Oren Laadan wrote: > diff --git a/checkpoint/sys.c b/checkpoint/sys.c > index 375129c..bd14ef9 100644 > --- a/checkpoint/sys.c > +++ b/checkpoint/sys.c > +/* > + * During checkpoint and restart the code writes outs/reads in data > + * to/from the checkpoint image from/to a temporary buffer (ctx->hbuf). > + * Because operations can be nested, use cr_hbuf_get() to reserve space > + * in the buffer, then cr_hbuf_put() when you no longer need that space. > + */ This seems a bit over-kill for buffer management no? The only large header seems to be cr_hdr_head and the blowup comes from utsinfo string data (which could easily be moved out to be in it's own CR_HDR_STRING blocks). Wouldn't it be easier to use stack-local storage than balancing the cr_hbuf_get/put routines? > + > +/* > + * ctx->hbuf is used to hold headers and data of known (or bound), > + * static sizes. In some cases, multiple headers may be allocated in > + * a nested manner. The size should accommodate all headers, nested > + * or not, on all archs. > + */ > +#define CR_HBUF_TOTAL (8 * 4096) > + > +/** > + * cr_hbuf_get - reserve space on the hbuf > + * @ctx: checkpoint context > + * @n: number of bytes to reserve > + * > + * Returns pointer to reserved space > + */ > +void *cr_hbuf_get(struct cr_ctx *ctx, int n) > +{ > + void *ptr; > + > + /* > + * Since requests depend on logic and static header sizes (not on > + * user data), space should always suffice, unless someone either > + * made a structure bigger or call path deeper than expected. > + */ > + BUG_ON(ctx->hpos + n > CR_HBUF_TOTAL); > + ptr = ctx->hbuf + ctx->hpos; > + ctx->hpos += n; > + return ptr; > +} > + > +/** > + * cr_hbuf_put - unreserve space on the hbuf > + * @ctx: checkpoint context > + * @n: number of bytes to reserve > + */ > +void cr_hbuf_put(struct cr_ctx *ctx, int n) > +{ > + BUG_ON(ctx->hpos < n); > + ctx->hpos -= n; > +} > + _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers