lib: sbi: Optimize sbi_tlb queue waiting

When tlb_fifo is full, it will wait and affect the ipi update to
other harts. This patch is optimized.

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Tested-by: Anup Patel <anup@brainfault.org>
This commit is contained in:
Xiang W 2023-04-14 09:32:47 +08:00 committed by Anup Patel
parent 80078ab088
commit bf40e07f6f
3 changed files with 36 additions and 27 deletions

View file

@ -30,6 +30,12 @@ struct sbi_ipi_device {
void (*ipi_clear)(u32 target_hart);
};
enum sbi_ipi_update_type {
SBI_IPI_UPDATE_SUCCESS,
SBI_IPI_UPDATE_BREAK,
SBI_IPI_UPDATE_RETRY,
};
struct sbi_scratch;
/** IPI event operations or callbacks */
@ -41,6 +47,10 @@ struct sbi_ipi_event_ops {
* Update callback to save/enqueue data for remote HART
* Note: This is an optional callback and it is called just before
* triggering IPI to remote HART.
* @return < 0, error or failure
* @return SBI_IPI_UPDATE_SUCCESS, success
* @return SBI_IPI_UPDATE_BREAK, break IPI, done on local hart
* @return SBI_IPI_UPDATE_RETRY, need retry
*/
int (* update)(struct sbi_scratch *scratch,
struct sbi_scratch *remote_scratch,

View file

@ -53,7 +53,7 @@ static int sbi_ipi_send(struct sbi_scratch *scratch, u32 remote_hartid,
if (ipi_ops->update) {
ret = ipi_ops->update(scratch, remote_scratch,
remote_hartid, data);
if (ret < 0)
if (ret != SBI_IPI_UPDATE_SUCCESS)
return ret;
}
@ -95,51 +95,49 @@ static int sbi_ipi_sync(struct sbi_scratch *scratch, u32 event)
int sbi_ipi_send_many(ulong hmask, ulong hbase, u32 event, void *data)
{
int rc;
ulong i, m, n;
bool retry_needed;
ulong i, m;
struct sbi_hartmask target_mask = {0};
struct sbi_domain *dom = sbi_domain_thishart_ptr();
struct sbi_scratch *scratch = sbi_scratch_thishart_ptr();
/* Find the target harts */
if (hbase != -1UL) {
rc = sbi_hsm_hart_interruptible_mask(dom, hbase, &m);
if (rc)
return rc;
m &= hmask;
n = m;
/* Send IPIs */
for (i = hbase; m; i++, m >>= 1) {
if (m & 1UL)
sbi_ipi_send(scratch, i, event, data);
}
/* Sync IPIs */
m = n;
for (i = hbase; m; i++, m >>= 1) {
if (m & 1UL)
sbi_ipi_sync(scratch, event);
sbi_hartmask_set_hart(i, &target_mask);
}
} else {
/* Send IPIs */
hbase = 0;
while (!sbi_hsm_hart_interruptible_mask(dom, hbase, &m)) {
for (i = hbase; m; i++, m >>= 1) {
if (m & 1UL)
sbi_ipi_send(scratch, i, event, data);
}
hbase += BITS_PER_LONG;
}
/* Sync IPIs */
hbase = 0;
while (!sbi_hsm_hart_interruptible_mask(dom, hbase, &m)) {
for (i = hbase; m; i++, m >>= 1) {
if (m & 1UL)
sbi_ipi_sync(scratch, event);
sbi_hartmask_set_hart(i, &target_mask);
}
hbase += BITS_PER_LONG;
}
}
/* Send IPIs */
do {
retry_needed = false;
sbi_hartmask_for_each_hart(i, &target_mask) {
rc = sbi_ipi_send(scratch, i, event, data);
if (rc == SBI_IPI_UPDATE_RETRY)
retry_needed = true;
else
sbi_hartmask_clear_hart(i, &target_mask);
}
} while (retry_needed);
/* Sync IPIs */
sbi_ipi_sync(scratch, event);
return 0;
}

View file

@ -357,14 +357,14 @@ static int tlb_update(struct sbi_scratch *scratch,
*/
if (remote_hartid == curr_hartid) {
tinfo->local_fn(tinfo);
return -1;
return SBI_IPI_UPDATE_BREAK;
}
tlb_fifo_r = sbi_scratch_offset_ptr(remote_scratch, tlb_fifo_off);
ret = sbi_fifo_inplace_update(tlb_fifo_r, data, tlb_update_cb);
while (ret == SBI_FIFO_UNCHANGED && sbi_fifo_enqueue(tlb_fifo_r, data) < 0) {
if (ret == SBI_FIFO_UNCHANGED && sbi_fifo_enqueue(tlb_fifo_r, data) < 0) {
/**
* For now, Busy loop until there is space in the fifo.
* There may be case where target hart is also
@ -376,12 +376,13 @@ static int tlb_update(struct sbi_scratch *scratch,
tlb_process_once(scratch);
sbi_dprintf("hart%d: hart%d tlb fifo full\n",
curr_hartid, remote_hartid);
return SBI_IPI_UPDATE_RETRY;
}
tlb_sync = sbi_scratch_offset_ptr(scratch, tlb_sync_off);
atomic_add_return(tlb_sync, 1);
return 0;
return SBI_IPI_UPDATE_SUCCESS;
}
static struct sbi_ipi_event_ops tlb_ops = {