cbc9586c13
- FPU context is stored only if conflict between 2 FPU users or while exporting context of a process to userspace while it is the active user of FPU - FPU has its owner (fpu_owner) which points to the process whose state is currently loaded in FPU - the FPU exception is only turned on when scheduling a process which is not the owner of FPU - FPU state is restored for the process that generated the FPU exception. This process runs immediately without letting scheduler to pick a new process to resolve the FPU conflict asap, to minimize the FPU thrashing and FPU exception hadler execution - faster all non-FPU-exception kernel entries as FPU state is not checked nor saved - removed MF_USED_FPU flag, only MF_FPU_INITIALIZED remains to signal that a process has used FPU in the past
103 lines
3.1 KiB
C
103 lines
3.1 KiB
C
/* The kernel call that is implemented in this file:
|
|
* m_type: SYS_SIGSEND
|
|
*
|
|
* The parameters for this kernel call are:
|
|
* m2_i1: SIG_ENDPT # process to call signal handler
|
|
* m2_p1: SIG_CTXT_PTR # pointer to sigcontext structure
|
|
* m2_i3: SIG_FLAGS # flags for S_SIGRETURN call
|
|
*
|
|
*/
|
|
|
|
#include "kernel/system.h"
|
|
#include <signal.h>
|
|
#include <string.h>
|
|
#include <sys/sigcontext.h>
|
|
|
|
#if USE_SIGSEND
|
|
|
|
/*===========================================================================*
|
|
* do_sigsend *
|
|
*===========================================================================*/
|
|
PUBLIC int do_sigsend(struct proc * caller, message * m_ptr)
|
|
{
|
|
/* Handle sys_sigsend, POSIX-style signal handling. */
|
|
|
|
struct sigmsg smsg;
|
|
register struct proc *rp;
|
|
struct sigcontext sc, *scp;
|
|
struct sigframe fr, *frp;
|
|
int proc_nr, r;
|
|
|
|
if (!isokendpt(m_ptr->SIG_ENDPT, &proc_nr)) return(EINVAL);
|
|
if (iskerneln(proc_nr)) return(EPERM);
|
|
rp = proc_addr(proc_nr);
|
|
|
|
/* Get the sigmsg structure into our address space. */
|
|
if((r=data_copy_vmcheck(caller, caller->p_endpoint,
|
|
(vir_bytes) m_ptr->SIG_CTXT_PTR, KERNEL, (vir_bytes) &smsg,
|
|
(phys_bytes) sizeof(struct sigmsg))) != OK)
|
|
return r;
|
|
|
|
/* Compute the user stack pointer where sigcontext will be stored. */
|
|
scp = (struct sigcontext *) smsg.sm_stkptr - 1;
|
|
|
|
/* Copy the registers to the sigcontext structure. */
|
|
memcpy(&sc.sc_regs, (char *) &rp->p_reg, sizeof(sigregs));
|
|
#if (_MINIX_CHIP == _CHIP_INTEL)
|
|
if(rp->p_misc_flags & MF_FPU_INITIALIZED) {
|
|
/* save the FPU context before saving it to the sig context */
|
|
if (fpu_owner == rp) {
|
|
disable_fpu_exception();
|
|
save_fpu(rp);
|
|
}
|
|
memcpy(&sc.sc_fpu_state, rp->p_fpu_state.fpu_save_area_p,
|
|
FPU_XFP_SIZE);
|
|
}
|
|
#endif
|
|
|
|
/* Finish the sigcontext initialization. */
|
|
sc.sc_mask = smsg.sm_mask;
|
|
sc.sc_flags = 0 | rp->p_misc_flags & MF_FPU_INITIALIZED;
|
|
|
|
/* Copy the sigcontext structure to the user's stack. */
|
|
if((r=data_copy_vmcheck(caller, KERNEL, (vir_bytes) &sc, m_ptr->SIG_ENDPT,
|
|
(vir_bytes) scp, (vir_bytes) sizeof(struct sigcontext))) != OK)
|
|
return r;
|
|
|
|
/* Initialize the sigframe structure. */
|
|
frp = (struct sigframe *) scp - 1;
|
|
fr.sf_scpcopy = scp;
|
|
fr.sf_retadr2= (void (*)()) rp->p_reg.pc;
|
|
fr.sf_fp = rp->p_reg.fp;
|
|
rp->p_reg.fp = (reg_t) &frp->sf_fp;
|
|
fr.sf_scp = scp;
|
|
|
|
fpu_sigcontext(rp, &fr, &sc);
|
|
|
|
fr.sf_signo = smsg.sm_signo;
|
|
fr.sf_retadr = (void (*)()) smsg.sm_sigreturn;
|
|
|
|
/* Copy the sigframe structure to the user's stack. */
|
|
if((r=data_copy_vmcheck(caller, KERNEL, (vir_bytes) &fr,
|
|
m_ptr->SIG_ENDPT, (vir_bytes) frp,
|
|
(vir_bytes) sizeof(struct sigframe))) != OK)
|
|
return r;
|
|
|
|
/* Reset user registers to execute the signal handler. */
|
|
rp->p_reg.sp = (reg_t) frp;
|
|
rp->p_reg.pc = (reg_t) smsg.sm_sighandler;
|
|
|
|
/* Signal handler should get clean FPU. */
|
|
rp->p_misc_flags &= ~MF_FPU_INITIALIZED;
|
|
|
|
if(!RTS_ISSET(rp, RTS_PROC_STOP)) {
|
|
printf("system: warning: sigsend a running process\n");
|
|
printf("caller stack: ");
|
|
proc_stacktrace(caller);
|
|
}
|
|
|
|
return(OK);
|
|
}
|
|
|
|
#endif /* USE_SIGSEND */
|
|
|