: Allocation in atomic context and simplify interface
PATCH v2 1/8 : Allocation in atomic context and simplify interface
[CCID2]: Allocation in atomic context and simplify interface
1.) This fixes the following bug reported in syslog:
[ 4039.051658] BUG: sleeping function called from invalid context at /usr/src/davem-2.6/mm/slab.c:3032 [ 4039.051668] in_atomic():1, irqs_disabled():0 [ 4039.051670] INFO: lockdep is turned off. [ 4039.051674] [<c0104c0f>] show_trace_log_lvl+0x1a/0x30 [ 4039.051687] [<c0104d4d>] show_trace+0x12/0x14 [ 4039.051691] [<c0104d65>] dump_stack+0x16/0x18 [ 4039.051695] [<c011371e>] __might_sleep+0xaf/0xbe [ 4039.051700] [<c0157b66>] __kmalloc+0xb1/0xd0 [ 4039.051706] [<f090416f>] ccid2_hc_tx_alloc_seq+0x35/0xc3 [dccp_ccid2] [ 4039.051717] [<f09048d6>] ccid2_hc_tx_packet_sent+0x27f/0x2d9 [dccp_ccid2] [ 4039.051723] [<f085486b>] dccp_write_xmit+0x1eb/0x338 [dccp] [ 4039.051741] [<f085603d>] dccp_sendmsg+0x113/0x18f [dccp] [ 4039.051750] [<c03907fc>] inet_sendmsg+0x2e/0x4c [ 4039.051758] [<c033a47d>] sock_aio_write+0xd5/0x107 [ 4039.051766] [<c015abc1>] do_sync_write+0xcd/0x11c [ 4039.051772] [<c015b296>] vfs_write+0x118/0x11f [ 4039.051840] [<c015b932>] sys_write+0x3d/0x64 [ 4039.051845] [<c0103e7c>] syscall_call+0x7/0xb [ 4039.051848] ===========
The problem was that GFP_KERNEL was used; fixed by using gfp_any().
2.) While at it, the interface of ccid2_hc_tx_alloc_seq() has been simplified:
* ccid2_hc_tx_alloc_seq() is always called with an argument of CCID2_SEQBUF_LEN;
* other code - ccid2_hc_tx_check_sanity() - even depends on the assumption that
ccid2_hc_tx_alloc_seq() has been called with this particular size;
* passing the `gfp_t' argument to ccid2_hc_tx_alloc_seq() is redundant with gfp_any().
Signed-off-by Gerrit Renker <[email protected]>
--- net/dccp/ccids/ccid2.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-)
net/dccp/ccids/ccid2.c +9 -10
@@ -83,8 +83,7 @@ static void ccid2_hc_tx_check_sanity(con#define ccid2_hc_tx_check_sanity (hctx)#endif -static int ccid2_hc_tx_alloc_seq (struct ccid2_hc_tx_sock *hctx,int num, -gfp_t gfp) +static int ccid2_hc_tx_alloc_seq (struct ccid2_hc_tx_sock *hctx) {struct ccid2_seq *seqp;int i;
@@ -95,16 +94,16 @@ static int ccid2_hc_tx_alloc_seq(structreturn -ENOMEM ;/* allocate buffer and initialize linked list */ - seqp =kmalloc (sizeof (*seqp) * num, gfp); + seqp =kmalloc (CCID2_SEQBUF_LEN *sizeof (struct ccid2_seq ),gfp_any ());if (seqp =NULL )return -ENOMEM ; -for (i =0 ; i < (num -1 ); i++) { +for (i =0 ; i < (CCID2_SEQBUF_LEN -1 ); i++) { seqp[i].ccid2s_next = &seqp[i +1 ]; seqp[i +1 ].ccid2s_prev = &seqp[i]; } - seqp[num -1 ].ccid2s_next = seqp; - seqp->ccid2s_prev = &seqp[num -1 ]; + seqp[CCID2_SEQBUF_LEN -1 ].ccid2s_next = seqp; + seqp->ccid2s_prev = &seqp[CCID2_SEQBUF_LEN -1 ];/* This is the first allocation. Initiate the head and tail. */ if (hctx->ccid2hctx_seqbufc =0 )
@@ -114,8 +113,8 @@ static int ccid2_hc_tx_alloc_seq(struct hctx->ccid2hctx_seqh->ccid2s_next = seqp; seqp->ccid2s_prev = hctx->ccid2hctx_seqh; - hctx->ccid2hctx_seqt->ccid2s_prev = &seqp[num -1 ]; - seqp[num -1 ].ccid2s_next = hctx->ccid2hctx_seqt; + hctx->ccid2hctx_seqt->ccid2s_prev = &seqp[CCID2_SEQBUF_LEN -1 ]; + seqp[CCID2_SEQBUF_LEN -1 ].ccid2s_next = hctx->ccid2hctx_seqt; }/* store the original pointer to the buffer so we can free it */
@@ -298,7 +297,7 @@ static void ccid2_hc_tx_packet_sent(struint rc;ccid2_pr_debug ("allocating more space in history\n" ); - rc =ccid2_hc_tx_alloc_seq (hctx,CCID2_SEQBUF_LEN ,GFP_KERNEL ); + rc =ccid2_hc_tx_alloc_seq (hctx);BUG_ON (rc);/* XXX what do we do? */ next = hctx->ccid2hctx_seqh->ccid2s_next;
@@ -771,7 +770,7 @@ static int ccid2_hc_tx_init(struct ccid hctx->ccid2hctx_seqbufc =0 ;/* XXX init ~ to window size... */ -if (ccid2_hc_tx_alloc_seq (hctx,CCID2_SEQBUF_LEN ,GFP_ATOMIC ) !=0 ) +if (ccid2_hc_tx_alloc_seq (hctx))return -ENOMEM ; hctx->ccid2hctx_sent =0 ;