On 09/29/2015 06:56 PM, Dario Faggioli wrote:
The .alloc_pdata hook of the scheduler interface is called, in schedule_cpu_switch(), unconditionally, for all schedulers.This forces even schedulers that do not require any actual allocation of per-pCPU data to: - contain an implementation of the hook; - return some artificial non-NULL value to make such a caller happy. This changes allows schedulers that do not need per-pCPU allocations to avoid implementing the hook. It also kills such artificial implementation from the ARINC653 scheduler (and, while there, it nukes .free_pdata from there too, which is equally useless). Signed-off-by: Dario Faggioli <dario.faggi...@citrix.com> --- Cc: George Dunlap <george.dun...@eu.citrix.com> Cc: Robert VanVossen <robert.vanvos...@dornerworks.com> Cc: Josh Whitehead <josh.whiteh...@dornerworks.com> --- xen/common/sched_arinc653.c | 31 ------------------------------- xen/common/schedule.c | 6 +++--- 2 files changed, 3 insertions(+), 34 deletions(-) diff --git a/xen/common/sched_arinc653.c b/xen/common/sched_arinc653.c index cff5da9..ef192c3 100644 --- a/xen/common/sched_arinc653.c +++ b/xen/common/sched_arinc653.c @@ -455,34 +455,6 @@ a653sched_free_vdata(const struct scheduler *ops, void *priv) } /** - * This function allocates scheduler-specific data for a physical CPU - * - * We do not actually make use of any per-CPU data but the hypervisor expects - * a non-NULL return value - * - * @param ops Pointer to this instance of the scheduler structure - * - * @return Pointer to the allocated data - */ -static void * -a653sched_alloc_pdata(const struct scheduler *ops, int cpu) -{ - /* return a non-NULL value to keep schedule.c happy */ - return SCHED_PRIV(ops); -} - -/** - * This function frees scheduler-specific data for a physical CPU - * - * @param ops Pointer to this instance of the scheduler structure - */ -static void -a653sched_free_pdata(const struct scheduler *ops, void *pcpu, int cpu) -{ - /* nop */ -} - -/** * This function allocates scheduler-specific data for a domain * * We do not actually make use of any per-domain data but the hypervisor @@ -736,9 +708,6 @@ const struct scheduler sched_arinc653_def = { .free_vdata = a653sched_free_vdata, .alloc_vdata = a653sched_alloc_vdata, - .free_pdata = a653sched_free_pdata, - .alloc_pdata = a653sched_alloc_pdata, - .free_domdata = a653sched_free_domdata, .alloc_domdata = a653sched_alloc_domdata, diff --git a/xen/common/schedule.c b/xen/common/schedule.c index 83244d7..0e02af2 100644 --- a/xen/common/schedule.c +++ b/xen/common/schedule.c @@ -1493,7 +1493,7 @@ void __init scheduler_init(void) int schedule_cpu_switch(unsigned int cpu, struct cpupool *c) { struct vcpu *idle; - void *ppriv, *ppriv_old, *vpriv, *vpriv_old; + void *ppriv = NULL, *ppriv_old, *vpriv, *vpriv_old; struct scheduler *old_ops = per_cpu(scheduler, cpu); struct scheduler *new_ops = (c == NULL) ? &ops : c->sched; @@ -1501,8 +1501,8 @@ int schedule_cpu_switch(unsigned int cpu, struct cpupool *c) return 0; idle = idle_vcpu[cpu]; - ppriv = SCHED_OP(new_ops, alloc_pdata, cpu); - if ( ppriv == NULL ) + if ( (new_ops->alloc_pdata != NULL) && + ((ppriv = new_ops->alloc_pdata(new_ops, cpu)) == NULL) ) return -ENOMEM; vpriv = SCHED_OP(new_ops, alloc_vdata, idle, idle->domain->sched_priv); if ( vpriv == NULL )
Just below this there are 2 SCHED_OP calls to free_pdata. You'll have to check whether the hook is present as you just have nuked it above. Juergen _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
