On 11/12/17(Mon) 08:55, Martin Pieuchot wrote: > Diff below shuffle the socket buffer definition to "properly" memset() > all required fields in sorflush(). It also gets rid of the sbrelease() > abstraction since zeroing out `sb_hiwat' and `sb_mbmax' is required in > only one place.
Simpler diff that just do the zeroing, anyone? Index: kern/uipc_socket.c =================================================================== RCS file: /cvs/src/sys/kern/uipc_socket.c,v retrieving revision 1.212 diff -u -p -r1.212 uipc_socket.c --- kern/uipc_socket.c 19 Dec 2017 09:29:37 -0000 1.212 +++ kern/uipc_socket.c 27 Dec 2017 15:08:58 -0000 @@ -1052,12 +1052,8 @@ sorflush(struct socket *so) sbunlock(so, sb); aso.so_proto = pr; aso.so_rcv = *sb; - memset(sb, 0, sizeof (*sb)); - /* XXX - the memset stomps all over so_rcv */ - if (aso.so_rcv.sb_flagsintr & SB_KNOTE) { - sb->sb_sel.si_note = aso.so_rcv.sb_sel.si_note; - sb->sb_flagsintr = SB_KNOTE; - } + memset(&sb->sb_startzero, 0, + (caddr_t)&sb->sb_endzero - (caddr_t)&sb->sb_startzero); if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose) (*pr->pr_domain->dom_dispose)(aso.so_rcv.sb_mb); sbrelease(&aso, &aso.so_rcv); Index: sys/socketvar.h =================================================================== RCS file: /cvs/src/sys/sys/socketvar.h,v retrieving revision 1.80 diff -u -p -r1.80 socketvar.h --- sys/socketvar.h 18 Dec 2017 10:07:55 -0000 1.80 +++ sys/socketvar.h 27 Dec 2017 15:07:10 -0000 @@ -98,6 +98,8 @@ struct socket { * Variables for socket buffering. */ struct sockbuf { +/* The following fields are all zeroed on flush. */ +#define sb_startzero sb_cc u_long sb_cc; /* actual chars in buffer */ u_long sb_datacc; /* data only chars in buffer */ u_long sb_hiwat; /* max actual char count */ @@ -109,10 +111,12 @@ struct socket { struct mbuf *sb_mbtail; /* the last mbuf in the chain */ struct mbuf *sb_lastrecord;/* first mbuf of last record in socket buffer */ - struct selinfo sb_sel; /* process selecting read/write */ - int sb_flagsintr; /* flags, changed during interrupt */ - short sb_flags; /* flags, see below */ u_short sb_timeo; /* timeout for read/write */ + short sb_flags; /* flags, see below */ +/* End area that is zeroed on flush. */ +#define sb_endzero sb_flags + int sb_flagsintr; /* flags, changed atomically */ + struct selinfo sb_sel; /* process selecting read/write */ } so_rcv, so_snd; #define SB_MAX (2*1024*1024) /* default for max chars in sockbuf */ #define SB_LOCK 0x01 /* lock on data queue */