On Wed, 2005-12-14 at 11:17 +0000, Alan Cox wrote: > On Mer, 2005-12-14 at 01:12 -0800, Sridhar Samudrala wrote: > > Pass __GFP_CRITICAL flag with all allocation requests that are critical. > > - All allocations needed to process incoming packets are marked as CRITICAL. > > This includes the allocations > > - made by the driver to receive incoming packets > > - to process and send ARP packets > > - to create new routes for incoming packets > > But your user space that would add the routes is not so protected so I'm > not sure this is actually a solution, more of an extended fudge. In > which case I'm not clear why it is any better than the current > GFP_ATOMIC approach.
I am not referring to routes that are added by user-space, but the allocations needed for cached routes stored in skb->dst in ip_route_input() path. > > +#define SK_CRIT_ALLOC(sk, flags) ((sk->sk_allocation & __GFP_CRITICAL) | > > flags) > > Lots of hidden conditional logic on critical paths. Also sk should be in > brackets so that the macro evaluation order is defined as should flags > > > +#define CRIT_ALLOC(flags) (__GFP_CRITICAL | flags) > > Pointless obfuscation The only reason i made these macros is that i would expect this to a compile time configurable option so that there is zero overhead for regular users. #ifdef CONFIG_CRIT_SOCKET #define SK_CRIT_ALLOC(sk, flags) ((sk->sk_allocation & __GFP_CRITICAL) | flags) #define CRIT_ALLOC(flags) (__GFP_CRITICAL | flags) #else #define SK_CRIT_ALLOC(sk, flags) flags #define CRIT_ALLOC(flags) flags #endif Thanks Sridhar - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
