From 668f62ec621e4e2919fb7d4caa5d805764c5852d Mon Sep 17 00:00:00 2001 From: Markus Armbruster Date: Tue, 7 Jul 2020 18:06:02 +0200 Subject: error: Eliminate error_propagate() with Coccinelle, part 1 When all we do with an Error we receive into a local variable is propagating to somewhere else, we can just as well receive it there right away. Convert if (!foo(..., &err)) { ... error_propagate(errp, err); ... return ... } to if (!foo(..., errp)) { ... ... return ... } where nothing else needs @err. Coccinelle script: @rule1 forall@ identifier fun, err, errp, lbl; expression list args, args2; binary operator op; constant c1, c2; symbol false; @@ if ( ( - fun(args, &err, args2) + fun(args, errp, args2) | - !fun(args, &err, args2) + !fun(args, errp, args2) | - fun(args, &err, args2) op c1 + fun(args, errp, args2) op c1 ) ) { ... when != err when != lbl: when strict - error_propagate(errp, err); ... when != err ( return; | return c2; | return false; ) } @rule2 forall@ identifier fun, err, errp, lbl; expression list args, args2; expression var; binary operator op; constant c1, c2; symbol false; @@ - var = fun(args, &err, args2); + var = fun(args, errp, args2); ... when != err if ( ( var | !var | var op c1 ) ) { ... when != err when != lbl: when strict - error_propagate(errp, err); ... when != err ( return; | return c2; | return false; | return var; ) } @depends on rule1 || rule2@ identifier err; @@ - Error *err = NULL; ... when != err Not exactly elegant, I'm afraid. The "when != lbl:" is necessary to avoid transforming if (fun(args, &err)) { goto out } ... out: error_propagate(errp, err); even though other paths to label out still need the error_propagate(). For an actual example, see sclp_realize(). Without the "when strict", Coccinelle transforms vfio_msix_setup(), incorrectly. I don't know what exactly "when strict" does, only that it helps here. The match of return is narrower than what I want, but I can't figure out how to express "return where the operand doesn't use @err". For an example where it's too narrow, see vfio_intx_enable(). Silently fails to convert hw/arm/armsse.c, because Coccinelle gets confused by ARMSSE being used both as typedef and function-like macro there. Converted manually. Line breaks tidied up manually. One nested declaration of @local_err deleted manually. Preexisting unwanted blank line dropped in hw/riscv/sifive_e.c. Signed-off-by: Markus Armbruster Reviewed-by: Eric Blake Message-Id: <20200707160613.848843-35-armbru@redhat.com> --- hw/pci-host/pnv_phb3.c | 10 +++------- hw/pci-host/pnv_phb4.c | 4 +--- hw/pci-host/pnv_phb4_pec.c | 4 +--- 3 files changed, 5 insertions(+), 13 deletions(-) (limited to 'hw/pci-host') diff --git a/hw/pci-host/pnv_phb3.c b/hw/pci-host/pnv_phb3.c index 94cb989136..82132c12ca 100644 --- a/hw/pci-host/pnv_phb3.c +++ b/hw/pci-host/pnv_phb3.c @@ -990,7 +990,6 @@ static void pnv_phb3_realize(DeviceState *dev, Error **errp) PnvPHB3 *phb = PNV_PHB3(dev); PCIHostState *pci = PCI_HOST_BRIDGE(dev); PnvMachineState *pnv = PNV_MACHINE(qdev_get_machine()); - Error *local_err = NULL; int i; if (phb->phb_id >= PNV8_CHIP_PHB3_MAX) { @@ -1003,8 +1002,7 @@ static void pnv_phb3_realize(DeviceState *dev, Error **errp) &error_abort); object_property_set_int(OBJECT(&phb->lsis), "nr-irqs", PNV_PHB3_NUM_LSI, &error_abort); - if (!qdev_realize(DEVICE(&phb->lsis), NULL, &local_err)) { - error_propagate(errp, local_err); + if (!qdev_realize(DEVICE(&phb->lsis), NULL, errp)) { return; } @@ -1021,16 +1019,14 @@ static void pnv_phb3_realize(DeviceState *dev, Error **errp) &error_abort); object_property_set_int(OBJECT(&phb->msis), "nr-irqs", PHB3_MAX_MSI, &error_abort); - if (!qdev_realize(DEVICE(&phb->msis), NULL, &local_err)) { - error_propagate(errp, local_err); + if (!qdev_realize(DEVICE(&phb->msis), NULL, errp)) { return; } /* Power Bus Common Queue */ object_property_set_link(OBJECT(&phb->pbcq), "phb", OBJECT(phb), &error_abort); - if (!qdev_realize(DEVICE(&phb->pbcq), NULL, &local_err)) { - error_propagate(errp, local_err); + if (!qdev_realize(DEVICE(&phb->pbcq), NULL, errp)) { return; } diff --git a/hw/pci-host/pnv_phb4.c b/hw/pci-host/pnv_phb4.c index a598c89eb0..75ad766fe0 100644 --- a/hw/pci-host/pnv_phb4.c +++ b/hw/pci-host/pnv_phb4.c @@ -1169,7 +1169,6 @@ static void pnv_phb4_realize(DeviceState *dev, Error **errp) PnvPHB4 *phb = PNV_PHB4(dev); PCIHostState *pci = PCI_HOST_BRIDGE(dev); XiveSource *xsrc = &phb->xsrc; - Error *local_err = NULL; int nr_irqs; char name[32]; @@ -1218,8 +1217,7 @@ static void pnv_phb4_realize(DeviceState *dev, Error **errp) } object_property_set_int(OBJECT(xsrc), "nr-irqs", nr_irqs, &error_fatal); object_property_set_link(OBJECT(xsrc), "xive", OBJECT(phb), &error_fatal); - if (!qdev_realize(DEVICE(xsrc), NULL, &local_err)) { - error_propagate(errp, local_err); + if (!qdev_realize(DEVICE(xsrc), NULL, errp)) { return; } diff --git a/hw/pci-host/pnv_phb4_pec.c b/hw/pci-host/pnv_phb4_pec.c index 088ab753aa..741ddc90ed 100644 --- a/hw/pci-host/pnv_phb4_pec.c +++ b/hw/pci-host/pnv_phb4_pec.c @@ -377,7 +377,6 @@ static void pnv_pec_instance_init(Object *obj) static void pnv_pec_realize(DeviceState *dev, Error **errp) { PnvPhb4PecState *pec = PNV_PHB4_PEC(dev); - Error *local_err = NULL; char name[64]; int i; @@ -390,8 +389,7 @@ static void pnv_pec_realize(DeviceState *dev, Error **errp) object_property_set_int(stk_obj, "stack-no", i, &error_abort); object_property_set_link(stk_obj, "pec", OBJECT(pec), &error_abort); - if (!qdev_realize(DEVICE(stk_obj), NULL, &local_err)) { - error_propagate(errp, local_err); + if (!qdev_realize(DEVICE(stk_obj), NULL, errp)) { return; } } -- cgit v1.2.3