait_completion(struct bau_desc *bau_desc,
}

if (bcp->uvhub_version == 1)
- return uv1_wait_completion(bau_desc, mmr_offset, right_shift,
- bcp, try);
+ return uv1_wait_completion(bau_desc, mmr_offset, right_shift, bcp, try);
else
- return uv2_wait_completion(bau_desc, mmr_offset, right_shift,
- bcp, try);
+ return uv2_3_wait_completion(bau_desc, mmr_offset, right_shift, bcp, try);
}

/*
@@ -888,7 +883,7 @@ int uv_flush_send_and_wait(struct cpumask *flush_mask, struct bau_control *bcp,
struct ptc_stats *stat = bcp->statp;
struct bau_control *hmaster = bcp->uvhub_master;
struct uv1_bau_msg_header *uv1_hdr = NULL;
- struct uv2_bau_msg_header *uv2_hdr = NULL;
+ struct uv2_3_bau_msg_header *uv2_3_hdr = NULL;

if (bcp->uvhub_version == 1) {
uv1 = 1;
@@ -902,27 +897,28 @@ int uv_flush_send_and_wait(struct cpumask *flush_mask, struct bau_control *bcp,
if (uv1)
uv1_hdr = &bau_desc->header.uv1_hdr;
else
- uv2_hdr = &bau_desc->header.uv2_hdr;
+ /* uv2 and uv3 */
+ uv2_3_hdr = &bau_desc->header.uv2_3_hdr;

do {
if (try == 0) {
if (uv1)
uv1_hdr->msg_type = MSG_REGULAR;
else
- uv2_hdr->msg_type = MSG_REGULAR;
+ uv2_3_hdr->msg_type = MSG_REGULAR;
seq_number = bcp->message_number++;
} else {
if (uv1)
uv1_hdr->msg_type = MSG_RETRY;
else
- uv2_hdr->msg_type = MSG_RETRY;
+ uv2_3_hdr->msg_type = MSG_RETRY;
stat->s_retry_messages++;
}

if (uv1)
uv1_hdr->sequence = seq_number;
else
- uv2_hdr->sequence = seq_number;
+ uv2_3_hdr->sequence = seq_number;
index = (1UL << AS_PUSH_SHIFT) | bcp->uvhub_cpu;
bcp->send_message = get_cycles();

@@ -1080,8 +1076,10 @@ static int set_distrib_bits(struct cpumask *flush_mask, struct bau_control *bcp,
* done. The returned pointer is valid till preemption is re-enabled.
*/
const struct cpumask *uv_flush_tlb_others(const struct cpumask *cpumask,
- struct mm_struct *mm, unsigned long start,
- unsigned long end, unsigned int cpu)
+ struct mm_struct *mm,
+ unsigned long start,
+ unsigned long end,
+ unsigned int cpu)
{
int locals = 0;
int remotes = 0;
@@ -1268,6 +1266,7 @@ void uv_bau_message_interrupt(struct pt_regs *regs)
if (bcp->uvhub_version == 2)
process_uv2_message(&msgdesc, bcp);
else
+ /* no error workaround for uv1 or uv3 */
bau_process_message(&msgdesc, bcp, 1);

msg++;
@@ -1325,8 +1324,12 @@ static void __init enable_timeouts(void)
*/
mmr_image |= (1L << SOFTACK_MSHIFT);
if (is_uv2_hub()) {
+ /* do not touch the legacy mode bit */
/* hw bug workaround; do not use extended status */
mmr_image &= ~(1L << UV2_EXT_SHFT);
+ } else if (is_uv3_hub()) {
+ mmr_image &= ~(1L << PREFETCH_HINT_SHFT);
+ mmr_image |= (1L << SB_STATUS_SHFT);
}
write_mmr_misc_control(pnode, mmr_image);
}
@@ -1692,7 +1695,7 @@ static void activation_descriptor_init(int node, int pnode, int base_pnode)
struct bau_desc *bau_desc;
struct bau_desc *bd2;
struct uv1_bau_msg_header *uv1_hdr;
- struct uv2_bau_msg_header *uv2_hdr;
+ struct uv2_3_bau_msg_header *uv2_3_hdr;
struct bau_control *bcp;

/*
@@ -1739,15 +1742,15 @@ static void activation_descriptor_init(int node, int pnode, int base_pnode)
*/
} else {
/*
- * BIOS uses legacy mode, but UV2 hardware always
+ * BIOS uses legacy mode, but uv2 and uv3 hardware always
* uses native mode for selective broadcasts.
*/
- uv2_hdr = &bd2->header.uv2_hdr;
- uv2_hdr->swack_flag = 1;
- uv2_hdr->base_dest_nasid =
+ uv2_3_hdr = &bd2->header.uv2_3_hdr;
+ uv2_3_hdr->swack_flag = 1;
+ uv2_3_hdr->base_dest_nasid =
UV_PNODE_TO_NASID(base_pnode);
- uv2_hdr->dest_subnodeid = UV_LB_SUBNODEID;
- uv2_hdr->command = UV_NET_ENDPOINT_INTD;
+ uv2_3_hdr->dest_subnodeid = UV_LB_SUBNODEID;
+ uv2_3_hdr->command = UV_NET_ENDPOINT_INTD;
}
}
for_each_present_cpu(cpu) {
@@ -1858,6 +1861,7 @@ static int calculate_destination_timeout(void)
ts_ns *= (mult1 * mult2);
ret = ts_ns / 1000;
} else {
+ /* same destination timeout for uv2 and uv3 */
/* 4 bits 0/1 for 10/80us base, 3 bits of multiplier */
mmr_image = uv_read_local_mmr(UVH_LB_BAU_MISC_CONTROL);
mmr_image = (mmr_image & UV_SA_MASK) >> UV_SA_SHFT;
@@ -2012,8 +2016,10 @@ static int scan_sock(struct socket_desc *sdp, struct uvhub_desc *bdp,
bcp->uvhub_version = 1;
else if (is_uv2_hub())
bcp->uvhub_version = 2;
+ else if (is_uv3_hub())
+ bcp->uvhub_version = 3;
else {
- printk(KERN_EMERG "uvhub version not 1 or 2\n");
+ printk(KERN_EMERG "uvhub version not 1, 2 or 3\n");
return 1;
}
bcp->uvhub_master = *hmasterp;
@@ -2138,9 +2144,10 @@ static int __init uv_bau_init(void)
}

vector = UV_BAU_MESSAGE;
- for_each_possible_blade(uvhub)
+ for_each_possible_blade(uvhub) {
if (uv_blade_nr_possible_cpus(uvhub))
init_uvhub(uvhub, vector, uv_base_pnode);
+ }

alloc_intr_gate(vector, uv_bau_message_intr1);

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/