diff options
| author | Anup Patel <anup.patel@wdc.com> | 2019-04-03 10:24:03 +0530 |
|---|---|---|
| committer | Atish Patra <atishp04@gmail.com> | 2019-04-03 13:48:38 -0700 |
| commit | 9dc95021dbf29b96a84e0b7dca491f768aa0ef0d (patch) | |
| tree | ec694df5cafb17c992f3107336cbddc33dff7815 | |
| parent | 6dc1b0f6e2f895f220c284d9166205400fc98428 (diff) | |
lib: More improvements to sbi_fifo
This patch does following improvements to sbi_fifo:
1. Use valid SBI_Exxxx error codes instead of -1
2. The sbi_fifo_is_full() and sbi_fifo_is_empty() did
not acquire qlock before accessing head and tail
hence fixed it
3. Added avail member for ease in debugging and simplifying
head/tail updates.
Due to above changes size of sbi_fifo changes from 48 bytes
to 56 bytes.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
| -rw-r--r-- | include/sbi/sbi_error.h | 1 | ||||
| -rw-r--r-- | include/sbi/sbi_fifo.h | 18 | ||||
| -rw-r--r-- | lib/sbi_fifo.c | 93 | ||||
| -rw-r--r-- | lib/sbi_ipi.c | 4 |
4 files changed, 73 insertions, 43 deletions
diff --git a/include/sbi/sbi_error.h b/include/sbi/sbi_error.h index 68076e7..300ee74 100644 --- a/include/sbi/sbi_error.h +++ b/include/sbi/sbi_error.h @@ -21,5 +21,6 @@ #define SBI_ETIMEDOUT -8 #define SBI_EIO -9 #define SBI_EILL -10 +#define SBI_ENOSPC -11 #endif diff --git a/include/sbi/sbi_fifo.h b/include/sbi/sbi_fifo.h index ba9769b..1a59518 100644 --- a/include/sbi/sbi_fifo.h +++ b/include/sbi/sbi_fifo.h @@ -15,18 +15,22 @@ #include <sbi/sbi_types.h> struct sbi_fifo { - int head; - int tail; - spinlock_t qlock; - unsigned long entrysize; - unsigned long num_entries; + /* Static members of struct */ void *queue; + unsigned long entry_size; + unsigned long num_entries; + /* Dynamic members of struct protected by lock */ + spinlock_t qlock; + unsigned long avail; + unsigned long head; + unsigned long tail; }; int sbi_fifo_dequeue(struct sbi_fifo *fifo, void *data); int sbi_fifo_enqueue(struct sbi_fifo *fifo, void *data); -void sbi_fifo_init(struct sbi_fifo *fifo, unsigned long entries, - unsigned long entrysize); +void sbi_fifo_init(struct sbi_fifo *fifo, void *queue_mem, + unsigned long entries, unsigned long entry_size); bool sbi_fifo_is_empty(struct sbi_fifo *fifo); bool sbi_fifo_is_full(struct sbi_fifo *fifo); + #endif diff --git a/lib/sbi_fifo.c b/lib/sbi_fifo.c index 1b283e8..c0010e4 100644 --- a/lib/sbi_fifo.c +++ b/lib/sbi_fifo.c @@ -8,51 +8,75 @@ * */ #include <sbi/riscv_locks.h> +#include <sbi/sbi_error.h> #include <sbi/sbi_fifo.h> #include <plat/string.h> -void sbi_fifo_init(struct sbi_fifo *fifo, unsigned long entries, - unsigned long size) +void sbi_fifo_init(struct sbi_fifo *fifo, void *queue_mem, + unsigned long entries, unsigned long entry_size) { - fifo->head = -1; - fifo->tail = -1; + fifo->queue = queue_mem; fifo->num_entries = entries; - fifo->entrysize = size; + fifo->entry_size = entry_size; SPIN_LOCK_INIT(&fifo->qlock); - memset(fifo->queue, 0, entries * size); + fifo->avail = fifo->head = fifo->tail = 0; + memset(fifo->queue, 0, entries * entry_size); +} + +/* Note: must be called with fifo->qlock held */ +static inline bool __sbi_fifo_is_full(struct sbi_fifo *fifo) +{ + return (fifo->avail == fifo->num_entries) ? TRUE : FALSE; } bool sbi_fifo_is_full(struct sbi_fifo *fifo) { - if (((fifo->head == fifo->num_entries-1) && fifo->tail == 0) || - (fifo->tail == fifo->head + 1)) { - return TRUE; - } - return FALSE; + bool ret; + + spin_lock(&fifo->qlock); + ret = __sbi_fifo_is_full(fifo); + spin_unlock(&fifo->qlock); + + return ret; +} + +/* Note: must be called with fifo->qlock held */ +static inline bool __sbi_fifo_is_empty(struct sbi_fifo *fifo) +{ + return (fifo->avail == 0) ? TRUE : FALSE; } bool sbi_fifo_is_empty(struct sbi_fifo *fifo) { - if (fifo->head == -1) - return TRUE; - return FALSE; + bool ret; + + spin_lock(&fifo->qlock); + ret = __sbi_fifo_is_empty(fifo); + spin_unlock(&fifo->qlock); + + return ret; } int sbi_fifo_enqueue(struct sbi_fifo *fifo, void *data) { if (!fifo || !data) - return -1; + return SBI_EINVAL; spin_lock(&fifo->qlock); - if (sbi_fifo_is_full(fifo)) { + + if (__sbi_fifo_is_full(fifo)) { spin_unlock(&fifo->qlock); - return -1; + return SBI_ENOSPC; } - if (fifo->tail == -1) - fifo->tail = 0; - fifo->head = (fifo->head + 1) % fifo->num_entries; - memcpy(fifo->queue + fifo->head * fifo->entrysize, data, - fifo->entrysize); + + memcpy(fifo->queue + fifo->head * fifo->entry_size, data, + fifo->entry_size); + + fifo->avail++; + fifo->head++; + if (fifo->head >= fifo->num_entries) + fifo->head = 0; + spin_unlock(&fifo->qlock); return 0; @@ -61,22 +85,23 @@ int sbi_fifo_enqueue(struct sbi_fifo *fifo, void *data) int sbi_fifo_dequeue(struct sbi_fifo *fifo, void *data) { if (!fifo || !data) - return -1; + return SBI_EINVAL; spin_lock(&fifo->qlock); - if (sbi_fifo_is_empty(fifo)) { + + if (__sbi_fifo_is_empty(fifo)) { spin_unlock(&fifo->qlock); - return -1; - } - memcpy(data, fifo->queue + fifo->tail * fifo->entrysize, - fifo->entrysize); - - if (fifo->tail == fifo->head) { - fifo->tail = -1; - fifo->head = -1; - } else { - fifo->tail = (fifo->tail + 1) % fifo->num_entries; + return SBI_ENOENT; } + + memcpy(data, fifo->queue + fifo->tail * fifo->entry_size, + fifo->entry_size); + + fifo->avail--; + fifo->tail++; + if (fifo->tail >= fifo->num_entries) + fifo->tail = 0; + spin_unlock(&fifo->qlock); return 0; diff --git a/lib/sbi_ipi.c b/lib/sbi_ipi.c index 4253fb1..cc61dbd 100644 --- a/lib/sbi_ipi.c +++ b/lib/sbi_ipi.c @@ -184,8 +184,8 @@ int sbi_ipi_init(struct sbi_scratch *scratch, bool cold_boot) struct sbi_fifo *tlb_info_q = sbi_tlb_fifo_head_ptr(scratch); sbi_ipi_data_ptr(scratch)->ipi_type = 0x00; - tlb_info_q->queue = sbi_tlb_fifo_mem_ptr(scratch); - sbi_fifo_init(tlb_info_q, SBI_TLB_FIFO_NUM_ENTRIES, SBI_TLB_INFO_SIZE); + sbi_fifo_init(tlb_info_q, sbi_tlb_fifo_mem_ptr(scratch), + SBI_TLB_FIFO_NUM_ENTRIES, SBI_TLB_INFO_SIZE); /* Enable software interrupts */ csr_set(CSR_MIE, MIP_MSIP); |