The branch main has been updated by mhorne: URL: https://cgit.FreeBSD.org/src/commit/?id=93fe5909babb0ef7dbe8f5e3e93d429500503704
commit 93fe5909babb0ef7dbe8f5e3e93d429500503704 Author: Mitchell Horne <[email protected]> AuthorDate: 2023-06-14 16:33:41 +0000 Commit: Mitchell Horne <[email protected]> CommitDate: 2023-06-14 16:34:21 +0000 hwpmc: split out PMC_OP_PMCRW Split out the functional logic from the syscall handler into a helper function. This keeps it separate from the syscall control-flow logic, resulting in better readability overall. It also wins back a level of indentation. Reviewed by: jkoshy MFC after: 2 weeks Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D40294 --- sys/dev/hwpmc/hwpmc_mod.c | 229 +++++++++++++++++++++++----------------------- 1 file changed, 114 insertions(+), 115 deletions(-) diff --git a/sys/dev/hwpmc/hwpmc_mod.c b/sys/dev/hwpmc/hwpmc_mod.c index f9ea87769cae..b6e7baf1e7cd 100644 --- a/sys/dev/hwpmc/hwpmc_mod.c +++ b/sys/dev/hwpmc/hwpmc_mod.c @@ -3656,6 +3656,110 @@ pmc_do_op_pmcrelease(pmc_id_t pmcid) return (error); } +/* + * Main body of PMC_OP_PMCRW. + */ +static int +pmc_do_op_pmcrw(const struct pmc_op_pmcrw *prw, pmc_value_t *valp) +{ + struct pmc_binding pb; + struct pmc_classdep *pcd; + struct pmc *pm; + u_int cpu, ri, adjri; + int error; + + PMCDBG2(PMC,OPS,1, "rw id=%d flags=0x%x", prw->pm_pmcid, prw->pm_flags); + + /* Must have at least one flag set. */ + if ((prw->pm_flags & (PMC_F_OLDVALUE | PMC_F_NEWVALUE)) == 0) + return (EINVAL); + + /* Locate PMC descriptor. */ + error = pmc_find_pmc(prw->pm_pmcid, &pm); + if (error != 0) + return (error); + + /* Can't read a PMC that hasn't been started. */ + if (pm->pm_state != PMC_STATE_ALLOCATED && + pm->pm_state != PMC_STATE_STOPPED && + pm->pm_state != PMC_STATE_RUNNING) + return (EINVAL); + + /* Writing a new value is allowed only for 'STOPPED' PMCs. */ + if (pm->pm_state == PMC_STATE_RUNNING && + (prw->pm_flags & PMC_F_NEWVALUE) != 0) + return (EBUSY); + + if (PMC_IS_VIRTUAL_MODE(PMC_TO_MODE(pm))) { + /* + * If this PMC is attached to its owner (i.e., the process + * requesting this operation) and is running, then attempt to + * get an upto-date reading from hardware for a READ. Writes + * are only allowed when the PMC is stopped, so only update the + * saved value field. + * + * If the PMC is not running, or is not attached to its owner, + * read/write to the savedvalue field. + */ + + ri = PMC_TO_ROWINDEX(pm); + pcd = pmc_ri_to_classdep(md, ri, &adjri); + + mtx_pool_lock_spin(pmc_mtxpool, pm); + cpu = curthread->td_oncpu; + + if ((prw->pm_flags & PMC_F_OLDVALUE) != 0) { + if ((pm->pm_flags & PMC_F_ATTACHED_TO_OWNER) && + (pm->pm_state == PMC_STATE_RUNNING)) { + error = (*pcd->pcd_read_pmc)(cpu, adjri, pm, + valp); + } else { + *valp = pm->pm_gv.pm_savedvalue; + } + } + + if ((prw->pm_flags & PMC_F_NEWVALUE) != 0) + pm->pm_gv.pm_savedvalue = prw->pm_value; + + mtx_pool_unlock_spin(pmc_mtxpool, pm); + } else { /* System mode PMCs */ + cpu = PMC_TO_CPU(pm); + ri = PMC_TO_ROWINDEX(pm); + pcd = pmc_ri_to_classdep(md, ri, &adjri); + + if (!pmc_cpu_is_active(cpu)) + return (ENXIO); + + /* Move this thread to CPU 'cpu'. */ + pmc_save_cpu_binding(&pb); + pmc_select_cpu(cpu); + critical_enter(); + + /* Save old value. */ + if ((prw->pm_flags & PMC_F_OLDVALUE) != 0) + error = (*pcd->pcd_read_pmc)(cpu, adjri, pm, valp); + + /* Write out new value. */ + if (error == 0 && (prw->pm_flags & PMC_F_NEWVALUE) != 0) + error = (*pcd->pcd_write_pmc)(cpu, adjri, pm, + prw->pm_value); + + critical_exit(); + pmc_restore_cpu_binding(&pb); + if (error != 0) + return (error); + } + +#ifdef HWPMC_DEBUG + if ((prw->pm_flags & PMC_F_NEWVALUE) != 0) + PMCDBG3(PMC,OPS,2, "rw id=%d new %jx -> old %jx", + ri, prw->pm_value, *valp); + else + PMCDBG2(PMC,OPS,2, "rw id=%d -> old %jx", ri, *valp); +#endif + return (error); +} + static int pmc_syscall_handler(struct thread *td, void *syscall_args) { @@ -4253,136 +4357,31 @@ pmc_syscall_handler(struct thread *td, void *syscall_args) } break; - /* * Read and/or write a PMC. */ - case PMC_OP_PMCRW: { - int adjri; - struct pmc *pm; - uint32_t cpu, ri; - pmc_value_t oldvalue; - struct pmc_binding pb; struct pmc_op_pmcrw prw; - struct pmc_classdep *pcd; struct pmc_op_pmcrw *pprw; + pmc_value_t oldvalue; PMC_DOWNGRADE_SX(); - if ((error = copyin(arg, &prw, sizeof(prw))) != 0) - break; - - PMCDBG2(PMC,OPS,1, "rw id=%d flags=0x%x", prw.pm_pmcid, - prw.pm_flags); - - /* must have at least one flag set */ - if ((prw.pm_flags & (PMC_F_OLDVALUE|PMC_F_NEWVALUE)) == 0) { - error = EINVAL; - break; - } - - /* locate pmc descriptor */ - if ((error = pmc_find_pmc(prw.pm_pmcid, &pm)) != 0) + error = copyin(arg, &prw, sizeof(prw)); + if (error != 0) break; - /* Can't read a PMC that hasn't been started. */ - if (pm->pm_state != PMC_STATE_ALLOCATED && - pm->pm_state != PMC_STATE_STOPPED && - pm->pm_state != PMC_STATE_RUNNING) { - error = EINVAL; + error = pmc_do_op_pmcrw(&prw, &oldvalue); + if (error != 0) break; - } - /* writing a new value is allowed only for 'STOPPED' pmcs */ - if (pm->pm_state == PMC_STATE_RUNNING && - (prw.pm_flags & PMC_F_NEWVALUE)) { - error = EBUSY; - break; + /* Return old value if requested. */ + if ((prw.pm_flags & PMC_F_OLDVALUE) != 0) { + pprw = arg; + error = copyout(&oldvalue, &pprw->pm_value, + sizeof(prw.pm_value)); } - - if (PMC_IS_VIRTUAL_MODE(PMC_TO_MODE(pm))) { - - /* - * If this PMC is attached to its owner (i.e., - * the process requesting this operation) and - * is running, then attempt to get an - * upto-date reading from hardware for a READ. - * Writes are only allowed when the PMC is - * stopped, so only update the saved value - * field. - * - * If the PMC is not running, or is not - * attached to its owner, read/write to the - * savedvalue field. - */ - - ri = PMC_TO_ROWINDEX(pm); - pcd = pmc_ri_to_classdep(md, ri, &adjri); - - mtx_pool_lock_spin(pmc_mtxpool, pm); - cpu = curthread->td_oncpu; - - if (prw.pm_flags & PMC_F_OLDVALUE) { - if ((pm->pm_flags & PMC_F_ATTACHED_TO_OWNER) && - (pm->pm_state == PMC_STATE_RUNNING)) - error = (*pcd->pcd_read_pmc)(cpu, adjri, - pm, &oldvalue); - else - oldvalue = pm->pm_gv.pm_savedvalue; - } - if (prw.pm_flags & PMC_F_NEWVALUE) - pm->pm_gv.pm_savedvalue = prw.pm_value; - - mtx_pool_unlock_spin(pmc_mtxpool, pm); - - } else { /* System mode PMCs */ - cpu = PMC_TO_CPU(pm); - ri = PMC_TO_ROWINDEX(pm); - pcd = pmc_ri_to_classdep(md, ri, &adjri); - - if (!pmc_cpu_is_active(cpu)) { - error = ENXIO; - break; - } - - /* move this thread to CPU 'cpu' */ - pmc_save_cpu_binding(&pb); - pmc_select_cpu(cpu); - - critical_enter(); - /* save old value */ - if (prw.pm_flags & PMC_F_OLDVALUE) { - if ((error = (*pcd->pcd_read_pmc)(cpu, adjri, - pm, &oldvalue))) - goto error; - } - /* write out new value */ - if (prw.pm_flags & PMC_F_NEWVALUE) - error = (*pcd->pcd_write_pmc)(cpu, adjri, pm, - prw.pm_value); - error: - critical_exit(); - pmc_restore_cpu_binding(&pb); - if (error) - break; - } - - pprw = (struct pmc_op_pmcrw *) arg; - -#ifdef HWPMC_DEBUG - if (prw.pm_flags & PMC_F_NEWVALUE) - PMCDBG3(PMC,OPS,2, "rw id=%d new %jx -> old %jx", - ri, prw.pm_value, oldvalue); - else if (prw.pm_flags & PMC_F_OLDVALUE) - PMCDBG2(PMC,OPS,2, "rw id=%d -> old %jx", ri, oldvalue); -#endif - /* return old value if requested */ - if (prw.pm_flags & PMC_F_OLDVALUE) - if ((error = copyout(&oldvalue, &pprw->pm_value, - sizeof(prw.pm_value)))) - break; } break;
