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author | Rickard Green <rickard@erlang.org> | 2010-10-10 20:23:13 +0200 |
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committer | Rickard Green <rickard@erlang.org> | 2010-11-18 14:36:24 +0100 |
commit | b328ed0ffc52bcb8936365c97e28f91954692989 (patch) | |
tree | 537360ea873ea32609a1fff29d86293d4bc54780 /erts | |
parent | 17224a3d31d25ce6daa4de63b52b26bee9564bcd (diff) | |
download | otp-b328ed0ffc52bcb8936365c97e28f91954692989.tar.gz otp-b328ed0ffc52bcb8936365c97e28f91954692989.tar.bz2 otp-b328ed0ffc52bcb8936365c97e28f91954692989.zip |
Thread specific inet driver buffer stack
The inet driver internal buffer stack implementation
has been rewritten in order to reduce lock contention.
Diffstat (limited to 'erts')
-rw-r--r-- | erts/emulator/drivers/common/inet_drv.c | 151 |
1 files changed, 53 insertions, 98 deletions
diff --git a/erts/emulator/drivers/common/inet_drv.c b/erts/emulator/drivers/common/inet_drv.c index 3de48194fb..c02a82372e 100644 --- a/erts/emulator/drivers/common/inet_drv.c +++ b/erts/emulator/drivers/common/inet_drv.c @@ -1251,88 +1251,62 @@ static int load_ip_and_port LOAD_ATOM((spec), (i), (flag) ? am_true : am_false); #endif /* HAVE_SCTP */ +/* Assume a cache line size of 64 bytes */ +#define INET_DRV_CACHE_LINE_SIZE ((ErlDrvUInt) 64) +#define INET_DRV_CACHE_LINE_MASK (INET_DRV_CACHE_LINE_SIZE - 1) + /* ** Binary Buffer Managment ** We keep a stack of usable buffers */ -#define BUFFER_STACK_SIZE 16 - -static erts_smp_spinlock_t inet_buffer_stack_lock; -static ErlDrvBinary* buffer_stack[BUFFER_STACK_SIZE]; -static int buffer_stack_pos = 0; - +#define BUFFER_STACK_SIZE 15 -/* - * XXX - * The erts_smp_spin_* functions should not be used by drivers (but this - * driver is special). Replace when driver locking api has been implemented. - * /rickard - */ -#define BUFSTK_LOCK erts_smp_spin_lock(&inet_buffer_stack_lock); -#define BUFSTK_UNLOCK erts_smp_spin_unlock(&inet_buffer_stack_lock); - -#ifdef DEBUG -static int tot_buf_allocated = 0; /* memory in use for i_buf */ -static int tot_buf_stacked = 0; /* memory on stack */ -static int max_buf_allocated = 0; /* max allocated */ - -#define COUNT_BUF_ALLOC(sz) do { \ - BUFSTK_LOCK; \ - tot_buf_allocated += (sz); \ - if (tot_buf_allocated > max_buf_allocated) \ - max_buf_allocated = tot_buf_allocated; \ - BUFSTK_UNLOCK; \ -} while(0) - -#define COUNT_BUF_FREE(sz) do { \ - BUFSTK_LOCK; \ - tot_buf_allocated -= (sz); \ - BUFSTK_UNLOCK; \ - } while(0) - -#define COUNT_BUF_STACK(sz) do { \ - BUFSTK_LOCK; \ - tot_buf_stacked += (sz); \ - BUFSTK_UNLOCK; \ - } while(0) - -#else +ErlDrvTSDKey buffer_stack_key; -#define COUNT_BUF_ALLOC(sz) -#define COUNT_BUF_FREE(sz) -#define COUNT_BUF_STACK(sz) +typedef struct { + int pos; + ErlDrvBinary* stk[BUFFER_STACK_SIZE]; +} InetDrvBufStkBase; -#endif +typedef struct { + InetDrvBufStkBase buf; + char align[(((sizeof(InetDrvBufStkBase) - 1) / INET_DRV_CACHE_LINE_SIZE) + 1) + * INET_DRV_CACHE_LINE_SIZE]; +} InetDrvBufStk; + +static InetDrvBufStk *get_bufstk(void) +{ + InetDrvBufStk *bs = erl_drv_tsd_get(buffer_stack_key); + if (bs) + return bs; + bs = driver_alloc(sizeof(InetDrvBufStk) + + INET_DRV_CACHE_LINE_SIZE - 1); + if (!bs) + return NULL; + if ((((ErlDrvUInt) bs) & INET_DRV_CACHE_LINE_MASK) != 0) + bs = ((InetDrvBufStk *) + ((((ErlDrvUInt) bs) & ~INET_DRV_CACHE_LINE_MASK) + + INET_DRV_CACHE_LINE_SIZE)); + erl_drv_tsd_set(buffer_stack_key, bs); + bs->buf.pos = 0; + return bs; +} static ErlDrvBinary* alloc_buffer(long minsz) { - ErlDrvBinary* buf = NULL; + InetDrvBufStk *bs = get_bufstk(); - BUFSTK_LOCK; + DEBUGF(("alloc_buffer: %ld\r\n", minsz)); - DEBUGF(("alloc_buffer: sz = %ld, tot = %d, max = %d\r\n", - minsz, tot_buf_allocated, max_buf_allocated)); + if (bs && bs->buf.pos > 0) { + ErlDrvBinary* buf = bs->buf.stk[--bs->buf.pos]; + if (buf->orig_size >= minsz) + return buf; - if (buffer_stack_pos > 0) { - int origsz; - - buf = buffer_stack[--buffer_stack_pos]; - origsz = buf->orig_size; - BUFSTK_UNLOCK; - COUNT_BUF_STACK(-origsz); - if (origsz < minsz) { - if ((buf = driver_realloc_binary(buf, minsz)) == NULL) - return NULL; - COUNT_BUF_ALLOC(buf->orig_size - origsz); - } - } - else { - BUFSTK_UNLOCK; - if ((buf = driver_alloc_binary(minsz)) == NULL) - return NULL; - COUNT_BUF_ALLOC(buf->orig_size); + driver_free_binary(buf); } - return buf; + + return driver_alloc_binary(minsz); } /* @@ -1342,14 +1316,14 @@ static ErlDrvBinary* alloc_buffer(long minsz) /*#define CHECK_DOUBLE_RELEASE 1*/ static void release_buffer(ErlDrvBinary* buf) { + InetDrvBufStk *bs; DEBUGF(("release_buffer: %ld\r\n", (buf==NULL) ? 0 : buf->orig_size)); - if (buf == NULL) + if (!buf) return; - BUFSTK_LOCK; - if ((buf->orig_size > INET_MAX_BUFFER) || - (buffer_stack_pos >= BUFFER_STACK_SIZE)) { - BUFSTK_UNLOCK; - COUNT_BUF_FREE(buf->orig_size); + bs = get_bufstk(); + if ((buf->orig_size > INET_MAX_BUFFER) + || !bs + || (bs->buf.pos >= BUFFER_STACK_SIZE)) { driver_free_binary(buf); } else { @@ -1366,24 +1340,13 @@ static void release_buffer(ErlDrvBinary* buf) } } #endif - buffer_stack[buffer_stack_pos++] = buf; - BUFSTK_UNLOCK; - COUNT_BUF_STACK(buf->orig_size); + bs->buf.stk[bs->buf.pos++] = buf; } } static ErlDrvBinary* realloc_buffer(ErlDrvBinary* buf, long newsz) { - ErlDrvBinary* bin; -#ifdef DEBUG - long orig_size = buf->orig_size; -#endif - - if ((bin = driver_realloc_binary(buf,newsz)) != NULL) { - COUNT_BUF_ALLOC(newsz - orig_size); - ; - } - return bin; + return driver_realloc_binary(buf, newsz); } /* use a TRICK, access the refc field to see if any one else has @@ -1397,10 +1360,8 @@ static void free_buffer(ErlDrvBinary* buf) if (buf != NULL) { if (driver_binary_get_refc(buf) == 1) release_buffer(buf); - else { - COUNT_BUF_FREE(buf->orig_size); + else driver_free_binary(buf); - } } } @@ -3404,20 +3365,14 @@ static int inet_init() if (!sock_init()) goto error; - buffer_stack_pos = 0; - - erts_smp_spinlock_init(&inet_buffer_stack_lock, "inet_buffer_stack_lock"); + if (0 != erl_drv_tsd_key_create("inet_buffer_stack_key", &buffer_stack_key)) + goto error; ASSERT(sizeof(struct in_addr) == 4); # if defined(HAVE_IN6) && defined(AF_INET6) ASSERT(sizeof(struct in6_addr) == 16); # endif -#ifdef DEBUG - tot_buf_allocated = 0; - max_buf_allocated = 0; - tot_buf_stacked = 0; -#endif INIT_ATOM(ok); INIT_ATOM(tcp); INIT_ATOM(udp); |