From 4d0128ec58e109faed3f6357f982a0079361075a Mon Sep 17 00:00:00 2001 From: Alvin Chang Date: Wed, 26 Mar 2025 14:20:51 +0800 Subject: [PATCH] lib: sbi_domain: Reduce memory usage of per-domain hart context In current implementation, the length of hartindex_to_context_table[] array is fixed as SBI_HARTMASK_MAX_BITS. However, the number of harts supported by the platform might not be SBI_HARTMASK_MAX_BITS and is usually smaller than SBI_HARTMASK_MAX_BITS. This means it is unnecessary to allocate such fixed-length array here. Precisely, current implementation always allocates 1024 bytes for hartindex_to_context_table[128] on RV64 platform. However, a platform supports two harts only needs hartindex_to_context_table[2], which only needs 16 bytes. This commit calculates needed size of hartindex_to_context_table[] according to supported number of harts on the platform when registering per-domain data, so that memory usage of per-domain context data can be reduced. Signed-off-by: Alvin Chang Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/20250326062051.3763530-1-alvinga@andestech.com Signed-off-by: Anup Patel --- lib/sbi/sbi_domain_context.c | 35 +++++++++++++++++++++-------------- 1 file changed, 21 insertions(+), 14 deletions(-) diff --git a/lib/sbi/sbi_domain_context.c b/lib/sbi/sbi_domain_context.c index 407c0d5c..2b19fcc7 100644 --- a/lib/sbi/sbi_domain_context.c +++ b/lib/sbi/sbi_domain_context.c @@ -53,31 +53,30 @@ struct hart_context { bool initialized; }; -struct domain_context_priv { - /** Contexts for possible HARTs indexed by hartindex */ - struct hart_context *hartindex_to_context_table[SBI_HARTMASK_MAX_BITS]; -}; - -static struct sbi_domain_data dcpriv = { - .data_size = sizeof(struct domain_context_priv), -}; +static struct sbi_domain_data dcpriv; static inline struct hart_context *hart_context_get(struct sbi_domain *dom, u32 hartindex) { - struct domain_context_priv *dcp = sbi_domain_data_ptr(dom, &dcpriv); + struct hart_context **dom_hartindex_to_context_table; - return (dcp && hartindex < SBI_HARTMASK_MAX_BITS) ? - dcp->hartindex_to_context_table[hartindex] : NULL; + dom_hartindex_to_context_table = sbi_domain_data_ptr(dom, &dcpriv); + if (!dom_hartindex_to_context_table || !sbi_hartindex_valid(hartindex)) + return NULL; + + return dom_hartindex_to_context_table[hartindex]; } static void hart_context_set(struct sbi_domain *dom, u32 hartindex, struct hart_context *hc) { - struct domain_context_priv *dcp = sbi_domain_data_ptr(dom, &dcpriv); + struct hart_context **dom_hartindex_to_context_table; - if (dcp && hartindex < SBI_HARTMASK_MAX_BITS) - dcp->hartindex_to_context_table[hartindex] = hc; + dom_hartindex_to_context_table = sbi_domain_data_ptr(dom, &dcpriv); + if (!dom_hartindex_to_context_table || !sbi_hartindex_valid(hartindex)) + return; + + dom_hartindex_to_context_table[hartindex] = hc; } /** Macro to obtain the current hart's context pointer */ @@ -232,6 +231,14 @@ int sbi_domain_context_exit(void) int sbi_domain_context_init(void) { + /** + * Allocate per-domain and per-hart context data. + * The data type is "struct hart_context **" whose memory space will be + * dynamically allocated by domain_setup_data_one(). Calculate needed + * size of memory space here. + */ + dcpriv.data_size = sizeof(struct hart_context *) * sbi_hart_count(); + return sbi_domain_register_data(&dcpriv); }